From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58111) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zz0W5-0001jq-1y for qemu-devel@nongnu.org; Wed, 18 Nov 2015 06:03:10 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Zz0W0-0002IP-VQ for qemu-devel@nongnu.org; Wed, 18 Nov 2015 06:03:08 -0500 Received: from mx1.redhat.com ([209.132.183.28]:37407) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zz0W0-0002IK-NV for qemu-devel@nongnu.org; Wed, 18 Nov 2015 06:03:04 -0500 From: Juan Quintela In-Reply-To: <1447751311-2317-5-git-send-email-den@openvz.org> (Denis V. Lunev's message of "Tue, 17 Nov 2015 12:08:24 +0300") References: <1447751311-2317-1-git-send-email-den@openvz.org> <1447751311-2317-5-git-send-email-den@openvz.org> Date: Wed, 18 Nov 2015 12:02:50 +0100 Message-ID: <87twojo9id.fsf@emacs.mitica> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Qemu-devel] [PATCH 04/11] snapshot: create bdrv_all_goto_snapshot helper Reply-To: quintela@redhat.com List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Denis V. Lunev" Cc: Kevin Wolf , qemu-devel@nongnu.org, stefanha@redhat.com "Denis V. Lunev" wrote: > to switch to snapshot on all loaded block drivers. > > The patch also ensures proper locking. > > Signed-off-by: Denis V. Lunev > Reviewed-by: Greg Kurz > Reviewed-by: Stefan Hajnoczi > Reviewed-by: Fam Zheng > CC: Juan Quintela > CC: Kevin Wolf Reviewed-by: Juan Quintela suggestion: un-export bdrv_snapshot_goto()? I haven't looked if it is used anywhere else, but looks like one idea. > --- > block/snapshot.c | 20 ++++++++++++++++++++ > include/block/snapshot.h | 1 + > migration/savevm.c | 15 +++++---------- > 3 files changed, 26 insertions(+), 10 deletions(-) > > diff --git a/block/snapshot.c b/block/snapshot.c > index 61a6ad1..9f07a63 100644 > --- a/block/snapshot.c > +++ b/block/snapshot.c > @@ -403,3 +403,23 @@ int bdrv_all_delete_snapshot(const char *name, BlockDriverState **first_bad_bs, > *first_bad_bs = bs; > return ret; > } > + > + > +int bdrv_all_goto_snapshot(const char *name, BlockDriverState **first_bad_bs) > +{ > + int err = 0; > + BlockDriverState *bs = NULL; > + > + while (err == 0 && (bs = bdrv_next(bs))) { > + AioContext *ctx = bdrv_get_aio_context(bs); > + > + aio_context_acquire(ctx); > + if (bdrv_can_snapshot(bs)) { > + err = bdrv_snapshot_goto(bs, name); > + } > + aio_context_release(ctx); > + } > + > + *first_bad_bs = bs; > + return err; > +} > diff --git a/include/block/snapshot.h b/include/block/snapshot.h > index d02d2b1..0a176c7 100644 > --- a/include/block/snapshot.h > +++ b/include/block/snapshot.h > @@ -84,5 +84,6 @@ int bdrv_snapshot_load_tmp_by_id_or_name(BlockDriverState *bs, > bool bdrv_all_can_snapshot(BlockDriverState **first_bad_bs); > int bdrv_all_delete_snapshot(const char *name, BlockDriverState **first_bsd_bs, > Error **err); > +int bdrv_all_goto_snapshot(const char *name, BlockDriverState **first_bsd_bs); > > #endif > diff --git a/migration/savevm.c b/migration/savevm.c > index c52cbbe..254e51d 100644 > --- a/migration/savevm.c > +++ b/migration/savevm.c > @@ -2093,16 +2093,11 @@ int load_vmstate(const char *name) > /* Flush all IO requests so they don't interfere with the new state. */ > bdrv_drain_all(); > > - bs = NULL; > - while ((bs = bdrv_next(bs))) { > - if (bdrv_can_snapshot(bs)) { > - ret = bdrv_snapshot_goto(bs, name); > - if (ret < 0) { > - error_report("Error %d while activating snapshot '%s' on '%s'", > - ret, name, bdrv_get_device_name(bs)); > - return ret; > - } > - } > + ret = bdrv_all_goto_snapshot(name, &bs); > + if (ret < 0) { > + error_report("Error %d while activating snapshot '%s' on '%s'", > + ret, name, bdrv_get_device_name(bs)); > + return ret; > } > > /* restore the VM state */