linux-toradex.git/mm/truncate.c, branch v5.12-rc8

mm: remove pagevec_lookup_entries

2021-02-26T17:40:59+00:00

pagevec_lookup_entries() is now just a wrapper around find_get_entries()
so remove it and convert all its callers.

Link: https://lkml.kernel.org/r/20201112212641.27837-15-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Jan Kara 
Reviewed-by: William Kucharski 
Reviewed-by: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Hugh Dickins 
Cc: Johannes Weiner 
Cc: Kirill A. Shutemov 
Cc: Yang Shi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: remove nr_entries parameter from pagevec_lookup_entries

2021-02-26T17:40:59+00:00

All callers want to fetch the full size of the pvec.

Link: https://lkml.kernel.org/r/20201112212641.27837-13-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Jan Kara 
Reviewed-by: William Kucharski 
Reviewed-by: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Hugh Dickins 
Cc: Johannes Weiner 
Cc: Kirill A. Shutemov 
Cc: Yang Shi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: add an 'end' parameter to pagevec_lookup_entries

2021-02-26T17:40:59+00:00

Simplifies the callers and uses the existing functionality in
find_get_entries().  We can also drop the final argument of
truncate_exceptional_pvec_entries() and simplify the logic in that
function.

Link: https://lkml.kernel.org/r/20201112212641.27837-12-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Jan Kara 
Reviewed-by: William Kucharski 
Reviewed-by: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Hugh Dickins 
Cc: Johannes Weiner 
Cc: Kirill A. Shutemov 
Cc: Yang Shi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: add and use find_lock_entries

2021-02-26T17:40:59+00:00

We have three functions (shmem_undo_range(), truncate_inode_pages_range()
and invalidate_mapping_pages()) which want exactly this function, so add
it to filemap.c.  Before this patch, shmem_undo_range() would split any
compound page which overlaps either end of the range being punched in both
the first and second loops through the address space.  After this patch,
that functionality is left for the second loop, which is arguably more
appropriate since the first loop is supposed to run through all the pages
quickly, and splitting a page can sleep.

[willy@infradead.org: add assertion]
  Link: https://lkml.kernel.org/r/20201124041507.28996-3-willy@infradead.org

Link: https://lkml.kernel.org/r/20201112212641.27837-10-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Jan Kara 
Reviewed-by: William Kucharski 
Reviewed-by: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Hugh Dickins 
Cc: Johannes Weiner 
Cc: Kirill A. Shutemov 
Cc: Yang Shi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: fix kernel-doc markups

2020-12-15T20:13:47+00:00

Kernel-doc markups should use this format:
        identifier - description

Fix some issues on mm files:

1) The definition for get_user_pages_locked() doesn't follow it.  Also,
   it expects a short descrpition at the header, followed by a long one,
   after the parameters.  Fix it.

2) Kernel-doc requires that a kernel-doc markup to be immediately below
   the function prototype, as otherwise it will rename it.  So, move
   get_pfnblock_flags_mask() description to the right place.

3) Make invalidate_mapping_pagevec() to also follow the expected
   kernel-doc format.

While here, fix a few minor English syntax issues, as suggested
by Matthew:
	will used -> will be used
	similar with -> similar to

Link: https://lkml.kernel.org/r/80e85dddc92d333bc2159ee8a2294921612e8745.1605521731.git.mchehab+huawei@kernel.org
Signed-off-by: Mauro Carvalho Chehab 
Suggested-by: Mattew Wilcox 	[English fixes]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/truncate: add parameter explanation for invalidate_mapping_pagevec

2020-12-15T20:13:38+00:00

To fix a kernel-doc markups issue:

  mm/truncate.c:646: warning: Function parameter or member 'mapping' not described in 'invalidate_mapping_pagevec'
  mm/truncate.c:646: warning: Function parameter or member 'start' not described in 'invalidate_mapping_pagevec'
  mm/truncate.c:646: warning: Function parameter or member 'end' not described in 'invalidate_mapping_pagevec'
  mm/truncate.c:646: warning: Function parameter or member 'nr_pagevec' not described in 'invalidate_mapping_pagevec'

Link: https://lkml.kernel.org/r/1605605088-30668-1-git-send-email-alex.shi@linux.alibaba.com
Signed-off-by: Alex Shi 
Cc: Jonathan Corbet 
Cc: Randy Dunlap 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/truncate.c: make __invalidate_mapping_pages() static

2020-11-02T20:14:19+00:00

Fix the following sparse warning:

  mm/truncate.c:531:15: warning: symbol '__invalidate_mapping_pages' was not declared. Should it be static?

