tree c4cbbc37e357775fc8200e16c6eb9b3f14d30069
parent cf82c798394cd443eed7d91f998b79a63f341e91
author Jens Axboe <jaxboe@fusionio.com> 1302613131 +0200
committer Jens Axboe <jaxboe@fusionio.com> 1302613131 +0200

block: move queue run on unplug to kblockd

There are worries that we are now consuming a lot more stack in
some cases, since we potentially call into IO dispatch from
schedule() or io_schedule(). We can reduce this problem by moving
the running of the queue to kblockd, like the old plugging scheme
did as well.

This may or may not be a good idea from a performance perspective,
depending on how many tasks have queue plugs running at the same
time. For even the slightly contended case, doing just a single
queue run from kblockd instead of multiple runs directly from the
unpluggers will be faster.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>