zram: fix incorrect stat with failed_reads

Since we allocate a temporary buffer in zram_bvec_read to handle partial
page operations in commit 924bd88d70 ("Staging: zram: allow partial
page operations"), our ->failed_reads value may be incorrect as we do
not increase its value when failing to allocate the temporary buffer.

Let's fix this issue and correct the annotation of failed_reads.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Chao Yu 2014-08-29 15:18:37 -07:00 committed by Linus Torvalds
parent 0c38e1fe0f
commit 0cf1e9d6c3
2 changed files with 8 additions and 4 deletions

View file

@ -378,7 +378,6 @@ static int zram_decompress_page(struct zram *zram, char *mem, u32 index)
/* Should NEVER happen. Return bio error if it does. */
if (unlikely(ret)) {
pr_err("Decompression failed! err=%d, page=%u\n", ret, index);
atomic64_inc(&zram->stats.failed_reads);
return ret;
}
@ -547,8 +546,6 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
zcomp_strm_release(zram->comp, zstrm);
if (is_partial_io(bvec))
kfree(uncmem);
if (ret)
atomic64_inc(&zram->stats.failed_writes);
return ret;
}
@ -566,6 +563,13 @@ static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index,
ret = zram_bvec_write(zram, bvec, index, offset);
}
if (unlikely(ret)) {
if (rw == READ)
atomic64_inc(&zram->stats.failed_reads);
else
atomic64_inc(&zram->stats.failed_writes);
}
return ret;
}

View file

@ -84,7 +84,7 @@ struct zram_stats {
atomic64_t compr_data_size; /* compressed size of pages stored */
atomic64_t num_reads; /* failed + successful */
atomic64_t num_writes; /* --do-- */
atomic64_t failed_reads; /* should NEVER! happen */
atomic64_t failed_reads; /* can happen when memory is too low */
atomic64_t failed_writes; /* can happen when memory is too low */
atomic64_t invalid_io; /* non-page-aligned I/O requests */
atomic64_t notify_free; /* no. of swap slot free notifications */