diff options
| author | Vivek Goyal <vgoyal@redhat.com> | 2010-10-01 14:49:49 +0200 |
|---|---|---|
| committer | Jens Axboe <jaxboe@fusionio.com> | 2010-10-01 14:49:49 +0200 |
| commit | fe0714377ee2ca161bf2afb7773e22f15f1786d4 (patch) | |
| tree | 09f5e8686d741d012333c92251b8cc66793ef916 /block/blk-cgroup.c | |
| parent | 02977e4af7ed3b478c505e50491ffdf3e1314cf4 (diff) | |
| download | linux-fe0714377ee2ca161bf2afb7773e22f15f1786d4.tar.bz2 | |
blkio: Recalculate the throttled bio dispatch time upon throttle limit change
o Currently any cgroup throttle limit changes are processed asynchronousy and
the change does not take affect till a new bio is dispatched from same group.
o It might happen that a user sets a redicuously low limit on throttling.
Say 1 bytes per second on reads. In such cases simple operations like mount
a disk can wait for a very long time.
o Once bio is throttled, there is no easy way to come out of that wait even if
user increases the read limit later.
o This patch fixes it. Now if a user changes the cgroup limits, we recalculate
the bio dispatch time according to new limits.
o Can't take queueu lock under blkcg_lock, hence after the change I wake
up the dispatch thread again which recalculates the time. So there are some
variables being synchronized across two threads without lock and I had to
make use of barriers. Hoping I have used barriers correctly. Any review of
memory barrier code especially will help.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Diffstat (limited to 'block/blk-cgroup.c')
| -rw-r--r-- | block/blk-cgroup.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index b06ca70354e3..52c12130a5de 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -124,7 +124,8 @@ blkio_update_group_weight(struct blkio_group *blkg, unsigned int weight) if (blkiop->plid != blkg->plid) continue; if (blkiop->ops.blkio_update_group_weight_fn) - blkiop->ops.blkio_update_group_weight_fn(blkg, weight); + blkiop->ops.blkio_update_group_weight_fn(blkg->key, + blkg, weight); } } @@ -141,11 +142,13 @@ static inline void blkio_update_group_bps(struct blkio_group *blkg, u64 bps, if (fileid == BLKIO_THROTL_read_bps_device && blkiop->ops.blkio_update_group_read_bps_fn) - blkiop->ops.blkio_update_group_read_bps_fn(blkg, bps); + blkiop->ops.blkio_update_group_read_bps_fn(blkg->key, + blkg, bps); if (fileid == BLKIO_THROTL_write_bps_device && blkiop->ops.blkio_update_group_write_bps_fn) - blkiop->ops.blkio_update_group_write_bps_fn(blkg, bps); + blkiop->ops.blkio_update_group_write_bps_fn(blkg->key, + blkg, bps); } } @@ -162,11 +165,13 @@ static inline void blkio_update_group_iops(struct blkio_group *blkg, if (fileid == BLKIO_THROTL_read_iops_device && blkiop->ops.blkio_update_group_read_iops_fn) - blkiop->ops.blkio_update_group_read_iops_fn(blkg, iops); + blkiop->ops.blkio_update_group_read_iops_fn(blkg->key, + blkg, iops); if (fileid == BLKIO_THROTL_write_iops_device && blkiop->ops.blkio_update_group_write_iops_fn) - blkiop->ops.blkio_update_group_write_iops_fn(blkg,iops); + blkiop->ops.blkio_update_group_write_iops_fn(blkg->key, + blkg,iops); } } |