The patch titled
Subject: mm/filemap: don't relock the page after calling readpage
has been added to the -mm tree. Its filename is
mm-filemap-dont-relock-the-page-after-calling-readpage.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-filemap-dont-relock-the-page-after-calling-readpage.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-filemap-dont-relock-the-page-after-calling-readpage.patch
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm/filemap: don't relock the page after calling readpage
We don't need to get the page lock again; we just need to wait for the I/O
to finish, so use wait_on_page_locked_killable() like the other callers of
->readpage.
Link: https://lkml.kernel.org/r/20210122160140.223228-17-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/filemap.c | 21 +++++++--------------
1 file changed, 7 insertions(+), 14 deletions(-)
--- a/mm/filemap.c~mm-filemap-dont-relock-the-page-after-calling-readpage
+++ a/mm/filemap.c
@@ -2208,23 +2208,16 @@ static int filemap_read_page(struct file
error = mapping->a_ops->readpage(file, page);
if (error)
return error;
- if (PageUptodate(page))
- return 0;
- error = lock_page_killable(page);
+ error = wait_on_page_locked_killable(page);
if (error)
return error;
- if (!PageUptodate(page)) {
- if (page->mapping == NULL) {
- /* page truncated */
- error = AOP_TRUNCATED_PAGE;
- } else {
- shrink_readahead_size_eio(&file->f_ra);
- error = -EIO;
- }
- }
- unlock_page(page);
- return error;
+ if (PageUptodate(page))
+ return 0;
+ if (!page->mapping) /* page truncated */
+ return AOP_TRUNCATED_PAGE;
+ shrink_readahead_size_eio(&file->f_ra);
+ return -EIO;
}
static bool filemap_range_uptodate(struct address_space *mapping,
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-debug-improve-memcg-debugging.patch
mm-filemap-rename-generic_file_buffered_read-subfunctions.patch
mm-filemap-remove-dynamically-allocated-array-from-filemap_read.patch
mm-filemap-convert-filemap_get_pages-to-take-a-pagevec.patch
mm-filemap-use-head-pages-in-generic_file_buffered_read.patch
mm-filemap-pass-a-sleep-state-to-put_and_wait_on_page_locked.patch
mm-filemap-support-readpage-splitting-a-page.patch
mm-filemap-inline-__wait_on_page_locked_async-into-caller.patch
mm-filemap-dont-call-readpage-if-iocb_waitq-is-set.patch
mm-filemap-change-filemap_read_page-calling-conventions.patch
mm-filemap-change-filemap_create_page-calling-conventions.patch
mm-filemap-convert-filemap_update_page-to-return-an-errno.patch
mm-filemap-move-the-iocb-checks-into-filemap_update_page.patch
mm-filemap-add-filemap_range_uptodate.patch
mm-filemap-split-filemap_readahead-out-of-filemap_get_pages.patch
mm-filemap-restructure-filemap_get_pages.patch
mm-filemap-dont-relock-the-page-after-calling-readpage.patch
mm-make-pagecache-tagged-lookups-return-only-head-pages.patch
mm-shmem-use-pagevec_lookup-in-shmem_unlock_mapping.patch
mm-swap-optimise-get_shadow_from_swap_cache.patch
mm-add-fgp_entry.patch
mm-filemap-rename-find_get_entry-to-mapping_get_entry.patch
mm-filemap-add-helper-for-finding-pages.patch
mm-filemap-add-helper-for-finding-pages-fix.patch
mm-filemap-add-mapping_seek_hole_data.patch
mm-filemap-add-mapping_seek_hole_data-fix.patch
iomap-use-mapping_seek_hole_data.patch
mm-add-and-use-find_lock_entries.patch
mm-add-and-use-find_lock_entries-fix.patch
mm-add-an-end-parameter-to-find_get_entries.patch
mm-add-an-end-parameter-to-pagevec_lookup_entries.patch
mm-remove-nr_entries-parameter-from-pagevec_lookup_entries.patch
mm-pass-pvec-directly-to-find_get_entries.patch
mm-remove-pagevec_lookup_entries.patch
