Re: [PATCH 2/3] perf tools: Allow to enable/disable events via control file

[Arnaldo Carvalho de Melo]

Em Thu, Dec 10, 2020 at 02:15:03PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Thu, Dec 10, 2020 at 05:24:30PM +0100, Jiri Olsa escreveu:
> > On Mon, Dec 07, 2020 at 08:02:20PM +0300, Alexei Budankov wrote:
> > > On 06.12.2020 20:05, Jiri Olsa wrote:
> > > > @@ -1952,6 +1958,8 @@ int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd)
> > > >  	char cmd_data[EVLIST_CTL_CMD_MAX_LEN];
> > > >  	int ctlfd_pos = evlist->ctl_fd.pos;
> > > >  	struct pollfd *entries = evlist->core.pollfd.entries;
> > > > +	struct evsel *evsel;
> > > > +	char *evsel_name;
> > > >  
> > > >  	if (!evlist__ctlfd_initialized(evlist) || !entries[ctlfd_pos].revents)
> > > >  		return 0;
> > > > @@ -1967,6 +1975,26 @@ int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd)
> > > >  			case EVLIST_CTL_CMD_DISABLE:
> > > >  				evlist__disable(evlist);
> > > >  				break;
> > > > +			case EVLIST_CTL_CMD_ENABLE_EVSEL:
> > > > +				evsel_name = cmd_data + sizeof(EVLIST_CTL_CMD_ENABLE_EVSEL_TAG) - 1;

> > > It makes sense to check that evsel_name still points
> > > into cmd_data buffer after assigning to event name.

> > right, will add that

> So, I'm finishing test builds, so probably I'll push the first two
> patches publicly and then you can send a patch on top of this, ok?

> Unless the tests break somewhere and then I'll have to restart, so I'll
> fold in whatever gets at that time...

That was quick:

