Re: [patch 01/16] RCU read sched notrace

Paul E. McKenney
2008-11-16T04:00:38Z

On Fri, Nov 14, 2008 at 05:47:34PM -0500, Mathieu Desnoyers wrote:
> Add _notrace version to rcu_read_*_sched().
>
> Impact: new API, useful for tracepoints and markers.

Looks good to me. Just don't try it with rcu_read_lock(), given
preemptable RCU. ;-)

Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
> CC: Peter Zijlstra <peterz@infradead.org>
> CC: Paul E McKenney <paulmck@linux.vnet.ibm.com>
> CC: 'Ingo Molnar' <mingo@elte.hu>
> CC: akpm@linux-foundation.org
> ---
> include/linux/rcupdate.h | 2 ++
> 1 file changed, 2 insertions(+)
>
> Index: linux-2.6-lttng/include/linux/rcupdate.h
> ===================================================================
> --- linux-2.6-lttng.orig/include/linux/rcupdate.h 2008-10-08 10:27:57.000000000 -0400
> +++ linux-2.6-lttng/include/linux/rcupdate.h 2008-10-08 10:40:48.000000000 -0400
> @@ -142,6 +142,7 @@ struct rcu_head {
> * on the write-side to insure proper synchronization.
> */
> #define rcu_read_lock_sched() preempt_disable()
> +#define rcu_read_lock_sched_notrace() preempt_disable_notrace()
>
> /*
> * rcu_read_unlock_sched - marks the end of a RCU-classic critical section
> @@ -149,6 +150,7 @@ struct rcu_head {
> * See rcu_read_lock_sched for more information.
> */
> #define rcu_read_unlock_sched() preempt_enable()
> +#define rcu_read_unlock_sched_notrace() preempt_enable_notrace()
>
>
>
>
> --
> Mathieu Desnoyers
> OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68