Re: [tip:sched/core] sched/rt: Reduce rq lock contention by eliminating locking of non-feasible target

[Zefan Li <lizefan@huawei.com>]

>> Commit-ID:  80e3d87b2c5582db0ab5e39610ce3707d97ba409
>> Gitweb:     http://git.kernel.org/tip/80e3d87b2c5582db0ab5e39610ce3707d97ba409
>> Author:     Tim Chen <tim.c.chen@linux.intel.com>
>> AuthorDate: Fri, 12 Dec 2014 15:38:12 -0800
>> Committer:  Ingo Molnar <mingo@kernel.org>
>> CommitDate: Fri, 30 Jan 2015 19:38:49 +0100
>>
>> sched/rt: Reduce rq lock contention by eliminating locking of non-feasible target
>>
>> This patch adds checks that prevens futile attempts to move rt tasks
>> to a CPU with active tasks of equal or higher priority.
>>
>> This reduces run queue lock contention and improves the performance of
>> a well known OLTP benchmark by 0.7%.
>>
>> Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
>> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
>> Cc: Shawn Bohrer <sbohrer@rgmadvisors.com>
>> Cc: Suruchi Kadu <suruchi.a.kadu@intel.com>
>> Cc: Doug Nelson<doug.nelson@intel.com>
>> Cc: Steven Rostedt <rostedt@goodmis.org>
>> Cc: Linus Torvalds <torvalds@linux-foundation.org>
>> Link: http://lkml.kernel.org/r/1421430374.2399.27.camel@schen9-desk2.jf.intel.com
>> Signed-off-by: Ingo Molnar <mingo@kernel.org>
> 
> I see this has been added to mainline already. I think this should go
> to stable as well. As far back as it applies. I'll even add this to the
> stable-rt if need be. But I rather pull it into stable-rt via the
> stable branches.
> 

Queued up for 3.4. Thanks!