Re: [PATCH 1/2 v3] wait: add wait_event_lock_irq() interface

[Andrew Morton <akpm@linux-foundation.org>]

On Fri, 30 Nov 2012 11:42:40 +0100 Lukas Czerner <lczerner@redhat.com> wrote:

> New wait_event{_interruptible}_lock_irq{_cmd} macros added. This commit
> moves the private wait_event_lock_irq() macro from MD to regular wait
> includes, introduces new macro wait_event_lock_irq_cmd() instead of using
> the old method with omitting cmd parameter which is ugly and makes a use
> of new macros in the MD. It also introduces the _interruptible_ variant.
> 
> The use of new interface is when one have a special lock to protect data
> structures used in the condition, or one also needs to invoke "cmd"
> before putting it to sleep.
> 
> All new macros are expected to be called with the lock taken. The lock
> is released before sleep and is reacquired afterwards. We will leave the
> macro with the lock held.
> 
> Note to DM: IMO this should also fix theoretical race on waitqueue while
> using simultaneously wait_event_lock_irq() and wait_event() because of
> lack of locking around current state setting and wait queue removal.

Does this fix the sparse warning which Fengguang just sent us?