Re: contention on long-held spinlock

[Andi Kleen]

Ortwin GlÃck <odi@xxxxxx> writes:
>
> I wonder if spinlocks could be made aware of such a situation and
> relax. Something like if spinning for more than 1000 times, perform a
> simple backoff and sleep. A spinlock should never spin busy for
> several seconds, right?

Spining for several seconds is always a bug. There's no way to make
this work. Please post backtraces (e.g. from perf record -g ; perf
report) and cc the driver maintainer, so that they can fix their
buggy code.

-Andi


-- 
ak@xxxxxxxxxxxxxxx -- Speaking for myself only
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