Fixes: eb1d7a65f08a ("mm, fadvise: improve the expensive remote LRU cache draining after FADV_DONTNEED")
Signed-off-by: Jason Yan 
Signed-off-by: Andrew Morton 
Reviewed-by: Yafang Shao 
Link: https://lkml.kernel.org/r/20201015054808.2445904-1-yanaijie@huawei.com
Signed-off-by: Linus Torvalds

mm/truncate: fix truncation for pages of arbitrary size

2020-10-16T18:11:15+00:00

Remove the assumption that a compound page is HPAGE_PMD_SIZE, and the
assumption that any page is PAGE_SIZE.

Signed-off-by: Matthew Wilcox (Oracle) 
Signed-off-by: Andrew Morton 
Reviewed-by: SeongJae Park 
Acked-by: Kirill A. Shutemov 
Cc: Huang Ying 
Link: https://lkml.kernel.org/r/20200908195539.25896-10-willy@infradead.org
Signed-off-by: Linus Torvalds

mm, fadvise: improve the expensive remote LRU cache draining after FADV_DONTNEED

2020-10-14T01:38:29+00:00

Our users reported that there're some random latency spikes when their RT
process is running.  Finally we found that latency spike is caused by
FADV_DONTNEED.  Which may call lru_add_drain_all() to drain LRU cache on
remote CPUs, and then waits the per-cpu work to complete.  The wait time
is uncertain, which may be tens millisecond.

That behavior is unreasonable, because this process is bound to a specific
CPU and the file is only accessed by itself, IOW, there should be no
pagecache pages on a per-cpu pagevec of a remote CPU.  That unreasonable
behavior is partially caused by the wrong comparation of the number of
invalidated pages and the number of the target.  For example,

        if (count < (end_index - start_index + 1))

The count above is how many pages were invalidated in the local CPU, and
(end_index - start_index + 1) is how many pages should be invalidated.
The usage of (end_index - start_index + 1) is incorrect, because they are
virtual addresses, which may not mapped to pages.  Besides that, there may
be holes between start and end.  So we'd better check whether there are
still pages on per-cpu pagevec after drain the local cpu, and then decide
whether or not to call lru_add_drain_all().

After I applied it with a hotfix to our production environment, most of
the lru_add_drain_all() can be avoided.

Suggested-by: Mel Gorman 
Signed-off-by: Yafang Shao 
Signed-off-by: Andrew Morton 
Acked-by: Mel Gorman 
Cc: Johannes Weiner 
Link: https://lkml.kernel.org/r/20200923133318.14373-1-laoar.shao@gmail.com
Signed-off-by: Linus Torvalds

mm/thp: allow dropping THP from page cache

2019-10-19T10:32:33+00:00

Once a THP is added to the page cache, it cannot be dropped via
/proc/sys/vm/drop_caches.  Fix this issue with proper handling in
invalidate_mapping_pages().

Link: http://lkml.kernel.org/r/20191017164223.2762148-5-songliubraving@fb.com
Fixes: 99cb0dbd47a1 ("mm,thp: add read-only THP support for (non-shmem) FS")
Signed-off-by: Kirill A. Shutemov 
Signed-off-by: Song Liu 
Tested-by: Song Liu 
Acked-by: Yang Shi 
Cc: Matthew Wilcox (Oracle) 
Cc: Oleg Nesterov 
Cc: Srikar Dronamraju 
Cc: William Kucharski 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds