Re: [PATCH 1/1] perf tools: Fix format value calculation

From: Jiri Olsa
Date: Mon Apr 04 2016 - 20:16:49 EST


On Mon, Apr 04, 2016 at 06:12:54AM -0700, kan.liang@xxxxxxxxx wrote:
> From: Kan Liang <kan.liang@xxxxxxxxx>
>
> The calculation of format value also rely on the continuity of the
> format. However, uncore event format is not continuous.
> E.g. The bit 21 as qpi event is lost.
>
> perf stat -a -e uncore_qpi_0/event=0x200038,config1=0x1C00,
> config2=0x3FE00/ -vvv
> ------------------------------------------------------------
> perf_event_attr:
> type 10
> size 112
> config 0x38

could you please share the event's format?

would be great to have some simple automated test for this one..

thanks,
jirka

>
>
>
> This patch checks the bit according to the bit position.
>
> Signed-off-by: Kan Liang <kan.liang@xxxxxxxxx>
> ---
> tools/perf/util/pmu.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
> index bf34468..47c096c 100644
> --- a/tools/perf/util/pmu.c
> +++ b/tools/perf/util/pmu.c
> @@ -586,14 +586,14 @@ __u64 perf_pmu__format_bits(struct list_head *formats, const char *name)
> static void pmu_format_value(unsigned long *format, __u64 value, __u64 *v,
> bool zero)
> {
> - unsigned long fbit, vbit;
> + unsigned long fbit;
>
> - for (fbit = 0, vbit = 0; fbit < PERF_PMU_FORMAT_BITS; fbit++) {
> + for (fbit = 0; fbit < PERF_PMU_FORMAT_BITS; fbit++) {
>
> if (!test_bit(fbit, format))
> continue;
>
> - if (value & (1llu << vbit++))
> + if (value & (1llu << fbit))
> *v |= (1llu << fbit);
> else if (zero)
> *v &= ~(1llu << fbit);
> --
> 2.5.5
>