Messages in this thread | ![/](/images/icornerl.gif) | | Date | Wed, 20 Apr 2022 13:56:07 -0700 | From | Dave Hansen <> | Subject | Re: [PATCH v3 6/9] x86: resctrl: pseudo_lock: Fix to restore to original value when re-enabling hardware prefetch register |
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On 4/19/22 20:02, Kohei Tarumizu wrote: > The current pseudo_lock.c code overwrittes the value of the > MSR_MISC_FEATURE_CONTROL to 0 even if the original value is not 0. > Therefore, modify it to save and restore the original values.
It would be nice to mention that the wrmsr()'s in this patch are only done inside of an interrupt-disabled region. Without that little tidbit of information, it's not obviously correct that the smp_call_function() in patch 8/9 is correct.
The x86 code here looks reasonable otherwise. It's a little bit of a shame that this is *ONLY* for BROADWELL_X for now, but I assume you were just conservative about it because that's all you have to test on.
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