[patch for 2.6.26 5/7] LTTng instrumentation mm

Mathieu Desnoyers
2008-03-27T13:32:45Z

[-- Attachment #1: lttng-instrumentation-mm.patch --]
[-- Type: text/plain, Size: 9773 bytes --]

Memory management core events.

Added markers :

mm_filemap_wait_end
mm_filemap_wait_start
mm_handle_fault_entry
mm_handle_fault_exit
mm_huge_page_alloc
mm_huge_page_free
mm_page_alloc
mm_page_free
mm_swap_file_close
mm_swap_file_open
mm_swap_in
mm_swap_out
statedump_swap_files

Changelog:
- Use page_to_pfn for swap out instrumentation, wait_on_page_bit, do_swap_page,
page alloc/free.
- add missing free_hot_cold_page instrumentation.
- add hugetlb page_alloc page_free instrumentation.
- Add write_access to mm fault.
- Add page bit_nr waited for by wait_on_page_bit.
- Move page alloc instrumentation to __aloc_pages so we cover the alloc zeroed
page path.
- Add swap file used for swap in and swap out events.
- Dump the swap files, instrument swapon and swapoff.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: linux-mm@kvack.org
CC: Dave Hansen <haveblue@us.ibm.com>
---
include/linux/swapops.h | 8 ++++++++
mm/filemap.c | 7 +++++++
mm/hugetlb.c | 3 +++
mm/memory.c | 39 ++++++++++++++++++++++++++++++---------
mm/page_alloc.c | 9 +++++++++
mm/page_io.c | 6 ++++++
mm/swapfile.c | 23 +++++++++++++++++++++++
7 files changed, 86 insertions(+), 9 deletions(-)

Index: linux-2.6-lttng/mm/filemap.c
===================================================================
--- linux-2.6-lttng.orig/mm/filemap.c 2008-03-27 09:18:44.000000000 -0400
+++ linux-2.6-lttng/mm/filemap.c 2008-03-27 09:19:23.000000000 -0400
@@ -33,6 +33,7 @@
#include <linux/cpuset.h>
#include <linux/hardirq.h> /* for BUG_ON(!in_atomic()) only */
#include <linux/memcontrol.h>
+#include <linux/marker.h>
#include "internal.h"

/*
@@ -540,9 +541,15 @@ void wait_on_page_bit(struct page *page,
{
DEFINE_WAIT_BIT(wait, &page->flags, bit_nr);

+ trace_mark(mm_filemap_wait_start, "pfn %lu bit_nr %d",
+ page_to_pfn(page), bit_nr);
+
if (test_bit(bit_nr, &page->flags))
__wait_on_bit(page_waitqueue(page), &wait, sync_page,
TASK_UNINTERRUPTIBLE);
+
+ trace_mark(mm_filemap_wait_end, "pfn %lu bit_nr %d",
+ page_to_pfn(page), bit_nr);
}
EXPORT_SYMBOL(wait_on_page_bit);

Index: linux-2.6-lttng/mm/memory.c
===================================================================
--- linux-2.6-lttng.orig/mm/memory.c 2008-03-27 09:18:44.000000000 -0400
+++ linux-2.6-lttng/mm/memory.c 2008-03-27 09:19:23.000000000 -0400
@@ -45,6 +45,7 @@
#include <linux/swap.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
+#include <linux/marker.h>
#include <linux/rmap.h>
#include <linux/module.h>
#include <linux/delayacct.h>
@@ -2050,6 +2051,10 @@ static int do_swap_page(struct mm_struct
/* Had to read the page from swap area: Major fault */
ret = VM_FAULT_MAJOR;
count_vm_event(PGMAJFAULT);
+ trace_mark(mm_swap_in, "pfn %lu filp %p offset %lu",
+ page_to_pfn(page),
+ get_swap_info_struct(swp_type(entry))->swap_file,
+ swp_offset(entry));
}

if (mem_cgroup_charge(page, mm, GFP_KERNEL)) {
@@ -2509,30 +2514,46 @@ unlock:
int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, int write_access)
{
+ int res;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;

+ trace_mark(mm_handle_fault_entry,
+ "address %lu ip #p%ld write_access %d",
+ address, KSTK_EIP(current), write_access);
+
__set_current_state(TASK_RUNNING);

count_vm_event(PGFAULT);

- if (unlikely(is_vm_hugetlb_page(vma)))
- return hugetlb_fault(mm, vma, address, write_access);
+ if (unlikely(is_vm_hugetlb_page(vma))) {
+ res = hugetlb_fault(mm, vma, address, write_access);
+ goto end;
+ }

pgd = pgd_offset(mm, address);
pud = pud_alloc(mm, pgd, address);
- if (!pud)
- return VM_FAULT_OOM;
+ if (!pud) {
+ res = VM_FAULT_OOM;
+ goto end;
+ }
pmd = pmd_alloc(mm, pud, address);
- if (!pmd)
- return VM_FAULT_OOM;
+ if (!pmd) {
+ res = VM_FAULT_OOM;
+ goto end;
+ }
pte = pte_alloc_map(mm, pmd, address);
- if (!pte)
- return VM_FAULT_OOM;
+ if (!pte) {
+ res = VM_FAULT_OOM;
+ goto end;
+ }

- return handle_pte_fault(mm, vma, address, pte, pmd, write_access);
+ res = handle_pte_fault(mm, vma, address, pte, pmd, write_access);
+end:
+ trace_mark(mm_handle_fault_exit, MARK_NOARGS);
+ return res;
}

#ifndef __PAGETABLE_PUD_FOLDED
Index: linux-2.6-lttng/mm/page_alloc.c
===================================================================
--- linux-2.6-lttng.orig/mm/page_alloc.c 2008-03-27 09:18:44.000000000 -0400
+++ linux-2.6-lttng/mm/page_alloc.c 2008-03-27 09:19:23.000000000 -0400
@@ -45,6 +45,7 @@
#include <linux/fault-inject.h>
#include <linux/page-isolation.h>
#include <linux/memcontrol.h>
+#include <linux/marker.h>

#include <asm/tlbflush.h>
#include <asm/div64.h>
@@ -527,6 +528,9 @@ static void __free_pages_ok(struct page
int i;
int reserved = 0;

+ trace_mark(mm_page_free, "order %u pfn %lu",
+ order, page_to_pfn(page));
+
for (i = 0 ; i < (1 << order) ; ++i)
reserved += free_pages_check(page + i);
if (reserved)
@@ -990,6 +994,8 @@ static void free_hot_cold_page(struct pa
struct per_cpu_pages *pcp;
unsigned long flags;

+ trace_mark(mm_page_free, "order %u pfn %lu", 0, page_to_pfn(page));
+
if (PageAnon(page))
page->mapping = NULL;
if (free_pages_check(page))
@@ -1643,6 +1649,9 @@ nopage:
show_mem();
}
got_pg:
+ if (page)
+ trace_mark(mm_page_alloc, "order %u pfn %lu", order,
+ page_to_pfn(page));
return page;
}

Index: linux-2.6-lttng/mm/page_io.c
===================================================================
--- linux-2.6-lttng.orig/mm/page_io.c 2008-03-27 09:18:44.000000000 -0400
+++ linux-2.6-lttng/mm/page_io.c 2008-03-27 09:19:23.000000000 -0400
@@ -17,6 +17,7 @@
#include <linux/bio.h>
#include <linux/swapops.h>
#include <linux/writeback.h>
+#include <linux/marker.h>
#include <asm/pgtable.h>

static struct bio *get_swap_bio(gfp_t gfp_flags, pgoff_t index,
@@ -114,6 +115,11 @@ int swap_writepage(struct page *page, st
rw |= (1 << BIO_RW_SYNC);
count_vm_event(PSWPOUT);
set_page_writeback(page);
+ trace_mark(mm_swap_out, "pfn %lu filp %p offset %lu",
+ page_to_pfn(page),
+ get_swap_info_struct(swp_type(
+ page_swp_entry(page)))->swap_file,
+ swp_offset(page_swp_entry(page)));
unlock_page(page);
submit_bio(rw, bio);
out:
Index: linux-2.6-lttng/mm/hugetlb.c
===================================================================
--- linux-2.6-lttng.orig/mm/hugetlb.c 2008-03-27 09:18:44.000000000 -0400
+++ linux-2.6-lttng/mm/hugetlb.c 2008-03-27 09:19:23.000000000 -0400
@@ -14,6 +14,7 @@
#include <linux/mempolicy.h>
#include <linux/cpuset.h>
#include <linux/mutex.h>
+#include <linux/marker.h>

