From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753377Ab1HQM6M (ORCPT ); Wed, 17 Aug 2011 08:58:12 -0400 Received: from mail-pz0-f42.google.com ([209.85.210.42]:37620 "EHLO mail-pz0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752864Ab1HQM6J (ORCPT ); Wed, 17 Aug 2011 08:58:09 -0400 Subject: Re: [PATCH v5] blk-cgroup:be able to remove the record of unplugged device From: Wanlong Gao Reply-To: wanlong.gao@gmail.com To: Vivek Goyal Cc: Wanlong Gao , Paul Menage , lizf@cn.fujitsu.com, axboe@kernel.dk, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, torvalds@linux-foundation.org In-Reply-To: <20110727141142.GA17743@redhat.com> References: <20110726192441.GD13780@redhat.com> <1311725508-4419-1-git-send-email-gaowanlong@cn.fujitsu.com> <20110727141142.GA17743@redhat.com> Content-Type: text/plain; charset="UTF-8" Organization: FNST Date: Wed, 17 Aug 2011 20:57:45 +0800 Message-ID: <1313585865.1807.2.camel@Allen> Mime-Version: 1.0 X-Mailer: Evolution 2.32.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2011-07-27 at 10:11 -0400, Vivek Goyal wrote: > On Wed, Jul 27, 2011 at 08:11:48AM +0800, Wanlong Gao wrote: > > 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 > > Thanks. This looks good to me. > > Acked-by: Vivek Goyal > > Vivek > > > --- > > 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 How about this? For a long time. Thanks Wanlong Gao