2020-02-21 23:21:07

by Jiri Olsa

Subject: [RFC 0/4] perf expr: Add flex scanner

hi,
while preparing changes for user defined metric expressions
I also moved the expression manual parser to flex.

The reason is to have an easy and reasonable way to support
and parse multiple user-defined metric expressions from
command line or file.

I was posponing the change, but I just saw another update to
the expr manual scanner (from Kajol Jain), so cherry picked
just the expr flex code changes to get it out.

Kajol Jain,
I think it should ease up your change for unknown values marked
by '?'. Would you consider rebasing your changes on top of this?


Available also in:
git://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
perf/metric_flex

thanks,
jirka


---
Jiri Olsa (4):
perf expr: Add expr.c object
perf expr: Move expr lexer to flex
perf expr: Increase EXPR_MAX_OTHER
perf expr: Straighten expr__parse/expr__find_other interface

tools/perf/tests/expr.c | 6 ++--
tools/perf/util/Build | 11 +++++++-
tools/perf/util/expr.c | 111 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
tools/perf/util/expr.h | 8 ++----
tools/perf/util/expr.l | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
tools/perf/util/expr.y | 185 +++++++++++++++++++++----------------------------------------------------------------------------------------------------
tools/perf/util/stat-shadow.c | 4 +--
7 files changed, 242 insertions(+), 166 deletions(-)
create mode 100644 tools/perf/util/expr.c
create mode 100644 tools/perf/util/expr.l

2020-02-21 23:22:08

by Jiri Olsa

Subject: [PATCH 4/4] perf expr: Straighten expr__parse/expr__find_other interface

Now with flex parser we don't need to update parsed string
pointer, so the interface can just passed the pointer to the
expression instead of pointer to pointer.

Signed-off-by: Jiri Olsa <[email protected]>
---
tools/perf/tests/expr.c | 6 +++---
tools/perf/util/expr.c | 8 ++++----
tools/perf/util/expr.h | 4 ++--
tools/perf/util/stat-shadow.c | 4 +---
4 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/tools/perf/tests/expr.c b/tools/perf/tests/expr.c
index 87843af4c118..755d73c86c68 100644
--- a/tools/perf/tests/expr.c
+++ b/tools/perf/tests/expr.c
@@ -10,7 +10,7 @@ static int test(struct parse_ctx *ctx, const char *e, double val2)
{
double val;

- if (expr__parse(&val, ctx, &e))
+ if (expr__parse(&val, ctx, e))
TEST_ASSERT_VAL("parse test failed", 0);
TEST_ASSERT_VAL("unexpected value", val == val2);
return 0;
@@ -44,11 +44,11 @@ int test__expr(struct test *t __maybe_unused, int subtest __maybe_unused)
return ret;

p = "FOO/0";
- ret = expr__parse(&val, &ctx, &p);
+ ret = expr__parse(&val, &ctx, p);
TEST_ASSERT_VAL("division by zero", ret == 1);

p = "BAR/";
- ret = expr__parse(&val, &ctx, &p);
+ ret = expr__parse(&val, &ctx, p);
TEST_ASSERT_VAL("missing operand", ret == 1);

TEST_ASSERT_VAL("find other",
diff --git a/tools/perf/util/expr.c b/tools/perf/util/expr.c
index b15cfa7ba694..6bd1e93a12b5 100644
--- a/tools/perf/util/expr.c
+++ b/tools/perf/util/expr.c
@@ -52,9 +52,9 @@ __expr__parse(double *val, struct parse_ctx *ctx, const char *expr,
return ret;
}

-int expr__parse(double *final_val, struct parse_ctx *ctx, const char **pp)
+int expr__parse(double *final_val, struct parse_ctx *ctx, const char *expr)
{
- return __expr__parse(final_val, ctx, *pp, EXPR_PARSE);
+ return __expr__parse(final_val, ctx, expr, EXPR_PARSE);
}

static bool
@@ -71,14 +71,14 @@ already_seen(const char *val, const char *one, const char **other,
return false;
}

-int expr__find_other(const char *p, const char *one, const char ***other,
+int expr__find_other(const char *expr, const char *one, const char ***other,
int *num_other)
{
int err, i = 0, j = 0;
struct parse_ctx ctx;

expr__ctx_init(&ctx);
- err = __expr__parse(NULL, &ctx, p, EXPR_OTHER);
+ err = __expr__parse(NULL, &ctx, expr, EXPR_OTHER);
if (err)
return err;

diff --git a/tools/perf/util/expr.h b/tools/perf/util/expr.h
index 01e1529bdfd9..28a0a2dfbd8c 100644
--- a/tools/perf/util/expr.h
+++ b/tools/perf/util/expr.h
@@ -17,8 +17,8 @@ struct parse_ctx {

void expr__ctx_init(struct parse_ctx *ctx);
void expr__add_id(struct parse_ctx *ctx, const char *id, double val);
-int expr__parse(double *final_val, struct parse_ctx *ctx, const char **pp);
-int expr__find_other(const char *p, const char *one, const char ***other,
+int expr__parse(double *final_val, struct parse_ctx *ctx, const char *expr);
+int expr__find_other(const char *expr, const char *one, const char ***other,
int *num_other);

#endif
diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
index 2c41d47f6f83..854d6abf2993 100644
--- a/tools/perf/util/stat-shadow.c
+++ b/tools/perf/util/stat-shadow.c
@@ -779,9 +779,7 @@ static void generic_metric(struct perf_stat_config *config,
}

if (!metric_events[i]) {
- const char *p = metric_expr;
-
- if (expr__parse(&ratio, &pctx, &p) == 0) {
+ if (expr__parse(&ratio, &pctx, metric_expr) == 0) {
char *unit;
char metric_bf[64];

--
2.24.1