mm, shmem: add internal shmem resident memory accounting

Currently looking at /proc/<pid>/status or statm, there is no way to
distinguish shmem pages from pages mapped to a regular file (shmem pages
are mapped to /dev/zero), even though their implication in actual memory
use is quite different.

The internal accounting currently counts shmem pages together with
regular files.  As a preparation to extend the userspace interfaces,
this patch adds MM_SHMEMPAGES counter to mm_rss_stat to account for
shmem pages separately from MM_FILEPAGES.  The next patch will expose it
to userspace - this patch doesn't change the exported values yet, by
adding up MM_SHMEMPAGES to MM_FILEPAGES at places where MM_FILEPAGES was
used before.  The only user-visible change after this patch is the OOM
killer message that separates the reported "shmem-rss" from "file-rss".

[vbabka@suse.cz: forward-porting, tweak changelog]
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Jerome Marchand 2016-01-14 15:19:26 -08:00 committed by Linus Torvalds
parent 48131e03ca
commit eca56ff906
8 changed files with 41 additions and 41 deletions

View file

@ -603,10 +603,7 @@ static void gmap_zap_swap_entry(swp_entry_t entry, struct mm_struct *mm)
else if (is_migration_entry(entry)) {
struct page *page = migration_entry_to_page(entry);
if (PageAnon(page))
dec_mm_counter(mm, MM_ANONPAGES);
else
dec_mm_counter(mm, MM_FILEPAGES);
dec_mm_counter(mm, mm_counter(page));
}
free_swap_and_cache(entry);
}

View file

@ -83,7 +83,8 @@ unsigned long task_statm(struct mm_struct *mm,
unsigned long *shared, unsigned long *text,
unsigned long *data, unsigned long *resident)
{
*shared = get_mm_counter(mm, MM_FILEPAGES);
*shared = get_mm_counter(mm, MM_FILEPAGES) +
get_mm_counter(mm, MM_SHMEMPAGES);
*text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
>> PAGE_SHIFT;
*data = mm->total_vm - mm->shared_vm;

View file

@ -1361,10 +1361,26 @@ static inline void dec_mm_counter(struct mm_struct *mm, int member)
atomic_long_dec(&mm->rss_stat.count[member]);
}
/* Optimized variant when page is already known not to be PageAnon */
static inline int mm_counter_file(struct page *page)
{
if (PageSwapBacked(page))
return MM_SHMEMPAGES;
return MM_FILEPAGES;
}
static inline int mm_counter(struct page *page)
{
if (PageAnon(page))
return MM_ANONPAGES;
return mm_counter_file(page);
}
static inline unsigned long get_mm_rss(struct mm_struct *mm)
{
return get_mm_counter(mm, MM_FILEPAGES) +
get_mm_counter(mm, MM_ANONPAGES);
get_mm_counter(mm, MM_ANONPAGES) +
get_mm_counter(mm, MM_SHMEMPAGES);
}
static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)

View file

@ -369,9 +369,10 @@ struct core_state {
};
enum {
MM_FILEPAGES,
MM_ANONPAGES,
MM_SWAPENTS,
MM_FILEPAGES, /* Resident file mapping pages */
MM_ANONPAGES, /* Resident anonymous pages */
MM_SWAPENTS, /* Anonymous swap entries */
MM_SHMEMPAGES, /* Resident shared memory pages */
NR_MM_COUNTERS
};

View file

@ -180,7 +180,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
lru_cache_add_active_or_unevictable(kpage, vma);
if (!PageAnon(page)) {
dec_mm_counter(mm, MM_FILEPAGES);
dec_mm_counter(mm, mm_counter_file(page));
inc_mm_counter(mm, MM_ANONPAGES);
}

