* [PATCH 25/32] docs/vm: transhuge.txt: convert to ReST format
From: Mike Rapoport @ 2018-03-21 19:22 UTC (permalink / raw)
To: Jonathan Corbet
Cc: Andrey Ryabinin, Richard Henderson, Ivan Kokshaysky, Matt Turner,
Tony Luck, Fenghua Yu, Ralf Baechle, James Hogan,
Michael Ellerman, Alexander Viro, linux-kernel, linux-doc,
kasan-dev, linux-alpha, linux-ia64, linux-mips, linuxppc-dev,
linux-fsdevel, linux-mm, Mike Rapoport
In-Reply-To: <1521660168-14372-1-git-send-email-rppt@linux.vnet.ibm.com>
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
---
Documentation/vm/transhuge.txt | 286 ++++++++++++++++++++++++-----------------
1 file changed, 166 insertions(+), 120 deletions(-)
diff --git a/Documentation/vm/transhuge.txt b/Documentation/vm/transhuge.txt
index 4dde03b..569d182 100644
--- a/Documentation/vm/transhuge.txt
+++ b/Documentation/vm/transhuge.txt
@@ -1,6 +1,11 @@
-= Transparent Hugepage Support =
+.. _transhuge:
-== Objective ==
+============================
+Transparent Hugepage Support
+============================
+
+Objective
+=========
Performance critical computing applications dealing with large memory
working sets are already running on top of libhugetlbfs and in turn
@@ -33,7 +38,8 @@ are using hugepages but a significant speedup already happens if only
one of the two is using hugepages just because of the fact the TLB
miss is going to run faster.
-== Design ==
+Design
+======
- "graceful fallback": mm components which don't have transparent hugepage
knowledge fall back to breaking huge pmd mapping into table of ptes and,
@@ -88,16 +94,17 @@ Applications that gets a lot of benefit from hugepages and that don't
risk to lose memory by using hugepages, should use
madvise(MADV_HUGEPAGE) on their critical mmapped regions.
-== sysfs ==
+sysfs
+=====
Transparent Hugepage Support for anonymous memory can be entirely disabled
(mostly for debugging purposes) or only enabled inside MADV_HUGEPAGE
regions (to avoid the risk of consuming more memory resources) or enabled
-system wide. This can be achieved with one of:
+system wide. This can be achieved with one of::
-echo always >/sys/kernel/mm/transparent_hugepage/enabled
-echo madvise >/sys/kernel/mm/transparent_hugepage/enabled
-echo never >/sys/kernel/mm/transparent_hugepage/enabled
+ echo always >/sys/kernel/mm/transparent_hugepage/enabled
+ echo madvise >/sys/kernel/mm/transparent_hugepage/enabled
+ echo never >/sys/kernel/mm/transparent_hugepage/enabled
It's also possible to limit defrag efforts in the VM to generate
anonymous hugepages in case they're not immediately free to madvise
@@ -108,44 +115,53 @@ use hugepages later instead of regular pages. This isn't always
guaranteed, but it may be more likely in case the allocation is for a
MADV_HUGEPAGE region.
-echo always >/sys/kernel/mm/transparent_hugepage/defrag
-echo defer >/sys/kernel/mm/transparent_hugepage/defrag
-echo defer+madvise >/sys/kernel/mm/transparent_hugepage/defrag
-echo madvise >/sys/kernel/mm/transparent_hugepage/defrag
-echo never >/sys/kernel/mm/transparent_hugepage/defrag
-
-"always" means that an application requesting THP will stall on allocation
-failure and directly reclaim pages and compact memory in an effort to
-allocate a THP immediately. This may be desirable for virtual machines
-that benefit heavily from THP use and are willing to delay the VM start
-to utilise them.
-
-"defer" means that an application will wake kswapd in the background
-to reclaim pages and wake kcompactd to compact memory so that THP is
-available in the near future. It's the responsibility of khugepaged
-to then install the THP pages later.
-
-"defer+madvise" will enter direct reclaim and compaction like "always", but
-only for regions that have used madvise(MADV_HUGEPAGE); all other regions
-will wake kswapd in the background to reclaim pages and wake kcompactd to
-compact memory so that THP is available in the near future.
-
-"madvise" will enter direct reclaim like "always" but only for regions
-that are have used madvise(MADV_HUGEPAGE). This is the default behaviour.
-
-"never" should be self-explanatory.
+::
+
+ echo always >/sys/kernel/mm/transparent_hugepage/defrag
+ echo defer >/sys/kernel/mm/transparent_hugepage/defrag
+ echo defer+madvise >/sys/kernel/mm/transparent_hugepage/defrag
+ echo madvise >/sys/kernel/mm/transparent_hugepage/defrag
+ echo never >/sys/kernel/mm/transparent_hugepage/defrag
+
+always
+ means that an application requesting THP will stall on
+ allocation failure and directly reclaim pages and compact
+ memory in an effort to allocate a THP immediately. This may be
+ desirable for virtual machines that benefit heavily from THP
+ use and are willing to delay the VM start to utilise them.
+
+defer
+ means that an application will wake kswapd in the background
+ to reclaim pages and wake kcompactd to compact memory so that
+ THP is available in the near future. It's the responsibility
+ of khugepaged to then install the THP pages later.
+
+defer+madvise
+ will enter direct reclaim and compaction like ``always``, but
+ only for regions that have used madvise(MADV_HUGEPAGE); all
+ other regions will wake kswapd in the background to reclaim
+ pages and wake kcompactd to compact memory so that THP is
+ available in the near future.
+
+madvise
+ will enter direct reclaim like ``always`` but only for regions
+ that are have used madvise(MADV_HUGEPAGE). This is the default
+ behaviour.
+
+never
+ should be self-explanatory.
By default kernel tries to use huge zero page on read page fault to
anonymous mapping. It's possible to disable huge zero page by writing 0
-or enable it back by writing 1:
+or enable it back by writing 1::
-echo 0 >/sys/kernel/mm/transparent_hugepage/use_zero_page
-echo 1 >/sys/kernel/mm/transparent_hugepage/use_zero_page
+ echo 0 >/sys/kernel/mm/transparent_hugepage/use_zero_page
+ echo 1 >/sys/kernel/mm/transparent_hugepage/use_zero_page
Some userspace (such as a test program, or an optimized memory allocation
-library) may want to know the size (in bytes) of a transparent hugepage:
+library) may want to know the size (in bytes) of a transparent hugepage::
-cat /sys/kernel/mm/transparent_hugepage/hpage_pmd_size
+ cat /sys/kernel/mm/transparent_hugepage/hpage_pmd_size
khugepaged will be automatically started when
transparent_hugepage/enabled is set to "always" or "madvise, and it'll
@@ -155,84 +171,86 @@ khugepaged runs usually at low frequency so while one may not want to
invoke defrag algorithms synchronously during the page faults, it
should be worth invoking defrag at least in khugepaged. However it's
also possible to disable defrag in khugepaged by writing 0 or enable
-defrag in khugepaged by writing 1:
+defrag in khugepaged by writing 1::
-echo 0 >/sys/kernel/mm/transparent_hugepage/khugepaged/defrag
-echo 1 >/sys/kernel/mm/transparent_hugepage/khugepaged/defrag
+ echo 0 >/sys/kernel/mm/transparent_hugepage/khugepaged/defrag
+ echo 1 >/sys/kernel/mm/transparent_hugepage/khugepaged/defrag
You can also control how many pages khugepaged should scan at each
-pass:
+pass::
-/sys/kernel/mm/transparent_hugepage/khugepaged/pages_to_scan
+ /sys/kernel/mm/transparent_hugepage/khugepaged/pages_to_scan
and how many milliseconds to wait in khugepaged between each pass (you
-can set this to 0 to run khugepaged at 100% utilization of one core):
+can set this to 0 to run khugepaged at 100% utilization of one core)::
-/sys/kernel/mm/transparent_hugepage/khugepaged/scan_sleep_millisecs
+ /sys/kernel/mm/transparent_hugepage/khugepaged/scan_sleep_millisecs
and how many milliseconds to wait in khugepaged if there's an hugepage
-allocation failure to throttle the next allocation attempt.
+allocation failure to throttle the next allocation attempt::
-/sys/kernel/mm/transparent_hugepage/khugepaged/alloc_sleep_millisecs
+ /sys/kernel/mm/transparent_hugepage/khugepaged/alloc_sleep_millisecs
-The khugepaged progress can be seen in the number of pages collapsed:
+The khugepaged progress can be seen in the number of pages collapsed::
-/sys/kernel/mm/transparent_hugepage/khugepaged/pages_collapsed
+ /sys/kernel/mm/transparent_hugepage/khugepaged/pages_collapsed
-for each pass:
+for each pass::
-/sys/kernel/mm/transparent_hugepage/khugepaged/full_scans
+ /sys/kernel/mm/transparent_hugepage/khugepaged/full_scans
-max_ptes_none specifies how many extra small pages (that are
+``max_ptes_none`` specifies how many extra small pages (that are
not already mapped) can be allocated when collapsing a group
-of small pages into one large page.
+of small pages into one large page::
-/sys/kernel/mm/transparent_hugepage/khugepaged/max_ptes_none
+ /sys/kernel/mm/transparent_hugepage/khugepaged/max_ptes_none
A higher value leads to use additional memory for programs.
A lower value leads to gain less thp performance. Value of
max_ptes_none can waste cpu time very little, you can
ignore it.
-max_ptes_swap specifies how many pages can be brought in from
-swap when collapsing a group of pages into a transparent huge page.
+``max_ptes_swap`` specifies how many pages can be brought in from
+swap when collapsing a group of pages into a transparent huge page::
-/sys/kernel/mm/transparent_hugepage/khugepaged/max_ptes_swap
+ /sys/kernel/mm/transparent_hugepage/khugepaged/max_ptes_swap
A higher value can cause excessive swap IO and waste
memory. A lower value can prevent THPs from being
collapsed, resulting fewer pages being collapsed into
THPs, and lower memory access performance.
-== Boot parameter ==
+Boot parameter
+==============
You can change the sysfs boot time defaults of Transparent Hugepage
-Support by passing the parameter "transparent_hugepage=always" or
-"transparent_hugepage=madvise" or "transparent_hugepage=never"
-(without "") to the kernel command line.
+Support by passing the parameter ``transparent_hugepage=always`` or
+``transparent_hugepage=madvise`` or ``transparent_hugepage=never``
+to the kernel command line.
-== Hugepages in tmpfs/shmem ==
+Hugepages in tmpfs/shmem
+========================
You can control hugepage allocation policy in tmpfs with mount option
-"huge=". It can have following values:
+``huge=``. It can have following values:
- - "always":
+always
Attempt to allocate huge pages every time we need a new page;
- - "never":
+never
Do not allocate huge pages;
- - "within_size":
+within_size
Only allocate huge page if it will be fully within i_size.
Also respect fadvise()/madvise() hints;
- - "advise:
+advise
Only allocate huge pages if requested with fadvise()/madvise();
-The default policy is "never".
+The default policy is ``never``.
-"mount -o remount,huge= /mountpoint" works fine after mount: remounting
-huge=never will not attempt to break up huge pages at all, just stop more
+``mount -o remount,huge= /mountpoint`` works fine after mount: remounting
+``huge=never`` will not attempt to break up huge pages at all, just stop more
from being allocated.
There's also sysfs knob to control hugepage allocation policy for internal
@@ -243,110 +261,130 @@ MAP_ANONYMOUS), GPU drivers' DRM objects, Ashmem.
In addition to policies listed above, shmem_enabled allows two further
values:
- - "deny":
+deny
For use in emergencies, to force the huge option off from
all mounts;
- - "force":
+force
Force the huge option on for all - very useful for testing;
-== Need of application restart ==
+Need of application restart
+===========================
The transparent_hugepage/enabled values and tmpfs mount option only affect
future behavior. So to make them effective you need to restart any
application that could have been using hugepages. This also applies to the
regions registered in khugepaged.
-== Monitoring usage ==
+Monitoring usage
+================
The number of anonymous transparent huge pages currently used by the
-system is available by reading the AnonHugePages field in /proc/meminfo.
+system is available by reading the AnonHugePages field in ``/proc/meminfo``.
To identify what applications are using anonymous transparent huge pages,
-it is necessary to read /proc/PID/smaps and count the AnonHugePages fields
+it is necessary to read ``/proc/PID/smaps`` and count the AnonHugePages fields
for each mapping.
The number of file transparent huge pages mapped to userspace is available
-by reading ShmemPmdMapped and ShmemHugePages fields in /proc/meminfo.
+by reading ShmemPmdMapped and ShmemHugePages fields in ``/proc/meminfo``.
To identify what applications are mapping file transparent huge pages, it
-is necessary to read /proc/PID/smaps and count the FileHugeMapped fields
+is necessary to read ``/proc/PID/smaps`` and count the FileHugeMapped fields
for each mapping.
Note that reading the smaps file is expensive and reading it
frequently will incur overhead.
-There are a number of counters in /proc/vmstat that may be used to
+There are a number of counters in ``/proc/vmstat`` that may be used to
monitor how successfully the system is providing huge pages for use.
-thp_fault_alloc is incremented every time a huge page is successfully
+thp_fault_alloc
+ is incremented every time a huge page is successfully
allocated to handle a page fault. This applies to both the
first time a page is faulted and for COW faults.
-thp_collapse_alloc is incremented by khugepaged when it has found
+thp_collapse_alloc
+ is incremented by khugepaged when it has found
a range of pages to collapse into one huge page and has
successfully allocated a new huge page to store the data.
-thp_fault_fallback is incremented if a page fault fails to allocate
+thp_fault_fallback
+ is incremented if a page fault fails to allocate
a huge page and instead falls back to using small pages.
-thp_collapse_alloc_failed is incremented if khugepaged found a range
+thp_collapse_alloc_failed
+ is incremented if khugepaged found a range
of pages that should be collapsed into one huge page but failed
the allocation.
-thp_file_alloc is incremented every time a file huge page is successfully
+thp_file_alloc
+ is incremented every time a file huge page is successfully
allocated.
-thp_file_mapped is incremented every time a file huge page is mapped into
+thp_file_mapped
+ is incremented every time a file huge page is mapped into
user address space.
-thp_split_page is incremented every time a huge page is split into base
+thp_split_page
+ is incremented every time a huge page is split into base
pages. This can happen for a variety of reasons but a common
reason is that a huge page is old and is being reclaimed.
This action implies splitting all PMD the page mapped with.
-thp_split_page_failed is incremented if kernel fails to split huge
+thp_split_page_failed
+ is incremented if kernel fails to split huge
page. This can happen if the page was pinned by somebody.
-thp_deferred_split_page is incremented when a huge page is put onto split
+thp_deferred_split_page
+ is incremented when a huge page is put onto split
queue. This happens when a huge page is partially unmapped and
splitting it would free up some memory. Pages on split queue are
going to be split under memory pressure.
-thp_split_pmd is incremented every time a PMD split into table of PTEs.
+thp_split_pmd
+ is incremented every time a PMD split into table of PTEs.
This can happen, for instance, when application calls mprotect() or
munmap() on part of huge page. It doesn't split huge page, only
page table entry.
-thp_zero_page_alloc is incremented every time a huge zero page is
+thp_zero_page_alloc
+ is incremented every time a huge zero page is
successfully allocated. It includes allocations which where
dropped due race with other allocation. Note, it doesn't count
every map of the huge zero page, only its allocation.
-thp_zero_page_alloc_failed is incremented if kernel fails to allocate
+thp_zero_page_alloc_failed
+ is incremented if kernel fails to allocate
huge zero page and falls back to using small pages.
As the system ages, allocating huge pages may be expensive as the
system uses memory compaction to copy data around memory to free a
-huge page for use. There are some counters in /proc/vmstat to help
+huge page for use. There are some counters in ``/proc/vmstat`` to help
monitor this overhead.
-compact_stall is incremented every time a process stalls to run
+compact_stall
+ is incremented every time a process stalls to run
memory compaction so that a huge page is free for use.
-compact_success is incremented if the system compacted memory and
+compact_success
+ is incremented if the system compacted memory and
freed a huge page for use.
-compact_fail is incremented if the system tries to compact memory
+compact_fail
+ is incremented if the system tries to compact memory
but failed.
-compact_pages_moved is incremented each time a page is moved. If
+compact_pages_moved
+ is incremented each time a page is moved. If
this value is increasing rapidly, it implies that the system
is copying a lot of data to satisfy the huge page allocation.
It is possible that the cost of copying exceeds any savings
from reduced TLB misses.
-compact_pagemigrate_failed is incremented when the underlying mechanism
+compact_pagemigrate_failed
+ is incremented when the underlying mechanism
for moving a page failed.
-compact_blocks_moved is incremented each time memory compaction examines
+compact_blocks_moved
+ is incremented each time memory compaction examines
a huge page aligned range of pages.
It is possible to establish how long the stalls were using the function
@@ -354,7 +392,8 @@ tracer to record how long was spent in __alloc_pages_nodemask and
using the mm_page_alloc tracepoint to identify which allocations were
for huge pages.
-== get_user_pages and follow_page ==
+get_user_pages and follow_page
+==============================
get_user_pages and follow_page if run on a hugepage, will return the
head or tail pages as usual (exactly as they would do on
@@ -367,10 +406,11 @@ for the head page and not the tail page), it should be updated to jump
to check head page instead. Taking reference on any head/tail page would
prevent page from being split by anyone.
-NOTE: these aren't new constraints to the GUP API, and they match the
-same constrains that applies to hugetlbfs too, so any driver capable
-of handling GUP on hugetlbfs will also work fine on transparent
-hugepage backed mappings.
+.. note::
+ these aren't new constraints to the GUP API, and they match the
+ same constrains that applies to hugetlbfs too, so any driver capable
+ of handling GUP on hugetlbfs will also work fine on transparent
+ hugepage backed mappings.
In case you can't handle compound pages if they're returned by
follow_page, the FOLL_SPLIT bit can be specified as parameter to
@@ -383,13 +423,15 @@ hugepages being returned (as it's not only checking the pfn of the
page and pinning it during the copy but it pretends to migrate the
memory in regular page sizes and with regular pte/pmd mappings).
-== Optimizing the applications ==
+Optimizing the applications
+===========================
To be guaranteed that the kernel will map a 2M page immediately in any
memory region, the mmap region has to be hugepage naturally
aligned. posix_memalign() can provide that guarantee.
-== Hugetlbfs ==
+Hugetlbfs
+=========
You can use hugetlbfs on a kernel that has transparent hugepage
support enabled just fine as always. No difference can be noted in
@@ -397,7 +439,8 @@ hugetlbfs other than there will be less overall fragmentation. All
usual features belonging to hugetlbfs are preserved and
unaffected. libhugetlbfs will also work fine as usual.
-== Graceful fallback ==
+Graceful fallback
+=================
Code walking pagetables but unaware about huge pmds can simply call
split_huge_pmd(vma, pmd, addr) where the pmd is the one returned by
@@ -415,20 +458,21 @@ it tries to swapout the hugepage for example. split_huge_page() can fail
if the page is pinned and you must handle this correctly.
Example to make mremap.c transparent hugepage aware with a one liner
-change:
+change::
-diff --git a/mm/mremap.c b/mm/mremap.c
---- a/mm/mremap.c
-+++ b/mm/mremap.c
-@@ -41,6 +41,7 @@ static pmd_t *get_old_pmd(struct mm_stru
- return NULL;
+ diff --git a/mm/mremap.c b/mm/mremap.c
+ --- a/mm/mremap.c
+ +++ b/mm/mremap.c
+ @@ -41,6 +41,7 @@ static pmd_t *get_old_pmd(struct mm_stru
+ return NULL;
- pmd = pmd_offset(pud, addr);
-+ split_huge_pmd(vma, pmd, addr);
- if (pmd_none_or_clear_bad(pmd))
- return NULL;
+ pmd = pmd_offset(pud, addr);
+ + split_huge_pmd(vma, pmd, addr);
+ if (pmd_none_or_clear_bad(pmd))
+ return NULL;
-== Locking in hugepage aware code ==
+Locking in hugepage aware code
+==============================
We want as much code as possible hugepage aware, as calling
split_huge_page() or split_huge_pmd() has a cost.
@@ -448,7 +492,8 @@ should just drop the page table lock and fallback to the old code as
before. Otherwise you can proceed to process the huge pmd and the
hugepage natively. Once finished you can drop the page table lock.
-== Refcounts and transparent huge pages ==
+Refcounts and transparent huge pages
+====================================
Refcounting on THP is mostly consistent with refcounting on other compound
pages:
@@ -510,7 +555,8 @@ clear where reference should go after split: it will stay on head page.
Note that split_huge_pmd() doesn't have any limitation on refcounting:
pmd can be split at any point and never fails.
-== Partial unmap and deferred_split_huge_page() ==
+Partial unmap and deferred_split_huge_page()
+============================================
Unmapping part of THP (with munmap() or other way) is not going to free
memory immediately. Instead, we detect that a subpage of THP is not in use
--
2.7.4
^ permalink raw reply related
* [PATCH 26/32] docs/vm: unevictable-lru.txt: convert to ReST format
From: Mike Rapoport @ 2018-03-21 19:22 UTC (permalink / raw)
To: Jonathan Corbet
Cc: Andrey Ryabinin, Richard Henderson, Ivan Kokshaysky, Matt Turner,
Tony Luck, Fenghua Yu, Ralf Baechle, James Hogan,
Michael Ellerman, Alexander Viro, linux-kernel, linux-doc,
kasan-dev, linux-alpha, linux-ia64, linux-mips, linuxppc-dev,
linux-fsdevel, linux-mm, Mike Rapoport
In-Reply-To: <1521660168-14372-1-git-send-email-rppt@linux.vnet.ibm.com>
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
---
Documentation/vm/unevictable-lru.txt | 117 +++++++++++++++--------------------
1 file changed, 49 insertions(+), 68 deletions(-)
diff --git a/Documentation/vm/unevictable-lru.txt b/Documentation/vm/unevictable-lru.txt
index e147185..fdd84cb 100644
--- a/Documentation/vm/unevictable-lru.txt
+++ b/Documentation/vm/unevictable-lru.txt
@@ -1,37 +1,13 @@
- ==============================
- UNEVICTABLE LRU INFRASTRUCTURE
- ==============================
-
-========
-CONTENTS
-========
-
- (*) The Unevictable LRU
-
- - The unevictable page list.
- - Memory control group interaction.
- - Marking address spaces unevictable.
- - Detecting Unevictable Pages.
- - vmscan's handling of unevictable pages.
-
- (*) mlock()'d pages.
-
- - History.
- - Basic management.
- - mlock()/mlockall() system call handling.
- - Filtering special vmas.
- - munlock()/munlockall() system call handling.
- - Migrating mlocked pages.
- - Compacting mlocked pages.
- - mmap(MAP_LOCKED) system call handling.
- - munmap()/exit()/exec() system call handling.
- - try_to_unmap().
- - try_to_munlock() reverse map scan.
- - Page reclaim in shrink_*_list().
+.. _unevictable_lru:
+==============================
+Unevictable LRU Infrastructure
+==============================
-============
-INTRODUCTION
+.. contents:: :local:
+
+
+Introduction
============
This document describes the Linux memory manager's "Unevictable LRU"
@@ -46,8 +22,8 @@ details - the "what does it do?" - by reading the code. One hopes that the
descriptions below add value by provide the answer to "why does it do that?".
-===================
-THE UNEVICTABLE LRU
+
+The Unevictable LRU
===================
The Unevictable LRU facility adds an additional LRU list to track unevictable
@@ -66,17 +42,17 @@ completely unresponsive.
