Re: [RFC V3 1/3] perf, tools: Support wildcards on pmu name in dynamic pmu events

From: Arnaldo Carvalho de Melo
Date: Wed Mar 07 2018 - 11:02:37 EST

Em Tue, Mar 06, 2018 at 09:04:42AM -0500, Agustin Vega-Frias escreveu:
> Starting on v4.12 event parsing code for dynamic pmu events already
> supports prefix-based matching of multiple pmus when creating dynamic
> events. E.g., in a system with the following dynamic pmus:
>
> mypmu_0
> mypmu_1
> mypmu_2
> mypmu_4
>
> passing mypmu/<config>/ as an event spec will result in the creation
> of the event in all of the pmus. This change expands this matching
> through the use of fnmatch so glob-like expressions can be used to
> create events in multiple pmus. E.g., in the system described above
> if a user only wants to create the event in mypmu_0 and mypmu_1,
> mypmu_[01]/<config>/ can be passed.
>
> Change-Id: Icb25653fc5d5239c20f3bffdfdf4ab4c9c9bb20b
> Signed-off-by: Agustin Vega-Frias <agustinv@xxxxxxxxxxxxxx>
> ---
> tools/perf/Documentation/perf-list.txt | 8 +++++++-
> tools/perf/Documentation/perf-stat.txt | 13 +++++++++++++
> tools/perf/util/parse-events.l | 2 +-
> tools/perf/util/parse-events.y | 19 ++++++++++++-------
> 4 files changed, 33 insertions(+), 9 deletions(-)
>
> diff --git a/tools/perf/Documentation/perf-list.txt b/tools/perf/Documentation/perf-list.txt
> index e2a897a..2549c34 100644
> --- a/tools/perf/Documentation/perf-list.txt
> +++ b/tools/perf/Documentation/perf-list.txt
> @@ -141,7 +141,13 @@ on the first memory controller on socket 0 of a Intel Xeon system
>
> Each memory controller has its own PMU. Measuring the complete system
> bandwidth would require specifying all imc PMUs (see perf list output),
> -and adding the values together.
> +and adding the values together. To simplify creation of multiple events,
> +prefix and glob matching is supported in the PMU name, and the prefix
> +'uncore_' is also ignored when performing the match. So the command above
> +can be expanded to all memory controllers by using the syntaxes:
> +
> + perf stat -C 0 -a imc/cas_count_read/,imc/cas_count_write/ -I 1000 ...
> + perf stat -C 0 -a *imc*/cas_count_read/,*imc*/cas_count_write/ -I 1000 ...
>
> This example measures the combined core power every second
>
> diff --git a/tools/perf/Documentation/perf-stat.txt b/tools/perf/Documentation/perf-stat.txt
> index 823fce7..5ee954f 100644
> --- a/tools/perf/Documentation/perf-stat.txt
> +++ b/tools/perf/Documentation/perf-stat.txt
> @@ -49,6 +49,13 @@ report::
> parameters are defined by corresponding entries in
> /sys/bus/event_source/devices/<pmu>/format/*
>
> + Note that the last two syntaxes support prefix and glob matching in
> + the PMU name to simplify creation of events accross multiple instances
> + of the same type of PMU in large systems (e.g. memory controller PMUs).
> + Multiple PMU instances are typical for uncore PMUs, so the prefix
> + 'uncore_' is also ignored when performing this match.
> +
> +
> -i::
> --no-inherit::
> child tasks do not inherit counters
> @@ -246,6 +253,12 @@ taskset.
> --no-merge::
> Do not merge results from same PMUs.
>
> +When multiple events are created from a single event alias, stat will,
> +by default, aggregate the event counts and show the result in a single
> +row. This option disables that behavior and shows the individual events
> +and counts. Aliases are listed immediately after the Kernel PMU events
> +by perf list.
> +
> --smi-cost::
> Measure SMI cost if msr/aperf/ and msr/smi/ events are supported.
>
> diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
> index 655ecff..a1a01b1 100644
> --- a/tools/perf/util/parse-events.l
> +++ b/tools/perf/util/parse-events.l
> @@ -175,7 +175,7 @@ bpf_source [^,{}]+\.c[a-zA-Z0-9._]*
> num_dec [0-9]+
> num_hex 0x[a-fA-F0-9]+
> num_raw_hex [a-fA-F0-9]+
> -name [a-zA-Z_*?][a-zA-Z0-9_*?.]*
> +name [a-zA-Z_*?\[\]][a-zA-Z0-9_*?.\[\]]*
> name_minus [a-zA-Z_*?][a-zA-Z0-9\-_*?.:]*
> drv_cfg_term [a-zA-Z0-9_\.]+(=[a-zA-Z0-9_*?\.:]+)?
> /* If you add a modifier you need to update check_modifier() */
> diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
> index e81a20e..316ac07 100644
> --- a/tools/perf/util/parse-events.y
> +++ b/tools/perf/util/parse-events.y
> @@ -8,6 +8,7 @@
>
> #define YYDEBUG 1
>
> +#include <fnmatch.h>
> #include <linux/compiler.h>
> #include <linux/list.h>
> #include <linux/types.h>
> @@ -234,21 +235,25 @@ PE_NAME opt_event_config
> if (parse_events_add_pmu(_parse_state, list, $1, $2)) {
> struct perf_pmu *pmu = NULL;
> int ok = 0;
> + char *pattern;
>
> - while ((pmu = perf_pmu__scan(pmu)) != NULL) {
> - char *name = pmu->name;
> + if (asprintf(&pattern, "?(uncore_)%s*", $1) < 0)
> + YYABORT;
>
> - if (!strncmp(name, "uncore_", 7) &&
> - strncmp($1, "uncore_", 7))
> - name += 7;
> - if (!strncmp($1, name, strlen($1))) {
> - if (parse_events_copy_term_list(orig_terms, &terms))
> + while ((pmu = perf_pmu__scan(pmu)) != NULL) {
> + if (!fnmatch(pattern, pmu->name, FNM_EXTMATCH)) {
> + if (parse_events_copy_term_list(orig_terms, &terms)) {
> + free(pattern);

