Re: [PATCH v3] perf tools: Fix pattern matching for same substring in different pmu type

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Tue, Jul 06, 2021 at 04:02:24PM -0400, Liang, Kan escreveu:
> On 7/6/2021 3:44 PM, Jiri Olsa wrote:
> > On Thu, Jul 01, 2021 at 02:42:53PM +0800, Jin Yao wrote:
> > > Some different pmu types may have same substring. For example,
> > > on Icelake server, we have pmu types "uncore_imc" and
> > > "uncore_imc_free_running". Both pmu types have substring "uncore_imc".
> > > But the parser would wrongly think they are the same pmu type.

> > > We enable an imc event,
> > > perf stat -e uncore_imc/event=0xe3/ -a -- sleep 1

> > > Perf actually expands the event to:
> > > uncore_imc_0/event=0xe3/
> > > uncore_imc_1/event=0xe3/
> > > uncore_imc_2/event=0xe3/
> > > uncore_imc_3/event=0xe3/
> > > uncore_imc_4/event=0xe3/
> > > uncore_imc_5/event=0xe3/
> > > uncore_imc_6/event=0xe3/
> > > uncore_imc_7/event=0xe3/
> > > uncore_imc_free_running_0/event=0xe3/
> > > uncore_imc_free_running_1/event=0xe3/
> > > uncore_imc_free_running_3/event=0xe3/
> > > uncore_imc_free_running_4/event=0xe3/

> > > That's because the "uncore_imc_free_running" matches the
> > > pattern "uncore_imc*".

> > > Now we check that the last characters of pmu name is
> > > '_<digit>'.
> > > 
> > > For example, for pattern "uncore_imc*", "uncore_imc_0" is parsed ok,
> > > but "uncore_imc_free_running_0" would be failed.
> > > 
> > > Fixes: b2b9d3a3f021 ("perf pmu: Support wildcards on pmu name in dynamic pmu events")
> > > Signed-off-by: Jin Yao <yao.jin@linux.intel.com>

> > looks good to me, Kan, Andi?

> Yes, it looks good to me too.

> Reviewed-by: Kan Liang <kan.liang@linux.intel.com>

Thanks, I'm applying it, Jin, please next time Cc the author of the
patch you're fixing, in this case:

  Cc: Agustin Vega-Frias <agustinv@codeaurora.org>

I'm adding it to this message as well.
 
> BTW: The new uncore patch[1] for the "alias" attribute should be easily
> rebase on this patch. I believe Yao has already finished the test as well. I
> think he will resend the new "alias" attribute patch later soon.
> [1] https://lore.kernel.org/lkml/1624990443-168533-7-git-send-email-kan.liang@linux.intel.com
> 
> Thanks,
> Kan
> 
> > 
> > Acked-by: Jiri Olsa <jolsa@redhat.com>
> > 
> > thanks,
> > jirka
> > 
> > > ---
> > >   tools/perf/util/parse-events.y |  2 +-
> > >   tools/perf/util/pmu.c          | 36 +++++++++++++++++++++++++++++++++-
> > >   tools/perf/util/pmu.h          |  1 +
> > >   3 files changed, 37 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
> > > index aba12a4d488e..9321bd0e2f76 100644
> > > --- a/tools/perf/util/parse-events.y
> > > +++ b/tools/perf/util/parse-events.y
> > > @@ -316,7 +316,7 @@ event_pmu_name opt_pmu_config
> > >   			if (!strncmp(name, "uncore_", 7) &&
> > >   			    strncmp($1, "uncore_", 7))
> > >   				name += 7;
> > > -			if (!fnmatch(pattern, name, 0)) {
> > > +			if (!perf_pmu__match(pattern, name, $1)) {
> > >   				if (parse_events_copy_term_list(orig_terms, &terms))
> > >   					CLEANUP_YYABORT;
> > >   				if (!parse_events_add_pmu(_parse_state, list, pmu->name, terms, true, false))
> > > diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
> > > index 88c8ecdc60b0..44b90d638ad5 100644
> > > --- a/tools/perf/util/pmu.c
> > > +++ b/tools/perf/util/pmu.c
> > > @@ -3,6 +3,7 @@
> > >   #include <linux/compiler.h>
> > >   #include <linux/string.h>
> > >   #include <linux/zalloc.h>
> > > +#include <linux/ctype.h>
> > >   #include <subcmd/pager.h>
> > >   #include <sys/types.h>
> > >   #include <errno.h>
> > > @@ -17,6 +18,7 @@
> > >   #include <locale.h>
> > >   #include <regex.h>
> > >   #include <perf/cpumap.h>
> > > +#include <fnmatch.h>
> > >   #include "debug.h"
> > >   #include "evsel.h"
> > >   #include "pmu.h"
> > > @@ -740,6 +742,27 @@ struct pmu_events_map *__weak pmu_events_map__find(void)
> > >   	return perf_pmu__find_map(NULL);
> > >   }
> > > +static bool perf_pmu__valid_suffix(char *pmu_name, char *tok)
> > > +{
> > > +	char *p;
> > > +
> > > +	if (strncmp(pmu_name, tok, strlen(tok)))
> > > +		return false;
> > > +
> > > +	p = pmu_name + strlen(tok);
> > > +	if (*p == 0)
> > > +		return true;
> > > +
> > > +	if (*p != '_')
> > > +		return false;
> > > +
> > > +	++p;
> > > +	if (*p == 0 || !isdigit(*p))
> > > +		return false;
> > > +
> > > +	return true;
> > > +}
> > > +
> > >   bool pmu_uncore_alias_match(const char *pmu_name, const char *name)
> > >   {
> > >   	char *tmp = NULL, *tok, *str;
> > > @@ -768,7 +791,7 @@ bool pmu_uncore_alias_match(const char *pmu_name, const char *name)
> > >   	 */
> > >   	for (; tok; name += strlen(tok), tok = strtok_r(NULL, ",", &tmp)) {
> > >   		name = strstr(name, tok);
> > > -		if (!name) {
> > > +		if (!name || !perf_pmu__valid_suffix((char *)name, tok)) {
> > >   			res = false;
> > >   			goto out;
> > >   		}
> > > @@ -1872,3 +1895,14 @@ bool perf_pmu__has_hybrid(void)
> > >   	return !list_empty(&perf_pmu__hybrid_pmus);
> > >   }
> > > +
> > > +int perf_pmu__match(char *pattern, char *name, char *tok)
> > > +{
> > > +	if (fnmatch(pattern, name, 0))
> > > +		return -1;
> > > +
> > > +	if (tok && !perf_pmu__valid_suffix(name, tok))
> > > +		return -1;
> > > +
> > > +	return 0;
> > > +}
> > > diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h
> > > index a790ef758171..926da483a141 100644
> > > --- a/tools/perf/util/pmu.h
> > > +++ b/tools/perf/util/pmu.h
> > > @@ -133,5 +133,6 @@ void perf_pmu__warn_invalid_config(struct perf_pmu *pmu, __u64 config,
> > >   				   char *name);
> > >   bool perf_pmu__has_hybrid(void);
> > > +int perf_pmu__match(char *pattern, char *name, char *tok);
> > >   #endif /* __PMU_H */
> > > -- 
> > > 2.17.1
> > > 
> > 

-- 

- Arnaldo