From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:51230) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RzPSq-0004vM-0G for qemu-devel@nongnu.org; Mon, 20 Feb 2012 04:23:25 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RzPSJ-0005VN-7K for qemu-devel@nongnu.org; Mon, 20 Feb 2012 04:23:19 -0500 Received: from mx1.redhat.com ([209.132.183.28]:26142) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RzPSJ-0005VA-0a for qemu-devel@nongnu.org; Mon, 20 Feb 2012 04:22:47 -0500 Message-ID: <4F4211AF.9000009@redhat.com> Date: Mon, 20 Feb 2012 10:26:07 +0100 From: Kevin Wolf MIME-Version: 1.0 References: <1329713430-9209-1-git-send-email-zwu.kernel@gmail.com> In-Reply-To: <1329713430-9209-1-git-send-email-zwu.kernel@gmail.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 1/2] block: add the support for draining the throttled request queue List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: zwu.kernel@gmail.com Cc: chris@arachsys.com, Zhi Yong Wu , qemu-devel@nongnu.org, stefanha@linux.vnet.ibm.com Am 20.02.2012 05:50, schrieb zwu.kernel@gmail.com: > From: Zhi Yong Wu > > If one guest has multiple disks with enabling I/O throttling function separately, when draining activities are done, some requests maybe are in the throttled queue; So we need to restart them at first. > > Moreover, when only one disk need to be drained such as hotplug out, if another disk still has some requests in its throttled queue, these request should not be effected. > > Signed-off-by: Zhi Yong Wu > --- > block.c | 29 ++++++++++++++++++++++------- > block_int.h | 1 + > 2 files changed, 23 insertions(+), 7 deletions(-) > > diff --git a/block.c b/block.c > index ae297bb..f78df78 100644 > --- a/block.c > +++ b/block.c > @@ -853,25 +853,40 @@ void bdrv_close_all(void) > } > } > > -/* > - * Wait for pending requests to complete across all BlockDriverStates > - * > - * This function does not flush data to disk, use bdrv_flush_all() for that > - * after calling this function. > - */ > -void bdrv_drain_all(void) > +void bdrv_drain_request(BlockDriverState *throttled_bs) > { > BlockDriverState *bs; > > + QTAILQ_FOREACH(bs, &bdrv_states, list) { > + if (throttled_bs && throttled_bs != bs) { > + continue; > + } > + qemu_co_queue_restart_all(&bs->throttled_reqs); > + } > + > qemu_aio_flush(); Why doesn't qemu_aio_flush() invoke whatever is needed? I think this is the real bug that should be fixed. Kevin