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author | Li Wang <liwang@redhat.com> | 2018-07-26 16:37:42 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-07-26 19:38:03 -0700 |
commit | 16e536ef47f567289a5699abee9ff7bb304bc12d (patch) | |
tree | 90e8f576c068c6f24dcda02dfc367b8eef0577d4 /fs/xfs/xfs_stats.h | |
parent | fa3fc2ad99b4f025446d1cff589a8d2dd7db92f2 (diff) | |
download | linux-16e536ef47f567289a5699abee9ff7bb304bc12d.tar.bz2 |
zswap: re-check zswap_is_full() after do zswap_shrink()
/sys/../zswap/stored_pages keeps rising in a zswap test with
"zswap.max_pool_percent=0" parameter. But it should not compress or
store pages any more since there is no space in the compressed pool.
Reproduce steps:
1. Boot kernel with "zswap.enabled=1"
2. Set the max_pool_percent to 0
# echo 0 > /sys/module/zswap/parameters/max_pool_percent
3. Do memory stress test to see if some pages have been compressed
# stress --vm 1 --vm-bytes $mem_available"M" --timeout 60s
4. Watching the 'stored_pages' number increasing or not
The root cause is:
When zswap_max_pool_percent is set to 0 via kernel parameter,
zswap_is_full() will always return true due to zswap_shrink(). But if
the shinking is able to reclain a page successfully the code then
proceeds to compressing/storing another page, so the value of
stored_pages will keep changing.
To solve the issue, this patch adds a zswap_is_full() check again after
zswap_shrink() to make sure it's now under the max_pool_percent, and to
not compress/store if we reached the limit.
Link: http://lkml.kernel.org/r/20180530103936.17812-1-liwang@redhat.com
Signed-off-by: Li Wang <liwang@redhat.com>
Acked-by: Dan Streetman <ddstreet@ieee.org>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Huang Ying <huang.ying.caritas@gmail.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/xfs/xfs_stats.h')
0 files changed, 0 insertions, 0 deletions