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mm/khugepaged: convert __collapse_huge_page_isolate() to use folios

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Patch series "Some khugepaged folio conversions", v3.

This patchset converts a number of functions to use folios.  This cleans
up some khugepaged code and removes a large number of hidden
compound_head() calls.


This patch (of 5):

Replaces 11 calls to compound_head() with 1, and removes 1348 bytes of
kernel text.

Link: https://lkml.kernel.org/r/20231020183331.10770-1-vishal.moola@gmail.com
Link: https://lkml.kernel.org/r/20231020183331.10770-2-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Vishal Moola (Oracle) 2023-10-20 11:33:27 -07:00 committed by Andrew Morton
parent b7812c86c7
commit 8dd1e89673
1 changed files with 23 additions and 22 deletions
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45
mm/khugepaged.c
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@ -542,6 +542,7 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
struct list_head *compound_pagelist)
{
struct page *page = NULL;
struct folio *folio = NULL;
pte_t *_pte;
int none_or_zero = 0, shared = 0, result = SCAN_FAIL, referenced = 0;
bool writable = false;
@ -576,7 +577,8 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
goto out;
}
VM_BUG_ON_PAGE(!PageAnon(page), page);
folio = page_folio(page);
VM_BUG_ON_FOLIO(!folio_test_anon(folio), folio);
if (page_mapcount(page) > 1) {
++shared;
@ -588,16 +590,15 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
}
}
if (PageCompound(page)) {
struct page *p;
page = compound_head(page);
if (folio_test_large(folio)) {
struct folio *f;
/*
* Check if we have dealt with the compound page
* already
*/
list_for_each_entry(p, compound_pagelist, lru) {
if (page == p)
list_for_each_entry(f, compound_pagelist, lru) {
if (folio == f)
goto next;
}
}
@ -608,7 +609,7 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
* is needed to serialize against split_huge_page
* when invoked from the VM.
*/
if (!trylock_page(page)) {
if (!folio_trylock(folio)) {
result = SCAN_PAGE_LOCK;
goto out;
}
@ -624,8 +625,8 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
* but not from this process. The other process cannot write to
* the page, only trigger CoW.
*/
if (!is_refcount_suitable(page)) {
unlock_page(page);
if (!is_refcount_suitable(&folio->page)) {
folio_unlock(folio);
result = SCAN_PAGE_COUNT;
goto out;
}
@ -634,27 +635,27 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
* Isolate the page to avoid collapsing an hugepage
* currently in use by the VM.
*/
if (!isolate_lru_page(page)) {
unlock_page(page);
if (!folio_isolate_lru(folio)) {
folio_unlock(folio);
result = SCAN_DEL_PAGE_LRU;
goto out;
}
mod_node_page_state(page_pgdat(page),
NR_ISOLATED_ANON + page_is_file_lru(page),
compound_nr(page));
VM_BUG_ON_PAGE(!PageLocked(page), page);
VM_BUG_ON_PAGE(PageLRU(page), page);
node_stat_mod_folio(folio,
NR_ISOLATED_ANON + folio_is_file_lru(folio),
folio_nr_pages(folio));
VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
VM_BUG_ON_FOLIO(folio_test_lru(folio), folio);
if (PageCompound(page))
list_add_tail(&page->lru, compound_pagelist);
if (folio_test_large(folio))
list_add_tail(&folio->lru, compound_pagelist);
next:
/*
* If collapse was initiated by khugepaged, check that there is
* enough young pte to justify collapsing the page
*/
if (cc->is_khugepaged &&
(pte_young(pteval) || page_is_young(page) ||
PageReferenced(page) || mmu_notifier_test_young(vma->vm_mm,
(pte_young(pteval) || folio_test_young(folio) ||
folio_test_referenced(folio) || mmu_notifier_test_young(vma->vm_mm,
address)))
referenced++;
@ -668,13 +669,13 @@ next:
result = SCAN_LACK_REFERENCED_PAGE;
} else {
result = SCAN_SUCCEED;
trace_mm_collapse_huge_page_isolate(page, none_or_zero,
trace_mm_collapse_huge_page_isolate(&folio->page, none_or_zero,
referenced, writable, result);
return result;
}
out:
release_pte_pages(pte, _pte, compound_pagelist);
trace_mm_collapse_huge_page_isolate(page, none_or_zero,
trace_mm_collapse_huge_page_isolate(&folio->page, none_or_zero,
referenced, writable, result);
return result;
}