[PATCH 47/49] xfs: split the CIL lock

[Mark Tinguely]

On 07/19/13 01:25, Dave Chinner wrote:
> From: Dave Chinner<dchinner at redhat.com>
>
> The xc_cil_lock is used for two purposes - to protect the CIL
> itself, and to protect the push/commit state and lists. These are
> two logically separate structures and operations, so can have their
> own locks. This means that pushing on the CIL and the commit wait
> ordering won't contend for a lock with other transactions that are
> completing concurrently. As the CIL insertion is the hottest path
> throught eh CIL, this is a big win.
>
> Signed-off-by: Dave Chinner<dchinner at redhat.com>
> ---

read semaphore/xc_cil_lock (original lock) protects cil entries
write semaphore/xc_push_lock (new lock) protects the cil push

Looks good.

Review-by: Mark Tinguely <tinguely at sgi.com>