lkml.org 
[lkml]   [2019]   [May]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC 4/7] arm64: pmu: Add function implementation to update event index in userpage.
On Tue, May 28, 2019 at 04:03:17PM +0100, Raphael Gault wrote:
> +static int armv8pmu_access_event_idx(struct perf_event *event)
> +{
> + if (!(event->hw.flags & ARMPMU_EL0_RD_CNTR))
> + return 0;
> +
> + /*
> + * We remap the cycle counter index to 32 to
> + * match the offset applied to the rest of
> + * the counter indeces.
> + */
> + if (event->hw.idx == ARMV8_IDX_CYCLE_COUNTER)
> + return 32;
> +
> + return event->hw.idx;

Is there a guarantee event->hw.idx is never 0? Or should you, just like
x86, use +1 here?

> +}

\
 
 \ /
  Last update: 2019-05-29 11:47    [W:0.133 / U:0.240 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site