mm: add per-order mTHP split counters

Patch series "mm: introduce per-order mTHP split counters", v3.

At present, the split counters in THP statistics no longer include
PTE-mapped mTHP.  Therefore, we want to introduce per-order mTHP split
counters to monitor the frequency of mTHP splits.  This will assist
developers in better analyzing and optimizing system performance.

/sys/kernel/mm/transparent_hugepage/hugepages-<size>/stats
        split
        split_failed
        split_deferred


This patch (of 2):

Currently, the split counters in THP statistics no longer include
PTE-mapped mTHP.  Therefore, we propose introducing per-order mTHP split
counters to monitor the frequency of mTHP splits.  This will help
developers better analyze and optimize system performance.

/sys/kernel/mm/transparent_hugepage/hugepages-<size>/stats
        split
        split_failed
        split_deferred

[ioworker0@gmail.com: make things more readable, per Barry and Baolin]
  Link: https://lkml.kernel.org/r/20240704012905.42971-2-ioworker0@gmail.com
[ioworker0@gmail.com: use == for `order' test, per David]
  Link: https://lkml.kernel.org/r/20240705113119.82210-1-ioworker0@gmail.com
Link: https://lkml.kernel.org/r/20240704012905.42971-1-ioworker0@gmail.com
Link: https://lkml.kernel.org/r/20240704012905.42971-2-ioworker0@gmail.com
Link: https://lkml.kernel.org/r/20240628130750.73097-1-ioworker0@gmail.com
Link: https://lkml.kernel.org/r/20240628130750.73097-2-ioworker0@gmail.com
Signed-off-by: Mingzhe Yang <mingzhe.yang@ly.com>
Signed-off-by: Lance Yang <ioworker0@gmail.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: Barry Song <baohua@kernel.org>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Bang Li <libang.li@antgroup.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Lance Yang 2024-06-28 21:07:49 +08:00 committed by Andrew Morton
parent d468f1b8cb
commit f216c845f3
2 changed files with 13 additions and 2 deletions

View File

@ -284,6 +284,9 @@ enum mthp_stat_item {
MTHP_STAT_FILE_ALLOC,
MTHP_STAT_FILE_FALLBACK,
MTHP_STAT_FILE_FALLBACK_CHARGE,
MTHP_STAT_SPLIT,
MTHP_STAT_SPLIT_FAILED,
MTHP_STAT_SPLIT_DEFERRED,
__MTHP_STAT_COUNT
};

View File

@ -559,6 +559,9 @@ DEFINE_MTHP_STAT_ATTR(swpout_fallback, MTHP_STAT_SWPOUT_FALLBACK);
DEFINE_MTHP_STAT_ATTR(file_alloc, MTHP_STAT_FILE_ALLOC);
DEFINE_MTHP_STAT_ATTR(file_fallback, MTHP_STAT_FILE_FALLBACK);
DEFINE_MTHP_STAT_ATTR(file_fallback_charge, MTHP_STAT_FILE_FALLBACK_CHARGE);
DEFINE_MTHP_STAT_ATTR(split, MTHP_STAT_SPLIT);
DEFINE_MTHP_STAT_ATTR(split_failed, MTHP_STAT_SPLIT_FAILED);
DEFINE_MTHP_STAT_ATTR(split_deferred, MTHP_STAT_SPLIT_DEFERRED);
static struct attribute *stats_attrs[] = {
&anon_fault_alloc_attr.attr,
@ -569,6 +572,9 @@ static struct attribute *stats_attrs[] = {
&file_alloc_attr.attr,
&file_fallback_attr.attr,
&file_fallback_charge_attr.attr,
&split_attr.attr,
&split_failed_attr.attr,
&split_deferred_attr.attr,
NULL,
};
@ -3068,7 +3074,7 @@ int split_huge_page_to_list_to_order(struct page *page, struct list_head *list,
XA_STATE_ORDER(xas, &folio->mapping->i_pages, folio->index, new_order);
struct anon_vma *anon_vma = NULL;
struct address_space *mapping = NULL;
bool is_thp = folio_test_pmd_mappable(folio);
int order = folio_order(folio);
int extra_pins, ret;
pgoff_t end;
bool is_hzp;
@ -3253,8 +3259,9 @@ out_unlock:
i_mmap_unlock_read(mapping);
out:
xas_destroy(&xas);
if (is_thp)
if (order == HPAGE_PMD_ORDER)
count_vm_event(!ret ? THP_SPLIT_PAGE : THP_SPLIT_PAGE_FAILED);
count_mthp_stat(order, !ret ? MTHP_STAT_SPLIT : MTHP_STAT_SPLIT_FAILED);
return ret;
}
@ -3307,6 +3314,7 @@ void deferred_split_folio(struct folio *folio)
if (list_empty(&folio->_deferred_list)) {
if (folio_test_pmd_mappable(folio))
count_vm_event(THP_DEFERRED_SPLIT_PAGE);
count_mthp_stat(folio_order(folio), MTHP_STAT_SPLIT_DEFERRED);
list_add_tail(&folio->_deferred_list, &ds_queue->split_queue);
ds_queue->split_queue_len++;
#ifdef CONFIG_MEMCG