This breaks the build in at least Alpine Linux 3.4, 3.5 and 3.6 and android-ndk:r15c-arm

Alpine 3.6 build failure:

CC /tmp/build/perf/util/parse-events-bison.o
util/parse-events.y: In function 'parse_events_parse':
util/parse-events.y:244:37: error: 'FNM_EXTMATCH' undeclared (first use in this function)
if (!fnmatch(pattern, pmu->name, FNM_EXTMATCH)) {
^~~~~~~~~~~~
util/parse-events.y:244:37: note: each undeclared identifier is reported only once for each function it appears in
CC /tmp/build/perf/bench/mem-functions.o
mv: can't rename '/tmp/build/perf/util/.parse-events-bison.o.tmp': No such file or directory
make[4]: *** [/git/linux/tools/build/Makefile.build:96: /tmp/build/perf/util/parse-events-bison.o] Error 1
make[3]: *** [/git/linux/tools/build/Makefile.build:139: util] Error 2
make[2]: *** [Makefile.perf:623: /tmp/build/perf/libperf-in.o] Error 2
make[2]: *** Waiting for unfinished jobs....

Android NDK r15c ARM, cross built from, IIRC, Fedora 24:

CC /tmp/build/perf/util/parse-events-bison.o
util/parse-events.y: In function 'parse_events_parse':
util/parse-events.y:244:37: error: 'FNM_EXTMATCH' undeclared (first use in this function)
if (!fnmatch(pattern, pmu->name, FNM_EXTMATCH)) {
^
util/parse-events.y:244:37: note: each undeclared identifier is reported only once for each function it appears in
mv: cannot stat '/tmp/build/perf/util/.parse-events-bison.o.tmp': No such file or directory
make[4]: *** [/git/linux/tools/build/Makefile.build:96: /tmp/build/perf/util/parse-events-bison.o] Error 1
make[4]: *** Waiting for unfinished jobs....
CC /tmp/build/perf/builtin-kmem.o
make[3]: *** [/git/linux/tools/build/Makefile.build:139: util] Error 2
make[2]: *** [Makefile.perf:623: /tmp/build/perf/libperf-in.o] Error 2


Probably others, I'll investigate later, feel free to do it if you have
the time now :-)

Extra info:


1 46.29 alpine:3.4 : FAIL gcc (Alpine 5.3.0) 5.3.0
2 53.37 alpine:3.5 : FAIL gcc (Alpine 6.2.1) 6.2.1 20160822
3 48.42 alpine:3.6 : FAIL gcc (Alpine 6.3.0) 6.3.0
4 35.88 alpine:edge : FAIL gcc (Alpine 6.4.0) 6.4.0
5 96.79 amazonlinux:1 : Ok gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-11)
6 116.40 amazonlinux:2 : Ok gcc (GCC) 7.2.1 20170915 (Red Hat 7.2.1-2)
7 34.30 android-ndk:r12b-arm : FAIL arm-linux-androideabi-gcc (GCC) 4.9.x 20150123 (prerelease)
8 33.69 android-ndk:r15c-arm : FAIL arm-linux-androideabi-gcc (GCC) 4.9.x 20150123 (prerelease)
9 60.50 centos:5 : Ok gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-55)
10 88.54 centos:6 : Ok gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-18)
11 108.89 centos:7 : Ok gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-16)


The builds are still ongoing.

- Arnaldo