Re: [PATCH V3 2/2] perf/x86/intel/uncore: add enable_box for client msr uncore

From: Ingo Molnar
Date: Wed Aug 10 2016 - 16:16:09 EST



* kan.liang@xxxxxxxxx <kan.liang@xxxxxxxxx> wrote:

> From: Kan Liang <kan.liang@xxxxxxxxx>
>
> PERF_GLOBAL_CTL could be cleared after Package C7. This patch tries to
> workaround this issue by re-enable PERF_GLOBAL_CTL in enable_box.
> The workaround does not cover all cases. It helps for new events after
> returning from C7.
> There is no drawback in letting the thing enabled, so it does not need
> disable_box here.

This changelog is very poor for similar reasons as:

Re: [PATCH] perf/x86/intel/uncore: correct uncore num_counters

Please fix the changelog to conform to the standard changelog style:

- first describe the symptoms of the bug - how does a user notice?

- then describe how the code behaves today and how that is causing the bug

- and then only describe how it's fixed.

The first item is the most important one - while developers
(naturally) tend to concentrate on the least important point, the last
one.

Thanks,

Ingo