* Ramkumar Ramachandra <[email protected]> wrote: > When only the cycles event is requested: > > $ perf stat -e cycles dd if=/dev/zero of=/dev/null count=1000000 > 1000000+0 records in > 1000000+0 records out > 512000000 bytes (512 MB) copied, 0.26123 s, 2.0 GB/s > > Performance counter stats for 'dd if=/dev/zero of=/dev/null count=1000000': > > 911,626,453 cycles # 0.000 GHz > > 0.262113350 seconds time elapsed > > The 0.000 GHz comment in the output is totally bogus and misleading. It > happens because update_shadow_stats() doesn't touch runtime_nsecs_stats; > it is only written when a requested counter matches a SW_TASK_CLOCK. In > our case, since we have only requested HW_CPU_CYCLES, > runtime_nsecs_stats is unavailable. So, omit printing the comment > altogether. > > Cc: Ingo Molnar <[email protected]> > Cc: Peter Zijlstra <[email protected]> > Cc: Paul Mackerras <[email protected]> > Cc: Arnaldo Carvalho de Melo <[email protected]> > Signed-off-by: Ramkumar Ramachandra <[email protected]> > --- > tools/perf/builtin-stat.c | 9 ++++----- > 1 file changed, 4 insertions(+), 5 deletions(-)
Acked-by: Ingo Molnar <[email protected]> Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
