[RFC 5/7] LTTng instrumentation mm

Mathieu Desnoyers
2007-11-13T19:41:35Z

[-- Attachment #1: lttng-instrumentation-mm.patch --]
[-- Type: text/plain, Size: 4322 bytes --]

Memory management core events.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: linux-mm@kvack.org
---
mm/filemap.c | 4 ++++
mm/memory.c | 34 +++++++++++++++++++++++++---------
mm/page_alloc.c | 5 +++++
mm/page_io.c | 1 +
4 files changed, 35 insertions(+), 9 deletions(-)

Index: linux-2.6-lttng/mm/filemap.c
===================================================================
--- linux-2.6-lttng.orig/mm/filemap.c 2007-11-13 09:25:26.000000000 -0500
+++ linux-2.6-lttng/mm/filemap.c 2007-11-13 09:49:35.000000000 -0500
@@ -514,9 +514,13 @@ void fastcall wait_on_page_bit(struct pa
{
DEFINE_WAIT_BIT(wait, &page->flags, bit_nr);

+ trace_mark(mm_filemap_wait_start, "address %p", page_address(page));
+
if (test_bit(bit_nr, &page->flags))
__wait_on_bit(page_waitqueue(page), &wait, sync_page,
TASK_UNINTERRUPTIBLE);
+
+ trace_mark(mm_filemap_wait_end, "address %p", page_address(page));
}
EXPORT_SYMBOL(wait_on_page_bit);

Index: linux-2.6-lttng/mm/memory.c
===================================================================
--- linux-2.6-lttng.orig/mm/memory.c 2007-11-13 09:45:41.000000000 -0500
+++ linux-2.6-lttng/mm/memory.c 2007-11-13 09:49:35.000000000 -0500
@@ -2072,6 +2072,7 @@ static int do_swap_page(struct mm_struct
delayacct_set_flag(DELAYACCT_PF_SWAPIN);
page = lookup_swap_cache(entry);
if (!page) {
+ trace_mark(mm_swap_in, "address #p%lu", address);
grab_swap_token(); /* Contend for token _before_ read-in */
swapin_readahead(entry, address, vma);
page = read_swap_cache_async(entry, vma, address);
@@ -2526,30 +2527,45 @@ 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",
+ address, KSTK_EIP(current));
+
__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 2007-11-13 09:25:26.000000000 -0500
+++ linux-2.6-lttng/mm/page_alloc.c 2007-11-13 09:49:35.000000000 -0500
@@ -519,6 +519,9 @@ static void __free_pages_ok(struct page
int i;
int reserved = 0;

+ trace_mark(mm_page_free, "order %u address %p",
+ order, page_address(page));
+
for (i = 0 ; i < (1 << order) ; ++i)
reserved += free_pages_check(page + i);
if (reserved)
@@ -1639,6 +1642,8 @@ fastcall unsigned long __get_free_pages(
page = alloc_pages(gfp_mask, order);
if (!page)
return 0;
+ trace_mark(mm_page_alloc, "order %u address %p",
+ order, page_address(page));
return (unsigned long) page_address(page);
}

Index: linux-2.6-lttng/mm/page_io.c
===================================================================
--- linux-2.6-lttng.orig/mm/page_io.c 2007-11-13 09:25:26.000000000 -0500
+++ linux-2.6-lttng/mm/page_io.c 2007-11-13 09:49:35.000000000 -0500
@@ -114,6 +114,7 @@ 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, "address %p", page_address(page));
unlock_page(page);
submit_bio(rw, bio);