The unevictable list addresses the following classes of unevictable pages:
- (*) Those owned by ramfs.
+ * Those owned by ramfs.
- (*) Those mapped into SHM_LOCK'd shared memory regions.
+ * Those mapped into SHM_LOCK'd shared memory regions.
- (*) Those mapped into VM_LOCKED [mlock()ed] VMAs.
+ * Those mapped into VM_LOCKED [mlock()ed] VMAs.
The infrastructure may also be able to handle other conditions that make pages
unevictable, either by definition or by circumstance, in the future.
-THE UNEVICTABLE PAGE LIST
+The Unevictable Page List
-------------------------
The Unevictable LRU infrastructure consists of an additional, per-zone, LRU list
@@ -118,7 +94,7 @@ the unevictable list when one task has the page isolated from the LRU and other
tasks are changing the "evictability" state of the page.
-MEMORY CONTROL GROUP INTERACTION
+Memory Control Group Interaction
--------------------------------
The unevictable LRU facility interacts with the memory control group [aka
@@ -144,7 +120,9 @@ effects:
the control group to thrash or to OOM-kill tasks.
-MARKING ADDRESS SPACES UNEVICTABLE
+.. _mark_addr_space_unevict:
+
+Marking Address Spaces Unevictable
----------------------------------
For facilities such as ramfs none of the pages attached to the address space
@@ -152,15 +130,15 @@ may be evicted. To prevent eviction of any such pages, the AS_UNEVICTABLE
address space flag is provided, and this can be manipulated by a filesystem
using a number of wrapper functions:
- (*) void mapping_set_unevictable(struct address_space *mapping);
+ * ``void mapping_set_unevictable(struct address_space *mapping);``
Mark the address space as being completely unevictable.
- (*) void mapping_clear_unevictable(struct address_space *mapping);
+ * ``void mapping_clear_unevictable(struct address_space *mapping);``
Mark the address space as being evictable.
- (*) int mapping_unevictable(struct address_space *mapping);
+ * ``int mapping_unevictable(struct address_space *mapping);``
Query the address space, and return true if it is completely
unevictable.
@@ -177,12 +155,13 @@ These are currently used in two places in the kernel:
ensure they're in memory.
-DETECTING UNEVICTABLE PAGES
+Detecting Unevictable Pages
---------------------------
The function page_evictable() in vmscan.c determines whether a page is
-evictable or not using the query function outlined above [see section "Marking
-address spaces unevictable"] to check the AS_UNEVICTABLE flag.
+evictable or not using the query function outlined above [see section
+:ref:`Marking address spaces unevictable <mark_addr_space_unevict>`]
+to check the AS_UNEVICTABLE flag.
For address spaces that are so marked after being populated (as SHM regions
might be), the lock action (eg: SHM_LOCK) can be lazy, and need not populate
@@ -202,7 +181,7 @@ flag, PG_mlocked (as wrapped by PageMlocked()), which is set when a page is
faulted into a VM_LOCKED vma, or found in a vma being VM_LOCKED.
-VMSCAN'S HANDLING OF UNEVICTABLE PAGES
+Vmscan's Handling of Unevictable Pages
--------------------------------------
If unevictable pages are culled in the fault path, or moved to the unevictable
@@ -233,8 +212,7 @@ extra evictabilty checks should not occur in the majority of calls to
putback_lru_page().
-=============
-MLOCKED PAGES
+MLOCKED Pages
=============
The unevictable page list is also useful for mlock(), in addition to ramfs and
@@ -242,7 +220,7 @@ SYSV SHM. Note that mlock() is only available in CONFIG_MMU=y situations; in
NOMMU situations, all mappings are effectively mlocked.
-HISTORY
+History
-------
The "Unevictable mlocked Pages" infrastructure is based on work originally
@@ -263,7 +241,7 @@ replaced by walking the reverse map to determine whether any VM_LOCKED VMAs
mapped the page. More on this below.
-BASIC MANAGEMENT
+Basic Management
----------------
mlocked pages - pages mapped into a VM_LOCKED VMA - are a class of unevictable
@@ -304,10 +282,10 @@ mlocked pages become unlocked and rescued from the unevictable list when:
(4) before a page is COW'd in a VM_LOCKED VMA.
-mlock()/mlockall() SYSTEM CALL HANDLING
+mlock()/mlockall() System Call Handling
---------------------------------------
-Both [do_]mlock() and [do_]mlockall() system call handlers call mlock_fixup()
+Both [do\_]mlock() and [do\_]mlockall() system call handlers call mlock_fixup()
for each VMA in the range specified by the call. In the case of mlockall(),
this is the entire active address space of the task. Note that mlock_fixup()
is used for both mlocking and munlocking a range of memory. A call to mlock()
@@ -351,7 +329,7 @@ mlock_vma_page() is unable to isolate the page from the LRU, vmscan will handle
it later if and when it attempts to reclaim the page.
-FILTERING SPECIAL VMAS
+Filtering Special VMAs
----------------------
mlock_fixup() filters several classes of "special" VMAs:
@@ -379,8 +357,9 @@ VM_LOCKED flag. Therefore, we won't have to deal with them later during
munlock(), munmap() or task exit. Neither does mlock_fixup() account these
VMAs against the task's "locked_vm".
+.. _munlock_munlockall_handling:
-munlock()/munlockall() SYSTEM CALL HANDLING
+munlock()/munlockall() System Call Handling
-------------------------------------------
The munlock() and munlockall() system calls are handled by the same functions -
@@ -426,7 +405,7 @@ This is fine, because we'll catch it later if and if vmscan tries to reclaim
the page. This should be relatively rare.
-MIGRATING MLOCKED PAGES
+Migrating MLOCKED Pages
-----------------------
A page that is being migrated has been isolated from the LRU lists and is held
@@ -451,7 +430,7 @@ list because of a race between munlock and migration, page migration uses the
putback_lru_page() function to add migrated pages back to the LRU.
-COMPACTING MLOCKED PAGES
+Compacting MLOCKED Pages
------------------------
The unevictable LRU can be scanned for compactable regions and the default
@@ -461,7 +440,7 @@ unevictable LRU is enabled, the work of compaction is mostly handled by
the page migration code and the same work flow as described in MIGRATING
MLOCKED PAGES will apply.
-MLOCKING TRANSPARENT HUGE PAGES
+MLOCKING Transparent Huge Pages
-------------------------------
A transparent huge page is represented by a single entry on an LRU list.
@@ -483,7 +462,7 @@ to unevictable LRU and the rest can be reclaimed.
See also comment in follow_trans_huge_pmd().
-mmap(MAP_LOCKED) SYSTEM CALL HANDLING
+mmap(MAP_LOCKED) System Call Handling
-------------------------------------
In addition the mlock()/mlockall() system calls, an application can request
@@ -514,7 +493,7 @@ memory range accounted as locked_vm, as the protections could be changed later
and pages allocated into that region.
-munmap()/exit()/exec() SYSTEM CALL HANDLING
+munmap()/exit()/exec() System Call Handling
-------------------------------------------
When unmapping an mlocked region of memory, whether by an explicit call to
@@ -568,16 +547,18 @@ munlock or munmap system calls, mm teardown (munlock_vma_pages_all), reclaim,
holepunching, and truncation of file pages and their anonymous COWed pages.
-try_to_munlock() REVERSE MAP SCAN
+try_to_munlock() Reverse Map Scan
---------------------------------
- [!] TODO/FIXME: a better name might be page_mlocked() - analogous to the
- page_referenced() reverse map walker.
+.. warning::
+ [!] TODO/FIXME: a better name might be page_mlocked() - analogous to the
+ page_referenced() reverse map walker.
-When munlock_vma_page() [see section "munlock()/munlockall() System Call
-Handling" above] tries to munlock a page, it needs to determine whether or not
-the page is mapped by any VM_LOCKED VMA without actually attempting to unmap
-all PTEs from the page. For this purpose, the unevictable/mlock infrastructure
+When munlock_vma_page() [see section :ref:`munlock()/munlockall() System Call
+Handling <munlock_munlockall_handling>` above] tries to munlock a
+page, it needs to determine whether or not the page is mapped by any
+VM_LOCKED VMA without actually attempting to unmap all PTEs from the
+page. For this purpose, the unevictable/mlock infrastructure
introduced a variant of try_to_unmap() called try_to_munlock().
try_to_munlock() calls the same functions as try_to_unmap() for anonymous and
@@ -595,7 +576,7 @@ large region or tearing down a large address space that has been mlocked via
mlockall(), overall this is a fairly rare event.
-PAGE RECLAIM IN shrink_*_list()
+Page Reclaim in shrink_*_list()
-------------------------------
shrink_active_list() culls any obviously unevictable pages - i.e.
--
2.7.4
^ permalink raw reply related
* [PATCH 27/32] docs/vm: userfaultfd.txt: convert to ReST format
From: Mike Rapoport @ 2018-03-21 19:22 UTC (permalink / raw)
To: Jonathan Corbet
Cc: Andrey Ryabinin, Richard Henderson, Ivan Kokshaysky, Matt Turner,
Tony Luck, Fenghua Yu, Ralf Baechle, James Hogan,
Michael Ellerman, Alexander Viro, linux-kernel, linux-doc,
kasan-dev, linux-alpha, linux-ia64, linux-mips, linuxppc-dev,
linux-fsdevel, linux-mm, Mike Rapoport
In-Reply-To: <1521660168-14372-1-git-send-email-rppt@linux.vnet.ibm.com>
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
---
Documentation/vm/userfaultfd.txt | 66 ++++++++++++++++++++++++----------------
1 file changed, 39 insertions(+), 27 deletions(-)
diff --git a/Documentation/vm/userfaultfd.txt b/Documentation/vm/userfaultfd.txt
index bb2f945..5048cf6 100644
--- a/Documentation/vm/userfaultfd.txt
+++ b/Documentation/vm/userfaultfd.txt
@@ -1,6 +1,11 @@
-= Userfaultfd =
+.. _userfaultfd:
-== Objective ==
+===========
+Userfaultfd
+===========
+
+Objective
+=========
Userfaults allow the implementation of on-demand paging from userland
and more generally they allow userland to take control of various
@@ -9,7 +14,8 @@ memory page faults, something otherwise only the kernel code could do.
For example userfaults allows a proper and more optimal implementation
of the PROT_NONE+SIGSEGV trick.
-== Design ==
+Design
+======
Userfaults are delivered and resolved through the userfaultfd syscall.
@@ -41,7 +47,8 @@ different processes without them being aware about what is going on
themselves on the same region the manager is already tracking, which
is a corner case that would currently return -EBUSY).
-== API ==
+API
+===
When first opened the userfaultfd must be enabled invoking the
UFFDIO_API ioctl specifying a uffdio_api.api value set to UFFD_API (or
@@ -101,7 +108,8 @@ UFFDIO_COPY. They're atomic as in guaranteeing that nothing can see an
half copied page since it'll keep userfaulting until the copy has
finished.
-== QEMU/KVM ==
+QEMU/KVM
+========
QEMU/KVM is using the userfaultfd syscall to implement postcopy live
migration. Postcopy live migration is one form of memory
@@ -163,7 +171,8 @@ sending the same page twice (in case the userfault is read by the
postcopy thread just before UFFDIO_COPY|ZEROPAGE runs in the migration
thread).
-== Non-cooperative userfaultfd ==
+Non-cooperative userfaultfd
+===========================
When the userfaultfd is monitored by an external manager, the manager
must be able to track changes in the process virtual memory
@@ -172,27 +181,30 @@ the same read(2) protocol as for the page fault notifications. The
manager has to explicitly enable these events by setting appropriate
bits in uffdio_api.features passed to UFFDIO_API ioctl:
-UFFD_FEATURE_EVENT_FORK - enable userfaultfd hooks for fork(). When
-this feature is enabled, the userfaultfd context of the parent process
-is duplicated into the newly created process. The manager receives
-UFFD_EVENT_FORK with file descriptor of the new userfaultfd context in
-the uffd_msg.fork.
-
-UFFD_FEATURE_EVENT_REMAP - enable notifications about mremap()
-calls. When the non-cooperative process moves a virtual memory area to
-a different location, the manager will receive UFFD_EVENT_REMAP. The
-uffd_msg.remap will contain the old and new addresses of the area and
-its original length.
-
-UFFD_FEATURE_EVENT_REMOVE - enable notifications about
-madvise(MADV_REMOVE) and madvise(MADV_DONTNEED) calls. The event
-UFFD_EVENT_REMOVE will be generated upon these calls to madvise. The
-uffd_msg.remove will contain start and end addresses of the removed
-area.
-
-UFFD_FEATURE_EVENT_UNMAP - enable notifications about memory
-unmapping. The manager will get UFFD_EVENT_UNMAP with uffd_msg.remove
-containing start and end addresses of the unmapped area.
+UFFD_FEATURE_EVENT_FORK
+ enable userfaultfd hooks for fork(). When this feature is
+ enabled, the userfaultfd context of the parent process is
+ duplicated into the newly created process. The manager
+ receives UFFD_EVENT_FORK with file descriptor of the new
+ userfaultfd context in the uffd_msg.fork.
+
+UFFD_FEATURE_EVENT_REMAP
+ enable notifications about mremap() calls. When the
+ non-cooperative process moves a virtual memory area to a
+ different location, the manager will receive
+ UFFD_EVENT_REMAP. The uffd_msg.remap will contain the old and
+ new addresses of the area and its original length.
+
+UFFD_FEATURE_EVENT_REMOVE
+ enable notifications about madvise(MADV_REMOVE) and
+ madvise(MADV_DONTNEED) calls. The event UFFD_EVENT_REMOVE will
+ be generated upon these calls to madvise. The uffd_msg.remove
+ will contain start and end addresses of the removed area.
+
+UFFD_FEATURE_EVENT_UNMAP
+ enable notifications about memory unmapping. The manager will
+ get UFFD_EVENT_UNMAP with uffd_msg.remove containing start and
+ end addresses of the unmapped area.
Although the UFFD_FEATURE_EVENT_REMOVE and UFFD_FEATURE_EVENT_UNMAP
are pretty similar, they quite differ in the action expected from the
--
2.7.4
^ permalink raw reply related
* [PATCH 28/32] docs/vm: z3fold.txt: convert to ReST format
From: Mike Rapoport @ 2018-03-21 19:22 UTC (permalink / raw)
To: Jonathan Corbet
Cc: Andrey Ryabinin, Richard Henderson, Ivan Kokshaysky, Matt Turner,
Tony Luck, Fenghua Yu, Ralf Baechle, James Hogan,
Michael Ellerman, Alexander Viro, linux-kernel, linux-doc,
kasan-dev, linux-alpha, linux-ia64, linux-mips, linuxppc-dev,
linux-fsdevel, linux-mm, Mike Rapoport
In-Reply-To: <1521660168-14372-1-git-send-email-rppt@linux.vnet.ibm.com>
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
---
Documentation/vm/z3fold.txt | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/Documentation/vm/z3fold.txt b/Documentation/vm/z3fold.txt
index 38e4dac..224e3c6 100644
--- a/Documentation/vm/z3fold.txt
+++ b/Documentation/vm/z3fold.txt
@@ -1,5 +1,8 @@
+.. _z3fold:
+
+======
z3fold
-------
+======
z3fold is a special purpose allocator for storing compressed pages.
It is designed to store up to three compressed pages per physical page.
@@ -7,6 +10,7 @@ It is a zbud derivative which allows for higher compression
ratio keeping the simplicity and determinism of its predecessor.
The main differences between z3fold and zbud are:
+
* unlike zbud, z3fold allows for up to PAGE_SIZE allocations
* z3fold can hold up to 3 compressed pages in its page
* z3fold doesn't export any API itself and is thus intended to be used
--
2.7.4
^ permalink raw reply related
* [PATCH 29/32] docs/vm: zsmalloc.txt: convert to ReST format
From: Mike Rapoport @ 2018-03-21 19:22 UTC (permalink / raw)
To: Jonathan Corbet
Cc: Andrey Ryabinin, Richard Henderson, Ivan Kokshaysky, Matt Turner,
Tony Luck, Fenghua Yu, Ralf Baechle, James Hogan,
Michael Ellerman, Alexander Viro, linux-kernel, linux-doc,
kasan-dev, linux-alpha, linux-ia64, linux-mips, linuxppc-dev,
linux-fsdevel, linux-mm, Mike Rapoport
In-Reply-To: <1521660168-14372-1-git-send-email-rppt@linux.vnet.ibm.com>
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
---
Documentation/vm/zsmalloc.txt | 60 ++++++++++++++++++++++++++-----------------
1 file changed, 36 insertions(+), 24 deletions(-)
diff --git a/Documentation/vm/zsmalloc.txt b/Documentation/vm/zsmalloc.txt
index 64ed63c..6e79893 100644
--- a/Documentation/vm/zsmalloc.txt
+++ b/Documentation/vm/zsmalloc.txt
@@ -1,5 +1,8 @@
+.. _zsmalloc:
+
+========
zsmalloc
---------
+========
This allocator is designed for use with zram. Thus, the allocator is
supposed to work well under low memory conditions. In particular, it
@@ -31,40 +34,49 @@ be mapped using zs_map_object() to get a usable pointer and subsequently
unmapped using zs_unmap_object().
stat
-----
+====
With CONFIG_ZSMALLOC_STAT, we could see zsmalloc internal information via
-/sys/kernel/debug/zsmalloc/<user name>. Here is a sample of stat output:
+``/sys/kernel/debug/zsmalloc/<user name>``. Here is a sample of stat output::
-# cat /sys/kernel/debug/zsmalloc/zram0/classes
+ # cat /sys/kernel/debug/zsmalloc/zram0/classes
class size almost_full almost_empty obj_allocated obj_used pages_used pages_per_zspage
- ..
- ..
+ ...
+ ...
9 176 0 1 186 129 8 4
10 192 1 0 2880 2872 135 3
11 208 0 1 819 795 42 2
12 224 0 1 219 159 12 4
- ..
- ..
+ ...
+ ...
+
+class
+ index
+size
+ object size zspage stores
+almost_empty
+ the number of ZS_ALMOST_EMPTY zspages(see below)
+almost_full
+ the number of ZS_ALMOST_FULL zspages(see below)
+obj_allocated
+ the number of objects allocated
+obj_used
+ the number of objects allocated to the user
+pages_used
+ the number of pages allocated for the class
+pages_per_zspage
+ the number of 0-order pages to make a zspage
-class: index
-size: object size zspage stores
-almost_empty: the number of ZS_ALMOST_EMPTY zspages(see below)
-almost_full: the number of ZS_ALMOST_FULL zspages(see below)
-obj_allocated: the number of objects allocated
-obj_used: the number of objects allocated to the user
-pages_used: the number of pages allocated for the class
-pages_per_zspage: the number of 0-order pages to make a zspage
+We assign a zspage to ZS_ALMOST_EMPTY fullness group when n <= N / f, where
-We assign a zspage to ZS_ALMOST_EMPTY fullness group when:
- n <= N / f, where
-n = number of allocated objects
-N = total number of objects zspage can store
-f = fullness_threshold_frac(ie, 4 at the moment)
+* n = number of allocated objects
+* N = total number of objects zspage can store
+* f = fullness_threshold_frac(ie, 4 at the moment)
Similarly, we assign zspage to:
- ZS_ALMOST_FULL when n > N / f
- ZS_EMPTY when n == 0
- ZS_FULL when n == N
+
+* ZS_ALMOST_FULL when n > N / f
+* ZS_EMPTY when n == 0
+* ZS_FULL when n == N
--
2.7.4
^ permalink raw reply related
* [PATCH 30/32] docs/vm: zswap.txt: convert to ReST format
From: Mike Rapoport @ 2018-03-21 19:22 UTC (permalink / raw)
To: Jonathan Corbet
Cc: Andrey Ryabinin, Richard Henderson, Ivan Kokshaysky, Matt Turner,
Tony Luck, Fenghua Yu, Ralf Baechle, James Hogan,
Michael Ellerman, Alexander Viro, linux-kernel, linux-doc,
kasan-dev, linux-alpha, linux-ia64, linux-mips, linuxppc-dev,
linux-fsdevel, linux-mm, Mike Rapoport
In-Reply-To: <1521660168-14372-1-git-send-email-rppt@linux.vnet.ibm.com>
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
---
Documentation/vm/zswap.txt | 71 +++++++++++++++++++++++++++-------------------
1 file changed, 42 insertions(+), 29 deletions(-)
diff --git a/Documentation/vm/zswap.txt b/Documentation/vm/zswap.txt
index 0b3a114..1444ecd 100644
--- a/Documentation/vm/zswap.txt
+++ b/Documentation/vm/zswap.txt
@@ -1,4 +1,11 @@
-Overview:
+.. _zswap:
+
+=====
+zswap
+=====
+
+Overview
+========
Zswap is a lightweight compressed cache for swap pages. It takes pages that are
in the process of being swapped out and attempts to compress them into a
@@ -7,32 +14,34 @@ for potentially reduced swap I/O. This trade-off can also result in a
significant performance improvement if reads from the compressed cache are
faster than reads from a swap device.
-NOTE: Zswap is a new feature as of v3.11 and interacts heavily with memory
-reclaim. This interaction has not been fully explored on the large set of
-potential configurations and workloads that exist. For this reason, zswap
-is a work in progress and should be considered experimental.
+.. note::
+ Zswap is a new feature as of v3.11 and interacts heavily with memory
+ reclaim. This interaction has not been fully explored on the large set of
+ potential configurations and workloads that exist. For this reason, zswap
+ is a work in progress and should be considered experimental.
+
+ Some potential benefits:
-Some potential benefits:
* Desktop/laptop users with limited RAM capacities can mitigate the
- performance impact of swapping.
+ performance impact of swapping.
* Overcommitted guests that share a common I/O resource can
- dramatically reduce their swap I/O pressure, avoiding heavy handed I/O
- throttling by the hypervisor. This allows more work to get done with less
- impact to the guest workload and guests sharing the I/O subsystem
+ dramatically reduce their swap I/O pressure, avoiding heavy handed I/O
+ throttling by the hypervisor. This allows more work to get done with less
+ impact to the guest workload and guests sharing the I/O subsystem
* Users with SSDs as swap devices can extend the life of the device by
- drastically reducing life-shortening writes.
+ drastically reducing life-shortening writes.
Zswap evicts pages from compressed cache on an LRU basis to the backing swap
device when the compressed pool reaches its size limit. This requirement had
been identified in prior community discussions.
Zswap is disabled by default but can be enabled at boot time by setting
-the "enabled" attribute to 1 at boot time. ie: zswap.enabled=1. Zswap
+the ``enabled`` attribute to 1 at boot time. ie: ``zswap.enabled=1``. Zswap
can also be enabled and disabled at runtime using the sysfs interface.
An example command to enable zswap at runtime, assuming sysfs is mounted
-at /sys, is:
+at ``/sys``, is::
-echo 1 > /sys/module/zswap/parameters/enabled
+ echo 1 > /sys/module/zswap/parameters/enabled
When zswap is disabled at runtime it will stop storing pages that are
being swapped out. However, it will _not_ immediately write out or fault
@@ -43,7 +52,8 @@ pages out of the compressed pool, a swapoff on the swap device(s) will
fault back into memory all swapped out pages, including those in the
compressed pool.
-Design:
+Design
+======
Zswap receives pages for compression through the Frontswap API and is able to
evict pages from its own compressed pool on an LRU basis and write them back to
@@ -53,12 +63,12 @@ Zswap makes use of zpool for the managing the compressed memory pool. Each
allocation in zpool is not directly accessible by address. Rather, a handle is
returned by the allocation routine and that handle must be mapped before being
accessed. The compressed memory pool grows on demand and shrinks as compressed
-pages are freed. The pool is not preallocated. By default, a zpool of type
-zbud is created, but it can be selected at boot time by setting the "zpool"
-attribute, e.g. zswap.zpool=zbud. It can also be changed at runtime using the
-sysfs "zpool" attribute, e.g.
