aboutsummaryrefslogtreecommitdiffstats
path: root/tools/perf/util/expr.y
diff options
context:
space:
mode:
authorIan Rogers <irogers@google.com>2020-05-01 10:33:31 -0700
committerArnaldo Carvalho de Melo <acme@redhat.com>2020-05-28 10:03:25 -0300
commit9be27a5d416925aef4ff816379c31b8cd18ff55d (patch)
treed6393b081260de906b5e04f73276446b5039eecb /tools/perf/util/expr.y
parentperf metrics: Fix parse errors in power9 metrics (diff)
downloadlinux-dev-9be27a5d416925aef4ff816379c31b8cd18ff55d.tar.xz
linux-dev-9be27a5d416925aef4ff816379c31b8cd18ff55d.zip
perf expr: Print a debug message for division by zero
If an expression yields 0 and is then divided-by/modulus-by then the parsing aborts. Add a debug error message to better enable debugging when this happens. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Haiyan Song <haiyanx.song@intel.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: John Garry <john.garry@huawei.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Clarke <pc@us.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Cc: Song Liu <songliubraving@fb.com> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20200501173333.227162-11-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/expr.y')
-rw-r--r--tools/perf/util/expr.y14
1 files changed, 12 insertions, 2 deletions
diff --git a/tools/perf/util/expr.y b/tools/perf/util/expr.y
index 54260094b947..21e82a1e11a2 100644
--- a/tools/perf/util/expr.y
+++ b/tools/perf/util/expr.y
@@ -103,8 +103,18 @@ expr: NUMBER
| expr '+' expr { $$ = $1 + $3; }
| expr '-' expr { $$ = $1 - $3; }
| expr '*' expr { $$ = $1 * $3; }
- | expr '/' expr { if ($3 == 0) YYABORT; $$ = $1 / $3; }
- | expr '%' expr { if ((long)$3 == 0) YYABORT; $$ = (long)$1 % (long)$3; }
+ | expr '/' expr { if ($3 == 0) {
+ pr_debug("division by zero\n");
+ YYABORT;
+ }
+ $$ = $1 / $3;
+ }
+ | expr '%' expr { if ((long)$3 == 0) {
+ pr_debug("division by zero\n");
+ YYABORT;
+ }
+ $$ = (long)$1 % (long)$3;
+ }
| '-' expr %prec NEG { $$ = -$2; }
| '(' if_expr ')' { $$ = $2; }
| MIN '(' expr ',' expr ')' { $$ = $3 < $5 ? $3 : $5; }