View file

@ -832,10 +832,7 @@ copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
} else if (is_migration_entry(entry)) {
page = migration_entry_to_page(entry);
if (PageAnon(page))
rss[MM_ANONPAGES]++;
else
rss[MM_FILEPAGES]++;
rss[mm_counter(page)]++;
if (is_write_migration_entry(entry) &&
is_cow_mapping(vm_flags)) {
@ -874,10 +871,7 @@ copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
if (page) {
get_page(page);
page_dup_rmap(page);
if (PageAnon(page))
rss[MM_ANONPAGES]++;
else
rss[MM_FILEPAGES]++;
rss[mm_counter(page)]++;
}
out_set_pte:
@ -1113,9 +1107,8 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
tlb_remove_tlb_entry(tlb, pte, addr);
if (unlikely(!page))
continue;
if (PageAnon(page))
rss[MM_ANONPAGES]--;
else {
if (!PageAnon(page)) {
if (pte_dirty(ptent)) {
force_flush = 1;
set_page_dirty(page);
@ -1123,8 +1116,8 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
if (pte_young(ptent) &&
likely(!(vma->vm_flags & VM_SEQ_READ)))
mark_page_accessed(page);
rss[MM_FILEPAGES]--;
}
rss[mm_counter(page)]--;
page_remove_rmap(page);
if (unlikely(page_mapcount(page) < 0))
print_bad_pte(vma, addr, ptent, page);
@ -1146,11 +1139,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
struct page *page;
page = migration_entry_to_page(entry);
if (PageAnon(page))
rss[MM_ANONPAGES]--;
else
rss[MM_FILEPAGES]--;
rss[mm_counter(page)]--;
}
if (unlikely(!free_swap_and_cache(entry)))
print_bad_pte(vma, addr, ptent, NULL);
@ -1460,7 +1449,7 @@ static int insert_page(struct vm_area_struct *vma, unsigned long addr,
/* Ok, finally just insert the thing.. */
get_page(page);
inc_mm_counter_fast(mm, MM_FILEPAGES);
inc_mm_counter_fast(mm, mm_counter_file(page));
page_add_file_rmap(page);
set_pte_at(mm, addr, pte, mk_pte(page, prot));
@ -2097,7 +2086,8 @@ static int wp_page_copy(struct mm_struct *mm, struct vm_area_struct *vma,
if (likely(pte_same(*page_table, orig_pte))) {
if (old_page) {
if (!PageAnon(old_page)) {
dec_mm_counter_fast(mm, MM_FILEPAGES);
dec_mm_counter_fast(mm,
mm_counter_file(old_page));
inc_mm_counter_fast(mm, MM_ANONPAGES);
}
} else {
@ -2820,7 +2810,7 @@ void do_set_pte(struct vm_area_struct *vma, unsigned long address,
inc_mm_counter_fast(vma->vm_mm, MM_ANONPAGES);
page_add_new_anon_rmap(page, vma, address);
} else {
inc_mm_counter_fast(vma->vm_mm, MM_FILEPAGES);
inc_mm_counter_fast(vma->vm_mm, mm_counter_file(page));
page_add_file_rmap(page);
}
set_pte_at(vma->vm_mm, address, pte, entry);

View file

@ -585,10 +585,11 @@ void oom_kill_process(struct oom_control *oc, struct task_struct *p,
*/
do_send_sig_info(SIGKILL, SEND_SIG_FORCED, victim, true);
mark_oom_victim(victim);
pr_err("Killed process %d (%s) total-vm:%lukB, anon-rss:%lukB, file-rss:%lukB\n",
pr_err("Killed process %d (%s) total-vm:%lukB, anon-rss:%lukB, file-rss:%lukB, shmem-rss:%lukB\n",
task_pid_nr(victim), victim->comm, K(victim->mm->total_vm),
K(get_mm_counter(victim->mm, MM_ANONPAGES)),
K(get_mm_counter(victim->mm, MM_FILEPAGES)));
K(get_mm_counter(victim->mm, MM_FILEPAGES)),
K(get_mm_counter(victim->mm, MM_SHMEMPAGES)));
task_unlock(victim);
/*

View file

@ -1364,10 +1364,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
if (PageHuge(page)) {
hugetlb_count_sub(1 << compound_order(page), mm);
} else {
if (PageAnon(page))
dec_mm_counter(mm, MM_ANONPAGES);
else
dec_mm_counter(mm, MM_FILEPAGES);
dec_mm_counter(mm, mm_counter(page));
}
set_pte_at(mm, address, pte,
swp_entry_to_pte(make_hwpoison_entry(page)));
@ -1377,10 +1374,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
* interest anymore. Simply discard the pte, vmscan
* will take care of the rest.
*/
if (PageAnon(page))
dec_mm_counter(mm, MM_ANONPAGES);
else
dec_mm_counter(mm, MM_FILEPAGES);
dec_mm_counter(mm, mm_counter(page));
} else if (IS_ENABLED(CONFIG_MIGRATION) && (flags & TTU_MIGRATION)) {
swp_entry_t entry;
pte_t swp_pte;
@ -1420,7 +1414,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
swp_pte = pte_swp_mksoft_dirty(swp_pte);
set_pte_at(mm, address, pte, swp_pte);
} else
dec_mm_counter(mm, MM_FILEPAGES);
dec_mm_counter(mm, mm_counter_file(page));
page_remove_rmap(page);
page_cache_release(page);