+pages are freed. The pool is not preallocated. By default, a zpool
+of type zbud is created, but it can be selected at boot time by
+setting the ``zpool`` attribute, e.g. ``zswap.zpool=zbud``. It can
+also be changed at runtime using the sysfs ``zpool`` attribute, e.g.::
-echo zbud > /sys/module/zswap/parameters/zpool
+ echo zbud > /sys/module/zswap/parameters/zpool
The zbud type zpool allocates exactly 1 page to store 2 compressed pages, which
means the compression ratio will always be 2:1 or worse (because of half-full
@@ -83,14 +93,16 @@ via frontswap, to free the compressed entry.
Zswap seeks to be simple in its policies. Sysfs attributes allow for one user
controlled policy:
+
* max_pool_percent - The maximum percentage of memory that the compressed
- pool can occupy.
+ pool can occupy.
-The default compressor is lzo, but it can be selected at boot time by setting
-the “compressor” attribute, e.g. zswap.compressor=lzo. It can also be changed
-at runtime using the sysfs "compressor" attribute, e.g.
+The default compressor is lzo, but it can be selected at boot time by
+setting the ``compressor`` attribute, e.g. ``zswap.compressor=lzo``.
+It can also be changed at runtime using the sysfs "compressor"
+attribute, e.g.::
-echo lzo > /sys/module/zswap/parameters/compressor
+ echo lzo > /sys/module/zswap/parameters/compressor
When the zpool and/or compressor parameter is changed at runtime, any existing
compressed pages are not modified; they are left in their own zpool. When a
@@ -106,11 +118,12 @@ compressed length of the page is set to zero and the pattern or same-filled
value is stored.
Same-value filled pages identification feature is enabled by default and can be
-disabled at boot time by setting the "same_filled_pages_enabled" attribute to 0,
-e.g. zswap.same_filled_pages_enabled=0. It can also be enabled and disabled at
-runtime using the sysfs "same_filled_pages_enabled" attribute, e.g.
+disabled at boot time by setting the ``same_filled_pages_enabled`` attribute
+to 0, e.g. ``zswap.same_filled_pages_enabled=0``. It can also be enabled and
+disabled at runtime using the sysfs ``same_filled_pages_enabled``
+attribute, e.g.::
-echo 1 > /sys/module/zswap/parameters/same_filled_pages_enabled
+ echo 1 > /sys/module/zswap/parameters/same_filled_pages_enabled
When zswap same-filled page identification is disabled at runtime, it will stop
checking for the same-value filled pages during store operation. However, the
--
2.7.4
^ permalink raw reply related
* [PATCH 31/32] docs/vm: rename documentation files to .rst
From: Mike Rapoport @ 2018-03-21 19:22 UTC (permalink / raw)
To: Jonathan Corbet
Cc: Andrey Ryabinin, Richard Henderson, Ivan Kokshaysky, Matt Turner,
Tony Luck, Fenghua Yu, Ralf Baechle, James Hogan,
Michael Ellerman, Alexander Viro, linux-kernel, linux-doc,
kasan-dev, linux-alpha, linux-ia64, linux-mips, linuxppc-dev,
linux-fsdevel, linux-mm, Mike Rapoport
In-Reply-To: <1521660168-14372-1-git-send-email-rppt@linux.vnet.ibm.com>
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
---
Documentation/ABI/stable/sysfs-devices-node | 2 +-
.../ABI/testing/sysfs-kernel-mm-hugepages | 2 +-
Documentation/ABI/testing/sysfs-kernel-mm-ksm | 2 +-
Documentation/ABI/testing/sysfs-kernel-slab | 4 +-
Documentation/admin-guide/kernel-parameters.txt | 12 ++---
Documentation/dev-tools/kasan.rst | 2 +-
Documentation/filesystems/proc.txt | 4 +-
Documentation/filesystems/tmpfs.txt | 2 +-
Documentation/sysctl/vm.txt | 6 +--
Documentation/vm/00-INDEX | 58 +++++++++++-----------
Documentation/vm/{active_mm.txt => active_mm.rst} | 0
Documentation/vm/{balance => balance.rst} | 0
.../vm/{cleancache.txt => cleancache.rst} | 0
Documentation/vm/{frontswap.txt => frontswap.rst} | 0
Documentation/vm/{highmem.txt => highmem.rst} | 0
Documentation/vm/{hmm.txt => hmm.rst} | 0
.../{hugetlbfs_reserv.txt => hugetlbfs_reserv.rst} | 0
.../vm/{hugetlbpage.txt => hugetlbpage.rst} | 2 +-
Documentation/vm/{hwpoison.txt => hwpoison.rst} | 2 +-
...le_page_tracking.txt => idle_page_tracking.rst} | 2 +-
Documentation/vm/{ksm.txt => ksm.rst} | 0
.../vm/{mmu_notifier.txt => mmu_notifier.rst} | 0
Documentation/vm/{numa => numa.rst} | 2 +-
...ma_memory_policy.txt => numa_memory_policy.rst} | 0
...commit-accounting => overcommit-accounting.rst} | 0
Documentation/vm/{page_frags => page_frags.rst} | 0
.../vm/{page_migration => page_migration.rst} | 0
.../vm/{page_owner.txt => page_owner.rst} | 0
Documentation/vm/{pagemap.txt => pagemap.rst} | 6 +--
.../{remap_file_pages.txt => remap_file_pages.rst} | 0
Documentation/vm/{slub.txt => slub.rst} | 0
.../vm/{soft-dirty.txt => soft-dirty.rst} | 0
...t_page_table_lock => split_page_table_lock.rst} | 0
Documentation/vm/{swap_numa.txt => swap_numa.rst} | 0
Documentation/vm/{transhuge.txt => transhuge.rst} | 0
.../{unevictable-lru.txt => unevictable-lru.rst} | 0
.../vm/{userfaultfd.txt => userfaultfd.rst} | 0
Documentation/vm/{z3fold.txt => z3fold.rst} | 0
Documentation/vm/{zsmalloc.txt => zsmalloc.rst} | 0
Documentation/vm/{zswap.txt => zswap.rst} | 0
MAINTAINERS | 2 +-
arch/alpha/Kconfig | 2 +-
arch/ia64/Kconfig | 2 +-
arch/mips/Kconfig | 2 +-
arch/powerpc/Kconfig | 2 +-
fs/Kconfig | 2 +-
fs/dax.c | 2 +-
fs/proc/task_mmu.c | 4 +-
include/linux/hmm.h | 2 +-
include/linux/memremap.h | 4 +-
include/linux/mmu_notifier.h | 2 +-
include/linux/sched/mm.h | 4 +-
include/linux/swap.h | 2 +-
mm/Kconfig | 6 +--
mm/cleancache.c | 2 +-
mm/frontswap.c | 2 +-
mm/hmm.c | 2 +-
mm/huge_memory.c | 4 +-
mm/hugetlb.c | 4 +-
mm/ksm.c | 4 +-
mm/mmap.c | 2 +-
mm/rmap.c | 6 +--
mm/util.c | 2 +-
63 files changed, 87 insertions(+), 87 deletions(-)
rename Documentation/vm/{active_mm.txt => active_mm.rst} (100%)
rename Documentation/vm/{balance => balance.rst} (100%)
rename Documentation/vm/{cleancache.txt => cleancache.rst} (100%)
rename Documentation/vm/{frontswap.txt => frontswap.rst} (100%)
rename Documentation/vm/{highmem.txt => highmem.rst} (100%)
rename Documentation/vm/{hmm.txt => hmm.rst} (100%)
rename Documentation/vm/{hugetlbfs_reserv.txt => hugetlbfs_reserv.rst} (100%)
rename Documentation/vm/{hugetlbpage.txt => hugetlbpage.rst} (99%)
rename Documentation/vm/{hwpoison.txt => hwpoison.rst} (99%)
rename Documentation/vm/{idle_page_tracking.txt => idle_page_tracking.rst} (98%)
rename Documentation/vm/{ksm.txt => ksm.rst} (100%)
rename Documentation/vm/{mmu_notifier.txt => mmu_notifier.rst} (100%)
rename Documentation/vm/{numa => numa.rst} (99%)
rename Documentation/vm/{numa_memory_policy.txt => numa_memory_policy.rst} (100%)
rename Documentation/vm/{overcommit-accounting => overcommit-accounting.rst} (100%)
rename Documentation/vm/{page_frags => page_frags.rst} (100%)
rename Documentation/vm/{page_migration => page_migration.rst} (100%)
rename Documentation/vm/{page_owner.txt => page_owner.rst} (100%)
rename Documentation/vm/{pagemap.txt => pagemap.rst} (98%)
rename Documentation/vm/{remap_file_pages.txt => remap_file_pages.rst} (100%)
rename Documentation/vm/{slub.txt => slub.rst} (100%)
rename Documentation/vm/{soft-dirty.txt => soft-dirty.rst} (100%)
rename Documentation/vm/{split_page_table_lock => split_page_table_lock.rst} (100%)
rename Documentation/vm/{swap_numa.txt => swap_numa.rst} (100%)
rename Documentation/vm/{transhuge.txt => transhuge.rst} (100%)
rename Documentation/vm/{unevictable-lru.txt => unevictable-lru.rst} (100%)
rename Documentation/vm/{userfaultfd.txt => userfaultfd.rst} (100%)
rename Documentation/vm/{z3fold.txt => z3fold.rst} (100%)
rename Documentation/vm/{zsmalloc.txt => zsmalloc.rst} (100%)
rename Documentation/vm/{zswap.txt => zswap.rst} (100%)
diff --git a/Documentation/ABI/stable/sysfs-devices-node b/Documentation/ABI/stable/sysfs-devices-node
index 5b2d0f0..b38f4b7 100644
--- a/Documentation/ABI/stable/sysfs-devices-node
+++ b/Documentation/ABI/stable/sysfs-devices-node
@@ -90,4 +90,4 @@ Date: December 2009
Contact: Lee Schermerhorn <lee.schermerhorn@hp.com>
Description:
The node's huge page size control/query attributes.
- See Documentation/vm/hugetlbpage.txt
\ No newline at end of file
+ See Documentation/vm/hugetlbpage.rst
\ No newline at end of file
diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-hugepages b/Documentation/ABI/testing/sysfs-kernel-mm-hugepages
index e21c005..5140b23 100644
--- a/Documentation/ABI/testing/sysfs-kernel-mm-hugepages
+++ b/Documentation/ABI/testing/sysfs-kernel-mm-hugepages
@@ -12,4 +12,4 @@ Description:
free_hugepages
surplus_hugepages
resv_hugepages
- See Documentation/vm/hugetlbpage.txt for details.
+ See Documentation/vm/hugetlbpage.rst for details.
diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-ksm b/Documentation/ABI/testing/sysfs-kernel-mm-ksm
index 73e653e..dfc1324 100644
--- a/Documentation/ABI/testing/sysfs-kernel-mm-ksm
+++ b/Documentation/ABI/testing/sysfs-kernel-mm-ksm
@@ -40,7 +40,7 @@ Description: Kernel Samepage Merging daemon sysfs interface
sleep_millisecs: how many milliseconds ksm should sleep between
scans.
- See Documentation/vm/ksm.txt for more information.
+ See Documentation/vm/ksm.rst for more information.
What: /sys/kernel/mm/ksm/merge_across_nodes
Date: January 2013
diff --git a/Documentation/ABI/testing/sysfs-kernel-slab b/Documentation/ABI/testing/sysfs-kernel-slab
index 2cc0a72..29601d9 100644
--- a/Documentation/ABI/testing/sysfs-kernel-slab
+++ b/Documentation/ABI/testing/sysfs-kernel-slab
@@ -37,7 +37,7 @@ Description:
The alloc_calls file is read-only and lists the kernel code
locations from which allocations for this cache were performed.
The alloc_calls file only contains information if debugging is
- enabled for that cache (see Documentation/vm/slub.txt).
+ enabled for that cache (see Documentation/vm/slub.rst).
What: /sys/kernel/slab/cache/alloc_fastpath
Date: February 2008
@@ -219,7 +219,7 @@ Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
Description:
The free_calls file is read-only and lists the locations of
object frees if slab debugging is enabled (see
- Documentation/vm/slub.txt).
+ Documentation/vm/slub.rst).
What: /sys/kernel/slab/cache/free_fastpath
Date: February 2008
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 1d1d53f..5d6e550 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3887,7 +3887,7 @@
cache (risks via metadata attacks are mostly
unchanged). Debug options disable merging on their
own.
- For more information see Documentation/vm/slub.txt.
+ For more information see Documentation/vm/slub.rst.
slab_max_order= [MM, SLAB]
Determines the maximum allowed order for slabs.
@@ -3901,7 +3901,7 @@
slub_debug can create guard zones around objects and
may poison objects when not in use. Also tracks the
last alloc / free. For more information see
- Documentation/vm/slub.txt.
+ Documentation/vm/slub.rst.
slub_memcg_sysfs= [MM, SLUB]
Determines whether to enable sysfs directories for
@@ -3915,7 +3915,7 @@
Determines the maximum allowed order for slabs.
A high setting may cause OOMs due to memory
fragmentation. For more information see
- Documentation/vm/slub.txt.
+ Documentation/vm/slub.rst.
slub_min_objects= [MM, SLUB]
The minimum number of objects per slab. SLUB will
@@ -3924,12 +3924,12 @@
the number of objects indicated. The higher the number
of objects the smaller the overhead of tracking slabs
and the less frequently locks need to be acquired.
- For more information see Documentation/vm/slub.txt.
+ For more information see Documentation/vm/slub.rst.
slub_min_order= [MM, SLUB]
Determines the minimum page order for slabs. Must be
lower than slub_max_order.
- For more information see Documentation/vm/slub.txt.
+ For more information see Documentation/vm/slub.rst.
slub_nomerge [MM, SLUB]
Same with slab_nomerge. This is supported for legacy.
@@ -4285,7 +4285,7 @@
Format: [always|madvise|never]
Can be used to control the default behavior of the system
with respect to transparent hugepages.
- See Documentation/vm/transhuge.txt for more details.
+ See Documentation/vm/transhuge.rst for more details.
tsc= Disable clocksource stability checks for TSC.
Format: <string>
diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst
index f7a18f2..aabc873 100644
--- a/Documentation/dev-tools/kasan.rst
+++ b/Documentation/dev-tools/kasan.rst
@@ -120,7 +120,7 @@ A typical out of bounds access report looks like this::
The header of the report discribe what kind of bug happened and what kind of
access caused it. It's followed by the description of the accessed slub object
-(see 'SLUB Debug output' section in Documentation/vm/slub.txt for details) and
+(see 'SLUB Debug output' section in Documentation/vm/slub.rst for details) and
the description of the accessed memory page.
In the last section the report shows memory state around the accessed address.
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 2a84bb3..2d3984c 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -515,7 +515,7 @@ guarantees:
The /proc/PID/clear_refs is used to reset the PG_Referenced and ACCESSED/YOUNG
bits on both physical and virtual pages associated with a process, and the
-soft-dirty bit on pte (see Documentation/vm/soft-dirty.txt for details).
+soft-dirty bit on pte (see Documentation/vm/soft-dirty.rst for details).
To clear the bits for all the pages associated with the process
> echo 1 > /proc/PID/clear_refs
@@ -536,7 +536,7 @@ Any other value written to /proc/PID/clear_refs will have no effect.
The /proc/pid/pagemap gives the PFN, which can be used to find the pageflags
using /proc/kpageflags and number of times a page is mapped using
-/proc/kpagecount. For detailed explanation, see Documentation/vm/pagemap.txt.
+/proc/kpagecount. For detailed explanation, see Documentation/vm/pagemap.rst.
The /proc/pid/numa_maps is an extension based on maps, showing the memory
locality and binding policy, as well as the memory usage (in pages) of
diff --git a/Documentation/filesystems/tmpfs.txt b/Documentation/filesystems/tmpfs.txt
index a85355c..627389a 100644
--- a/Documentation/filesystems/tmpfs.txt
+++ b/Documentation/filesystems/tmpfs.txt
@@ -105,7 +105,7 @@ policy for the file will revert to "default" policy.
NUMA memory allocation policies have optional flags that can be used in
conjunction with their modes. These optional flags can be specified
when tmpfs is mounted by appending them to the mode before the NodeList.
-See Documentation/vm/numa_memory_policy.txt for a list of all available
+See Documentation/vm/numa_memory_policy.rst for a list of all available
memory allocation policy mode flags and their effect on memory policy.
=static is equivalent to MPOL_F_STATIC_NODES
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index ff234d2..ef581a9 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -516,7 +516,7 @@ nr_hugepages
Change the minimum size of the hugepage pool.
-See Documentation/vm/hugetlbpage.txt
+See Documentation/vm/hugetlbpage.rst
==============================================================
@@ -525,7 +525,7 @@ nr_overcommit_hugepages
Change the maximum size of the hugepage pool. The maximum is
nr_hugepages + nr_overcommit_hugepages.
-See Documentation/vm/hugetlbpage.txt
+See Documentation/vm/hugetlbpage.rst
==============================================================
@@ -668,7 +668,7 @@ and don't use much of it.
The default value is 0.
-See Documentation/vm/overcommit-accounting and
+See Documentation/vm/overcommit-accounting.rst and
mm/mmap.c::__vm_enough_memory() for more information.
==============================================================
diff --git a/Documentation/vm/00-INDEX b/Documentation/vm/00-INDEX
index 0278f2c..cda564d 100644
--- a/Documentation/vm/00-INDEX
+++ b/Documentation/vm/00-INDEX
@@ -1,62 +1,62 @@
00-INDEX
- this file.
-active_mm.txt
+active_mm.rst
- An explanation from Linus about tsk->active_mm vs tsk->mm.
-balance
+balance.rst
- various information on memory balancing.
-cleancache.txt
+cleancache.rst
- Intro to cleancache and page-granularity victim cache.
-frontswap.txt
+frontswap.rst
- Outline frontswap, part of the transcendent memory frontend.
-highmem.txt
+highmem.rst
- Outline of highmem and common issues.
-hmm.txt
+hmm.rst
- Documentation of heterogeneous memory management
-hugetlbpage.txt
+hugetlbpage.rst
- a brief summary of hugetlbpage support in the Linux kernel.
-hugetlbfs_reserv.txt
+hugetlbfs_reserv.rst
- A brief overview of hugetlbfs reservation design/implementation.
-hwpoison.txt
+hwpoison.rst
- explains what hwpoison is
-idle_page_tracking.txt
+idle_page_tracking.rst
- description of the idle page tracking feature.
-ksm.txt
+ksm.rst
- how to use the Kernel Samepage Merging feature.
-mmu_notifier.txt
+mmu_notifier.rst
- a note about clearing pte/pmd and mmu notifications
-numa
+numa.rst
- information about NUMA specific code in the Linux vm.
-numa_memory_policy.txt
+numa_memory_policy.rst
- documentation of concepts and APIs of the 2.6 memory policy support.
-overcommit-accounting
+overcommit-accounting.rst
- description of the Linux kernels overcommit handling modes.
-page_frags
+page_frags.rst
- description of page fragments allocator
-page_migration
+page_migration.rst
- description of page migration in NUMA systems.
-pagemap.txt
+pagemap.rst
- pagemap, from the userspace perspective
-page_owner.txt
+page_owner.rst
- tracking about who allocated each page
-remap_file_pages.txt
+remap_file_pages.rst
- a note about remap_file_pages() system call
-slub.txt
+slub.rst
- a short users guide for SLUB.
-soft-dirty.txt
+soft-dirty.rst
- short explanation for soft-dirty PTEs
-split_page_table_lock
+split_page_table_lock.rst
- Separate per-table lock to improve scalability of the old page_table_lock.
-swap_numa.txt
+swap_numa.rst
- automatic binding of swap device to numa node
-transhuge.txt
+transhuge.rst
- Transparent Hugepage Support, alternative way of using hugepages.
-unevictable-lru.txt
+unevictable-lru.rst
- Unevictable LRU infrastructure
-userfaultfd.txt
+userfaultfd.rst
- description of userfaultfd system call
z3fold.txt
- outline of z3fold allocator for storing compressed pages
-zsmalloc.txt
+zsmalloc.rst
- outline of zsmalloc allocator for storing compressed pages
-zswap.txt
+zswap.rst
- Intro to compressed cache for swap pages
diff --git a/Documentation/vm/active_mm.txt b/Documentation/vm/active_mm.rst
similarity index 100%
rename from Documentation/vm/active_mm.txt
rename to Documentation/vm/active_mm.rst
diff --git a/Documentation/vm/balance b/Documentation/vm/balance.rst
similarity index 100%
rename from Documentation/vm/balance
rename to Documentation/vm/balance.rst
diff --git a/Documentation/vm/cleancache.txt b/Documentation/vm/cleancache.rst
similarity index 100%
rename from Documentation/vm/cleancache.txt
rename to Documentation/vm/cleancache.rst
diff --git a/Documentation/vm/frontswap.txt b/Documentation/vm/frontswap.rst
similarity index 100%
rename from Documentation/vm/frontswap.txt
rename to Documentation/vm/frontswap.rst
diff --git a/Documentation/vm/highmem.txt b/Documentation/vm/highmem.rst
similarity index 100%
rename from Documentation/vm/highmem.txt
rename to Documentation/vm/highmem.rst
diff --git a/Documentation/vm/hmm.txt b/Documentation/vm/hmm.rst
similarity index 100%
rename from Documentation/vm/hmm.txt
rename to Documentation/vm/hmm.rst
diff --git a/Documentation/vm/hugetlbfs_reserv.txt b/Documentation/vm/hugetlbfs_reserv.rst
similarity index 100%
rename from Documentation/vm/hugetlbfs_reserv.txt
rename to Documentation/vm/hugetlbfs_reserv.rst
diff --git a/Documentation/vm/hugetlbpage.txt b/Documentation/vm/hugetlbpage.rst
similarity index 99%
rename from Documentation/vm/hugetlbpage.txt
rename to Documentation/vm/hugetlbpage.rst
index 3bb0d99..a5da14b 100644
--- a/Documentation/vm/hugetlbpage.txt
+++ b/Documentation/vm/hugetlbpage.rst
@@ -217,7 +217,7 @@ When adjusting the persistent hugepage count via ``nr_hugepages_mempolicy``, any
memory policy mode--bind, preferred, local or interleave--may be used. The
resulting effect on persistent huge page allocation is as follows:
-#. Regardless of mempolicy mode [see Documentation/vm/numa_memory_policy.txt],
+#. Regardless of mempolicy mode [see Documentation/vm/numa_memory_policy.rst],
persistent huge pages will be distributed across the node or nodes
specified in the mempolicy as if "interleave" had been specified.
However, if a node in the policy does not contain sufficient contiguous
diff --git a/Documentation/vm/hwpoison.txt b/Documentation/vm/hwpoison.rst
similarity index 99%
rename from Documentation/vm/hwpoison.txt
rename to Documentation/vm/hwpoison.rst
index b1a8c24..070aa1e 100644
--- a/Documentation/vm/hwpoison.txt
+++ b/Documentation/vm/hwpoison.rst
@@ -155,7 +155,7 @@ Testing
value). This allows stress testing of many kinds of
pages. The page_flags are the same as in /proc/kpageflags. The
flag bits are defined in include/linux/kernel-page-flags.h and
- documented in Documentation/vm/pagemap.txt
+ documented in Documentation/vm/pagemap.rst
* Architecture specific MCE injector
diff --git a/Documentation/vm/idle_page_tracking.txt b/Documentation/vm/idle_page_tracking.rst
similarity index 98%
rename from Documentation/vm/idle_page_tracking.txt
rename to Documentation/vm/idle_page_tracking.rst
index 9cbe6f8..d1c4609 100644
--- a/Documentation/vm/idle_page_tracking.txt
+++ b/Documentation/vm/idle_page_tracking.rst
@@ -65,7 +65,7 @@ workload one should:
are not reclaimable, he or she can filter them out using
``/proc/kpageflags``.
