[PATCH 4/4] perf expr: Report line number with error

From: Jiri Olsa
Date: Mon May 11 2020 - 16:53:35 EST


Display line number on when parsing custom metrics file, like:

$ cat metrics
// IPC
mine1 = inst_retired.any / cpu_clk_unhalted.thread;

krava
$ sudo perf stat --metrics-file ./metrics -M mine1 -a -I 1000 --metric-only
failed to parse metrics file: ./metrics:4

Please note that because the grammar is flexible on new lines,
the syntax could be broken on the next 'not fitting' item and
not the first wrong word, like:

$ cat metrics
// IPC
krava
mine1 = inst_retired.any / cpu_clk_unhalted.thread;
$ sudo perf stat --metrics-file ./metrics -M mine1 -a -I 1000 --metric-only
failed to parse metrics file: ./metrics:3

Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
tools/perf/tests/expr.c | 5 +++++
tools/perf/util/expr.h | 2 ++
tools/perf/util/expr.l | 10 ++++++++++
tools/perf/util/expr.y | 8 +++++---
tools/perf/util/metricgroup.c | 3 ++-
5 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/tools/perf/tests/expr.c b/tools/perf/tests/expr.c
index c62e122fe719..3bffcd9f8397 100644
--- a/tools/perf/tests/expr.c
+++ b/tools/perf/tests/expr.c
@@ -84,5 +84,10 @@ int test__expr(struct test *t __maybe_unused, int subtest __maybe_unused)
zfree(&ctx.custom[i].name);
zfree(&ctx.custom[i].expr);
}
+
+ expr__ctx_init(&ctx);
+ ret = expr__parse_custom(&ctx, "IPC=INSTRUCTIONS / CYCLES;\n error");
+ TEST_ASSERT_VAL("parse custom failed", ret != 0);
+ TEST_ASSERT_VAL("parse custom count", ctx.lineno == 2);
return 0;
}
diff --git a/tools/perf/util/expr.h b/tools/perf/util/expr.h
index ef116b58a5d4..ce95dfd2ad5a 100644
--- a/tools/perf/util/expr.h
+++ b/tools/perf/util/expr.h
@@ -27,6 +27,8 @@ struct expr_parse_ctx {
struct expr_parse_custom custom[EXPR_MAX];
};
};
+ /* Set on error for custom metrics. */
+ int lineno;
};

struct expr_scanner_ctx {
diff --git a/tools/perf/util/expr.l b/tools/perf/util/expr.l
index e9b294ba09fc..718aac4316d7 100644
--- a/tools/perf/util/expr.l
+++ b/tools/perf/util/expr.l
@@ -1,6 +1,8 @@
%option prefix="expr_"
%option reentrant
%option bison-bridge
+%option bison-locations
+%option yylineno

%{
#include <linux/compiler.h>
@@ -79,6 +81,13 @@ static int str(yyscan_t scanner, int token, int runtime)
yylval->str = normalize(yylval->str, runtime);
return token;
}
+
+#define YY_USER_ACTION \
+do { \
+ yylloc->last_line = yylloc->first_line; \
+ yylloc->first_line = yylineno; \
+} while (0);
+
%}

%x custom
@@ -101,6 +110,7 @@ all [^;]+

if (sctx->start_token) {
sctx->start_token = 0;
+ yylineno = 1;
return start_token;
}
}
diff --git a/tools/perf/util/expr.y b/tools/perf/util/expr.y
index 0521e48fa5e3..812d893bcd31 100644
--- a/tools/perf/util/expr.y
+++ b/tools/perf/util/expr.y
@@ -18,6 +18,7 @@
%parse-param { struct expr_parse_ctx *ctx }
%parse-param {void *scanner}
%lex-param {void* scanner}
+%locations

%union {
double num;
@@ -39,12 +40,13 @@
%type <num> expr if_expr

%{
-static void expr_error(double *final_val __maybe_unused,
- struct expr_parse_ctx *ctx __maybe_unused,
+static void expr_error(YYLTYPE *loc, double *final_val __maybe_unused,
+ struct expr_parse_ctx *ctx,
void *scanner,
const char *s)
{
- pr_debug("%s\n", s);
+ pr_debug("%s, line %d\n", s, loc->last_line);
+ ctx->lineno = loc->last_line;
}

static int lookup_id(struct expr_parse_ctx *ctx, char *id, double *val)
diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
index 3b4d5bdb5ac6..36df43546e84 100644
--- a/tools/perf/util/metricgroup.c
+++ b/tools/perf/util/metricgroup.c
@@ -615,7 +615,8 @@ static int metricgroup__add_metric_list(const char *list, struct strbuf *events,
ret = expr__parse_custom(&ctx, buf);
free(buf);
if (ret) {
- pr_err("failed to parse metrics file: %s\n", metrics_file);
+ pr_err("failed to parse metrics file: %s:%d\n",
+ metrics_file, ctx.lineno);
return -1;
}
}
--
2.25.4