Re: [PATCH v3 4/8] perf cs-etm: Fix bitmap for option

Mathieu Poirier
2021-02-08T20:48:07Z

On Sat, Feb 06, 2021 at 11:08:29PM +0800, Leo Yan wrote:
> From: Suzuki K Poulose <suzuki.poulose@arm.com>
>
> When set option with macros ETM_OPT_CTXTID and ETM_OPT_TS, it wrongly
> takes these two values (14 and 28 prespectively) as bit masks, but
> actually both are the offset for bits. But this doesn't lead to
> further failure due to the AND logic operation will be always true for
> ETM_OPT_CTXTID / ETM_OPT_TS.
>
> This patch defines new independent macros (rather than using the
> "config" bits) for requesting the "contextid" and "timestamp" for
> cs_etm_set_option().
>
> [leoy: Extract the change as a separate patch for easier review]

This should go just above your name - see below.

> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> Signed-off-by: Leo Yan <leo.yan@linaro.org>
> Reviewed-by: Mike Leach <mike.leach@linaro.org>

Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
[Extract the change as a separate patch for easier review]
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mike Leach <mike.leach@linaro.org>

> ---
> tools/perf/arch/arm/util/cs-etm.c | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/tools/perf/arch/arm/util/cs-etm.c b/tools/perf/arch/arm/util/cs-etm.c
> index bd446aba64f7..c25c878fd06c 100644
> --- a/tools/perf/arch/arm/util/cs-etm.c
> +++ b/tools/perf/arch/arm/util/cs-etm.c
> @@ -156,6 +156,10 @@ static int cs_etm_set_timestamp(struct auxtrace_record *itr,
> return err;
> }
>
> +#define ETM_SET_OPT_CTXTID (1 << 0)
> +#define ETM_SET_OPT_TS (1 << 1)
> +#define ETM_SET_OPT_MASK (ETM_SET_OPT_CTXTID | ETM_SET_OPT_TS)
> +

I would much rather see this fixed with the BIT() macro as it is done in the
rest of this set than defining new constant.

With the above:

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>

I have picked up the kernel portion of this set. I suggest you fix the above
and send another revision to Arnaldo with my RBs.

> static int cs_etm_set_option(struct auxtrace_record *itr,
> struct evsel *evsel, u32 option)
> {
> @@ -169,17 +173,17 @@ static int cs_etm_set_option(struct auxtrace_record *itr,
> !cpu_map__has(online_cpus, i))
> continue;
>
> - if (option & ETM_OPT_CTXTID) {
> + if (option & ETM_SET_OPT_CTXTID) {
> err = cs_etm_set_context_id(itr, evsel, i);
> if (err)
> goto out;
> }
> - if (option & ETM_OPT_TS) {
> + if (option & ETM_SET_OPT_TS) {
> err = cs_etm_set_timestamp(itr, evsel, i);
> if (err)
> goto out;
> }
> - if (option & ~(ETM_OPT_CTXTID | ETM_OPT_TS))
> + if (option & ~(ETM_SET_OPT_MASK))
> /* Nothing else is currently supported */
> goto out;
> }
> @@ -406,7 +410,7 @@ static int cs_etm_recording_options(struct auxtrace_record *itr,
> evsel__set_sample_bit(cs_etm_evsel, CPU);
>
> err = cs_etm_set_option(itr, cs_etm_evsel,
> - ETM_OPT_CTXTID | ETM_OPT_TS);
> + ETM_SET_OPT_CTXTID | ETM_SET_OPT_TS);
> if (err)
> goto out;
> }
> --
> 2.25.1