From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754224AbaHMCCn (ORCPT ); Tue, 12 Aug 2014 22:02:43 -0400 Received: from mailout2.samsung.com ([203.254.224.25]:18417 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752787AbaHMCCm (ORCPT ); Tue, 12 Aug 2014 22:02:42 -0400 X-AuditID: cbfee61a-f79e46d00000134f-8f-53eac73ee6dc From: Chao Yu To: minchan@kernel.org Cc: ngupta@vflare.org, linux-kernel@vger.kernel.org, "'Jerome Marchand'" , "'Sergey Senozhatsky'" , "'Andrew Morton'" Subject: [PATCH v2] zram: fix incorrectly stat with failed_reads Date: Wed, 13 Aug 2014 10:01:45 +0800 Message-id: <009001cfb69a$a8470840$f8d518c0$@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7bit X-Mailer: Microsoft Outlook 14.0 Thread-index: Ac+2lVbnDu0zflRtTGWlaMj1gTdWhg== Content-language: zh-cn X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrBLMWRmVeSWpSXmKPExsVy+t9jAV2746+CDW7/krKYs34Nm8WpP9eZ LC7vmsNmsezre3aLDS2z2C3Wfn7M7sDmsXPWXXaPTas62TxOzPjN4vF+31Wg2KfNrB6fN8kF sEVx2aSk5mSWpRbp2yVwZXw7wVKwT7ji9MGp7A2MfQJdjJwcEgImEtt/3WGCsMUkLtxbz9bF yMUhJLCIUWJ7wwVGCOcHo8T3WVcZQarYBFQklnf8B+sQAep4/OUHO0gRs8ARRomWv4fZQRLC Ag4SWw8uACtiEVCV6G6cAmbzClhKPPt1iA3CFpT4MfkeC4jNLKAlsX7ncSYIW15i85q3zBAn KUjsOPuaEWKZnsTy3kdQNeISG4/cYpnAKDALyahZSEbNQjJqFpKWBYwsqxhFUwuSC4qT0nMN 9YoTc4tL89L1kvNzNzGCw/+Z1A7GlQ0WhxgFOBiVeHgreF8FC7EmlhVX5h5ilOBgVhLhddgC FOJNSaysSi3Kjy8qzUktPsQozcGiJM57oNU6UEggPbEkNTs1tSC1CCbLxMEp1cCooivIHHX0 wVTriRP3fl/fcOgu665XF9+mOTcGeGarnXf+NCMwYyKvgUXTSqP5l71EXuzUP9bplrTWL+LI 5sv3Z0yYEBPy5cGqFT3rZx5c0nGJm7/6wiv5VRzilYdkp3JoZUxU96zJ/fy7/ZWcUplrU4c9 s+yq07qyOidXcj5Xy9j/MktmjvxMJZbijERDLeai4kQAbhWoH3sCAAA= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- 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