450adcbe51
o Dominik Klein reported a system hang issue while doing some blkio throttling testing. https://lkml.org/lkml/2011/2/24/173 o Some tracing revealed that CFQ was not dispatching any more jobs as queue unplug was not happening. And queue unplug was not happening because unplug work was not being called as there was one throttling work on same cpu which as not finished yet. And throttling work had not finished as it was tyring to dispatch a bio to CFQ but all the request descriptors were consume to it was put to sleep. o So basically it is a cyclic dependecny between CFQ unplug work and throtl dispatch work. Tejun suggested that use separate workqueue for such cases. o This patch uses a separate workqueue for throttle related work and does not rely on kblockd workqueue anymore. Cc: stable@kernel.org Reported-by: Dominik Klein <dk@in-telegence.net> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com> |
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| .. | ||
| Kconfig | ||
| Kconfig.iosched | ||
| Makefile | ||
| blk-cgroup.c | ||
| blk-cgroup.h | ||
| blk-core.c | ||
| blk-exec.c | ||
| blk-flush.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 | ||
| noop-iosched.c | ||
| scsi_ioctl.c | ||