Since we allocate a temporary buffer in zram_bvec_read to handle partial page
operations in this commit 924bd88d703e53d30f393fac6117f8f1bc79aab6 (Staging:
zram: allow partial page operations), our ->failed_reads value may be incorrect
as we do not increase its value when failed to allocate the temporary buffer.
Let's fix this issue and correct the annotation of failed_reads.
v2: clean codes of failed_{reads,writes} stat pointed out by Minchan Kim, and
this cleanup also fix incorrectly stat when fail in zram_decompress_page.
Signed-off-by: Chao Yu <chao2...@samsung.com>
---
drivers/block/zram/zram_drv.c | 10 +++++++---
drivers/block/zram/zram_drv.h | 2 +-
2 files changed, 8 insertions(+), 4 deletions(-)
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index dfa4024..d00831c 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -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 @@ out:
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;
}
diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h
index 5b0afde..e0f725c 100644
--- a/drivers/block/zram/zram_drv.h
+++ b/drivers/block/zram/zram_drv.h
@@ -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 */
--
2.0.1.474.g72c7794
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