[perfbuilder@five ~]$ time dm
Thu Dec 10 01:44:52 PM -03 2020
# export PERF_TARBALL=http://192.168.86.5/perf/perf-5.10.0-rc6.tar.xz
# dm
   1    78.47 alpine:3.4                    : Ok   gcc (Alpine 5.3.0) 5.3.0, clang version 3.8.0 (tags/RELEASE_380/final)
   2   104.38 alpine:3.5                    : Ok   gcc (Alpine 6.2.1) 6.2.1 20160822, clang version 3.8.1 (tags/RELEASE_381/final)
   3   105.64 alpine:3.6                    : Ok   gcc (Alpine 6.3.0) 6.3.0, clang version 4.0.0 (tags/RELEASE_400/final)
   4    96.52 alpine:3.7                    : Ok   gcc (Alpine 6.4.0) 6.4.0, Alpine clang version 5.0.0 (tags/RELEASE_500/final) (based on LLVM 5.0.0)
   5    81.08 alpine:3.8                    : Ok   gcc (Alpine 6.4.0) 6.4.0, Alpine clang version 5.0.1 (tags/RELEASE_501/final) (based on LLVM 5.0.1)
   6    85.20 alpine:3.9                    : Ok   gcc (Alpine 8.3.0) 8.3.0, Alpine clang version 5.0.1 (tags/RELEASE_502/final) (based on LLVM 5.0.1)
   7   106.10 alpine:3.10                   : Ok   gcc (Alpine 8.3.0) 8.3.0, Alpine clang version 8.0.0 (tags/RELEASE_800/final) (based on LLVM 8.0.0)
   8   120.20 alpine:3.11                   : Ok   gcc (Alpine 9.3.0) 9.3.0, Alpine clang version 9.0.0 (https://git.alpinelinux.org/aports f7f0d2c2b8bcd6a5843401a9a702029556492689) (based on LLVM 9.0.0)
   9   109.99 alpine:3.12                   : Ok   gcc (Alpine 9.3.0) 9.3.0, Alpine clang version 10.0.0 (https://gitlab.alpinelinux.org/alpine/aports.git 7445adce501f8473efdb93b17b5eaf2f1445ed4c)
  10   117.76 alpine:edge                   : Ok   gcc (Alpine 10.2.0) 10.2.0, Alpine clang version 10.0.1
  11    69.15 alt:p8                        : Ok   x86_64-alt-linux-gcc (GCC) 5.3.1 20151207 (ALT p8 5.3.1-alt3.M80P.1), clang version 3.8.0 (tags/RELEASE_380/final)
  12    84.55 alt:p9                        : Ok   x86_64-alt-linux-gcc (GCC) 8.4.1 20200305 (ALT p9 8.4.1-alt0.p9.1), clang version 10.0.0
  13    82.69 alt:sisyphus                  : Ok   x86_64-alt-linux-gcc (GCC) 9.3.1 20200518 (ALT Sisyphus 9.3.1-alt1), clang version 10.0.1
  14    66.22 amazonlinux:1                 : Ok   gcc (GCC) 7.2.1 20170915 (Red Hat 7.2.1-2), clang version 3.6.2 (tags/RELEASE_362/final)
  15   100.16 amazonlinux:2                 : Ok   gcc (GCC) 7.3.1 20180712 (Red Hat 7.3.1-9), clang version 7.0.1 (Amazon Linux 2 7.0.1-1.amzn2.0.2)
  16    11.20 android-ndk:r12b-arm          : FAIL arm-linux-androideabi-gcc (GCC) 4.9.x 20150123 (prerelease)
  17    11.90 android-ndk:r15c-arm          : FAIL arm-linux-androideabi-gcc (GCC) 4.9.x 20150123 (prerelease)
  18    26.33 centos:6                      : Ok   gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-23)
  19    31.80 centos:7                      : Ok   gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-44)
  20   116.02 centos:8                      : Ok   gcc (GCC) 8.3.1 20191121 (Red Hat 8.3.1-5), clang version 9.0.1 (Red Hat 9.0.1-2.module_el8.2.0+309+0c7b6b03)
  21    62.27 clearlinux:latest             : Ok   gcc (Clear Linux OS for Intel Architecture) 10.2.1 20201106 releases/gcc-10.2.0-475-g099857318c, clang version 10.0.1
  22    77.82 debian:8                      : Ok   gcc (Debian 4.9.2-10+deb8u2) 4.9.2, Debian clang version 3.5.0-10 (tags/RELEASE_350/final) (based on LLVM 3.5.0)
  23: debian:9


There I go...

[perfbuilder@five ~]$ tail -20 dm.log/android-ndk\:r12b-arm
  FLEX     /tmp/build/perf/util/expr-flex.c
  CC       /tmp/build/perf/util/pmu-bison.o
  CC       /tmp/build/perf/util/expr-bison.o
  CC       /tmp/build/perf/util/expr-flex.o
  CC       /tmp/build/perf/util/expr.o
  CC       /tmp/build/perf/util/parse-events.o
  CC       /tmp/build/perf/util/parse-events-flex.o
  CC       /tmp/build/perf/util/pmu.o
  CC       /tmp/build/perf/util/pmu-flex.o
  LD       /tmp/build/perf/util/intel-pt-decoder/perf-in.o
  LD       /tmp/build/perf/util/perf-in.o
  LD       /tmp/build/perf/perf-in.o
  LINK     /tmp/build/perf/perf
/tmp/build/perf/perf-in.o:hist.c:function pmu_for_each_sys_event: error: undefined reference to 'pmu_sys_event_tables'
collect2: error: ld returned 1 exit status
make[2]: *** [Makefile.perf:659: /tmp/build/perf/perf] Error 1
make[1]: *** [Makefile.perf:233: sub-make] Error 2
make: *** [Makefile:70: all] Error 2
make: Leaving directory '/git/linux/tools/perf'
+ exit 1
[perfbuilder@five ~]

Now to figure out who generates this pmu_sys_event_tables, John?

- Arnaldo