f2fs: introduce mempool for {,de}compress intermediate page allocation
If compression feature is on, in scenario of no enough free memory,
page refault ratio is higher than before, the root cause is:
- {,de}compression flow needs to allocate intermediate pages to store
compressed data in cluster, so during their allocation, vm may reclaim
mmaped pages.
- if above reclaimed pages belong to compressed cluster, during its
refault, it may cause more intermediate pages allocation, result in
reclaiming more mmaped pages.
So this patch introduces a mempool for intermediate page allocation,
in order to avoid high refault ratio, by default, number of
preallocated page in pool is 512, user can change the number by
assigning 'num_compress_pages' parameter during module initialization.
Ma Feng found warnings in the original patch and fixed like below.
Fix the following sparse warning:
fs/f2fs/compress.c:501:5: warning: symbol 'num_compress_pages' was not declared.
Should it be static?
fs/f2fs/compress.c:530:6: warning: symbol 'f2fs_compress_free_page' was not
declared. Should it be static?
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Ma Feng <mafeng.ma@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index d0a705e..1b170fc 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -3879,7 +3879,12 @@ static int __init init_f2fs_fs(void)
err = f2fs_init_bioset();
if (err)
goto free_bio_enrty_cache;
+ err = f2fs_init_compress_mempool();
+ if (err)
+ goto free_bioset;
return 0;
+free_bioset:
+ f2fs_destroy_bioset();
free_bio_enrty_cache:
f2fs_destroy_bio_entry_cache();
free_post_read:
@@ -3907,6 +3912,7 @@ static int __init init_f2fs_fs(void)
static void __exit exit_f2fs_fs(void)
{
+ f2fs_destroy_compress_mempool();
f2fs_destroy_bioset();
f2fs_destroy_bio_entry_cache();
f2fs_destroy_post_read_processing();