lkml.org 
[lkml]   [2006]   [Nov]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 1/13] BC: atomic_dec_and_lock_irqsave() helper
Hello Kirill, Hello Pavel,

Kirill Korotaev wrote:
> Oleg Nesterov noticed to me that the construction like
> (used in beancounter patches and free_uid()):
>
> local_irq_save(flags);
> if (atomic_dec_and_lock(&refcnt, &lock))
> ...
>
> is not that good for preemtible kernels, since with preemption
> spin_lock() can schedule() to reduce latency. However, it won't schedule
> if interrupts are disabled.
>
> So this patch introduces atomic_dec_and_lock_irqsave() as a logical
> counterpart to atomic_dec_and_lock().

You should probably send that one independently from the BC
patchset.

C.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-11-10 16:23    [from the cache]
©2003-2011 Jasper Spaans