Commit Graph

4 Commits

Author SHA1 Message Date
Jens Axboe 581d4e28d9 block: add fault injection mechanism for faking request timeouts
Only works for the generic request timer handling. Allows one to
sporadically ignore request completions, thus exercising the timeout
handling.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:17 +02:00
Jens Axboe 242f9dcb8b block: unify request timeout handling
Right now SCSI and others do their own command timeout handling.
Move those bits to the block layer.

Instead of having a timer per command, we try to be a bit more clever
and simply have one per-queue. This avoids the overhead of having to
tear down and setup a timer for each command, so it will result in a lot
less timer fiddling.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:13 +02:00
Jens Axboe c7c22e4d5c block: add support for IO CPU affinity
This patch adds support for controlling the IO completion CPU of
either all requests on a queue, or on a per-request basis. We export
a sysfs variable (rq_affinity) which, if set, migrates completions
of requests to the CPU that originally submitted it. A bio helper
(bio_set_completion_cpu()) is also added, so that queuers can ask
for completion on that specific CPU.

In testing, this has been show to cut the system time by as much
as 20-40% on synthetic workloads where CPU affinity is desired.

This requires a little help from the architecture, so it'll only
work as designed for archs that are using the new generic smp
helper infrastructure.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:09 +02:00
Jens Axboe b646fc59b3 block: split softirq handling into blk-softirq.c
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:09 +02:00