The patch titled
Subject: mm: report success more often from filemap_map_folio_range()
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-report-success-more-often-from-filemap_map_folio_range.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-report-success-more-often-from-filemap_map_folio_range.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm: report success more often from filemap_map_folio_range()
Date: Wed, 20 Sep 2023 04:53:35 +0100
Even though we had successfully mapped the relevant page, we would rarely
return success from filemap_map_folio_range(). That leads to falling back
from the VMA lock path to the mmap_lock path, which is a speed &
scalability issue. Found by inspection.
Link: https://lkml.kernel.org/r/20230920035336.854212-1-willy@xxxxxxxxxxxxx
Fixes: 617c28ecab22 ("filemap: batch PTE mappings")
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Yin Fengwei <fengwei.yin@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/filemap.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/mm/filemap.c~mm-report-success-more-often-from-filemap_map_folio_range
+++ a/mm/filemap.c
@@ -3503,7 +3503,7 @@ skip:
if (count) {
set_pte_range(vmf, folio, page, count, addr);
folio_ref_add(folio, count);
- if (in_range(vmf->address, addr, count))
+ if (in_range(vmf->address, addr, count * PAGE_SIZE))
ret = VM_FAULT_NOPAGE;
}
@@ -3517,7 +3517,7 @@ skip:
if (count) {
set_pte_range(vmf, folio, page, count, addr);
folio_ref_add(folio, count);
- if (in_range(vmf->address, addr, count))
+ if (in_range(vmf->address, addr, count * PAGE_SIZE))
ret = VM_FAULT_NOPAGE;
}
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
i915-limit-the-length-of-an-sg-list-to-the-requested-length.patch
mm-report-success-more-often-from-filemap_map_folio_range.patch
mm-abstract-moving-to-the-next-pfn.patch
mm-convert-dax-lock-unlock-page-to-lock-unlock-folio.patch
buffer-pass-gfp-flags-to-folio_alloc_buffers.patch
buffer-hoist-gfp-flags-from-grow_dev_page-to-__getblk_gfp.patch
ext4-use-bdev_getblk-to-avoid-memory-reclaim-in-readahead-path.patch
buffer-use-bdev_getblk-to-avoid-memory-reclaim-in-readahead-path.patch
buffer-convert-getblk_unmovable-and-__getblk-to-use-bdev_getblk.patch
buffer-convert-sb_getblk-to-call-__getblk.patch
ext4-call-bdev_getblk-from-sb_getblk_gfp.patch
buffer-remove-__getblk_gfp.patch
hugetlb-use-a-folio-in-free_hpage_workfn.patch
hugetlb-remove-a-few-calls-to-page_folio.patch
hugetlb-convert-remove_pool_huge_page-to-remove_pool_hugetlb_folio.patch