-See Documentation/vm/pagemap.txt for more information about
+See Documentation/vm/pagemap.rst for more information about
``/proc/pid/pagemap``, ``/proc/kpageflags``, and ``/proc/kpagecgroup``.
.. _impl_details:
diff --git a/Documentation/vm/ksm.txt b/Documentation/vm/ksm.rst
similarity index 100%
rename from Documentation/vm/ksm.txt
rename to Documentation/vm/ksm.rst
diff --git a/Documentation/vm/mmu_notifier.txt b/Documentation/vm/mmu_notifier.rst
similarity index 100%
rename from Documentation/vm/mmu_notifier.txt
rename to Documentation/vm/mmu_notifier.rst
diff --git a/Documentation/vm/numa b/Documentation/vm/numa.rst
similarity index 99%
rename from Documentation/vm/numa
rename to Documentation/vm/numa.rst
index c81e7c5..aada84b 100644
--- a/Documentation/vm/numa
+++ b/Documentation/vm/numa.rst
@@ -110,7 +110,7 @@ to improve NUMA locality using various CPU affinity command line interfaces,
such as taskset(1) and numactl(1), and program interfaces such as
sched_setaffinity(2). Further, one can modify the kernel's default local
allocation behavior using Linux NUMA memory policy.
-[see Documentation/vm/numa_memory_policy.txt.]
+[see Documentation/vm/numa_memory_policy.rst.]
System administrators can restrict the CPUs and nodes' memories that a non-
privileged user can specify in the scheduling or NUMA commands and functions
diff --git a/Documentation/vm/numa_memory_policy.txt b/Documentation/vm/numa_memory_policy.rst
similarity index 100%
rename from Documentation/vm/numa_memory_policy.txt
rename to Documentation/vm/numa_memory_policy.rst
diff --git a/Documentation/vm/overcommit-accounting b/Documentation/vm/overcommit-accounting.rst
similarity index 100%
rename from Documentation/vm/overcommit-accounting
rename to Documentation/vm/overcommit-accounting.rst
diff --git a/Documentation/vm/page_frags b/Documentation/vm/page_frags.rst
similarity index 100%
rename from Documentation/vm/page_frags
rename to Documentation/vm/page_frags.rst
diff --git a/Documentation/vm/page_migration b/Documentation/vm/page_migration.rst
similarity index 100%
rename from Documentation/vm/page_migration
rename to Documentation/vm/page_migration.rst
diff --git a/Documentation/vm/page_owner.txt b/Documentation/vm/page_owner.rst
similarity index 100%
rename from Documentation/vm/page_owner.txt
rename to Documentation/vm/page_owner.rst
diff --git a/Documentation/vm/pagemap.txt b/Documentation/vm/pagemap.rst
similarity index 98%
rename from Documentation/vm/pagemap.txt
rename to Documentation/vm/pagemap.rst
index bd6d717..d54b4bf 100644
--- a/Documentation/vm/pagemap.txt
+++ b/Documentation/vm/pagemap.rst
@@ -18,7 +18,7 @@ There are four components to pagemap:
* Bits 0-54 page frame number (PFN) if present
* Bits 0-4 swap type if swapped
* Bits 5-54 swap offset if swapped
- * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.txt)
+ * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.rst)
* Bit 56 page exclusively mapped (since 4.2)
* Bits 57-60 zero
* Bit 61 page is file-page or shared-anon (since 3.5)
@@ -97,7 +97,7 @@ Short descriptions to the page flags:
A compound page with order N consists of 2^N physically contiguous pages.
A compound page with order 2 takes the form of "HTTT", where H donates its
head page and T donates its tail page(s). The major consumers of compound
- pages are hugeTLB pages (Documentation/vm/hugetlbpage.txt), the SLUB etc.
+ pages are hugeTLB pages (Documentation/vm/hugetlbpage.rst), the SLUB etc.
memory allocators and various device drivers. However in this interface,
only huge/giga pages are made visible to end users.
16 - COMPOUND_TAIL
@@ -118,7 +118,7 @@ Short descriptions to the page flags:
zero page for pfn_zero or huge_zero page
25 - IDLE
page has not been accessed since it was marked idle (see
- Documentation/vm/idle_page_tracking.txt). Note that this flag may be
+ Documentation/vm/idle_page_tracking.rst). Note that this flag may be
stale in case the page was accessed via a PTE. To make sure the flag
is up-to-date one has to read ``/sys/kernel/mm/page_idle/bitmap`` first.
diff --git a/Documentation/vm/remap_file_pages.txt b/Documentation/vm/remap_file_pages.rst
similarity index 100%
rename from Documentation/vm/remap_file_pages.txt
rename to Documentation/vm/remap_file_pages.rst
diff --git a/Documentation/vm/slub.txt b/Documentation/vm/slub.rst
similarity index 100%
rename from Documentation/vm/slub.txt
rename to Documentation/vm/slub.rst
diff --git a/Documentation/vm/soft-dirty.txt b/Documentation/vm/soft-dirty.rst
similarity index 100%
rename from Documentation/vm/soft-dirty.txt
rename to Documentation/vm/soft-dirty.rst
diff --git a/Documentation/vm/split_page_table_lock b/Documentation/vm/split_page_table_lock.rst
similarity index 100%
rename from Documentation/vm/split_page_table_lock
rename to Documentation/vm/split_page_table_lock.rst
diff --git a/Documentation/vm/swap_numa.txt b/Documentation/vm/swap_numa.rst
similarity index 100%
rename from Documentation/vm/swap_numa.txt
rename to Documentation/vm/swap_numa.rst
diff --git a/Documentation/vm/transhuge.txt b/Documentation/vm/transhuge.rst
similarity index 100%
rename from Documentation/vm/transhuge.txt
rename to Documentation/vm/transhuge.rst
diff --git a/Documentation/vm/unevictable-lru.txt b/Documentation/vm/unevictable-lru.rst
similarity index 100%
rename from Documentation/vm/unevictable-lru.txt
rename to Documentation/vm/unevictable-lru.rst
diff --git a/Documentation/vm/userfaultfd.txt b/Documentation/vm/userfaultfd.rst
similarity index 100%
rename from Documentation/vm/userfaultfd.txt
rename to Documentation/vm/userfaultfd.rst
diff --git a/Documentation/vm/z3fold.txt b/Documentation/vm/z3fold.rst
similarity index 100%
rename from Documentation/vm/z3fold.txt
rename to Documentation/vm/z3fold.rst
diff --git a/Documentation/vm/zsmalloc.txt b/Documentation/vm/zsmalloc.rst
similarity index 100%
rename from Documentation/vm/zsmalloc.txt
rename to Documentation/vm/zsmalloc.rst
diff --git a/Documentation/vm/zswap.txt b/Documentation/vm/zswap.rst
similarity index 100%
rename from Documentation/vm/zswap.txt
rename to Documentation/vm/zswap.rst
diff --git a/MAINTAINERS b/MAINTAINERS
index 4e62756..9dcf431 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15431,7 +15431,7 @@ L: linux-mm@kvack.org
S: Maintained
F: mm/zsmalloc.c
F: include/linux/zsmalloc.h
-F: Documentation/vm/zsmalloc.txt
+F: Documentation/vm/zsmalloc.rst
ZSWAP COMPRESSED SWAP CACHING
M: Seth Jennings <sjenning@redhat.com>
diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index e96adcb..f53e506 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -584,7 +584,7 @@ config ARCH_DISCONTIGMEM_ENABLE
Say Y to support efficient handling of discontiguous physical memory,
for architectures which are either NUMA (Non-Uniform Memory Access)
or have huge holes in the physical address space for other reasons.
- See <file:Documentation/vm/numa> for more.
+ See <file:Documentation/vm/numa.rst> for more.
source "mm/Kconfig"
diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index bbe12a0..3ac9bf4 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -397,7 +397,7 @@ config ARCH_DISCONTIGMEM_ENABLE
Say Y to support efficient handling of discontiguous physical memory,
for architectures which are either NUMA (Non-Uniform Memory Access)
or have huge holes in the physical address space for other reasons.
- See <file:Documentation/vm/numa> for more.
+ See <file:Documentation/vm/numa.rst> for more.
config ARCH_FLATMEM_ENABLE
def_bool y
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 8128c3b..4562810 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -2551,7 +2551,7 @@ config ARCH_DISCONTIGMEM_ENABLE
Say Y to support efficient handling of discontiguous physical memory,
for architectures which are either NUMA (Non-Uniform Memory Access)
or have huge holes in the physical address space for other reasons.
- See <file:Documentation/vm/numa> for more.
+ See <file:Documentation/vm/numa.rst> for more.
config ARCH_SPARSEMEM_ENABLE
bool
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 73ce5dd..f8c0f10 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -880,7 +880,7 @@ config PPC_MEM_KEYS
page-based protections, but without requiring modification of the
page tables when an application changes protection domains.
- For details, see Documentation/vm/protection-keys.txt
+ For details, see Documentation/vm/protection-keys.rst
If unsure, say y.
diff --git a/fs/Kconfig b/fs/Kconfig
index bc821a8..ba53dc2 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -196,7 +196,7 @@ config HUGETLBFS
help
hugetlbfs is a filesystem backing for HugeTLB pages, based on
ramfs. For architectures that support it, say Y here and read
- <file:Documentation/vm/hugetlbpage.txt> for details.
+ <file:Documentation/vm/hugetlbpage.rst> for details.
If unsure, say N.
diff --git a/fs/dax.c b/fs/dax.c
index 0276df9..0eb65c3 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -618,7 +618,7 @@ static void dax_mapping_entry_mkclean(struct address_space *mapping,
* downgrading page table protection not changing it to point
* to a new page.
*
- * See Documentation/vm/mmu_notifier.txt
+ * See Documentation/vm/mmu_notifier.rst
*/
if (pmdp) {
#ifdef CONFIG_FS_DAX_PMD
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index ec6d298..91d14c4a 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -956,7 +956,7 @@ static inline void clear_soft_dirty(struct vm_area_struct *vma,
/*
* The soft-dirty tracker uses #PF-s to catch writes
* to pages, so write-protect the pte as well. See the
- * Documentation/vm/soft-dirty.txt for full description
+ * Documentation/vm/soft-dirty.rst for full description
* of how soft-dirty works.
*/
pte_t ptent = *pte;
@@ -1436,7 +1436,7 @@ static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
* Bits 0-54 page frame number (PFN) if present
* Bits 0-4 swap type if swapped
* Bits 5-54 swap offset if swapped
- * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.txt)
+ * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.rst)
* Bit 56 page exclusively mapped
* Bits 57-60 zero
* Bit 61 page is file-page or shared-anon
diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index 325017a..77be87c 100644
--- a/include/linux/hmm.h
+++ b/include/linux/hmm.h
@@ -16,7 +16,7 @@
/*
* Heterogeneous Memory Management (HMM)
*
- * See Documentation/vm/hmm.txt for reasons and overview of what HMM is and it
+ * See Documentation/vm/hmm.rst for reasons and overview of what HMM is and it
* is for. Here we focus on the HMM API description, with some explanation of
* the underlying implementation.
*
diff --git a/include/linux/memremap.h b/include/linux/memremap.h
index 7b4899c..74ea5e2 100644
--- a/include/linux/memremap.h
+++ b/include/linux/memremap.h
@@ -45,7 +45,7 @@ struct vmem_altmap {
* must be treated as an opaque object, rather than a "normal" struct page.
*
* A more complete discussion of unaddressable memory may be found in
- * include/linux/hmm.h and Documentation/vm/hmm.txt.
+ * include/linux/hmm.h and Documentation/vm/hmm.rst.
*
* MEMORY_DEVICE_PUBLIC:
* Device memory that is cache coherent from device and CPU point of view. This
@@ -67,7 +67,7 @@ enum memory_type {
* page_free()
*
* Additional notes about MEMORY_DEVICE_PRIVATE may be found in
- * include/linux/hmm.h and Documentation/vm/hmm.txt. There is also a brief
+ * include/linux/hmm.h and Documentation/vm/hmm.rst. There is also a brief
* explanation in include/linux/memory_hotplug.h.
*
* The page_fault() callback must migrate page back, from device memory to
diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h
index 2d07a1e..392e6af 100644
--- a/include/linux/mmu_notifier.h
+++ b/include/linux/mmu_notifier.h
@@ -174,7 +174,7 @@ struct mmu_notifier_ops {
* invalidate_range_start()/end() notifiers, as
* invalidate_range() alread catches the points in time when an
* external TLB range needs to be flushed. For more in depth
- * discussion on this see Documentation/vm/mmu_notifier.txt
+ * discussion on this see Documentation/vm/mmu_notifier.rst
*
* Note that this function might be called with just a sub-range
* of what was passed to invalidate_range_start()/end(), if
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
index 9806184..5837192 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -28,7 +28,7 @@ extern struct mm_struct *mm_alloc(void);
*
* Use mmdrop() to release the reference acquired by mmgrab().
*
- * See also <Documentation/vm/active_mm.txt> for an in-depth explanation
+ * See also <Documentation/vm/active_mm.rst> for an in-depth explanation
* of &mm_struct.mm_count vs &mm_struct.mm_users.
*/
static inline void mmgrab(struct mm_struct *mm)
@@ -62,7 +62,7 @@ static inline void mmdrop(struct mm_struct *mm)
*
* Use mmput() to release the reference acquired by mmget().
*
- * See also <Documentation/vm/active_mm.txt> for an in-depth explanation
+ * See also <Documentation/vm/active_mm.rst> for an in-depth explanation
* of &mm_struct.mm_count vs &mm_struct.mm_users.
*/
static inline void mmget(struct mm_struct *mm)
diff --git a/include/linux/swap.h b/include/linux/swap.h
index a1a3f4e..4598fc7 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -53,7 +53,7 @@ static inline int current_is_kswapd(void)
/*
* Unaddressable device memory support. See include/linux/hmm.h and
- * Documentation/vm/hmm.txt. Short description is we need struct pages for
+ * Documentation/vm/hmm.rst. Short description is we need struct pages for
* device memory that is unaddressable (inaccessible) by CPU, so that we can
* migrate part of a process memory to device memory.
*
diff --git a/mm/Kconfig b/mm/Kconfig
index c782e8f..b9f0421 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -312,7 +312,7 @@ config KSM
the many instances by a single page with that content, so
saving memory until one or another app needs to modify the content.
Recommended for use with KVM, or with other duplicative applications.
- See Documentation/vm/ksm.txt for more information: KSM is inactive
+ See Documentation/vm/ksm.rst for more information: KSM is inactive
until a program has madvised that an area is MADV_MERGEABLE, and
root has set /sys/kernel/mm/ksm/run to 1 (if CONFIG_SYSFS is set).
@@ -537,7 +537,7 @@ config MEM_SOFT_DIRTY
into a page just as regular dirty bit, but unlike the latter
it can be cleared by hands.
- See Documentation/vm/soft-dirty.txt for more details.
+ See Documentation/vm/soft-dirty.rst for more details.
config ZSWAP
bool "Compressed cache for swap pages (EXPERIMENTAL)"
@@ -664,7 +664,7 @@ config IDLE_PAGE_TRACKING
be useful to tune memory cgroup limits and/or for job placement
within a compute cluster.
- See Documentation/vm/idle_page_tracking.txt for more details.
+ See Documentation/vm/idle_page_tracking.rst for more details.
# arch_add_memory() comprehends device memory
config ARCH_HAS_ZONE_DEVICE
diff --git a/mm/cleancache.c b/mm/cleancache.c
index f7b9fdc..126548b 100644
--- a/mm/cleancache.c
+++ b/mm/cleancache.c
@@ -3,7 +3,7 @@
*
* This code provides the generic "frontend" layer to call a matching
* "backend" driver implementation of cleancache. See
- * Documentation/vm/cleancache.txt for more information.
+ * Documentation/vm/cleancache.rst for more information.
*
* Copyright (C) 2009-2010 Oracle Corp. All rights reserved.
* Author: Dan Magenheimer
diff --git a/mm/frontswap.c b/mm/frontswap.c
index fec8b50..4f5476a 100644
--- a/mm/frontswap.c
+++ b/mm/frontswap.c
@@ -3,7 +3,7 @@
*
* This code provides the generic "frontend" layer to call a matching
* "backend" driver implementation of frontswap. See
- * Documentation/vm/frontswap.txt for more information.
+ * Documentation/vm/frontswap.rst for more information.
*
* Copyright (C) 2009-2012 Oracle Corp. All rights reserved.
* Author: Dan Magenheimer
diff --git a/mm/hmm.c b/mm/hmm.c
index 320545b98..af176c6 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -37,7 +37,7 @@
#if defined(CONFIG_DEVICE_PRIVATE) || defined(CONFIG_DEVICE_PUBLIC)
/*
- * Device private memory see HMM (Documentation/vm/hmm.txt) or hmm.h
+ * Device private memory see HMM (Documentation/vm/hmm.rst) or hmm.h
*/
DEFINE_STATIC_KEY_FALSE(device_private_key);
EXPORT_SYMBOL(device_private_key);
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 87ab9b8..6d59116 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1185,7 +1185,7 @@ static int do_huge_pmd_wp_page_fallback(struct vm_fault *vmf, pmd_t orig_pmd,
* mmu_notifier_invalidate_range_end() happens which can lead to a
* device seeing memory write in different order than CPU.
*
- * See Documentation/vm/mmu_notifier.txt
+ * See Documentation/vm/mmu_notifier.rst
*/
pmdp_huge_clear_flush_notify(vma, haddr, vmf->pmd);
@@ -2037,7 +2037,7 @@ static void __split_huge_zero_page_pmd(struct vm_area_struct *vma,
* replacing a zero pmd write protected page with a zero pte write
* protected page.
*
- * See Documentation/vm/mmu_notifier.txt
+ * See Documentation/vm/mmu_notifier.rst
*/
pmdp_huge_clear_flush(vma, haddr, pmd);
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index a963f20..1e47698 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3289,7 +3289,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
* table protection not changing it to point
* to a new page.
*
- * See Documentation/vm/mmu_notifier.txt
+ * See Documentation/vm/mmu_notifier.rst
*/
huge_ptep_set_wrprotect(src, addr, src_pte);
}
@@ -4355,7 +4355,7 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
* No need to call mmu_notifier_invalidate_range() we are downgrading
* page table protection not changing it to point to a new page.
*
- * See Documentation/vm/mmu_notifier.txt
+ * See Documentation/vm/mmu_notifier.rst
*/
i_mmap_unlock_write(vma->vm_file->f_mapping);
mmu_notifier_invalidate_range_end(mm, start, end);
diff --git a/mm/ksm.c b/mm/ksm.c
index 293721f..0b88698 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1049,7 +1049,7 @@ static int write_protect_page(struct vm_area_struct *vma, struct page *page,
* No need to notify as we are downgrading page table to read
* only not changing it to point to a new page.
*
- * See Documentation/vm/mmu_notifier.txt
+ * See Documentation/vm/mmu_notifier.rst
*/
entry = ptep_clear_flush(vma, pvmw.address, pvmw.pte);
/*
@@ -1138,7 +1138,7 @@ static int replace_page(struct vm_area_struct *vma, struct page *page,
* No need to notify as we are replacing a read only page with another
* read only page with the same content.
*
- * See Documentation/vm/mmu_notifier.txt
+ * See Documentation/vm/mmu_notifier.rst
*/
ptep_clear_flush(vma, addr, ptep);
set_pte_at_notify(mm, addr, ptep, newpte);
diff --git a/mm/mmap.c b/mm/mmap.c
index 9efdc021..39fc51d 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2769,7 +2769,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
unsigned long ret = -EINVAL;
struct file *file;
- pr_warn_once("%s (%d) uses deprecated remap_file_pages() syscall. See Documentation/vm/remap_file_pages.txt.\n",
+ pr_warn_once("%s (%d) uses deprecated remap_file_pages() syscall. See Documentation/vm/remap_file_pages.rst.\n",
current->comm, current->pid);
if (prot)
diff --git a/mm/rmap.c b/mm/rmap.c
index 47db27f..854b703 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -942,7 +942,7 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma,
* downgrading page table protection not changing it to point
* to a new page.
*
- * See Documentation/vm/mmu_notifier.txt
+ * See Documentation/vm/mmu_notifier.rst
*/
if (ret)
(*cleaned)++;
@@ -1587,7 +1587,7 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
* point at new page while a device still is using this
* page.
*
- * See Documentation/vm/mmu_notifier.txt
+ * See Documentation/vm/mmu_notifier.rst
*/
dec_mm_counter(mm, mm_counter_file(page));
}
@@ -1597,7 +1597,7 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
* done above for all cases requiring it to happen under page
* table lock before mmu_notifier_invalidate_range_end()
*
- * See Documentation/vm/mmu_notifier.txt
+ * See Documentation/vm/mmu_notifier.rst
*/
page_remove_rmap(subpage, PageHuge(page));
put_page(page);
diff --git a/mm/util.c b/mm/util.c
index c125050..e857c80 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -609,7 +609,7 @@ EXPORT_SYMBOL_GPL(vm_memory_committed);
* succeed and -ENOMEM implies there is not.
*
* We currently support three overcommit policies, which are set via the
- * vm.overcommit_memory sysctl. See Documentation/vm/overcommit-accounting
+ * vm.overcommit_memory sysctl. See Documentation/vm/overcommit-accounting.rst
*
* Strict overcommit modes added 2002 Feb 26 by Alan Cox.
* Additional code 2002 Jul 20 by Robert Love.
--
2.7.4
^ permalink raw reply related
* [PATCH 32/32] docs/vm: add index.rst and link MM documentation to top level index
From: Mike Rapoport @ 2018-03-21 19:22 UTC (permalink / raw)
To: Jonathan Corbet
Cc: Andrey Ryabinin, Richard Henderson, Ivan Kokshaysky, Matt Turner,
Tony Luck, Fenghua Yu, Ralf Baechle, James Hogan,
Michael Ellerman, Alexander Viro, linux-kernel, linux-doc,
kasan-dev, linux-alpha, linux-ia64, linux-mips, linuxppc-dev,
linux-fsdevel, linux-mm, Mike Rapoport
In-Reply-To: <1521660168-14372-1-git-send-email-rppt@linux.vnet.ibm.com>
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
---
Documentation/index.rst | 3 ++-
Documentation/vm/conf.py | 10 +++++++++
Documentation/vm/index.rst | 56 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 68 insertions(+), 1 deletion(-)
create mode 100644 Documentation/vm/conf.py
create mode 100644 Documentation/vm/index.rst
diff --git a/Documentation/index.rst b/Documentation/index.rst
index ef5080c..cc4a098 100644
--- a/Documentation/index.rst
+++ b/Documentation/index.rst
@@ -45,7 +45,7 @@ the kernel interface as seen by application developers.
