lkml.org 
[lkml]   [2019]   [Jun]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2 2/5] perf pmu: Support more complex PMU event aliasing
On Fri, Jun 14, 2019 at 10:08:00PM +0800, John Garry wrote:
> The jevent "Unit" field is used for uncore PMU alias definition.
>
> The form uncore_pmu_example_X is supported, where "X" is a wildcard,
> to support multiple instances of the same PMU in a system.
>
> Unfortunately this format not suitable for all uncore PMUs; take the Hisi
> DDRC uncore PMU for example, where the name is in the form
> hisi_scclX_ddrcY.
>
> For the current jevent parsing, we would be required to hardcode an uncore
> alias translation for each possible value of X. This is not scalable.
>
> Instead, add support for "Unit" field in the form "hisi_sccl,ddrc", where
> we can match by hisi_scclX and ddrcY. Tokens in Unit field are
> delimited by ','.
>
> Signed-off-by: John Garry <john.garry@huawei.com>
> ---
> tools/perf/util/pmu.c | 39 ++++++++++++++++++++++++++++++++++-----
> 1 file changed, 34 insertions(+), 5 deletions(-)
>
> diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
> index 7e7299fee550..bc71c60589b5 100644
> --- a/tools/perf/util/pmu.c
> +++ b/tools/perf/util/pmu.c
> @@ -700,6 +700,39 @@ struct pmu_events_map *perf_pmu__find_map(struct perf_pmu *pmu)
> return map;
> }
>
> +static bool pmu_uncore_alias_match(const char *pmu_name, const char *name)
> +{
> + char *tmp, *tok, *str;
> + bool res;
> +
> + str = strdup(pmu_name);
> + if (!str)
> + return false;
> +
> + /*
> + * uncore alias may be from different PMU with common
> + * prefix or matching tokens.
> + */
> + tok = strtok_r(str, ",", &tmp);
> + if (strncmp(pmu_name, tok, strlen(tok))) {

if tok is NULL in here we crash

> + res = false;
> + goto out;
> + }
> +
> + for (; tok; name += strlen(tok), tok = strtok_r(NULL, ",", &tmp)) {

why is name shifted in here?

jirka

> + name = strstr(name, tok);
> + if (!name) {
> + res = false;
> + goto out;
> + }
> + }
> +
> + res = true;
> +out:
> + free(str);
> + return res;
> +}
> +
> /*
> * From the pmu_events_map, find the table of PMU events that corresponds
> * to the current running CPU. Then, add all PMU events from that table
> @@ -730,12 +763,8 @@ static void pmu_add_cpu_aliases(struct list_head *head, struct perf_pmu *pmu)
> break;
> }
>
> - /*
> - * uncore alias may be from different PMU
> - * with common prefix
> - */
> if (pmu_is_uncore(name) &&
> - !strncmp(pname, name, strlen(pname)))
> + pmu_uncore_alias_match(pname, name))
> goto new_alias;
>
> if (strcmp(pname, name))
> --
> 2.17.1
>

\
 
 \ /
  Last update: 2019-06-16 11:59    [W:0.132 / U:1.460 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site