| Message ID | 1473957290-13382-3-git-send-email-den@openvz.org |
|---|---|
| State | New |
| Headers | show |
On 09/15/2016 11:34 AM, Denis V. Lunev wrote: > bdrv_is_allocated_above() returns true in the case even for completel s/completel/completely/ > zeroed areas as BDRV_BLOCK_ALLOCATED flag is set in both cases. > > The patch stops using bdrv_is_allocated_above() wrapper and switches to > bdrv_get_block_status_above() to distinguish zeroed areas and areas with > data to avoid extra IO operations if possible. > > Signed-off-by: Denis V. Lunev <den@openvz.org> > CC: Stefan Hajnoczi <stefanha@redhat.com> > CC: Fam Zheng <famz@redhat.com> > CC: Kevin Wolf <kwolf@redhat.com> > CC: Max Reitz <mreitz@redhat.com> > CC: Jeff Cody <jcody@redhat.com> > --- > block/mirror.c | 17 +++++++++++------ > 1 file changed, 11 insertions(+), 6 deletions(-)
On 15.09.2016 19:34, Denis V. Lunev wrote: > bdrv_is_allocated_above() returns true in the case even for completel > zeroed areas as BDRV_BLOCK_ALLOCATED flag is set in both cases. > > The patch stops using bdrv_is_allocated_above() wrapper and switches to > bdrv_get_block_status_above() to distinguish zeroed areas and areas with > data to avoid extra IO operations if possible. > > Signed-off-by: Denis V. Lunev <den@openvz.org> > CC: Stefan Hajnoczi <stefanha@redhat.com> > CC: Fam Zheng <famz@redhat.com> > CC: Kevin Wolf <kwolf@redhat.com> > CC: Max Reitz <mreitz@redhat.com> > CC: Jeff Cody <jcody@redhat.com> > --- > block/mirror.c | 17 +++++++++++------ > 1 file changed, 11 insertions(+), 6 deletions(-) > > diff --git a/block/mirror.c b/block/mirror.c > index e0b3f41..2710f62 100644 > --- a/block/mirror.c > +++ b/block/mirror.c > @@ -548,11 +548,11 @@ static void mirror_throttle(MirrorBlockJob *s) > > static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) > { > - int64_t sector_num, end; > + int64_t sector_num, end, alloc_mask; > BlockDriverState *base = s->base; > BlockDriverState *bs = blk_bs(s->common.blk); > BlockDriverState *target_bs = blk_bs(s->target); > - int ret, n; > + int n; > > end = s->bdev_length / BDRV_SECTOR_SIZE; > > @@ -585,11 +585,15 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) > mirror_drain(s); > } > > + alloc_mask = base == NULL ? BDRV_BLOCK_ALLOCATED : BDRV_BLOCK_DATA; should not s/==/!= ? > + > /* First part, loop on the sectors and initialize the dirty bitmap. */ > for (sector_num = 0; sector_num < end; ) { > /* Just to make sure we are not exceeding int limit. */ > int nb_sectors = MIN(INT_MAX >> BDRV_SECTOR_BITS, > end - sector_num); > + int64_t status; > + BlockDriverState *file; > > mirror_throttle(s); > > @@ -597,13 +601,14 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) > return 0; > } > > - ret = bdrv_is_allocated_above(bs, base, sector_num, nb_sectors, &n); > - if (ret < 0) { > - return ret; > + status = bdrv_get_block_status_above(bs, base, sector_num, > + nb_sectors, &n, &file); > + if (status < 0) { > + return status; > } > > assert(n > 0); > - if (ret == 1) { > + if (status & alloc_mask) { > bdrv_set_dirty_bitmap(s->dirty_bitmap, sector_num, n); > } > sector_num += n;
diff --git a/block/mirror.c b/block/mirror.c index e0b3f41..2710f62 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -548,11 +548,11 @@ static void mirror_throttle(MirrorBlockJob *s) static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) { - int64_t sector_num, end; + int64_t sector_num, end, alloc_mask; BlockDriverState *base = s->base; BlockDriverState *bs = blk_bs(s->common.blk); BlockDriverState *target_bs = blk_bs(s->target); - int ret, n; + int n; end = s->bdev_length / BDRV_SECTOR_SIZE; @@ -585,11 +585,15 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) mirror_drain(s); } + alloc_mask = base == NULL ? BDRV_BLOCK_ALLOCATED : BDRV_BLOCK_DATA; + /* First part, loop on the sectors and initialize the dirty bitmap. */ for (sector_num = 0; sector_num < end; ) { /* Just to make sure we are not exceeding int limit. */ int nb_sectors = MIN(INT_MAX >> BDRV_SECTOR_BITS, end - sector_num); + int64_t status; + BlockDriverState *file; mirror_throttle(s); @@ -597,13 +601,14 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) return 0; } - ret = bdrv_is_allocated_above(bs, base, sector_num, nb_sectors, &n); - if (ret < 0) { - return ret; + status = bdrv_get_block_status_above(bs, base, sector_num, + nb_sectors, &n, &file); + if (status < 0) { + return status; } assert(n > 0); - if (ret == 1) { + if (status & alloc_mask) { bdrv_set_dirty_bitmap(s->dirty_bitmap, sector_num, n); } sector_num += n;
bdrv_is_allocated_above() returns true in the case even for completel zeroed areas as BDRV_BLOCK_ALLOCATED flag is set in both cases. The patch stops using bdrv_is_allocated_above() wrapper and switches to bdrv_get_block_status_above() to distinguish zeroed areas and areas with data to avoid extra IO operations if possible. Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Fam Zheng <famz@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> CC: Max Reitz <mreitz@redhat.com> CC: Jeff Cody <jcody@redhat.com> --- block/mirror.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-)