.. toctree::
:maxdepth: 2
- userspace-api/index
+ userspace-api/index
Introduction to kernel development
@@ -88,6 +88,7 @@ needed).
sound/index
crypto/index
filesystems/index
+ vm/index
Architecture-specific documentation
-----------------------------------
diff --git a/Documentation/vm/conf.py b/Documentation/vm/conf.py
new file mode 100644
index 0000000..3b0b601
--- /dev/null
+++ b/Documentation/vm/conf.py
@@ -0,0 +1,10 @@
+# -*- coding: utf-8; mode: python -*-
+
+project = "Linux Memory Management Documentation"
+
+tags.add("subproject")
+
+latex_documents = [
+ ('index', 'memory-management.tex', project,
+ 'The kernel development community', 'manual'),
+]
diff --git a/Documentation/vm/index.rst b/Documentation/vm/index.rst
new file mode 100644
index 0000000..6c45142
--- /dev/null
+++ b/Documentation/vm/index.rst
@@ -0,0 +1,56 @@
+=====================================
+Linux Memory Management Documentation
+=====================================
+
+This is a collection of documents about Linux memory management (mm) subsystem.
+
+User guides for MM features
+===========================
+
+The following documents provide guides for controlling and tuning
+various features of the Linux memory management
+
+.. toctree::
+ :maxdepth: 1
+
+ hugetlbpage
+ idle_page_tracking
+ ksm
+ numa_memory_policy
+ pagemap
+ transhuge
+ soft-dirty
+ swap_numa
+ userfaultfd
+ zswap
+
+Kernel developers MM documentation
+==================================
+
+The below documents describe MM internals with different level of
+details ranging from notes and mailing list responses to elaborate
+descriptions of data structures and algorithms.
+
+.. toctree::
+ :maxdepth: 1
+
+ active_mm
+ balance
+ cleancache
+ frontswap
+ highmem
+ hmm
+ hwpoison
+ hugetlbfs_reserv
+ mmu_notifier
+ numa
+ overcommit-accounting
+ page_migration
+ page_frags
+ page_owner
+ remap_file_pages
+ slub
+ split_page_table_lock
+ unevictable-lru
+ z3fold
+ zsmalloc
--
2.7.4
^ permalink raw reply related
* DMA Mapping Error in ppc64
From: Jared Bents @ 2018-03-21 21:00 UTC (permalink / raw)
To: linuxppc-dev
Hi all,
Apologies for the amount of information but we've been debugging this
for a while and I wanted to get what we are seeing captured as much as
possible. We are a T1042 processor and have a total 8GB DDR and our
kernel version is fsl-sdk-v2.0-1703 (linux v4.1.35) as that is the
latest version supplied by NXP.
A while ago we ported from 32 bit to 64 bit. Everything continued to
work except the ath10k module we have. So as a first step, we checked
to see if an ath9k module also failed to work and it was also no
longer working. The ath10k is working fine on a 32 bit system but
it's not working on 64 bit system as we are getting dma mapping errors
when trying to initialize the wifi modules.
pci_bus 0002:01: bus scan returning with max=01
pci_bus 0002:01: busn_res: [bus 01] end is updated to 01
pci_bus 0002:00: bus scan returning with max=01
ath10k_pci 0000:01:00.0: unable to get target info from device
ath10k_pci 0000:01:00.0: could not get target info (-5)
ath10k_pci 0000:01:00.0: could not probe fw (-5)
ath10k_pci 0001:01:00.0: Direct firmware load for
ath10k/cal-pci-0001:01:00.0.bin failed with error -2
First, we have tried the mainline kernel (v4.15) to see if that would
fix the issue, it did not. So I made a patch for the ath10k driver to
restrict to just GFP_DMA areas when allocating memory or creating
sk_buffs and have attached it. The ath10k wifi modules now initialize
correctly but when I try to connect them and send traffic, they get a
DMA mapping error from the sk_buff that it receives from elsewhere in
the kernel. So while the driver appears to be fixable with the patch,
the modules are still unusable due to data being sent to the driver
when ath10k_tx is called and it tries to dma map with the provided
skb. Also, according to the ath10k mailing list, GFP_DMA is not
supposed to be used in general. The error below is the same sort of
dma mapping error that is seen when initializing the modules without
the patch to OR with GFP_DMA.
ath10k_pci 0001:01:00.0: failed to transmit packet, dropping: -5
We asked on the ath10k mailing list if anyone else is having this
problem and no one else seems to have the issue but they are using
different architectures (ARM or X86). As a result, it does not seem to
be a driver issue to us but something within the PowerPC arch. So we
dug a little deeper to try to find what addresses being mapped are
working and what address being mapped are not working.
We found that when the virtual address of data pointer (a member of
sk_buff) is above ~3.7 GB RAM address range then return address from
dma_map_single API is failed to validate in dma_mapping_error
function.
We also noticed that in a 64bit machine sometimes ping is working and
because of the virtual address is under ~3.7GAM RAM address range. So
if we set mem=2048M in the bootargs, the ath10k module works
perfectly, however this isn't a real solution since it cuts our
available RAM from 8GB to 2GB.
Any information that could help us resolve this issue would be greatly
appreciated.
Thank you,
Jared
^ permalink raw reply
* [trivial PATCH V2] treewide: Align function definition open/close braces
From: Joe Perches @ 2018-03-21 22:09 UTC (permalink / raw)
To: Andrew Morton, Will Deacon, Peter Zijlstra, Boqun Feng,
Rafael J. Wysocki, Len Brown, Zhang Rui, Sathya Prakash,
Chaitra P B, Suganath Prabu Subramani, Manish Chopra, Rahul Verma,
Dept-GELinuxNICDev, QCA ath9k Development, Corentin Chary,
Darren Hart, Andy Shevchenko, Alessandro Zummo, Alexandre Belloni,
Adaptec OEM Raid Solutions, James E.J. Bottomley,
Martin K. Petersen, Matthew Wilcox, Jeff Layton, J. Bruce Fields,
Alexander Viro, Mark Fasheh, Joel Becker, Darrick J. Wong,
linux-xfs, Paul Moore, Eric Paris, Steven Rostedt, Timur Tabi,
Nicolin Chen, Xiubo Li, Fabio Estevam, Jiri Kosina
Cc: Thomas Gleixner, H. Peter Anvin, x86, Alex Deucher,
Christian König, David (ChunMing) Zhou, David Airlie,
Mauro Carvalho Chehab, Kalle Valo, Liam Girdwood, Mark Brown,
Jaroslav Kysela, Takashi Iwai, linux-kernel, linux-acpi, amd-gfx,
dri-devel, linux-media, MPT-FusionLinux.pdl, linux-scsi, netdev,
linux-wireless, acpi4asus-user, platform-driver-x86, linux-rtc,
linux-fsdevel, ocfs2-devel, linux-audit, alsa-devel, linuxppc-dev
Some functions definitions have either the initial open brace and/or
the closing brace outside of column 1.
Move those braces to column 1.
This allows various function analyzers like gnu complexity to work
properly for these modified functions.
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
---
git diff -w still shows no difference.
This patch was sent but December and not applied.
As the trivial maintainer seems not active, it'd be nice if
Andrew Morton picks this up.
V2: Remove fs/xfs/libxfs/xfs_alloc.c as it's updated and remerge the rest
arch/x86/include/asm/atomic64_32.h | 2 +-
drivers/acpi/custom_method.c | 2 +-
drivers/acpi/fan.c | 2 +-
drivers/gpu/drm/amd/display/dc/core/dc.c | 2 +-
drivers/media/i2c/msp3400-kthreads.c | 2 +-
drivers/message/fusion/mptsas.c | 2 +-
drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c | 2 +-
drivers/net/wireless/ath/ath9k/xmit.c | 2 +-
drivers/platform/x86/eeepc-laptop.c | 2 +-
drivers/rtc/rtc-ab-b5ze-s3.c | 2 +-
drivers/scsi/dpt_i2o.c | 2 +-
drivers/scsi/sym53c8xx_2/sym_glue.c | 2 +-
fs/locks.c | 2 +-
fs/ocfs2/stack_user.c | 2 +-
fs/xfs/xfs_export.c | 2 +-
kernel/audit.c | 6 +++---
kernel/trace/trace_printk.c | 4 ++--
lib/raid6/sse2.c | 14 +++++++-------
sound/soc/fsl/fsl_dma.c | 2 +-
19 files changed, 28 insertions(+), 28 deletions(-)
diff --git a/arch/x86/include/asm/atomic64_32.h b/arch/x86/include/asm/atomic64_32.h
index 46e1ef17d92d..92212bf0484f 100644
--- a/arch/x86/include/asm/atomic64_32.h
+++ b/arch/x86/include/asm/atomic64_32.h
@@ -123,7 +123,7 @@ static inline long long arch_atomic64_read(const atomic64_t *v)
long long r;
alternative_atomic64(read, "=&A" (r), "c" (v) : "memory");
return r;
- }
+}
/**
* arch_atomic64_add_return - add and return
diff --git a/drivers/acpi/custom_method.c b/drivers/acpi/custom_method.c
index b33fba70ec51..a07fbe999eb6 100644
--- a/drivers/acpi/custom_method.c
+++ b/drivers/acpi/custom_method.c
@@ -97,7 +97,7 @@ static void __exit acpi_custom_method_exit(void)
{
if (cm_dentry)
debugfs_remove(cm_dentry);
- }
+}
module_init(acpi_custom_method_init);
module_exit(acpi_custom_method_exit);
diff --git a/drivers/acpi/fan.c b/drivers/acpi/fan.c
index 6cf4988206f2..3563103590c6 100644
--- a/drivers/acpi/fan.c
+++ b/drivers/acpi/fan.c
@@ -219,7 +219,7 @@ fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
return fan_set_state_acpi4(device, state);
else
return fan_set_state(device, state);
- }
+}
static const struct thermal_cooling_device_ops fan_cooling_ops = {
.get_max_state = fan_get_max_state,
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
index 8394d69b963f..e934326a95d3 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -588,7 +588,7 @@ static void disable_dangling_plane(struct dc *dc, struct dc_state *context)
******************************************************************************/
struct dc *dc_create(const struct dc_init_data *init_params)
- {
+{
struct dc *dc = kzalloc(sizeof(*dc), GFP_KERNEL);
unsigned int full_pipe_count;
diff --git a/drivers/media/i2c/msp3400-kthreads.c b/drivers/media/i2c/msp3400-kthreads.c
index 4dd01e9f553b..dc6cb8d475b3 100644
--- a/drivers/media/i2c/msp3400-kthreads.c
+++ b/drivers/media/i2c/msp3400-kthreads.c
@@ -885,7 +885,7 @@ static int msp34xxg_modus(struct i2c_client *client)
}
static void msp34xxg_set_source(struct i2c_client *client, u16 reg, int in)
- {
+{
struct msp_state *state = to_state(i2c_get_clientdata(client));
int source, matrix;
diff --git a/drivers/message/fusion/mptsas.c b/drivers/message/fusion/mptsas.c
index 439ee9c5f535..231f3a1e27bf 100644
--- a/drivers/message/fusion/mptsas.c
+++ b/drivers/message/fusion/mptsas.c
@@ -2967,7 +2967,7 @@ mptsas_exp_repmanufacture_info(MPT_ADAPTER *ioc,
mutex_unlock(&ioc->sas_mgmt.mutex);
out:
return ret;
- }
+}
static void
mptsas_parse_device_info(struct sas_identify *identify,
diff --git a/drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c b/drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c
index 3dd973475125..0ea141ece19e 100644
--- a/drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c
+++ b/drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c
@@ -603,7 +603,7 @@ static struct uni_table_desc *nx_get_table_desc(const u8 *unirom, int section)
static int
netxen_nic_validate_header(struct netxen_adapter *adapter)
- {
+{
const u8 *unirom = adapter->fw->data;
struct uni_table_desc *directory = (struct uni_table_desc *) &unirom[0];
u32 fw_file_size = adapter->fw->size;
diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index 396bf05c6bf6..88be55ed5b4d 100644
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -252,7 +252,7 @@ ath_tid_pull(struct ath_atx_tid *tid)
}
return skb;
- }
+}
static bool ath_tid_has_buffered(struct ath_atx_tid *tid)
diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c
index 5a681962899c..4c38904a8a32 100644
--- a/drivers/platform/x86/eeepc-laptop.c
+++ b/drivers/platform/x86/eeepc-laptop.c
@@ -492,7 +492,7 @@ static void eeepc_platform_exit(struct eeepc_laptop *eeepc)
* potentially bad time, such as a timer interrupt.
*/
static void tpd_led_update(struct work_struct *work)
- {
+{
struct eeepc_laptop *eeepc;
eeepc = container_of(work, struct eeepc_laptop, tpd_led_work);
diff --git a/drivers/rtc/rtc-ab-b5ze-s3.c b/drivers/rtc/rtc-ab-b5ze-s3.c
index e55f35fa0b58..8dc451932446 100644
--- a/drivers/rtc/rtc-ab-b5ze-s3.c
+++ b/drivers/rtc/rtc-ab-b5ze-s3.c
@@ -646,7 +646,7 @@ static int abb5zes3_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
ret);
return ret;
- }
+}
/* Enable or disable battery low irq generation */
static inline int _abb5zes3_rtc_battery_low_irq_enable(struct regmap *regmap,
diff --git a/drivers/scsi/dpt_i2o.c b/drivers/scsi/dpt_i2o.c
index 0f30792d74c4..cc5fa99a6530 100644
--- a/drivers/scsi/dpt_i2o.c
+++ b/drivers/scsi/dpt_i2o.c
@@ -3521,7 +3521,7 @@ static int adpt_i2o_systab_send(adpt_hba* pHba)
#endif
return ret;
- }
+}
/*============================================================================
diff --git a/drivers/scsi/sym53c8xx_2/sym_glue.c b/drivers/scsi/sym53c8xx_2/sym_glue.c
index 791a2182de53..7320d5fe4cbc 100644
--- a/drivers/scsi/sym53c8xx_2/sym_glue.c
+++ b/drivers/scsi/sym53c8xx_2/sym_glue.c
@@ -1393,7 +1393,7 @@ static struct Scsi_Host *sym_attach(struct scsi_host_template *tpnt, int unit,
scsi_host_put(shost);
return NULL;
- }
+}
/*
diff --git a/fs/locks.c b/fs/locks.c
index d56a14894fb2..0feaed9f589b 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -559,7 +559,7 @@ static const struct lock_manager_operations lease_manager_ops = {
* Initialize a lease, use the default lock manager operations
*/
static int lease_init(struct file *filp, long type, struct file_lock *fl)
- {
+{
if (assign_type(fl, type) != 0)
return -EINVAL;
diff --git a/fs/ocfs2/stack_user.c b/fs/ocfs2/stack_user.c
index dae9eb7c441e..d2fb97b173da 100644
--- a/fs/ocfs2/stack_user.c
+++ b/fs/ocfs2/stack_user.c
@@ -398,7 +398,7 @@ static int ocfs2_control_do_setnode_msg(struct file *file,
static int ocfs2_control_do_setversion_msg(struct file *file,
struct ocfs2_control_message_setv *msg)
- {
+{
long major, minor;
char *ptr = NULL;
struct ocfs2_control_private *p = file->private_data;
diff --git a/fs/xfs/xfs_export.c b/fs/xfs/xfs_export.c
index 761f3189eff2..eed698aa9f16 100644
--- a/fs/xfs/xfs_export.c
+++ b/fs/xfs/xfs_export.c
@@ -122,7 +122,7 @@ xfs_nfs_get_inode(
struct super_block *sb,
u64 ino,
u32 generation)
- {
+{
xfs_mount_t *mp = XFS_M(sb);
xfs_inode_t *ip;
int error;
diff --git a/kernel/audit.c b/kernel/audit.c
index 8fe6dfb67a94..a97d004375e3 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -486,15 +486,15 @@ static int audit_set_failure(u32 state)
* Drop any references inside the auditd connection tracking struct and free
* the memory.
*/
- static void auditd_conn_free(struct rcu_head *rcu)
- {
+static void auditd_conn_free(struct rcu_head *rcu)
+{
struct auditd_connection *ac;
ac = container_of(rcu, struct auditd_connection, rcu);
put_pid(ac->pid);
put_net(ac->net);
kfree(ac);
- }
+}
/**
* auditd_set - Set/Reset the auditd connection state
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index ad1d6164e946..50f44b7b2b32 100644
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -196,7 +196,7 @@ struct notifier_block module_trace_bprintk_format_nb = {
};
int __trace_bprintk(unsigned long ip, const char *fmt, ...)
- {
+{
int ret;
va_list ap;
@@ -214,7 +214,7 @@ int __trace_bprintk(unsigned long ip, const char *fmt, ...)
EXPORT_SYMBOL_GPL(__trace_bprintk);
int __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap)
- {
+{
if (unlikely(!fmt))
return 0;
diff --git a/lib/raid6/sse2.c b/lib/raid6/sse2.c
index 1d2276b007ee..8191e1d0d2fb 100644
--- a/lib/raid6/sse2.c
+++ b/lib/raid6/sse2.c
@@ -91,7 +91,7 @@ static void raid6_sse21_gen_syndrome(int disks, size_t bytes, void **ptrs)
static void raid6_sse21_xor_syndrome(int disks, int start, int stop,
size_t bytes, void **ptrs)
- {
+{
u8 **dptr = (u8 **)ptrs;
u8 *p, *q;
int d, z, z0;
@@ -200,9 +200,9 @@ static void raid6_sse22_gen_syndrome(int disks, size_t bytes, void **ptrs)
kernel_fpu_end();
}
- static void raid6_sse22_xor_syndrome(int disks, int start, int stop,
+static void raid6_sse22_xor_syndrome(int disks, int start, int stop,
size_t bytes, void **ptrs)
- {
+{
u8 **dptr = (u8 **)ptrs;
u8 *p, *q;
int d, z, z0;
@@ -265,7 +265,7 @@ static void raid6_sse22_gen_syndrome(int disks, size_t bytes, void **ptrs)
asm volatile("sfence" : : : "memory");
kernel_fpu_end();
- }
+}
const struct raid6_calls raid6_sse2x2 = {
raid6_sse22_gen_syndrome,
@@ -366,9 +366,9 @@ static void raid6_sse24_gen_syndrome(int disks, size_t bytes, void **ptrs)
kernel_fpu_end();
}
- static void raid6_sse24_xor_syndrome(int disks, int start, int stop,
+static void raid6_sse24_xor_syndrome(int disks, int start, int stop,
size_t bytes, void **ptrs)
- {
+{
u8 **dptr = (u8 **)ptrs;
u8 *p, *q;
int d, z, z0;
@@ -471,7 +471,7 @@ static void raid6_sse24_gen_syndrome(int disks, size_t bytes, void **ptrs)
}
asm volatile("sfence" : : : "memory");
kernel_fpu_end();
- }
+}
const struct raid6_calls raid6_sse2x4 = {
diff --git a/sound/soc/fsl/fsl_dma.c b/sound/soc/fsl/fsl_dma.c
index fce2010d3c53..78871de35086 100644
--- a/sound/soc/fsl/fsl_dma.c
+++ b/sound/soc/fsl/fsl_dma.c
@@ -886,7 +886,7 @@ static const struct snd_pcm_ops fsl_dma_ops = {
};
static int fsl_soc_dma_probe(struct platform_device *pdev)
- {
+{
struct dma_object *dma;
struct device_node *np = pdev->dev.of_node;
struct device_node *ssi_np;
--
2.15.0
^ permalink raw reply related
* Re: [trivial PATCH V2] treewide: Align function definition open/close braces
From: Rafael J. Wysocki @ 2018-03-21 22:36 UTC (permalink / raw)
To: Joe Perches
Cc: Andrew Morton, Will Deacon, Peter Zijlstra, Boqun Feng,
Rafael J. Wysocki, Len Brown, Zhang Rui, Sathya Prakash,
Chaitra P B, Suganath Prabu Subramani, Manish Chopra, Rahul Verma,
Dept-GELinuxNICDev, QCA ath9k Development, Corentin Chary,
Darren Hart, Andy Shevchenko, Alessandro Zummo, Alexandre Belloni,
Adaptec OEM Raid Solutions, James E.J. Bottomley,
Martin K. Petersen, Matthew Wilcox, Jeff Layton, J. Bruce Fields,
Alexander Viro, Mark Fasheh, Joel Becker, Darrick J. Wong,
linux-xfs, Paul Moore, Eric Paris, Steven Rostedt, Timur Tabi,
Nicolin Chen, Xiubo Li, Fabio Estevam, Jiri Kosina,
Thomas Gleixner, H. Peter Anvin, the arch/x86 maintainers,
Alex Deucher, Christian König, David (ChunMing) Zhou,
David Airlie, Mauro Carvalho Chehab, Kalle Valo, Liam Girdwood,
Mark Brown, Jaroslav Kysela, Takashi Iwai,
Linux Kernel Mailing List, ACPI Devel Maling List, amd-gfx,
dri-devel, linux-media, MPT-FusionLinux.pdl,
open list:TARGET SUBSYSTEM, netdev,
open list:NETWORKING DRIVERS (WIRELESS), acpi4asus-user,
Platform Driver, linux-rtc, linux-fsdevel, ocfs2-devel,
linux-audit,
moderated list:SOUND - SOC LAYER / DYNAMIC AUDIO POWER MANAGEM...,
linuxppc-dev
In-Reply-To: <5ccbbf083e26bddfb4ea4f819ed62347ce266f39.1521669820.git.joe@perches.com>
On Wed, Mar 21, 2018 at 11:09 PM, Joe Perches <joe@perches.com> wrote:
> Some functions definitions have either the initial open brace and/or
> the closing brace outside of column 1.
>
> Move those braces to column 1.
>
> This allows various function analyzers like gnu complexity to work
> properly for these modified functions.
>
> Signed-off-by: Joe Perches <joe@perches.com>
> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> Acked-by: Paul Moore <paul@paul-moore.com>
> Acked-by: Alex Deucher <alexander.deucher@amd.com>
> Acked-by: Dave Chinner <dchinner@redhat.com>
> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
> Acked-by: Takashi Iwai <tiwai@suse.de>
> Acked-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
> ---
>
> git diff -w still shows no difference.
>
> This patch was sent but December and not applied.
>
> As the trivial maintainer seems not active, it'd be nice if
> Andrew Morton picks this up.
>
> V2: Remove fs/xfs/libxfs/xfs_alloc.c as it's updated and remerge the rest
>
> arch/x86/include/asm/atomic64_32.h | 2 +-
> drivers/acpi/custom_method.c | 2 +-
> drivers/acpi/fan.c | 2 +-
For the ACPI changes:
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
^ permalink raw reply
* Re: [PATCH v6 05/12] integrity: Introduce integrity_keyring_from_id()
From: Mimi Zohar @ 2018-03-21 22:46 UTC (permalink / raw)
To: Thiago Jung Bauermann, linux-integrity
Cc: linux-security-module, keyrings, linux-crypto, linuxppc-dev,
linux-kernel, Dmitry Kasatkin, James Morris, Serge E. Hallyn,
David Howells, David Woodhouse, Jessica Yu, Herbert Xu,
David S. Miller, AKASHI, Takahiro
In-Reply-To: <20180316203837.10174-6-bauerman@linux.vnet.ibm.com>
On Fri, 2018-03-16 at 17:38 -0300, Thiago Jung Bauermann wrote:
> IMA will need to obtain the keyring used to verify file signatures so that
> it can verify the module-style signature appended to files.
