Quoting Tvrtko Ursulin (2020-12-18 08:49:39) > From: Tvrtko Ursulin <tvrtko.ursu...@intel.com> > > Ask for CLOCK_MONOTONIC which is more stable than the default perf clock. > > (Ability to select a clock has been available since kernel version 4.1.) > > The change should not have any significant impact on the IGT as whole > apart from maybe improving the occasional jitter in tests/tools which use > nanosleep(2) and use time slept together with perf reported time delta > either in direct or indirect calculations. > > Signed-off-by: Tvrtko Ursulin <tvrtko.ursu...@intel.com> > --- > lib/igt_perf.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/lib/igt_perf.c b/lib/igt_perf.c > index 418c1c18891c..b743859f5d29 100644 > --- a/lib/igt_perf.c > +++ b/lib/igt_perf.c > @@ -1,12 +1,13 @@ > -#include <stdint.h> > +#include <errno.h> > #include <fcntl.h> > -#include <unistd.h> > +#include <stdint.h> > #include <stdlib.h> > #include <string.h> > -#include <errno.h> > #include <sys/stat.h> > #include <sys/sysinfo.h> > #include <sys/sysmacros.h> > +#include <time.h> > +#include <unistd.h> > > #include "igt_perf.h" > > @@ -111,6 +112,8 @@ _perf_open(uint64_t type, uint64_t config, int group, > uint64_t format) > > attr.read_format = format; > attr.config = config; > + attr.use_clockid = 1; > + attr.clockid = CLOCK_MONOTONIC;
Ok, pretty much all are cumulative samples with ktime_get(), and not raw HW clocks that would prefer MONO_RAW. Reviewed-by: Chris Wilson <ch...@chris-wilson.co.uk> -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx