Messages in this thread | | | Date | Fri, 8 Apr 2016 09:05:28 +0200 (CEST) | From | Jiri Kosina <> | Subject | Re: sched: horrible way to detect whether a task has been preempted |
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On Thu, 7 Apr 2016, Jessica Yu wrote:
> > Alternatively, without eating up a TIF_ space, it'd be possible to push a > > magic contents on top of the stack in preempt_schedule_irq() (and pop it > > once we are returning from there), and if such magic value is detected, we > > just don't bother and claim unreliability. > > Ah, but wouldn't we still have to walk through the frames (i.e. enter > the loop in patch 7/14) to look for the magic value in this approach?
The idea was that it'd be located at a place to which saved stack pointer of the sleeping task is pointing to (or at a fixed offset from it).
-- Jiri Kosina SUSE Labs
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