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From: Mike Rapoport <rppt@linux.vnet.ibm.com>
To: Jonathan Corbet <corbet@lwn.net>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>,
	Richard Henderson <rth@twiddle.net>,
	Ivan Kokshaysky <ink@jurassic.park.msu.ru>,
	Matt Turner <mattst88@gmail.com>, Tony Luck <tony.luck@intel.com>,
	Fenghua Yu <fenghua.yu@intel.com>,
	Ralf Baechle <ralf@linux-mips.org>,
	James Hogan <jhogan@kernel.org>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
	kasan-dev@googlegroups.com, linux-alpha@vger.kernel.org,
	linux-ia64@vger.kernel.org, linux-mips@linux-mips.org,
	linuxppc-dev@lists.ozlabs.org, linux-fsdevel@vger.kernel.org,
	linux-mm@kvack.org, Mike Rapoport <rppt@linux.vnet.ibm.com>
Subject: [PATCH 12/32] docs/vm: mmu_notifier.txt: convert to ReST format
Date: Wed, 21 Mar 2018 21:22:28 +0200	[thread overview]
Message-ID: <1521660168-14372-13-git-send-email-rppt@linux.vnet.ibm.com> (raw)
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/mmu_notifier.txt | 108 ++++++++++++++++++++------------------
 1 file changed, 57 insertions(+), 51 deletions(-)

diff --git a/Documentation/vm/mmu_notifier.txt b/Documentation/vm/mmu_notifier.txt
index 23b4625..47baa1c 100644
--- a/Documentation/vm/mmu_notifier.txt
+++ b/Documentation/vm/mmu_notifier.txt
@@ -1,7 +1,10 @@
+.. _mmu_notifier:
+
 When do you need to notify inside page table lock ?
+===================================================
 
 When clearing a pte/pmd we are given a choice to notify the event through
-(notify version of *_clear_flush call mmu_notifier_invalidate_range) under
+(notify version of \*_clear_flush call mmu_notifier_invalidate_range) under
 the page table lock. But that notification is not necessary in all cases.
 
 For secondary TLB (non CPU TLB) like IOMMU TLB or device TLB (when device use
@@ -18,6 +21,7 @@ a page that might now be used by some completely different task.
 
 Case B is more subtle. For correctness it requires the following sequence to
 happen:
+
   - take page table lock
   - clear page table entry and notify ([pmd/pte]p_huge_clear_flush_notify())
   - set page table entry to point to new page
@@ -28,58 +32,60 @@ the device.
 
 Consider the following scenario (device use a feature similar to ATS/PASID):
 
-Two address addrA and addrB such that |addrA - addrB| >= PAGE_SIZE we assume
+Two address addrA and addrB such that \|addrA - addrB\| >= PAGE_SIZE we assume
 they are write protected for COW (other case of B apply too).
 
-[Time N] --------------------------------------------------------------------
-CPU-thread-0  {try to write to addrA}
-CPU-thread-1  {try to write to addrB}
-CPU-thread-2  {}
-CPU-thread-3  {}
-DEV-thread-0  {read addrA and populate device TLB}
-DEV-thread-2  {read addrB and populate device TLB}
-[Time N+1] ------------------------------------------------------------------
-CPU-thread-0  {COW_step0: {mmu_notifier_invalidate_range_start(addrA)}}
-CPU-thread-1  {COW_step0: {mmu_notifier_invalidate_range_start(addrB)}}
-CPU-thread-2  {}
-CPU-thread-3  {}
-DEV-thread-0  {}
-DEV-thread-2  {}
-[Time N+2] ------------------------------------------------------------------
-CPU-thread-0  {COW_step1: {update page table to point to new page for addrA}}
-CPU-thread-1  {COW_step1: {update page table to point to new page for addrB}}
-CPU-thread-2  {}
-CPU-thread-3  {}
-DEV-thread-0  {}
-DEV-thread-2  {}
-[Time N+3] ------------------------------------------------------------------
-CPU-thread-0  {preempted}
-CPU-thread-1  {preempted}
-CPU-thread-2  {write to addrA which is a write to new page}
-CPU-thread-3  {}
-DEV-thread-0  {}
-DEV-thread-2  {}
-[Time N+3] ------------------------------------------------------------------
-CPU-thread-0  {preempted}
-CPU-thread-1  {preempted}
-CPU-thread-2  {}
-CPU-thread-3  {write to addrB which is a write to new page}
-DEV-thread-0  {}
-DEV-thread-2  {}
-[Time N+4] ------------------------------------------------------------------
-CPU-thread-0  {preempted}
-CPU-thread-1  {COW_step3: {mmu_notifier_invalidate_range_end(addrB)}}
-CPU-thread-2  {}
-CPU-thread-3  {}
-DEV-thread-0  {}
-DEV-thread-2  {}
-[Time N+5] ------------------------------------------------------------------
-CPU-thread-0  {preempted}
-CPU-thread-1  {}
-CPU-thread-2  {}
-CPU-thread-3  {}
-DEV-thread-0  {read addrA from old page}
-DEV-thread-2  {read addrB from new page}
+::
+
+ [Time N] --------------------------------------------------------------------
+ CPU-thread-0  {try to write to addrA}
+ CPU-thread-1  {try to write to addrB}
+ CPU-thread-2  {}
+ CPU-thread-3  {}
+ DEV-thread-0  {read addrA and populate device TLB}
+ DEV-thread-2  {read addrB and populate device TLB}
+ [Time N+1] ------------------------------------------------------------------
+ CPU-thread-0  {COW_step0: {mmu_notifier_invalidate_range_start(addrA)}}
+ CPU-thread-1  {COW_step0: {mmu_notifier_invalidate_range_start(addrB)}}
+ CPU-thread-2  {}
+ CPU-thread-3  {}
+ DEV-thread-0  {}
+ DEV-thread-2  {}
+ [Time N+2] ------------------------------------------------------------------
+ CPU-thread-0  {COW_step1: {update page table to point to new page for addrA}}
+ CPU-thread-1  {COW_step1: {update page table to point to new page for addrB}}
+ CPU-thread-2  {}
+ CPU-thread-3  {}
+ DEV-thread-0  {}
+ DEV-thread-2  {}
+ [Time N+3] ------------------------------------------------------------------
+ CPU-thread-0  {preempted}
+ CPU-thread-1  {preempted}
+ CPU-thread-2  {write to addrA which is a write to new page}
+ CPU-thread-3  {}
+ DEV-thread-0  {}
+ DEV-thread-2  {}
+ [Time N+3] ------------------------------------------------------------------
+ CPU-thread-0  {preempted}
+ CPU-thread-1  {preempted}
+ CPU-thread-2  {}
+ CPU-thread-3  {write to addrB which is a write to new page}
+ DEV-thread-0  {}
+ DEV-thread-2  {}
+ [Time N+4] ------------------------------------------------------------------
+ CPU-thread-0  {preempted}
+ CPU-thread-1  {COW_step3: {mmu_notifier_invalidate_range_end(addrB)}}
+ CPU-thread-2  {}
+ CPU-thread-3  {}
+ DEV-thread-0  {}
+ DEV-thread-2  {}
+ [Time N+5] ------------------------------------------------------------------
+ CPU-thread-0  {preempted}
+ CPU-thread-1  {}
+ CPU-thread-2  {}
+ CPU-thread-3  {}
+ DEV-thread-0  {read addrA from old page}
+ DEV-thread-2  {read addrB from new page}
 
 So here because at time N+2 the clear page table entry was not pair with a
 notification to invalidate the secondary TLB, the device see the new value for
-- 
2.7.4

  parent reply	other threads:[~2018-03-21 19:22 UTC|newest]

Thread overview: 41+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-21 19:22 [PATCH 00/32] docs/vm: convert to ReST format Mike Rapoport
2018-03-21 19:22 ` [PATCH 01/32] docs/vm: active_mm.txt " Mike Rapoport
2018-03-21 19:22 ` [PATCH 02/32] docs/vm: balance: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 03/32] docs/vm: cleancache.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 04/32] docs/vm: frontswap.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 05/32] docs/vm: highmem.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 06/32] docs/vm: hmm.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 07/32] docs/vm: hugetlbpage.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 08/32] docs/vm: hugetlbfs_reserv.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 09/32] docs/vm: hwpoison.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 10/32] docs/vm: idle_page_tracking.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 11/32] docs/vm: ksm.txt: " Mike Rapoport
2018-03-21 19:22 ` Mike Rapoport [this message]
2018-03-21 19:22 ` [PATCH 13/32] docs/vm: numa_memory_policy.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 14/32] docs/vm: overcommit-accounting: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 15/32] docs/vm: page_frags " Mike Rapoport
2018-03-21 19:22 ` [PATCH 16/32] docs/vm: numa: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 17/32] docs/vm: pagemap.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 18/32] docs/vm: page_migration: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 19/32] docs/vm: page_owner: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 20/32] docs/vm: remap_file_pages.txt: conert " Mike Rapoport
2018-03-21 19:22 ` [PATCH 21/32] docs/vm: slub.txt: convert " Mike Rapoport
2018-03-21 19:22 ` [PATCH 22/32] docs/vm: soft-dirty.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 23/32] docs/vm: split_page_table_lock: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 24/32] docs/vm: swap_numa.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 25/32] docs/vm: transhuge.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 26/32] docs/vm: unevictable-lru.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 27/32] docs/vm: userfaultfd.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 28/32] docs/vm: z3fold.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 29/32] docs/vm: zsmalloc.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 30/32] docs/vm: zswap.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 31/32] docs/vm: rename documentation files to .rst Mike Rapoport
2018-03-21 19:22 ` [PATCH 32/32] docs/vm: add index.rst and link MM documentation to top level index Mike Rapoport
2018-03-29 21:46 ` [PATCH 00/32] docs/vm: convert to ReST format Jonathan Corbet
2018-04-01  6:38   ` Mike Rapoport
2018-04-10 10:23     ` Mike Rapoport
2018-04-13 19:55     ` Jonathan Corbet
2018-04-13 20:21       ` Matthew Wilcox
2018-04-15 17:29         ` Mike Rapoport
2018-04-15 17:36       ` Mike Rapoport
2018-04-16 20:35         ` Jonathan Corbet

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