>
> Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
> ---
> security/integrity/digsig.c | 28 +++++++++++++++++++++-------
> security/integrity/integrity.h | 6 ++++++
> 2 files changed, 27 insertions(+), 7 deletions(-)
>
> diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
> index 6f9e4ce568cd..e641a67b9fc7 100644
> --- a/security/integrity/digsig.c
> +++ b/security/integrity/digsig.c
> @@ -48,11 +48,10 @@ static bool init_keyring __initdata;
> #define restrict_link_to_ima restrict_link_by_builtin_trusted
> #endif
>
> -int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
> - const char *digest, int digestlen)
> +struct key *integrity_keyring_from_id(const unsigned int id)
> {
> - if (id >= INTEGRITY_KEYRING_MAX || siglen < 2)
> - return -EINVAL;
> + if (id >= INTEGRITY_KEYRING_MAX)
> + return ERR_PTR(-EINVAL);
>
> if (!keyring[id]) {
> keyring[id] =
> @@ -61,17 +60,32 @@ int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
> int err = PTR_ERR(keyring[id]);
> pr_err("no %s keyring: %d\n", keyring_name[id], err);
> keyring[id] = NULL;
> - return err;
> + return ERR_PTR(err);
> }
> }
>
> + return keyring[id];
> +}
> +
> +int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
> + const char *digest, int digestlen)
> +{
> + struct key *keyring;
> +
> + if (siglen < 2)
> + return -EINVAL;
> +
> + keyring = integrity_keyring_from_id(id);
> + if (IS_ERR(keyring))
> + return PTR_ERR(keyring);
> +
> switch (sig[1]) {
> case 1:
> /* v1 API expect signature without xattr type */
> - return digsig_verify(keyring[id], sig + 1, siglen - 1,
> + return digsig_verify(keyring, sig + 1, siglen - 1,
> digest, digestlen);
> case 2:
> - return asymmetric_verify(keyring[id], sig, siglen,
> + return asymmetric_verify(keyring, sig, siglen,
> digest, digestlen);
> }
>
> diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
> index 79799a0d9195..2d245f44ca26 100644
> --- a/security/integrity/integrity.h
> +++ b/security/integrity/integrity.h
> @@ -150,6 +150,7 @@ int integrity_kernel_read(struct file *file, loff_t offset,
>
> #ifdef CONFIG_INTEGRITY_SIGNATURE
>
> +struct key *integrity_keyring_from_id(const unsigned int id);
> int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
> const char *digest, int digestlen);
>
> @@ -157,6 +158,11 @@ int __init integrity_init_keyring(const unsigned int id);
> int __init integrity_load_x509(const unsigned int id, const char *path);
> #else
>
> +static inline struct key *integrity_keyring_from_id(const unsigned int id)
> +{
> + return ERR_PTR(-EINVAL);
> +}
> +
> static inline int integrity_digsig_verify(const unsigned int id,
> const char *sig, int siglen,
> const char *digest, int digestlen)
>
^ permalink raw reply
* Re: [trivial PATCH V2] treewide: Align function definition open/close braces
From: Nicolin Chen @ 2018-03-21 22:50 UTC (permalink / raw)
To: Joe Perches
Cc: Andrew Morton, Will Deacon, Peter Zijlstra, Boqun Feng,
Rafael J. Wysocki, Len Brown, Zhang Rui, Sathya Prakash,
Chaitra P B, Suganath Prabu Subramani, Manish Chopra, Rahul Verma,
Dept-GELinuxNICDev, QCA ath9k Development, Corentin Chary,
Darren Hart, Andy Shevchenko, Alessandro Zummo, Alexandre Belloni,
Adaptec OEM Raid Solutions, James E.J. Bottomley,
Martin K. Petersen, Matthew Wilcox, Jeff Layton, J. Bruce Fields,
Alexander Viro, Mark Fasheh, Joel Becker, Darrick J. Wong,
linux-xfs, Paul Moore, Eric Paris, Steven Rostedt, Timur Tabi,
Xiubo Li, Fabio Estevam, Jiri Kosina, Thomas Gleixner,
H. Peter Anvin, x86, Alex Deucher, Christian König,
David (ChunMing) Zhou, David Airlie, Mauro Carvalho Chehab,
Kalle Valo, Liam Girdwood, Mark Brown, Jaroslav Kysela,
Takashi Iwai, linux-kernel, linux-acpi, amd-gfx, dri-devel,
linux-media, MPT-FusionLinux.pdl, linux-scsi, netdev,
linux-wireless, acpi4asus-user, platform-driver-x86, linux-rtc,
linux-fsdevel, ocfs2-devel, linux-audit, alsa-devel, linuxppc-dev
In-Reply-To: <5ccbbf083e26bddfb4ea4f819ed62347ce266f39.1521669820.git.joe@perches.com>
On Wed, Mar 21, 2018 at 03:09:32PM -0700, Joe Perches wrote:
> Some functions definitions have either the initial open brace and/or
> the closing brace outside of column 1.
>
> Move those braces to column 1.
>
> This allows various function analyzers like gnu complexity to work
> properly for these modified functions.
>
> Signed-off-by: Joe Perches <joe@perches.com>
> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> Acked-by: Paul Moore <paul@paul-moore.com>
> Acked-by: Alex Deucher <alexander.deucher@amd.com>
> Acked-by: Dave Chinner <dchinner@redhat.com>
> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
> Acked-by: Takashi Iwai <tiwai@suse.de>
> Acked-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
> ---
>
> git diff -w still shows no difference.
>
> This patch was sent but December and not applied.
>
> As the trivial maintainer seems not active, it'd be nice if
> Andrew Morton picks this up.
>
> V2: Remove fs/xfs/libxfs/xfs_alloc.c as it's updated and remerge the rest
>
> arch/x86/include/asm/atomic64_32.h | 2 +-
> drivers/acpi/custom_method.c | 2 +-
> drivers/acpi/fan.c | 2 +-
> drivers/gpu/drm/amd/display/dc/core/dc.c | 2 +-
> drivers/media/i2c/msp3400-kthreads.c | 2 +-
> drivers/message/fusion/mptsas.c | 2 +-
> drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c | 2 +-
> drivers/net/wireless/ath/ath9k/xmit.c | 2 +-
> drivers/platform/x86/eeepc-laptop.c | 2 +-
> drivers/rtc/rtc-ab-b5ze-s3.c | 2 +-
> drivers/scsi/dpt_i2o.c | 2 +-
> drivers/scsi/sym53c8xx_2/sym_glue.c | 2 +-
> fs/locks.c | 2 +-
> fs/ocfs2/stack_user.c | 2 +-
> fs/xfs/xfs_export.c | 2 +-
> kernel/audit.c | 6 +++---
> kernel/trace/trace_printk.c | 4 ++--
> lib/raid6/sse2.c | 14 +++++++-------
For fsl_dma.c:
> sound/soc/fsl/fsl_dma.c | 2 +-
Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>
Thanks
> 19 files changed, 28 insertions(+), 28 deletions(-)
>
> diff --git a/arch/x86/include/asm/atomic64_32.h b/arch/x86/include/asm/atomic64_32.h
> index 46e1ef17d92d..92212bf0484f 100644
> --- a/arch/x86/include/asm/atomic64_32.h
> +++ b/arch/x86/include/asm/atomic64_32.h
> @@ -123,7 +123,7 @@ static inline long long arch_atomic64_read(const atomic64_t *v)
> long long r;
> alternative_atomic64(read, "=&A" (r), "c" (v) : "memory");
> return r;
> - }
> +}
>
> /**
> * arch_atomic64_add_return - add and return
> diff --git a/drivers/acpi/custom_method.c b/drivers/acpi/custom_method.c
> index b33fba70ec51..a07fbe999eb6 100644
> --- a/drivers/acpi/custom_method.c
> +++ b/drivers/acpi/custom_method.c
> @@ -97,7 +97,7 @@ static void __exit acpi_custom_method_exit(void)
> {
> if (cm_dentry)
> debugfs_remove(cm_dentry);
> - }
> +}
>
> module_init(acpi_custom_method_init);
> module_exit(acpi_custom_method_exit);
> diff --git a/drivers/acpi/fan.c b/drivers/acpi/fan.c
> index 6cf4988206f2..3563103590c6 100644
> --- a/drivers/acpi/fan.c
> +++ b/drivers/acpi/fan.c
> @@ -219,7 +219,7 @@ fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
> return fan_set_state_acpi4(device, state);
> else
> return fan_set_state(device, state);
> - }
> +}
>
> static const struct thermal_cooling_device_ops fan_cooling_ops = {
> .get_max_state = fan_get_max_state,
> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
> index 8394d69b963f..e934326a95d3 100644
> --- a/drivers/gpu/drm/amd/display/dc/core/dc.c
> +++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
> @@ -588,7 +588,7 @@ static void disable_dangling_plane(struct dc *dc, struct dc_state *context)
> ******************************************************************************/
>
> struct dc *dc_create(const struct dc_init_data *init_params)
> - {
> +{
> struct dc *dc = kzalloc(sizeof(*dc), GFP_KERNEL);
> unsigned int full_pipe_count;
>
> diff --git a/drivers/media/i2c/msp3400-kthreads.c b/drivers/media/i2c/msp3400-kthreads.c
> index 4dd01e9f553b..dc6cb8d475b3 100644
> --- a/drivers/media/i2c/msp3400-kthreads.c
> +++ b/drivers/media/i2c/msp3400-kthreads.c
> @@ -885,7 +885,7 @@ static int msp34xxg_modus(struct i2c_client *client)
> }
>
> static void msp34xxg_set_source(struct i2c_client *client, u16 reg, int in)
> - {
> +{
> struct msp_state *state = to_state(i2c_get_clientdata(client));
> int source, matrix;
>
> diff --git a/drivers/message/fusion/mptsas.c b/drivers/message/fusion/mptsas.c
> index 439ee9c5f535..231f3a1e27bf 100644
> --- a/drivers/message/fusion/mptsas.c
> +++ b/drivers/message/fusion/mptsas.c
> @@ -2967,7 +2967,7 @@ mptsas_exp_repmanufacture_info(MPT_ADAPTER *ioc,
> mutex_unlock(&ioc->sas_mgmt.mutex);
> out:
> return ret;
> - }
> +}
>
> static void
> mptsas_parse_device_info(struct sas_identify *identify,
> diff --git a/drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c b/drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c
> index 3dd973475125..0ea141ece19e 100644
> --- a/drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c
> +++ b/drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c
> @@ -603,7 +603,7 @@ static struct uni_table_desc *nx_get_table_desc(const u8 *unirom, int section)
>
> static int
> netxen_nic_validate_header(struct netxen_adapter *adapter)
> - {
> +{
> const u8 *unirom = adapter->fw->data;
> struct uni_table_desc *directory = (struct uni_table_desc *) &unirom[0];
> u32 fw_file_size = adapter->fw->size;
> diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
> index 396bf05c6bf6..88be55ed5b4d 100644
> --- a/drivers/net/wireless/ath/ath9k/xmit.c
> +++ b/drivers/net/wireless/ath/ath9k/xmit.c
> @@ -252,7 +252,7 @@ ath_tid_pull(struct ath_atx_tid *tid)
> }
>
> return skb;
> - }
> +}
>
>
> static bool ath_tid_has_buffered(struct ath_atx_tid *tid)
> diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c
> index 5a681962899c..4c38904a8a32 100644
> --- a/drivers/platform/x86/eeepc-laptop.c
> +++ b/drivers/platform/x86/eeepc-laptop.c
> @@ -492,7 +492,7 @@ static void eeepc_platform_exit(struct eeepc_laptop *eeepc)
> * potentially bad time, such as a timer interrupt.
> */
> static void tpd_led_update(struct work_struct *work)
> - {
> +{
> struct eeepc_laptop *eeepc;
>
> eeepc = container_of(work, struct eeepc_laptop, tpd_led_work);
> diff --git a/drivers/rtc/rtc-ab-b5ze-s3.c b/drivers/rtc/rtc-ab-b5ze-s3.c
> index e55f35fa0b58..8dc451932446 100644
> --- a/drivers/rtc/rtc-ab-b5ze-s3.c
> +++ b/drivers/rtc/rtc-ab-b5ze-s3.c
> @@ -646,7 +646,7 @@ static int abb5zes3_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
> ret);
>
> return ret;
> - }
> +}
>
> /* Enable or disable battery low irq generation */
> static inline int _abb5zes3_rtc_battery_low_irq_enable(struct regmap *regmap,
> diff --git a/drivers/scsi/dpt_i2o.c b/drivers/scsi/dpt_i2o.c
> index 0f30792d74c4..cc5fa99a6530 100644
> --- a/drivers/scsi/dpt_i2o.c
> +++ b/drivers/scsi/dpt_i2o.c
> @@ -3521,7 +3521,7 @@ static int adpt_i2o_systab_send(adpt_hba* pHba)
> #endif
>
> return ret;
> - }
> +}
>
>
> /*============================================================================
> diff --git a/drivers/scsi/sym53c8xx_2/sym_glue.c b/drivers/scsi/sym53c8xx_2/sym_glue.c
> index 791a2182de53..7320d5fe4cbc 100644
> --- a/drivers/scsi/sym53c8xx_2/sym_glue.c
> +++ b/drivers/scsi/sym53c8xx_2/sym_glue.c
> @@ -1393,7 +1393,7 @@ static struct Scsi_Host *sym_attach(struct scsi_host_template *tpnt, int unit,
> scsi_host_put(shost);
>
> return NULL;
> - }
> +}
>
>
> /*
> diff --git a/fs/locks.c b/fs/locks.c
> index d56a14894fb2..0feaed9f589b 100644
> --- a/fs/locks.c
> +++ b/fs/locks.c
> @@ -559,7 +559,7 @@ static const struct lock_manager_operations lease_manager_ops = {
> * Initialize a lease, use the default lock manager operations
> */
> static int lease_init(struct file *filp, long type, struct file_lock *fl)
> - {
> +{
> if (assign_type(fl, type) != 0)
> return -EINVAL;
>
> diff --git a/fs/ocfs2/stack_user.c b/fs/ocfs2/stack_user.c
> index dae9eb7c441e..d2fb97b173da 100644
> --- a/fs/ocfs2/stack_user.c
> +++ b/fs/ocfs2/stack_user.c
> @@ -398,7 +398,7 @@ static int ocfs2_control_do_setnode_msg(struct file *file,
>
> static int ocfs2_control_do_setversion_msg(struct file *file,
> struct ocfs2_control_message_setv *msg)
> - {
> +{
> long major, minor;
> char *ptr = NULL;
> struct ocfs2_control_private *p = file->private_data;
> diff --git a/fs/xfs/xfs_export.c b/fs/xfs/xfs_export.c
> index 761f3189eff2..eed698aa9f16 100644
> --- a/fs/xfs/xfs_export.c
> +++ b/fs/xfs/xfs_export.c
> @@ -122,7 +122,7 @@ xfs_nfs_get_inode(
> struct super_block *sb,
> u64 ino,
> u32 generation)
> - {
> +{
> xfs_mount_t *mp = XFS_M(sb);
> xfs_inode_t *ip;
> int error;
> diff --git a/kernel/audit.c b/kernel/audit.c
> index 8fe6dfb67a94..a97d004375e3 100644
> --- a/kernel/audit.c
> +++ b/kernel/audit.c
> @@ -486,15 +486,15 @@ static int audit_set_failure(u32 state)
> * Drop any references inside the auditd connection tracking struct and free
> * the memory.
> */
> - static void auditd_conn_free(struct rcu_head *rcu)
> - {
> +static void auditd_conn_free(struct rcu_head *rcu)
> +{
> struct auditd_connection *ac;
>
> ac = container_of(rcu, struct auditd_connection, rcu);
> put_pid(ac->pid);
> put_net(ac->net);
> kfree(ac);
> - }
> +}
>
> /**
> * auditd_set - Set/Reset the auditd connection state
> diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
> index ad1d6164e946..50f44b7b2b32 100644
> --- a/kernel/trace/trace_printk.c
> +++ b/kernel/trace/trace_printk.c
> @@ -196,7 +196,7 @@ struct notifier_block module_trace_bprintk_format_nb = {
> };
>
> int __trace_bprintk(unsigned long ip, const char *fmt, ...)
> - {
> +{
> int ret;
> va_list ap;
>
> @@ -214,7 +214,7 @@ int __trace_bprintk(unsigned long ip, const char *fmt, ...)
> EXPORT_SYMBOL_GPL(__trace_bprintk);
>
> int __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap)
> - {
> +{
> if (unlikely(!fmt))
> return 0;
>
> diff --git a/lib/raid6/sse2.c b/lib/raid6/sse2.c
> index 1d2276b007ee..8191e1d0d2fb 100644
> --- a/lib/raid6/sse2.c
> +++ b/lib/raid6/sse2.c
> @@ -91,7 +91,7 @@ static void raid6_sse21_gen_syndrome(int disks, size_t bytes, void **ptrs)
>
> static void raid6_sse21_xor_syndrome(int disks, int start, int stop,
> size_t bytes, void **ptrs)
> - {
> +{
> u8 **dptr = (u8 **)ptrs;
> u8 *p, *q;
> int d, z, z0;
> @@ -200,9 +200,9 @@ static void raid6_sse22_gen_syndrome(int disks, size_t bytes, void **ptrs)
> kernel_fpu_end();
> }
>
> - static void raid6_sse22_xor_syndrome(int disks, int start, int stop,
> +static void raid6_sse22_xor_syndrome(int disks, int start, int stop,
> size_t bytes, void **ptrs)
> - {
> +{
> u8 **dptr = (u8 **)ptrs;
> u8 *p, *q;
> int d, z, z0;
> @@ -265,7 +265,7 @@ static void raid6_sse22_gen_syndrome(int disks, size_t bytes, void **ptrs)
>
> asm volatile("sfence" : : : "memory");
> kernel_fpu_end();
> - }
> +}
>
> const struct raid6_calls raid6_sse2x2 = {
> raid6_sse22_gen_syndrome,
> @@ -366,9 +366,9 @@ static void raid6_sse24_gen_syndrome(int disks, size_t bytes, void **ptrs)
> kernel_fpu_end();
> }
>
> - static void raid6_sse24_xor_syndrome(int disks, int start, int stop,
> +static void raid6_sse24_xor_syndrome(int disks, int start, int stop,
> size_t bytes, void **ptrs)
> - {
> +{
> u8 **dptr = (u8 **)ptrs;
> u8 *p, *q;
> int d, z, z0;
> @@ -471,7 +471,7 @@ static void raid6_sse24_gen_syndrome(int disks, size_t bytes, void **ptrs)
> }
> asm volatile("sfence" : : : "memory");
> kernel_fpu_end();
> - }
> +}
>
>
> const struct raid6_calls raid6_sse2x4 = {
> diff --git a/sound/soc/fsl/fsl_dma.c b/sound/soc/fsl/fsl_dma.c
> index fce2010d3c53..78871de35086 100644
> --- a/sound/soc/fsl/fsl_dma.c
> +++ b/sound/soc/fsl/fsl_dma.c
> @@ -886,7 +886,7 @@ static const struct snd_pcm_ops fsl_dma_ops = {
> };
>
> static int fsl_soc_dma_probe(struct platform_device *pdev)
> - {
> +{
> struct dma_object *dma;
> struct device_node *np = pdev->dev.of_node;
> struct device_node *ssi_np;
> --
> 2.15.0
>
^ permalink raw reply
* Re: [trivial PATCH V2] treewide: Align function definition open/close braces
From: Martin K. Petersen @ 2018-03-21 22:53 UTC (permalink / raw)
To: Joe Perches
Cc: Andrew Morton, Will Deacon, Peter Zijlstra, Boqun Feng,
Rafael J. Wysocki, Len Brown, Zhang Rui, Sathya Prakash,
Chaitra P B, Suganath Prabu Subramani, Manish Chopra, Rahul Verma,
Dept-GELinuxNICDev, QCA ath9k Development, Corentin Chary,
Darren Hart, Andy Shevchenko, Alessandro Zummo, Alexandre Belloni,
Adaptec OEM Raid Solutions, James E.J. Bottomley,
Martin K. Petersen, Matthew Wilcox, Jeff Layton, J. Bruce Fields,
Alexander Viro, Mark Fasheh, Joel Becker, Darrick J. Wong,
linux-xfs, Paul Moore, Eric Paris, Steven Rostedt, Timur Tabi,
Nicolin Chen, Xiubo Li, Fabio Estevam, Jiri Kosina,
Thomas Gleixner, H. Peter Anvin, x86, Alex Deucher,
Christian König, David (ChunMing) Zhou, David Airlie,
Mauro Carvalho Chehab, Kalle Valo, Liam Girdwood, Mark Brown,
Jaroslav Kysela, Takashi Iwai, linux-kernel, linux-acpi, amd-gfx,
dri-devel, linux-media, MPT-FusionLinux.pdl, linux-scsi, netdev,
linux-wireless, acpi4asus-user, platform-driver-x86, linux-rtc,
linux-fsdevel, ocfs2-devel, linux-audit, alsa-devel, linuxppc-dev
In-Reply-To: <5ccbbf083e26bddfb4ea4f819ed62347ce266f39.1521669820.git.joe@perches.com>
Joe,
> Some functions definitions have either the initial open brace and/or
> the closing brace outside of column 1.
>
> Move those braces to column 1.
drivers/scsi and drivers/message/fusion parts look fine.
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
--
Martin K. Petersen Oracle Linux Engineering
^ permalink raw reply
* Re: [PATCH v6 06/12] integrity: Introduce asymmetric_sig_has_known_key()
From: Mimi Zohar @ 2018-03-21 23:17 UTC (permalink / raw)
To: Thiago Jung Bauermann, linux-integrity
Cc: linux-security-module, keyrings, linux-crypto, linuxppc-dev,
linux-kernel, Dmitry Kasatkin, James Morris, Serge E. Hallyn,
David Howells, David Woodhouse, Jessica Yu, Herbert Xu,
David S. Miller, AKASHI, Takahiro
In-Reply-To: <20180316203837.10174-7-bauerman@linux.vnet.ibm.com>
On Fri, 2018-03-16 at 17:38 -0300, Thiago Jung Bauermann wrote:
> IMA will only look for a modsig if the xattr sig references a key which is
> not in the expected kernel keyring. To that end, introduce
> asymmetric_sig_has_known_key().
>
> The logic of extracting the key used in the xattr sig is factored out from
> asymmetric_verify() so that it can be used by the new function.
>
> Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
> ---
> security/integrity/digsig_asymmetric.c | 44 +++++++++++++++++++++++++---------
> security/integrity/integrity.h | 8 +++++++
> 2 files changed, 41 insertions(+), 11 deletions(-)
>
> diff --git a/security/integrity/digsig_asymmetric.c b/security/integrity/digsig_asymmetric.c
> index ab6a029062a1..241647970c19 100644
> --- a/security/integrity/digsig_asymmetric.c
> +++ b/security/integrity/digsig_asymmetric.c
> @@ -79,26 +79,48 @@ static struct key *request_asymmetric_key(struct key *keyring, uint32_t keyid)
> return key;
> }
>
> -int asymmetric_verify(struct key *keyring, const char *sig,
> - int siglen, const char *data, int datalen)
> +static struct key *asymmetric_key_from_sig(struct key *keyring, const char *sig,
> + int siglen)
> {
> - struct public_key_signature pks;
> - struct signature_v2_hdr *hdr = (struct signature_v2_hdr *)sig;
> - struct key *key;
> - int ret = -ENOMEM;
> + const struct signature_v2_hdr *hdr = (struct signature_v2_hdr *) sig;
>
> if (siglen <= sizeof(*hdr))
> - return -EBADMSG;
> + return ERR_PTR(-EBADMSG);
>
> siglen -= sizeof(*hdr);
>
> if (siglen != be16_to_cpu(hdr->sig_size))
> - return -EBADMSG;
> + return ERR_PTR(-EBADMSG);
>
> if (hdr->hash_algo >= HASH_ALGO__LAST)
> - return -ENOPKG;
> + return ERR_PTR(-ENOPKG);
> +
> + return request_asymmetric_key(keyring, be32_to_cpu(hdr->keyid));
> +}
> +
> +bool asymmetric_sig_has_known_key(struct key *keyring, const char *sig,
> + int siglen)
> +{
> + struct key *key;
> +
> + key = asymmetric_key_from_sig(keyring, sig, siglen);
> + if (IS_ERR_OR_NULL(key))
> + return false;
> +
> + key_put(key);
> +
> + return true;
> +}
> +
> +int asymmetric_verify(struct key *keyring, const char *sig,
> + int siglen, const char *data, int datalen)
> +{
> + struct public_key_signature pks;
> + struct signature_v2_hdr *hdr = (struct signature_v2_hdr *)sig;
> + struct key *key;
> + int ret = -ENOMEM;
>
> - key = request_asymmetric_key(keyring, be32_to_cpu(hdr->keyid));
> + key = asymmetric_key_from_sig(keyring, sig, siglen);
> if (IS_ERR(key))
> return PTR_ERR(key);
>
> @@ -109,7 +131,7 @@ int asymmetric_verify(struct key *keyring, const char *sig,
> pks.digest = (u8 *)data;
> pks.digest_size = datalen;
> pks.s = hdr->sig;
> - pks.s_size = siglen;
> + pks.s_size = siglen - sizeof(*hdr);
> ret = verify_signature(key, &pks);
> key_put(key);
> pr_debug("%s() = %d\n", __func__, ret);
> diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
> index 2d245f44ca26..4c381b992e11 100644
> --- a/security/integrity/integrity.h
> +++ b/security/integrity/integrity.h
> @@ -179,12 +179,20 @@ static inline int integrity_init_keyring(const unsigned int id)
> #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
> int asymmetric_verify(struct key *keyring, const char *sig,
> int siglen, const char *data, int datalen);
> +bool asymmetric_sig_has_known_key(struct key *keyring, const char *sig,
> + int siglen);
> #else
> static inline int asymmetric_verify(struct key *keyring, const char *sig,
> int siglen, const char *data, int datalen)
> {
> return -EOPNOTSUPP;
> }
> +
> +static inline bool asymmetric_sig_has_known_key(struct key *keyring,
> + const char *sig, int siglen)
> +{
> + return false;
> +}
> #endif
>
> #ifdef CONFIG_IMA_LOAD_X509
>
^ permalink raw reply
* Re: [PATCH v6 07/12] integrity: Select CONFIG_KEYS instead of depending on it
From: Mimi Zohar @ 2018-03-21 23:18 UTC (permalink / raw)
To: Thiago Jung Bauermann, linux-integrity
Cc: linux-security-module, keyrings, linux-crypto, linuxppc-dev,
linux-kernel, Dmitry Kasatkin, James Morris, Serge E. Hallyn,
David Howells, David Woodhouse, Jessica Yu, Herbert Xu,
David S. Miller, AKASHI, Takahiro
In-Reply-To: <20180316203837.10174-8-bauerman@linux.vnet.ibm.com>
On Fri, 2018-03-16 at 17:38 -0300, Thiago Jung Bauermann wrote:
> This avoids a dependency cycle in CONFIG_IMA_APPRAISE_MODSIG (introduced by
> a later patch in this series): it will select CONFIG_MODULE_SIG_FORMAT
> which in turn selects CONFIG_KEYS. Kconfig then complains that
> CONFIG_INTEGRITY_SIGNATURE depends on CONFIG_KEYS.
>
> Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
> ---
> security/integrity/Kconfig | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/security/integrity/Kconfig b/security/integrity/Kconfig
> index da9565891738..0d642e0317c7 100644
> --- a/security/integrity/Kconfig
> +++ b/security/integrity/Kconfig
> @@ -17,8 +17,8 @@ if INTEGRITY
>
> config INTEGRITY_SIGNATURE
> bool "Digital signature verification using multiple keyrings"
> - depends on KEYS
> default n
> + select KEYS
> select SIGNATURE
> help
> This option enables digital signature verification support
>
^ permalink raw reply
* Re: [RFC PATCH 4/6] mm: provide generic compat_sys_readahead() implementation
From: Al Viro @ 2018-03-22 0:15 UTC (permalink / raw)
To: Ingo Molnar
Cc: Linus Torvalds, Dominik Brodowski, Linux Kernel Mailing List,
Arnd Bergmann, linux-arch, Ralf Baechle, James Hogan, linux-mips,
Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, ppc-dev,
Martin Schwidefsky, Heiko Carstens, linux-s390, David S . Miller,
sparclinux, Ingo Molnar, Jiri Slaby, the arch/x86 maintainers
In-Reply-To: <20180319232342.GX30522@ZenIV.linux.org.uk>
On Mon, Mar 19, 2018 at 11:23:42PM +0000, Al Viro wrote:
> Benefits:
> * all SyS... wrappers (i.e. the thing that really ought to
> go into syscall tables) have the same type.
> * we could have SYSCALL_DEFINE produce a trivial compat
> wrapper, have explicit COMPAT_SYSCALL_DEFINE discard that thing
> and populate the compat syscall table *entirely* with compat_SyS_...,
> letting the linker sort it out. That way we don't need to keep
> track of what can use native and what needs compat in each compat
> table on biarch.
> * s390 compat wrappers would disappear with that approach.
> * we could even stop generating sys_... aliases - if
> syscall table is generated by slapping SyS_... or compat_SyS_...
> on the name given there, we don't need to _have_ those sys_...
> things at all. All SyS_... would have the same type, so the pile
> in syscalls.h would not be needed - we could generate the externs
> at the same time we generate the syscall table.
>
> And yes, it's a high-squick approach. I know and I'm not saying
> it's a good idea. OTOH, to quote the motto of philosophers and
> shell game operators, "there's something in it"...
FWIW, I have something that is almost reasonable on preprocessor side;
however, that has uncovered the following fun:
void f(unsigned long long);
void g(unsigned a, unsigned b)
{
f((((unsigned long long)b)<<32)|a);
}
which does compile to "jump to f" on i386, ends up with the following
joy on arm:
mov r3, r1
mov r2, #0
push {r4, lr}
orr r2, r2, r0
mov r0, r2
mov r1, r3
bl f
pop {r4, lr}
bx lr
with gcc6; gcc7 is saner - there we have just
mov r2, #0
orr r0, r2, r0
b f
The former is
r3 = r1
r2 = 0
r2 |= r0
r0 = r2
r1 = r3
The latter -
r2 = 0
r0 |= r2
which is better, but still bloody odd
And I'm afraid to check what e.g. 4.4 will do with that testcase...
^ permalink raw reply
* Re: [PATCH v9 00/24] Speculative page faults
From: Ganesh Mahendran @ 2018-03-22 1:21 UTC (permalink / raw)
To: Laurent Dufour
Cc: paulmck, Peter Zijlstra, Andrew Morton, kirill, ak, Michal Hocko,
dave, jack, Matthew Wilcox, benh, mpe, paulus, Thomas Gleixner,
Ingo Molnar, hpa, Will Deacon, Sergey Senozhatsky,
Andrea Arcangeli, Alexei Starovoitov, kemi.wang,
Sergey Senozhatsky, Daniel Jordan, linux-kernel, Linux-MM, haren,
khandual, npiggin, Balbir Singh, Tim Chen, linuxppc-dev, x86
In-Reply-To: <1520963994-28477-1-git-send-email-ldufour@linux.vnet.ibm.com>
Hi, Laurent
2018-03-14 1:59 GMT+08:00 Laurent Dufour <ldufour@linux.vnet.ibm.com>:
> This is a port on kernel 4.16 of the work done by Peter Zijlstra to
> handle page fault without holding the mm semaphore [1].
>
> The idea is to try to handle user space page faults without holding the
> mmap_sem. This should allow better concurrency for massively threaded
> process since the page fault handler will not wait for other threads memory
> layout change to be done, assuming that this change is done in another part
> of the process's memory space. This type page fault is named speculative
> page fault. If the speculative page fault fails because of a concurrency is
> detected or because underlying PMD or PTE tables are not yet allocating, it
> is failing its processing and a classic page fault is then tried.
>
> The speculative page fault (SPF) has to look for the VMA matching the fault
> address without holding the mmap_sem, this is done by introducing a rwlock
> which protects the access to the mm_rb tree. Previously this was done using
> SRCU but it was introducing a lot of scheduling to process the VMA's
> freeing
> operation which was hitting the performance by 20% as reported by Kemi Wang
> [2].Using a rwlock to protect access to the mm_rb tree is limiting the
> locking contention to these operations which are expected to be in a O(log
> n)
> order. In addition to ensure that the VMA is not freed in our back a
> reference count is added and 2 services (get_vma() and put_vma()) are
> introduced to handle the reference count. When a VMA is fetch from the RB
> tree using get_vma() is must be later freeed using put_vma(). Furthermore,
> to allow the VMA to be used again by the classic page fault handler a
> service is introduced can_reuse_spf_vma(). This service is expected to be
> called with the mmap_sem hold. It checked that the VMA is still matching
> the specified address and is releasing its reference count as the mmap_sem
> is hold it is ensure that it will not be freed in our back. In general, the
> VMA's reference count could be decremented when holding the mmap_sem but it
> should not be increased as holding the mmap_sem is ensuring that the VMA is
> stable. I can't see anymore the overhead I got while will-it-scale
> benchmark anymore.
>
> The VMA's attributes checked during the speculative page fault processing
> have to be protected against parallel changes. This is done by using a per
> VMA sequence lock. This sequence lock allows the speculative page fault
> handler to fast check for parallel changes in progress and to abort the
> speculative page fault in that case.
>
> Once the VMA is found, the speculative page fault handler would check for
> the VMA's attributes to verify that the page fault has to be handled
> correctly or not. Thus the VMA is protected through a sequence lock which
> allows fast detection of concurrent VMA changes. If such a change is
> detected, the speculative page fault is aborted and a *classic* page fault
> is tried. VMA sequence lockings are added when VMA attributes which are
> checked during the page fault are modified.
>
> When the PTE is fetched, the VMA is checked to see if it has been changed,
> so once the page table is locked, the VMA is valid, so any other changes
> leading to touching this PTE will need to lock the page table, so no
> parallel change is possible at this time.
>
> The locking of the PTE is done with interrupts disabled, this allows to
> check for the PMD to ensure that there is not an ongoing collapsing
> operation. Since khugepaged is firstly set the PMD to pmd_none and then is
> waiting for the other CPU to have catch the IPI interrupt, if the pmd is
> valid at the time the PTE is locked, we have the guarantee that the
> collapsing opertion will have to wait on the PTE lock to move foward. This
> allows the SPF handler to map the PTE safely. If the PMD value is different
> than the one recorded at the beginning of the SPF operation, the classic
> page fault handler will be called to handle the operation while holding the
> mmap_sem. As the PTE lock is done with the interrupts disabled, the lock is
> done using spin_trylock() to avoid dead lock when handling a page fault
> while a TLB invalidate is requested by an other CPU holding the PTE.
>
> Support for THP is not done because when checking for the PMD, we can be
> confused by an in progress collapsing operation done by khugepaged. The
> issue is that pmd_none() could be true either if the PMD is not already
> populated or if the underlying PTE are in the way to be collapsed. So we
> cannot safely allocate a PMD if pmd_none() is true.
>
> This series a new software performance event named 'speculative-faults' or
> 'spf'. It counts the number of successful page fault event handled in a
> speculative way. When recording 'faults,spf' events, the faults one is
> counting the total number of page fault events while 'spf' is only counting
> the part of the faults processed in a speculative way.
>
> There are some trace events introduced by this series. They allow to
> identify why the page faults where not processed in a speculative way. This
> doesn't take in account the faults generated by a monothreaded process
> which directly processed while holding the mmap_sem. This trace events are
> grouped in a system named 'pagefault', they are:
> - pagefault:spf_pte_lock : if the pte was already locked by another thread
> - pagefault:spf_vma_changed : if the VMA has been changed in our back
> - pagefault:spf_vma_noanon : the vma->anon_vma field was not yet set.
> - pagefault:spf_vma_notsup : the VMA's type is not supported
> - pagefault:spf_vma_access : the VMA's access right are not respected
> - pagefault:spf_pmd_changed : the upper PMD pointer has changed in our
> back.
>
> To record all the related events, the easier is to run perf with the
> following arguments :
> $ perf stat -e 'faults,spf,pagefault:*' <command>
>
> This series builds on top of v4.16-rc2-mmotm-2018-02-21-14-48 and is
> functional on x86 and PowerPC.
>
> ---------------------
> Real Workload results
>
> As mentioned in previous email, we did non official runs using a "popular
> in memory multithreaded database product" on 176 cores SMT8 Power system
> which showed a 30% improvements in the number of transaction processed per
> second. This run has been done on the v6 series, but changes introduced in
> this new verion should not impact the performance boost seen.
>
> Here are the perf data captured during 2 of these runs on top of the v8
> series:
> vanilla spf
> faults 89.418 101.364
> spf n/a 97.989
>
> With the SPF kernel, most of the page fault were processed in a speculative
> way.
>
> ------------------
> Benchmarks results
>
> Base kernel is v4.16-rc4-mmotm-2018-03-09-16-34
> SPF is BASE + this series
>
> Kernbench:
> ----------
> Here are the results on a 16 CPUs X86 guest using kernbench on a 4.13-rc4
> kernel (kernel is build 5 times):
>
> Average Half load -j 8
> Run (std deviation)
> BASE SPF
> Elapsed Time 151.36 (1.40139) 151.748 (1.09716) 0.26%
> User Time 1023.19 (3.58972) 1027.35 (2.30396) 0.41%
> System Time 125.026 (1.8547) 124.504 (0.980015) -0.42%
> Percent CPU 758.2 (5.54076) 758.6 (3.97492) 0.05%
> Context Switches 54924 (453.634) 54851 (382.293) -0.13%
> Sleeps 105589 (704.581) 105282 (435.502) -0.29%
>
> Average Optimal load -j 16
> Run (std deviation)
> BASE SPF
> Elapsed Time 74.804 (1.25139) 74.368 (0.406288) -0.58%
> User Time 962.033 (64.5125) 963.93 (66.8797) 0.20%
> System Time 110.771 (15.0817) 110.387 (14.8989) -0.35%
> Percent CPU 1045.7 (303.387) 1049.1 (306.255) 0.33%
> Context Switches 76201.8 (22433.1) 76170.4 (22482.9) -0.04%
> Sleeps 110289 (5024.05) 110220 (5248.58) -0.06%
>
> During a run on the SPF, perf events were captured:
> Performance counter stats for '../kernbench -M':
> 510334017 faults
> 200 spf
> 0 pagefault:spf_pte_lock
> 0 pagefault:spf_vma_changed
> 0 pagefault:spf_vma_noanon
> 2174 pagefault:spf_vma_notsup
> 0 pagefault:spf_vma_access
> 0 pagefault:spf_pmd_changed
>
> Very few speculative page fault were recorded as most of the processes
> involved are monothreaded (sounds that on this architecture some threads
> were created during the kernel build processing).
>
> Here are the kerbench results on a 80 CPUs Power8 system:
>
> Average Half load -j 40
> Run (std deviation)
> BASE SPF
> Elapsed Time 116.958 (0.73401) 117.43 (0.927497) 0.40%
> User Time 4472.35 (7.85792) 4480.16 (19.4909) 0.17%
> System Time 136.248 (0.587639) 136.922 (1.09058) 0.49%
> Percent CPU 3939.8 (20.6567) 3931.2 (17.2829) -0.22%
> Context Switches 92445.8 (236.672) 92720.8 (270.118) 0.30%
> Sleeps 318475 (1412.6) 317996 (1819.07) -0.15%
>
> Average Optimal load -j 80
> Run (std deviation)
> BASE SPF
> Elapsed Time 106.976 (0.406731) 107.72 (0.329014) 0.70%
> User Time 5863.47 (1466.45) 5865.38 (1460.27) 0.03%
> System Time 159.995 (25.0393) 160.329 (24.6921) 0.21%
> Percent CPU 5446.2 (1588.23) 5416 (1565.34) -0.55%
> Context Switches 223018 (137637) 224867 (139305) 0.83%
> Sleeps 330846 (13127.3) 332348 (15556.9) 0.45%
>
> During a run on the SPF, perf events were captured:
> Performance counter stats for '../kernbench -M':
> 116612488 faults
> 0 spf
> 0 pagefault:spf_pte_lock
> 0 pagefault:spf_vma_changed
> 0 pagefault:spf_vma_noanon
> 473 pagefault:spf_vma_notsup
> 0 pagefault:spf_vma_access
> 0 pagefault:spf_pmd_changed
>
> Most of the processes involved are monothreaded so SPF is not activated but
> there is no impact on the performance.
>
> Ebizzy:
> -------
> The test is counting the number of records per second it can manage, the
> higher is the best. I run it like this 'ebizzy -mTRp'. To get consistent
> result I repeated the test 100 times and measure the average result. The
> number is the record processes per second, the higher is the best.
>
> BASE SPF delta
> 16 CPUs x86 VM 14902.6 95905.16 543.55%
> 80 CPUs P8 node 37240.24 78185.67 109.95%
>
> Here are the performance counter read during a run on a 16 CPUs x86 VM:
> Performance counter stats for './ebizzy -mRTp':
> 888157 faults
> 884773 spf
> 92 pagefault:spf_pte_lock
> 2379 pagefault:spf_vma_changed
> 0 pagefault:spf_vma_noanon
> 80 pagefault:spf_vma_notsup
> 0 pagefault:spf_vma_access
> 0 pagefault:spf_pmd_changed
>
> And the ones captured during a run on a 80 CPUs Power node:
> Performance counter stats for './ebizzy -mRTp':
> 762134 faults
> 728663 spf
> 19101 pagefault:spf_pte_lock
> 13969 pagefault:spf_vma_changed
> 0 pagefault:spf_vma_noanon
> 272 pagefault:spf_vma_notsup
> 0 pagefault:spf_vma_access
> 0 pagefault:spf_pmd_changed
>
> In ebizzy's case most of the page fault were handled in a speculative way,
> leading the ebizzy performance boost.
We ported the SPF to kernel 4.9 in android devices.
For the app launch time, It improves about 15% average. For the apps
which have hundreds of threads, it will be about 20%.
Thanks.
>
> ------------------
> Changes since v8:
> - Don't check PMD when locking the pte when THP is disabled
> Thanks to Daniel Jordan for reporting this.
> - Rebase on 4.16
> Changes since v7:
> - move pte_map_lock() and pte_spinlock() upper in mm/memory.c (patch 4 &
> 5)
> - make pte_unmap_same() compatible with the speculative page fault (patch
> 6)
> Changes since v6:
> - Rename config variable to CONFIG_SPECULATIVE_PAGE_FAULT (patch 1)
> - Review the way the config variable is set (patch 1 to 3)
> - Introduce mm_rb_write_*lock() in mm/mmap.c (patch 18)
> - Merge patch introducing pte try locking in the patch 18.
> Changes since v5:
> - use rwlock agains the mm RB tree in place of SRCU
> - add a VMA's reference count to protect VMA while using it without
> holding the mmap_sem.
> - check PMD value to detect collapsing operation
> - don't try speculative page fault for mono threaded processes
> - try to reuse the fetched VMA if VM_RETRY is returned
> - go directly to the error path if an error is detected during the SPF
> path
> - fix race window when moving VMA in move_vma()
> Changes since v4:
> - As requested by Andrew Morton, use CONFIG_SPF and define it earlier in
> the series to ease bisection.
> Changes since v3:
> - Don't build when CONFIG_SMP is not set
> - Fixed a lock dependency warning in __vma_adjust()
> - Use READ_ONCE to access p*d values in handle_speculative_fault()
> - Call memcp_oom() service in handle_speculative_fault()
> Changes since v2:
> - Perf event is renamed in PERF_COUNT_SW_SPF
> - On Power handle do_page_fault()'s cleaning
> - On Power if the VM_FAULT_ERROR is returned by
> handle_speculative_fault(), do not retry but jump to the error path
> - If VMA's flags are not matching the fault, directly returns
> VM_FAULT_SIGSEGV and not VM_FAULT_RETRY
> - Check for pud_trans_huge() to avoid speculative path
> - Handles _vm_normal_page()'s introduced by 6f16211df3bf
> ("mm/device-public-memory: device memory cache coherent with CPU")
> - add and review few comments in the code
> Changes since v1:
> - Remove PERF_COUNT_SW_SPF_FAILED perf event.
> - Add tracing events to details speculative page fault failures.
> - Cache VMA fields values which are used once the PTE is unlocked at the
> end of the page fault events.
> - Ensure that fields read during the speculative path are written and read
> using WRITE_ONCE and READ_ONCE.
> - Add checks at the beginning of the speculative path to abort it if the
> VMA is known to not be supported.
> Changes since RFC V5 [5]
> - Port to 4.13 kernel
> - Merging patch fixing lock dependency into the original patch
> - Replace the 2 parameters of vma_has_changed() with the vmf pointer
> - In patch 7, don't call __do_fault() in the speculative path as it may
> want to unlock the mmap_sem.
> - In patch 11-12, don't check for vma boundaries when
> page_add_new_anon_rmap() is called during the spf path and protect against
> anon_vma pointer's update.
> - In patch 13-16, add performance events to report number of successful
> and failed speculative events.
>
> [1]
> http://linux-kernel.2935.n7.nabble.com/RFC-PATCH-0-6-Another-go-at-speculative-page-faults-tt965642.html#none
> [2] https://patchwork.kernel.org/patch/9999687/
>
>
> Laurent Dufour (20):
> mm: Introduce CONFIG_SPECULATIVE_PAGE_FAULT
> x86/mm: Define CONFIG_SPECULATIVE_PAGE_FAULT
> powerpc/mm: Define CONFIG_SPECULATIVE_PAGE_FAULT
> mm: Introduce pte_spinlock for FAULT_FLAG_SPECULATIVE
> mm: make pte_unmap_same compatible with SPF
> mm: Protect VMA modifications using VMA sequence count
> mm: protect mremap() against SPF hanlder
> mm: Protect SPF handler against anon_vma changes
> mm: Cache some VMA fields in the vm_fault structure
> mm/migrate: Pass vm_fault pointer to migrate_misplaced_page()
> mm: Introduce __lru_cache_add_active_or_unevictable
> mm: Introduce __maybe_mkwrite()
> mm: Introduce __vm_normal_page()
> mm: Introduce __page_add_new_anon_rmap()
> mm: Protect mm_rb tree with a rwlock
> mm: Adding speculative page fault failure trace events
> perf: Add a speculative page fault sw event
> perf tools: Add support for the SPF perf event
> mm: Speculative page fault handler return VMA
> powerpc/mm: Add speculative page fault
>
> Peter Zijlstra (4):
> mm: Prepare for FAULT_FLAG_SPECULATIVE
> mm: VMA sequence count
> mm: Provide speculative fault infrastructure
> x86/mm: Add speculative pagefault handling
>
> arch/powerpc/Kconfig | 1 +
> arch/powerpc/mm/fault.c | 31 +-
> arch/x86/Kconfig | 1 +
> arch/x86/mm/fault.c | 38 ++-
> fs/proc/task_mmu.c | 5 +-
> fs/userfaultfd.c | 17 +-
> include/linux/hugetlb_inline.h | 2 +-
> include/linux/migrate.h | 4 +-
> include/linux/mm.h | 92 +++++-
> include/linux/mm_types.h | 7 +
> include/linux/pagemap.h | 4 +-
> include/linux/rmap.h | 12 +-
> include/linux/swap.h | 10 +-
> include/trace/events/pagefault.h | 87 +++++
> include/uapi/linux/perf_event.h | 1 +
> kernel/fork.c | 3 +
> mm/Kconfig | 3 +
> mm/hugetlb.c | 2 +
> mm/init-mm.c | 3 +
> mm/internal.h | 20 ++
> mm/khugepaged.c | 5 +
> mm/madvise.c | 6 +-
> mm/memory.c | 594 ++++++++++++++++++++++++++++++----
> mm/mempolicy.c | 51 ++-
> mm/migrate.c | 4 +-
> mm/mlock.c | 13 +-
> mm/mmap.c | 211 +++++++++---
> mm/mprotect.c | 4 +-
> mm/mremap.c | 13 +
> mm/rmap.c | 5 +-
> mm/swap.c | 6 +-
> mm/swap_state.c | 8 +-
> tools/include/uapi/linux/perf_event.h | 1 +
> tools/perf/util/evsel.c | 1 +
> tools/perf/util/parse-events.c | 4 +
> tools/perf/util/parse-events.l | 1 +
> tools/perf/util/python.c | 1 +
> 37 files changed, 1097 insertions(+), 174 deletions(-)
> create mode 100644 include/trace/events/pagefault.h
>
> --
> 2.7.4
>
^ permalink raw reply
* Re: RFC on writel and writel_relaxed
From: Benjamin Herrenschmidt @ 2018-03-22 4:24 UTC (permalink / raw)
To: Sinan Kaya, Oliver
Cc: open list:LINUX FOR POWERPC (32-BIT AND 64-BIT),
linux-rdma@vger.kernel.org
In-Reply-To: <4e5c745a-8b9b-959e-8893-d99cd6032484@codeaurora.org>
On Wed, 2018-03-21 at 08:53 -0500, Sinan Kaya wrote:
> writel_relaxed() needs to have ordering guarantees with respect to the order
> device observes writes.
