Commit 02347792 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Andrew Morton
Browse files

khugepaged: remove hpage from collapse_huge_page() 

Work purely in terms of the folio.  Removes a call to compound_head()
in put_page().

Link: https://lkml.kernel.org/r/20240403171838.1445826-4-willy@infradead.org


Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: default avatarVishal Moola (Oracle) <vishal.moola@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent d5ab50b9

mm/khugepaged.c

+5 −7
Original line number Diff line number Diff line
@@ -1082,7 +1082,6 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address, 
	pte_t *pte;

	pgtable_t pgtable;

	struct folio *folio;

	struct page *hpage;

	spinlock_t *pmd_ptl, *pte_ptl;

	int result = SCAN_FAIL;

	struct vm_area_struct *vma;
@@ -1099,7 +1098,6 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address, 
	mmap_read_unlock(mm);



	result = alloc_charge_folio(&folio, mm, cc);

	hpage = &folio->page;

	if (result != SCAN_SUCCEED)

		goto out_nolock;
@@ -1198,7 +1196,7 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address, 
	 */

	anon_vma_unlock_write(vma->anon_vma);



	result = __collapse_huge_page_copy(pte, hpage, pmd, _pmd,

	result = __collapse_huge_page_copy(pte, &folio->page, pmd, _pmd,

					   vma, address, pte_ptl,

					   &compound_pagelist);

	pte_unmap(pte);
@@ -1213,7 +1211,7 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address, 
	__folio_mark_uptodate(folio);

	pgtable = pmd_pgtable(_pmd);



	_pmd = mk_huge_pmd(hpage, vma->vm_page_prot);

	_pmd = mk_huge_pmd(&folio->page, vma->vm_page_prot);

	_pmd = maybe_pmd_mkwrite(pmd_mkdirty(_pmd), vma);



	spin_lock(pmd_ptl);
@@ -1225,14 +1223,14 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address, 
	update_mmu_cache_pmd(vma, address, pmd);

	spin_unlock(pmd_ptl);



	hpage = NULL;

	folio = NULL;



	result = SCAN_SUCCEED;

out_up_write:

	mmap_write_unlock(mm);

out_nolock:

	if (hpage)

		put_page(hpage);

	if (folio)

		folio_put(folio);

	trace_mm_collapse_huge_page(mm, result == SCAN_SUCCEED, result);

	return result;

}