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SubjectRe: [PATCH 4/5] Powerpc/hw-breakpoint: Optimize disable path
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On 6/18/19 11:45 AM, Michael Neuling wrote:
> On Tue, 2019-06-18 at 09:57 +0530, Ravi Bangoria wrote:
>> Directly setting dawr and dawrx with 0 should be enough to
>> disable watchpoint. No need to reset individual bits in
>> variable and then set in hw.
>
> This seems like a pointless optimisation to me.
>
> I'm all for adding more code/complexity if it buys us some performance, but I
> can't imagine this is a fast path (nor have you stated any performance
> benefits).

This gets called from sched_switch. I expected the improvement when
we switch from monitored process to non-monitored process. With such
scenario, I tried to measure the difference in execution time of
set_dawr but I don't see any improvement. So I'll drop the patch.

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