Commit 7e9c56da authored by Lance Yang's avatar Lance Yang Committed by Liu Shixin
Browse files

mm: add per-order mTHP split counters 

mainline inclusion
from mainline-v6.11-rc1
commit f216c845f3c772e54d27fe209fd300b10e7bf54a
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/IAIHPC

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f216c845f3c772e54d27fe209fd300b10e7bf54a

--------------------------------

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: default avatarMingzhe Yang <mingzhe.yang@ly.com>
Signed-off-by: default avatarLance Yang <ioworker0@gmail.com>
Reviewed-by: default avatarRyan Roberts <ryan.roberts@arm.com>
Acked-by: default avatarBarry Song <baohua@kernel.org>
Reviewed-by: default avatarBaolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: default avatarDavid 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: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLiu Shixin <liushixin2@huawei.com>
parent e9c3ca09

include/linux/huge_mm.h

+3 −0
Original line number Diff line number Diff line
@@ -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

};

mm/huge_memory.c

+10 −2
Original line number Diff line number Diff line
@@ -722,6 +722,9 @@ 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,
@@ -732,6 +735,9 @@ 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,

};
@@ -3250,7 +3256,7 @@ 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;
@@ -3435,8 +3441,9 @@ int split_huge_page_to_list_to_order(struct page *page, struct list_head *list, 
		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;

}
@@ -3489,6 +3496,7 @@ 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