#include <asm/page.h>
#include <asm/pgtable.h>
@@ -137,6 +138,7 @@ static void free_huge_page(struct page *
int nid = page_to_nid(page);
struct address_space *mapping;

+ trace_mark(mm_huge_page_free, "pfn %lu", page_to_pfn(page));
mapping = (struct address_space *) page_private(page);
set_page_private(page, 0);
BUG_ON(page_count(page));
@@ -485,6 +487,7 @@ static struct page *alloc_huge_page(stru
if (!IS_ERR(page)) {
set_page_refcounted(page);
set_page_private(page, (unsigned long) mapping);
+ trace_mark(mm_huge_page_alloc, "pfn %lu", page_to_pfn(page));
}
return page;
}
Index: linux-2.6-lttng/include/linux/swapops.h
===================================================================
--- linux-2.6-lttng.orig/include/linux/swapops.h 2008-03-27 09:18:44.000000000 -0400
+++ linux-2.6-lttng/include/linux/swapops.h 2008-03-27 09:19:23.000000000 -0400
@@ -76,6 +76,14 @@ static inline pte_t swp_entry_to_pte(swp
return __swp_entry_to_pte(arch_entry);
}

+static inline swp_entry_t page_swp_entry(struct page *page)
+{
+ swp_entry_t entry;
+ VM_BUG_ON(!PageSwapCache(page));
+ entry.val = page_private(page);
+ return entry;
+}
+
#ifdef CONFIG_MIGRATION
static inline swp_entry_t make_migration_entry(struct page *page, int write)
{
Index: linux-2.6-lttng/mm/swapfile.c
===================================================================
--- linux-2.6-lttng.orig/mm/swapfile.c 2008-03-27 09:18:44.000000000 -0400
+++ linux-2.6-lttng/mm/swapfile.c 2008-03-27 09:19:43.000000000 -0400
@@ -28,6 +28,7 @@
#include <linux/capability.h>
#include <linux/syscalls.h>
#include <linux/memcontrol.h>
+#include <linux/marker.h>

#include <asm/pgtable.h>
#include <asm/tlbflush.h>
@@ -1310,6 +1311,7 @@ asmlinkage long sys_swapoff(const char _
swap_map = p->swap_map;
p->swap_map = NULL;
p->flags = 0;
+ trace_mark(mm_swap_file_close, "filp %p", swap_file);
spin_unlock(&swap_lock);
mutex_unlock(&swapon_mutex);
vfree(swap_map);
@@ -1691,6 +1693,8 @@ asmlinkage long sys_swapon(const char __
} else {
swap_info[prev].next = p - swap_info;
}
+ trace_mark(mm_swap_file_open, "filp %p filename %s",
+ swap_file, name);
spin_unlock(&swap_lock);
mutex_unlock(&swapon_mutex);
error = 0;
@@ -1844,3 +1848,22 @@ int valid_swaphandles(swp_entry_t entry,
*offset = ++toff;
return nr_pages? ++nr_pages: 0;
}
+
+void ltt_dump_swap_files(void *call_data)
+{
+ int type;
+ struct swap_info_struct *p = NULL;
+
+ mutex_lock(&swapon_mutex);
+ for (type = swap_list.head; type >= 0; type = swap_info[type].next) {
+ p = swap_info + type;
+ if ((p->flags & SWP_ACTIVE) != SWP_ACTIVE)
+ continue;
+ __trace_mark(0, statedump_swap_files, call_data,
+ "filp %p vfsmount %p dname %s",
+ p->swap_file, p->swap_file->f_vfsmnt,
+ p->swap_file->f_dentry->d_name.name);
+ }
+ mutex_unlock(&swapon_mutex);
+}
+EXPORT_SYMBOL_GPL(ltt_dump_swap_files);

--
Mathieu Desnoyers
Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68