On Wed, Aug 12, 2020 at 08:27:08AM -0300, Arnaldo Carvalho de Melo wrote: > Em Wed, Jul 22, 2020 at 11:20:53AM +0200, Thomas Richter escreveu: > > Fix a compile error on F32 and gcc version 10.1 on s390 in file > > utils/stat-display.c. The error does not show up with make DEBUG=y. > > In fact the issue shows up when using both compiler options > > -O6 and -D_FORTIFY_SOURCE=2 (which are omitted with DEBUG=Y). > > > > This is the offending call chain: > > print_counter_aggr() > > printout(config, -1, 0, ...) with 2nd parm id set to -1 > > aggr_printout(config, x, id --> -1, ...) which leads to this code: > > case AGGR_NONE: > > if (evsel->percore && !config->percore_show_thread) { > > .... > > } else { > > fprintf(config->output, "CPU%*d%s", > > config->csv_output ? 0 : -7, > > evsel__cpus(evsel)->map[id], > > ^^ id is -1 !!!! > > config->csv_sep); > > } > > > > This is a compiler inlining issue which is detected on s390 but not on > > other plattforms. > > What is the sequence of events that gets to this? I.e. is it valid to > get a config->aggr_mode == AGGR_NONE, then have evsel not be percore and > config->percore_show_thread to be false? > > I wonder if this won't be papering over some bug :-\ > > Jin? > > This is where this came from: > commit 4fc4d8dfa056dfd48afe73b9ea3b7570ceb80b9c (tag: > perf-core-for-mingo-5.2-20190517) > Author: Jin Yao <yao....@linux.intel.com> > Date: Fri Apr 12 21:59:49 2019 +0800 > > perf stat: Support 'percore' event qualifier > > With this patch, we can use the 'percore' event qualifier in perf-stat. > > --- > > Also please add at least Jiri and Namhyung on the CC list, having the > person that added that array usage also helps. > > [acme@quaco perf]$ scripts/get_maintainer.pl tools/perf | grep reviewer > Mark Rutland <mark.rutl...@arm.com> (reviewer:PERFORMANCE EVENTS SUBSYSTEM) > Alexander Shishkin <alexander.shish...@linux.intel.com> (reviewer:PERFORMANCE > EVENTS SUBSYSTEM) > Jiri Olsa <jo...@redhat.com> (reviewer:PERFORMANCE EVENTS SUBSYSTEM) > Namhyung Kim <namhy...@kernel.org> (reviewer:PERFORMANCE EVENTS SUBSYSTEM) > [acme@quaco perf]$ > > Thanks, > > - Arnaldo > > > Output before: > > # make util/stat-display.o > > ..... > > > > util/stat-display.c: In function ‘perf_evlist__print_counters’: > > util/stat-display.c:121:4: error: array subscript -1 is below array > > bounds of ‘int[]’ [-Werror=array-bounds] > > 121 | fprintf(config->output, "CPU%*d%s", > > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > 122 | config->csv_output ? 0 : -7, > > | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > 123 | evsel__cpus(evsel)->map[id], > > | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > 124 | config->csv_sep); > > | ~~~~~~~~~~~~~~~~ > > In file included from util/evsel.h:13, > > from util/evlist.h:13, > > from util/stat-display.c:9: > > /root/linux/tools/lib/perf/include/internal/cpumap.h:10:7: > > note: while referencing ‘map’ > > 10 | int map[]; > > | ^~~ > > cc1: all warnings being treated as errors > > mv: cannot stat 'util/.stat-display.o.tmp': No such file or directory > > make[3]: *** [/root/linux/tools/build/Makefile.build:97: > > util/stat-display.o] > > Error 1 > > make[2]: *** [Makefile.perf:716: util/stat-display.o] Error 2 > > make[1]: *** [Makefile.perf:231: sub-make] Error 2 > > make: *** [Makefile:110: util/stat-display.o] Error 2 > > [root@t35lp46 perf]#
I tested on s390 with rhel8, but did not get this error, f32's gcc must be smarter > > > > Output after: > > # make util/stat-display.o > > ..... > > CC util/stat-display.o > > [root@t35lp46 perf]# > > > > Signed-off-by: Thomas Richter <tmri...@linux.ibm.com> > > --- > > tools/perf/util/stat-display.c | 9 +++++---- > > 1 file changed, 5 insertions(+), 4 deletions(-) > > > > diff --git a/tools/perf/util/stat-display.c b/tools/perf/util/stat-display.c > > index 57d0706e1330..e49e544188e4 100644 > > --- a/tools/perf/util/stat-display.c > > +++ b/tools/perf/util/stat-display.c > > @@ -118,10 +118,11 @@ static void aggr_printout(struct perf_stat_config > > *config, > > config->csv_output ? 0 : -3, > > cpu_map__id_to_cpu(id), config->csv_sep); > > } else { > > - fprintf(config->output, "CPU%*d%s", > > - config->csv_output ? 0 : -7, > > - evsel__cpus(evsel)->map[id], > > - config->csv_sep); > > + if (id > -1) > > + fprintf(config->output, "CPU%*d%s", > > + config->csv_output ? 0 : -7, > > + evsel__cpus(evsel)->map[id], > > + config->csv_sep); -1 is only through print_counter_aggr which is called for AGGR_GLOBAL case as you described, but I guess we can have this check as precaution you could put it together with above else } else if (id > -1) thanks, jirka