From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753984Ab1G0ANc (ORCPT ); Tue, 26 Jul 2011 20:13:32 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:62681 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751824Ab1G0ANa (ORCPT ); Tue, 26 Jul 2011 20:13:30 -0400 From: Wanlong Gao To: Vivek Goyal Cc: Wanlong Gao , Paul Menage , lizf@cn.fujitsu.com, axboe@kernel.dk, linux-kernel@vger.kernel.org, wanlong.gao@gmail.com Subject: [PATCH v5] blk-cgroup:be able to remove the record of unplugged device Date: Wed, 27 Jul 2011 08:11:48 +0800 Message-Id: <1311725508-4419-1-git-send-email-gaowanlong@cn.fujitsu.com> X-Mailer: git-send-email 1.7.6 In-Reply-To: <20110726192441.GD13780@redhat.com> References: <20110726192441.GD13780@redhat.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.1FP4|July 25, 2010) at 2011-07-27 08:12:29, Serialize by Router on mailserver/fnst(Release 8.5.1FP4|July 25, 2010) at 2011-07-27 08:12:29, Serialize complete at 2011-07-27 08:12:29 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The bug is we're not able to remove the device from blkio cgroup's per-device control files if it gets unplugged. To reproduce the bug: # mount -t cgroup -o blkio xxx /cgroup # cd /cgroup # echo "8:0 1000" > blkio.throttle.read_bps_device # unplug the device # cat blkio.throttle.read_bps_device 8:0 1000 # echo "8:0 0" > blkio.throttle.read_bps_device -bash: echo: write error: No such device After patching, the device removal will succeed. Thanks for the comments of Paul, Zefan, and Vivek. Signed-off-by: Wanlong Gao --- block/blk-cgroup.c | 37 ++++++++++++++++--------------------- 1 files changed, 16 insertions(+), 21 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index bcaf16e..b596e54 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -785,10 +785,10 @@ static int blkio_policy_parse_and_set(char *buf, { char *s[4], *p, *major_s = NULL, *minor_s = NULL; int ret; - unsigned long major, minor, temp; + unsigned long major, minor; int i = 0; dev_t dev; - u64 bps, iops; + u64 temp; memset(s, 0, sizeof(s)); @@ -826,20 +826,23 @@ static int blkio_policy_parse_and_set(char *buf, dev = MKDEV(major, minor); - ret = blkio_check_dev_num(dev); + ret = strict_strtoull(s[1], 10, &temp); if (ret) - return ret; + return -EINVAL; - newpn->dev = dev; + /* For rule removal, do not check for device presence. */ + if (temp) { + ret = blkio_check_dev_num(dev); + if (ret) + return ret; + } - if (s[1] == NULL) - return -EINVAL; + newpn->dev = dev; switch (plid) { case BLKIO_POLICY_PROP: - ret = strict_strtoul(s[1], 10, &temp); - if (ret || (temp < BLKIO_WEIGHT_MIN && temp > 0) || - temp > BLKIO_WEIGHT_MAX) + if ((temp < BLKIO_WEIGHT_MIN && temp > 0) || + temp > BLKIO_WEIGHT_MAX) return -EINVAL; newpn->plid = plid; @@ -850,26 +853,18 @@ static int blkio_policy_parse_and_set(char *buf, switch(fileid) { case BLKIO_THROTL_read_bps_device: case BLKIO_THROTL_write_bps_device: - ret = strict_strtoull(s[1], 10, &bps); - if (ret) - return -EINVAL; - newpn->plid = plid; newpn->fileid = fileid; - newpn->val.bps = bps; + newpn->val.bps = temp; break; case BLKIO_THROTL_read_iops_device: case BLKIO_THROTL_write_iops_device: - ret = strict_strtoull(s[1], 10, &iops); - if (ret) - return -EINVAL; - - if (iops > THROTL_IOPS_MAX) + if (temp > THROTL_IOPS_MAX) return -EINVAL; newpn->plid = plid; newpn->fileid = fileid; - newpn->val.iops = (unsigned int)iops; + newpn->val.iops = (unsigned int)temp; break; } break; -- 1.7.6