dm snapshot: persistent make metadata_wq multithreaded
authorTejun Heo <tj@kernel.org>
Thu, 13 Jan 2011 19:59:59 +0000 (19:59 +0000)
committerAlasdair G Kergon <agk@redhat.com>
Thu, 13 Jan 2011 19:59:59 +0000 (19:59 +0000)
commit239c8dd533e74de4a7f3c85c4f9f430eb08867c1
tree0dfb9e39aad0f2ab09a4f278a6e7f1b46bf64307
parent9c4376de98719d2768dd919553843de34bb094a6
dm snapshot: persistent make metadata_wq multithreaded

metadata_wq serves on-stack work items from chunk_io().  Even if
multiple chunk_io() are simultaneously in progress, each is
independent and queued only once, so multithreaded workqueue can be
safely used.

Switch metadata_wq to multithread and flush the work item instead of
the workqueue in chunk_io().

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
drivers/md/dm-snap-persistent.c