diff options
| author | Usama Arif <usamaarif642@gmail.com> | 2024-06-10 15:30:37 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-07-03 19:30:07 -0700 |
| commit | 9ba85f5529f1110aa6d787f8f12553a713f945fc (patch) | |
| tree | d2798113c9015c77196c39c9939ef9b8d0f81e1e /mm/page_io.c | |
| parent | ecc1793b2d08efeb2d1795814d2ea350c9d6992b (diff) | |
mm: do not start/end writeback for pages stored in zswap
Most of the work done in folio_start_writeback is reversed in
folio_end_writeback. For e.g. NR_WRITEBACK and NR_ZONE_WRITE_PENDING are
incremented in start_writeback and decremented in end_writeback. Calling
end_writeback immediately after start_writeback (separated by
folio_unlock) cancels the affect of most of the work done in start hence
can be removed.
There is some extra work done in folio_end_writeback, however it is
incorrect/not applicable to zswap:
- folio_end_writeback incorrectly increments NR_WRITTEN counter,
eventhough the pages aren't written to disk, hence this change
corrects this behaviour.
- folio_end_writeback calls folio_rotate_reclaimable, but that only
makes sense for async writeback pages, while for zswap pages are
synchronously reclaimed.
Link: https://lkml.kernel.org/r/20240612100109.1616626-1-usamaarif642@gmail.com
Link: https://lkml.kernel.org/r/20240610143037.812955-1-usamaarif642@gmail.com
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/page_io.c')
| -rw-r--r-- | mm/page_io.c | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/mm/page_io.c b/mm/page_io.c index f1a9cfab6e74..488ecacef84f 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -196,9 +196,7 @@ int swap_writepage(struct page *page, struct writeback_control *wbc) return ret; } if (zswap_store(folio)) { - folio_start_writeback(folio); folio_unlock(folio); - folio_end_writeback(folio); return 0; } if (!mem_cgroup_zswap_writeback_enabled(folio_memcg(folio))) { |