Commit 9b353db1 authored by Minchan Kim's avatar Minchan Kim Committed by Linus Torvalds

zram: delay pending free request in read path

Sergey reported we don't need to handle pending free request every I/O
so that this patch removes it in read path while we remain it in write
path.

Let's consider below example.

Swap subsystem ask to zram "A" block free by swap_slot_free_notify but
zram had been pended it without real freeing.  Swap subsystem allocates
"A" block for new data but request pended for a long time just handled
and zram blindly free new data on the "A" block.  :(

That's why we couldn't remove handle pending free request right before
zram-write.
Signed-off-by: default avatarMinchan Kim <minchan@kernel.org>
Reported-by: default avatarSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Tested-by: default avatarSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent da4a0412
...@@ -535,7 +535,6 @@ static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index, ...@@ -535,7 +535,6 @@ static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index,
if (rw == READ) { if (rw == READ) {
down_read(&zram->lock); down_read(&zram->lock);
handle_pending_slot_free(zram);
ret = zram_bvec_read(zram, bvec, index, offset, bio); ret = zram_bvec_read(zram, bvec, index, offset, bio);
up_read(&zram->lock); up_read(&zram->lock);
} else { } else {
......
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