Commit 5fcd079a authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Andrew Morton
Browse files

uprobes: use folios more widely in __replace_page() 

Remove a few hidden calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-45-willy@infradead.org


Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 98b211d6

kernel/events/uprobes.c

+10 −9
Original line number Diff line number Diff line
@@ -19,7 +19,7 @@ 
#include <linux/export.h>

#include <linux/rmap.h>		/* anon_vma_prepare */

#include <linux/mmu_notifier.h>	/* set_pte_at_notify */

#include <linux/swap.h>		/* try_to_free_swap */

#include <linux/swap.h>		/* folio_free_swap */

#include <linux/ptrace.h>	/* user_enable_single_step */

#include <linux/kdebug.h>	/* notifier mechanism */

#include "../../mm/internal.h"	/* munlock_vma_page */
@@ -154,8 +154,9 @@ static loff_t vaddr_to_offset(struct vm_area_struct *vma, unsigned long vaddr) 
static int __replace_page(struct vm_area_struct *vma, unsigned long addr,

				struct page *old_page, struct page *new_page)

{

	struct folio *old_folio = page_folio(old_page);

	struct mm_struct *mm = vma->vm_mm;

	DEFINE_FOLIO_VMA_WALK(pvmw, page_folio(old_page), vma, addr, 0);

	DEFINE_FOLIO_VMA_WALK(pvmw, old_folio, vma, addr, 0);

	int err;

	struct mmu_notifier_range range;
@@ -169,8 +170,8 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, 
			return err;

	}



	/* For try_to_free_swap() below */

	lock_page(old_page);

	/* For folio_free_swap() below */

	folio_lock(old_folio);



	mmu_notifier_invalidate_range_start(&range);

	err = -EAGAIN;
@@ -186,7 +187,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, 
		/* no new page, just dec_mm_counter for old_page */

		dec_mm_counter(mm, MM_ANONPAGES);



	if (!PageAnon(old_page)) {

	if (!folio_test_anon(old_folio)) {

		dec_mm_counter(mm, mm_counter_file(old_page));

		inc_mm_counter(mm, MM_ANONPAGES);

	}
@@ -198,15 +199,15 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, 
				  mk_pte(new_page, vma->vm_page_prot));



	page_remove_rmap(old_page, vma, false);

	if (!page_mapped(old_page))

		try_to_free_swap(old_page);

	if (!folio_mapped(old_folio))

		folio_free_swap(old_folio);

	page_vma_mapped_walk_done(&pvmw);

	put_page(old_page);

	folio_put(old_folio);



	err = 0;

 unlock:

	mmu_notifier_invalidate_range_end(&range);

	unlock_page(old_page);

	folio_unlock(old_folio);

	return err;

}