Commit 7b9b3094 authored by Kefeng Wang's avatar Kefeng Wang Committed by Peng Zhang
Browse files

mm: move mm counter updating out of set_pte_range() 

maillist inclusion
category: performance
bugzilla: https://gitee.com/openeuler/kernel/issues/I9GBVL
CVE: NA

Reference: https://lore.kernel.org/all/20240412064751.119015-2-wangkefeng.wang@huawei.com/



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

In order to support batch mm counter updating in filemap_map_pages(),
move mm counter updating out of set_pte_range(), the folios are file
from filemap, and distinguish folios by vmf->flags and vma->vm_flags
from another caller finish_fault().

Signed-off-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: default avatarZhangPeng <zhangpeng362@huawei.com>
parent 2ce949a8

mm/filemap.c

+4 −0
Original line number Diff line number Diff line
@@ -3500,6 +3500,8 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf, 
skip:

		if (count) {

			set_pte_range(vmf, folio, page, count, addr);

			add_mm_counter(vmf->vma->vm_mm, mm_counter_file(folio),

				       count);

			folio_ref_add(folio, count);

			if (in_range(vmf->address, addr, count * PAGE_SIZE))

				ret = VM_FAULT_NOPAGE;
@@ -3514,6 +3516,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf, 


	if (count) {

		set_pte_range(vmf, folio, page, count, addr);

		add_mm_counter(vmf->vma->vm_mm, mm_counter_file(folio), count);

		folio_ref_add(folio, count);

		if (in_range(vmf->address, addr, count * PAGE_SIZE))

			ret = VM_FAULT_NOPAGE;
@@ -3548,6 +3551,7 @@ static vm_fault_t filemap_map_order0_folio(struct vm_fault *vmf, 
		ret = VM_FAULT_NOPAGE;



	set_pte_range(vmf, folio, page, 1, addr);

	add_mm_counter(vmf->vma->vm_mm, mm_counter_file(folio), 1);

	folio_ref_inc(folio);



	return ret;

mm/memory.c

+5 −3
Original line number Diff line number Diff line
@@ -4660,12 +4660,10 @@ void set_pte_range(struct vm_fault *vmf, struct folio *folio, 
	/* copy-on-write page */

	add_reliable_folio_counter(folio, vma->vm_mm, nr);

	if (write && !(vma->vm_flags & VM_SHARED)) {

		add_mm_counter(vma->vm_mm, MM_ANONPAGES, nr);

		VM_BUG_ON_FOLIO(nr != 1, folio);

		folio_add_new_anon_rmap(folio, vma, addr);

		folio_add_lru_vma(folio, vma);

	} else {

		add_mm_counter(vma->vm_mm, mm_counter_file(folio), nr);

		folio_add_file_rmap_ptes(folio, page, nr, vma);

	}

	set_ptes(vma->vm_mm, addr, vmf->pte, entry, nr);
@@ -4702,9 +4700,11 @@ vm_fault_t finish_fault(struct vm_fault *vmf) 
	struct vm_area_struct *vma = vmf->vma;

	struct page *page;

	vm_fault_t ret;

	bool is_cow = (vmf->flags & FAULT_FLAG_WRITE) &&

		      !(vma->vm_flags & VM_SHARED);



	/* Did we COW the page? */

	if ((vmf->flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED))

	if (is_cow)

		page = vmf->cow_page;

	else

		page = vmf->page;
@@ -4740,8 +4740,10 @@ vm_fault_t finish_fault(struct vm_fault *vmf) 
	/* Re-check under ptl */

	if (likely(!vmf_pte_changed(vmf))) {

		struct folio *folio = page_folio(page);

		int type = is_cow ? MM_ANONPAGES : mm_counter_file(folio);



		set_pte_range(vmf, folio, page, 1, vmf->address);

		add_mm_counter(vma->vm_mm, type, 1);

		ret = 0;

	} else {

		update_mmu_tlb(vma, vmf->address, vmf->pte);