Correct.
> x86 has compiler barrier inside the relaxed() API so that code does not
> get reordered. ARM64 architecturally guarantees device writes to be observed
> in order.
>
> I was hoping that PPC could follow x86 and inject compiler barrier into the
> relaxed functions.
>
> BTW, I have no idea what compiler barrier does on PPC and if
>
> wrltel() == compiler barrier() + wrltel_relaxed()
>
> can be said.
No, it's not sufficient.
Replacing wmb() + writel() with wmb() + writel_relaxed() will work on
PPC, it will just not give you a benefit today.
The main problem is that the semantics of writel/writel_relaxed (and
read versions) aren't very well defined in Linux esp. when it comes
to different memory types (NC, WC, ...).
I've been wanting to implement the relaxed accessors for a while but
was battling with this to try to also better support WC, and due to
other commitments, this somewhat fell down the cracks.
Two options I can think of:
- Just make the _relaxed variants use an eieio instead of a sync, this
will effectively lift the ordering guarantee vs. cachable storage (and
thus unlock) and might give a (small) performance improvement. However,
we still have the problem that on WC mappings, neither writel nor
writel_relaxed will effectively allow combining to happen (only raw
accesses will because on powerpc *all* barriers will break combining).
- Make writel_relaxed() be a simple store without barriers, and
readl_relaxed() be "eieio, read, eieio", thus allowing write combining
to happen between successive writel_relaxed on WC space (no change on
normal NC space) while maintaining the ordering between relaxed reads
and writes. The flip side is a (slight) increased overhead of
readl_relaxed.
Cheers,
Ben.
^ permalink raw reply
* Re: DMA Mapping Error in ppc64
From: Oliver @ 2018-03-22 4:54 UTC (permalink / raw)
To: Jared Bents; +Cc: linuxppc-dev
In-Reply-To: <CAM=7fbcynhZ3iPtCGpVCgDmw7OU6SQcucZDm1kUdv=soky9RJQ@mail.gmail.com>
On Thu, Mar 22, 2018 at 8:00 AM, Jared Bents
<jared.bents@rockwellcollins.com> wrote:
> Hi all,
>
> Apologies for the amount of information but we've been debugging this
> for a while and I wanted to get what we are seeing captured as much as
> possible. We are a T1042 processor and have a total 8GB DDR and our
> kernel version is fsl-sdk-v2.0-1703 (linux v4.1.35) as that is the
> latest version supplied by NXP.
>
> A while ago we ported from 32 bit to 64 bit. Everything continued to
> work except the ath10k module we have. So as a first step, we checked
> to see if an ath9k module also failed to work and it was also no
> longer working. The ath10k is working fine on a 32 bit system but
> it's not working on 64 bit system as we are getting dma mapping errors
> when trying to initialize the wifi modules.
>
> pci_bus 0002:01: bus scan returning with max=01
> pci_bus 0002:01: busn_res: [bus 01] end is updated to 01
> pci_bus 0002:00: bus scan returning with max=01
> ath10k_pci 0000:01:00.0: unable to get target info from device
> ath10k_pci 0000:01:00.0: could not get target info (-5)
> ath10k_pci 0000:01:00.0: could not probe fw (-5)
> ath10k_pci 0001:01:00.0: Direct firmware load for
> ath10k/cal-pci-0001:01:00.0.bin failed with error -2
>
>
> First, we have tried the mainline kernel (v4.15) to see if that would
> fix the issue, it did not. So I made a patch for the ath10k driver to
> restrict to just GFP_DMA areas when allocating memory or creating
> sk_buffs and have attached it. The ath10k wifi modules now initialize
> correctly but when I try to connect them and send traffic, they get a
> DMA mapping error from the sk_buff that it receives from elsewhere in
> the kernel. So while the driver appears to be fixable with the patch,
> the modules are still unusable due to data being sent to the driver
> when ath10k_tx is called and it tries to dma map with the provided
> skb. Also, according to the ath10k mailing list, GFP_DMA is not
> supposed to be used in general. The error below is the same sort of
> dma mapping error that is seen when initializing the modules without
> the patch to OR with GFP_DMA.
>
> ath10k_pci 0001:01:00.0: failed to transmit packet, dropping: -5
>
>
> We asked on the ath10k mailing list if anyone else is having this
> problem and no one else seems to have the issue but they are using
> different architectures (ARM or X86). As a result, it does not seem to
> be a driver issue to us but something within the PowerPC arch. So we
> dug a little deeper to try to find what addresses being mapped are
> working and what address being mapped are not working.
>
> We found that when the virtual address of data pointer (a member of
> sk_buff) is above ~3.7 GB RAM address range then return address from
> dma_map_single API is failed to validate in dma_mapping_error
> function.
>
> We also noticed that in a 64bit machine sometimes ping is working and
> because of the virtual address is under ~3.7GAM RAM address range. So
> if we set mem=2048M in the bootargs, the ath10k module works
> perfectly, however this isn't a real solution since it cuts our
> available RAM from 8GB to 2GB.
I think there's a known issue with the freescale PCIe root complex
where it can't DMA beyond the 4GB mark. There's a workaround in
the form of limit_zone_pfn() which you can use to put the lower 4GB into
ZONE_DMA32 and allocate from there rather than ZONE_NORMAL.
For details of how to use it have a look at corenet_gen_setup_arch() in
arch/powerpc/platforms/85xx/corenet_generic.c
Hope that helps,
Oliver
^ permalink raw reply
* Re: RFC on writel and writel_relaxed
From: Oliver @ 2018-03-22 5:24 UTC (permalink / raw)
To: David Laight
Cc: Sinan Kaya, linux-rdma@vger.kernel.org,
open list:LINUX FOR POWERPC (32-BIT AND 64-BIT)
In-Reply-To: <8a13375fd8e5439890768b7dd8473099@AcuMS.aculab.com>
On Thu, Mar 22, 2018 at 1:35 AM, David Laight <David.Laight@aculab.com> wrote:
>> x86 has compiler barrier inside the relaxed() API so that code does not
>> get reordered. ARM64 architecturally guarantees device writes to be observed
>> in order.
>
> There are places where you don't even need a compile barrier between
> every write.
>
> I had horrid problems getting some ppc code (for a specific embedded SoC)
> optimised to have no extra barriers.
> I ended up just writing through 'pointer to volatile' and adding an
> explicit 'eieio' between the block of writes and status read.
This is what you are supposed to do. For accesses to MMIO (cache
inhibited + guarded) storage the Power ISA guarantees that load-load
and store-store pairs of accesses will always occur in program order,
but there's no implicit ordering between load-store or store-load
pairs. In those cases you need an explicit eieio barrier between the
two accesses. At the HW level you can think of the CPU as having
separate queues for MMIO loads and stores. Accesses will be added to
the respective queue in program order, but there's no synchronisation
between the two queues. If the CPU is doing write combining it's easy
to imagine the whole store queue being emptied in one big gulp before
the load queue is even touched.
> No less painful was doing a byteswapping write to normal memory.
What was the problem? The reverse indexed load/store instructions are
a little awkward to use, but they work...
>
> David
>
^ permalink raw reply
* Re: [bug?] Access was denied by memory protection keys in execute-only address
From: Ram Pai @ 2018-03-22 7:09 UTC (permalink / raw)
To: Li Wang
Cc: Michael Ellerman, Jan Stancek, ltp, linux-mm,
linuxppc-dev@lists.ozlabs.org
In-Reply-To: <CAEemH2eewab4nsn6daMRAtn9tDrHoZb_PnbH8xA17ypFCTg6iA@mail.gmail.com>
On Wed, Mar 21, 2018 at 02:53:00PM +0800, Li Wang wrote:
> On Wed, Mar 21, 2018 at 5:58 AM, Ram Pai <[1]linuxram@us.ibm.com> wrote:
>
> On Fri, Mar 09, 2018 at 11:43:00AM +0800, Li Wang wrote:
> > On Fri, Mar 9, 2018 at 12:45 AM, Ram Pai
> <[1][2]linuxram@us.ibm.com> wrote:
> >
> > On Thu, Mar 08, 2018 at 11:19:12PM +1100, Michael Ellerman wrote:
> > > Li Wang <[2][3]liwang@redhat.com> writes:
> > > > Hi,
> > > >
> > am wondering if the slightly different cpu behavior is dependent
..snip..
> on the
> > version of the firmware/microcode?
> >
> > I also run this reproducer on series ppc kvm machines, but none of
> them
> > get the FAIL.
> > If you need some more HW info, pls let me know.
>
> Hi Li,
>
> Can you try the following patch and see if it solves your problem.
>
> It only works on power7 lpar machine.
>
> But for p8 lpar, it still get failure as that before, the thing I wondered
> is
> that why not disable the pkey_execute_disable_supported on p8 machine?
It turns out to be a testcase bug. On Big endian powerpc ABI, function
ptrs are basically pointers to function descriptors. The testcase
copies functions which results in function descriptors getting copied.
You have to apply the following patch to your test case for it to
operate as intended. Thanks to Michael Ellermen for helping me out.
Otherwise I would be scratching my head for ever.
diff --git a/testcases/kernel/syscalls/mprotect/mprotect04.c b/testcases/kernel/syscalls/mprotect/mprotect04.c
index 1173afd..9fe9001 100644
--- a/testcases/kernel/syscalls/mprotect/mprotect04.c
+++ b/testcases/kernel/syscalls/mprotect/mprotect04.c
@@ -189,18 +189,30 @@ static void clear_cache(void *start, int len)
#endif
}
+typedef struct {
+ uintptr_t entry;
+ uintptr_t toc;
+ uintptr_t env;
+} func_descr_t;
+
+typedef void (*func_ptr_t)(void);
+
/*
* Copy page where &exec_func resides. Also try to copy subsequent page
* in case exec_func is close to page boundary.
*/
-static void *get_func(void *mem)
+void *get_func(void *mem)
{
uintptr_t page_sz = getpagesize();
uintptr_t page_mask = ~(page_sz - 1);
- uintptr_t func_page_offset = (uintptr_t)&exec_func & (page_sz - 1);
- void *func_copy_start = mem + func_page_offset;
- void *page_to_copy = (void *)((uintptr_t)&exec_func & page_mask);
+ uintptr_t func_page_offset;
+ void *func_copy_start, *page_to_copy;
void *mem_start = mem;
+ func_descr_t *opd = (func_descr_t *)&exec_func;
+
+ func_page_offset = (uintptr_t)opd->entry & (page_sz - 1);
+ func_copy_start = mem + func_page_offset;
+ page_to_copy = (void *)((uintptr_t)opd->entry & page_mask);
/* copy 1st page, if it's not present something is wrong */
if (!page_present(page_to_copy)) {
@@ -228,15 +240,17 @@ static void *get_func(void *mem)
static void testfunc_protexec(void)
{
- void (*func)(void);
void *p;
+ func_ptr_t func;
+ func_descr_t opd;
sig_caught = 0;
p = SAFE_MMAP(cleanup, 0, copy_sz, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- func = get_func(p);
+ opd.entry = (uintptr_t)get_func(p);
+ func = (func_ptr_t)&opd;
/* Change the protection to PROT_EXEC. */
TEST(mprotect(p, copy_sz, PROT_EXEC));
RP
^ permalink raw reply related
* Re: [PATCH v2 1/5] powerpc64/ftrace: Add a field in paca to disable ftrace in unsafe code paths
From: Naveen N. Rao @ 2018-03-22 7:53 UTC (permalink / raw)
To: Michael Ellerman, Paul Mackerras, Steven Rostedt
Cc: Anton Blanchard, linuxppc-dev, Nicholas Piggin, sathnaga
In-Reply-To: <b6aff6c7194bd7bb97828db63ca0c82ee4598918.1521627906.git.naveen.n.rao__49352. 2364100956$1521630977$gmane$org@linux.vnet.ibm.com>
Naveen N. Rao wrote:
> We have some C code that we call into from real mode where we cannot
> take any exceptions. Though the C functions themselves are mostly safe,
> if these functions are traced, there is a possibility that we may take
> an exception. For instance, in certain conditions, the ftrace code uses
> WARN(), which uses a 'trap' to do its job.
>=20
> For such scenarios, introduce a new field in paca 'ftrace_disabled',
> which is checked on ftrace entry before continuing. This field can then
> be set to a non-zero value to disable/pause ftrace, and reset to zero to
> resume ftrace.
>=20
> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> ---
> Changes since v1:
> - Do not guard the paca field check within CONFIG_KVM.
> - Move the early return code out of the usual path to optimize for=20
> better cache performance in the normal case when ftrace is enabled.
>=20
> arch/powerpc/include/asm/paca.h | 1 +
> arch/powerpc/kernel/asm-offsets.c | 1 +
> arch/powerpc/kernel/trace/ftrace_64_mprofile.S | 14 ++++++++++++++
> arch/powerpc/kernel/trace/ftrace_64_pg.S | 4 ++++
> 4 files changed, 20 insertions(+)
>=20
> diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/p=
aca.h
> index d2bf71dddbef..4f47adc2a408 100644
> --- a/arch/powerpc/include/asm/paca.h
> +++ b/arch/powerpc/include/asm/paca.h
> @@ -211,6 +211,7 @@ struct paca_struct {
> u16 in_mce;
> u8 hmi_event_available; /* HMI event is available */
> u8 hmi_p9_special_emu; /* HMI P9 special emulation */
> + u8 ftrace_disabled;
> #endif
> =20
> /* Stuff for accurate time accounting */
> diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-=
offsets.c
> index ea5eb91b836e..8e4fc96ff6bc 100644
> --- a/arch/powerpc/kernel/asm-offsets.c
> +++ b/arch/powerpc/kernel/asm-offsets.c
> @@ -240,6 +240,7 @@ int main(void)
> OFFSET(PACA_RFI_FLUSH_FALLBACK_AREA, paca_struct, rfi_flush_fallback_ar=
ea);
> OFFSET(PACA_EXRFI, paca_struct, exrfi);
> OFFSET(PACA_L1D_FLUSH_SIZE, paca_struct, l1d_flush_size);
> + OFFSET(PACA_FTRACE_DISABLED, paca_struct, ftrace_disabled);
> =20
> #endif
> OFFSET(PACAHWCPUID, paca_struct, hw_cpu_id);
> diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S b/arch/powerp=
c/kernel/trace/ftrace_64_mprofile.S
> index 3f3e81852422..8f2380304ef1 100644
> --- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
> +++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
> @@ -47,6 +47,12 @@ _GLOBAL(ftrace_caller)
> /* Save all gprs to pt_regs */
> SAVE_GPR(0, r1)
> SAVE_10GPRS(2, r1)
> +
> + /* Ok to continue? */
> + lbz r3, PACA_FTRACE_DISABLED(r13)
> + cmpdi r3, 0
> + beq ftrace_no_trace
^^^ bne
:facepalm:
- Naveen
=
^ permalink raw reply
* Re: RFC on writel and writel_relaxed
From: Gabriel Paubert @ 2018-03-22 8:20 UTC (permalink / raw)
To: Oliver
Cc: David Laight, Sinan Kaya, linux-rdma@vger.kernel.org,
open list:LINUX FOR POWERPC (32-BIT AND 64-BIT)
In-Reply-To: <CAOSf1CHTouXQ+sPxu7ySCtw--maef+knFC9bCQ7rpuk-hf-puQ@mail.gmail.com>
On Thu, Mar 22, 2018 at 04:24:24PM +1100, Oliver wrote:
> On Thu, Mar 22, 2018 at 1:35 AM, David Laight <David.Laight@aculab.com> wrote:
> >> x86 has compiler barrier inside the relaxed() API so that code does not
> >> get reordered. ARM64 architecturally guarantees device writes to be observed
> >> in order.
> >
> > There are places where you don't even need a compile barrier between
> > every write.
> >
> > I had horrid problems getting some ppc code (for a specific embedded SoC)
> > optimised to have no extra barriers.
> > I ended up just writing through 'pointer to volatile' and adding an
> > explicit 'eieio' between the block of writes and status read.
>
> This is what you are supposed to do. For accesses to MMIO (cache
> inhibited + guarded) storage the Power ISA guarantees that load-load
> and store-store pairs of accesses will always occur in program order,
> but there's no implicit ordering between load-store or store-load
And even for load store, eieio is not always necessary, in the important
case of reading and writing to the same address, when modifying bits in
a control register for example.
Typically also loads will be moved ahead of stores, but not the other
way around, so in practice you won't notice a missed eieio in this case.
This does not mean you should not insert it.
> pairs. In those cases you need an explicit eieio barrier between the
> two accesses. At the HW level you can think of the CPU as having
> separate queues for MMIO loads and stores. Accesses will be added to
> the respective queue in program order, but there's no synchronisation
> between the two queues. If the CPU is doing write combining it's easy
> to imagine the whole store queue being emptied in one big gulp before
> the load queue is even touched.
Is write combining allowed on guarded storage?
<Looking at docs>
>From PowerISA_V3.0.pdf, Book2, section 1.6.2 "Caching inhibited":
"No combining occurs if the storage is also Guarded"
Gabriel
^ permalink raw reply
* [PATCH V2] powerpc/mm/radix: Update pte fragment count from 16 to 256 on radix
From: Aneesh Kumar K.V @ 2018-03-22 8:43 UTC (permalink / raw)
To: benh, paulus, mpe; +Cc: linuxppc-dev, Aneesh Kumar K.V
Right now we use only 4K out of the 64k page allocated for the level 4 page
table. W.r.t the performance impact due to lock contention, with ebizzy
256 threads:
without patch (10 runs of ./ebizzy -m -n 1000 -s 131072 -S 100)
median = 15678.5
stdev = 42.1209
with patch:
median = 15354
stdev = 194.743
This is with THP disabled. With THP enabled the impact of the patch will be less.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/book3s/64/hash-64k.h | 10 ++++------
arch/powerpc/include/asm/book3s/64/radix-4k.h | 5 +++++
arch/powerpc/include/asm/book3s/64/radix-64k.h | 6 ++++++
arch/powerpc/mm/pgtable-radix.c | 8 ++------
4 files changed, 17 insertions(+), 12 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
index 3bcf269f8f55..0aa4f755b3f6 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
@@ -24,16 +24,14 @@
/* PTE flags to conserve for HPTE identification */
#define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_HASHPTE | H_PAGE_COMBO)
-/*
- * we support 16 fragments per PTE page of 64K size.
- */
-#define H_PTE_FRAG_NR 16
/*
* We use a 2K PTE page fragment and another 2K for storing
* real_pte_t hash index
+ * 8 bytes per each pte entry and another 8 bytes for storing
+ * slot details.
*/
-#define H_PTE_FRAG_SIZE_SHIFT 12
-#define PTE_FRAG_SIZE (1UL << PTE_FRAG_SIZE_SHIFT)
+#define H_PTE_FRAG_SIZE_SHIFT (H_PTE_INDEX_SIZE + 3 + 1)
+#define H_PTE_FRAG_NR (PAGE_SIZE >> H_PTE_FRAG_SIZE_SHIFT)
#ifndef __ASSEMBLY__
#include <asm/errno.h>
diff --git a/arch/powerpc/include/asm/book3s/64/radix-4k.h b/arch/powerpc/include/asm/book3s/64/radix-4k.h
index a61aa9cd63ec..ca366ec86310 100644
--- a/arch/powerpc/include/asm/book3s/64/radix-4k.h
+++ b/arch/powerpc/include/asm/book3s/64/radix-4k.h
@@ -9,5 +9,10 @@
#define RADIX_PMD_INDEX_SIZE 9 /* 1G huge page */
#define RADIX_PUD_INDEX_SIZE 9
#define RADIX_PGD_INDEX_SIZE 13
+/*
+ * One fragment per per page
+ */
+#define RADIX_PTE_FRAG_SIZE_SHIFT (RADIX_PTE_INDEX_SIZE + 3)
+#define RADIX_PTE_FRAG_NR (PAGE_SIZE >> RADIX_PTE_FRAG_SIZE_SHIFT)
#endif /* _ASM_POWERPC_PGTABLE_RADIX_4K_H */
diff --git a/arch/powerpc/include/asm/book3s/64/radix-64k.h b/arch/powerpc/include/asm/book3s/64/radix-64k.h
index c7e71ba29555..830082496876 100644
--- a/arch/powerpc/include/asm/book3s/64/radix-64k.h
+++ b/arch/powerpc/include/asm/book3s/64/radix-64k.h
@@ -10,4 +10,10 @@
#define RADIX_PUD_INDEX_SIZE 9
#define RADIX_PGD_INDEX_SIZE 13
+/*
+ * We use a 256 byte PTE page fragment in radix
+ * 8 bytes per each PTE entry.
+ */
+#define RADIX_PTE_FRAG_SIZE_SHIFT (RADIX_PTE_INDEX_SIZE + 3)
+#define RADIX_PTE_FRAG_NR (PAGE_SIZE >> RADIX_PTE_FRAG_SIZE_SHIFT)
#endif /* _ASM_POWERPC_PGTABLE_RADIX_64K_H */
diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c
index 2e10a964e290..7fd51549b9e5 100644
--- a/arch/powerpc/mm/pgtable-radix.c
+++ b/arch/powerpc/mm/pgtable-radix.c
@@ -575,12 +575,8 @@ void __init radix__early_init_mmu(void)
#ifdef CONFIG_PCI
pci_io_base = ISA_IO_BASE;
#endif
-
- /*
- * For now radix also use the same frag size
- */
- __pte_frag_nr = H_PTE_FRAG_NR;
- __pte_frag_size_shift = H_PTE_FRAG_SIZE_SHIFT;
+ __pte_frag_nr = RADIX_PTE_FRAG_NR;
+ __pte_frag_size_shift = RADIX_PTE_FRAG_SIZE_SHIFT;
if (!firmware_has_feature(FW_FEATURE_LPAR)) {
radix_init_native();
--
2.14.3
^ permalink raw reply related
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