lkml.org 
[lkml]   [2014]   [Nov]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    SubjectRe: [PATCH v3 1/3] perf: Use monotonic clock as a source for timestamps
    On Tue, Nov 04, 2014 at 12:28:36AM +0000, Pawel Moll wrote:

    > +int sysctl_perf_sample_time_clk_id = CLOCK_MONOTONIC;

    const ?

    > /*
    > * perf samples are done in some very critical code paths (NMIs).
    > * If they take too much CPU time, the system can lock up and not
    > @@ -324,7 +326,7 @@ extern __weak const char *perf_pmu_name(void)
    >
    > static inline u64 perf_clock(void)
    > {
    > - return local_clock();
    > + return ktime_get_mono_fast_ns();
    > }

    Do we maybe want to make it boot-time switchable back to local_clock for
    people with bad systems and or backwards compat issues?

    Everybody using Core2 and older will very much not want to have this
    unless they've got a very good reason for wanting it.


    \
     
     \ /
      Last update: 2014-11-04 08:41    [W:3.727 / U:0.376 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site