Re: [PATCH] sched: Update task->on_rq when tasks are moving between runqueues

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 15-10-25 11:09:24, Peter Zijlstra wrote:
> On Sat, Oct 24, 2015 at 11:01:02AM -0700, Olav Haugan wrote:
> > Task->on_rq has three states:
> > 	0 - Task is not on runqueue (rq)
> > 	1 (TASK_ON_RQ_QUEUED) - Task is on rq
> > 	2 (TASK_ON_RQ_MIGRATING) - Task is on rq but in the process of being
> > 	migrated to another rq
> > 
> > When a task is moving between rqs task->on_rq state should be
> > TASK_ON_RQ_MIGRATING
> 
> Only when not holding both rq locks..

IMHO I think we should keep the state of p->on_rq updated with the correct state
all the time unless I am incorrect in what p->on_rq represent. The task
is moving between rq's and is on the rq so the state should be
TASK_ON_RQ_MIGRATING right? I do realize that the code is currently not
broken. However, in the future someone might come along and change
set_task_cpu() and the code change might rely on an accurate p->on_rq value. It
would be good design to keep this value correct.

Thanks,

-- 
.Olav

The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project
--
To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [Linux for Sparc]     [IETF Annouce]     [Security]     [Bugtraq]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux