forked from luck/tmp_suning_uos_patched
fe0714377e
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> |
||
---|---|---|
.. | ||
blk-barrier.c | ||
blk-cgroup.c | ||
blk-cgroup.h | ||
blk-core.c | ||
blk-exec.c | ||
blk-integrity.c | ||
blk-ioc.c | ||
blk-iopoll.c | ||
blk-lib.c | ||
blk-map.c | ||
blk-merge.c | ||
blk-settings.c | ||
blk-softirq.c | ||
blk-sysfs.c | ||
blk-tag.c | ||
blk-throttle.c | ||
blk-timeout.c | ||
blk.h | ||
bsg.c | ||
cfq-iosched.c | ||
cfq.h | ||
compat_ioctl.c | ||
deadline-iosched.c | ||
elevator.c | ||
genhd.c | ||
ioctl.c | ||
Kconfig | ||
Kconfig.iosched | ||
Makefile | ||
noop-iosched.c | ||
scsi_ioctl.c |