perf script: Add option to pass arguments to dlfilters

Add option --dlarg to pass arguments to dlfilters. The --dlarg option can
be repeated to pass more than 1 argument.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.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: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210627131818.810-5-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

3 files changed, 46 insertions, 9 deletions

diff --git a/tools/perf/util/dlfilter.c b/tools/perf/util/dlfilter.c
index 288a2b57378c..eaa3cea49178 100644
--- a/tools/perf/util/dlfilter.c
+++ b/tools/perf/util/dlfilter.c
@@ -133,9 +133,26 @@ static const struct perf_dlfilter_al *dlfilter__resolve_addr(void *ctx)
 	return d_addr_al;
 }
 
+static char **dlfilter__args(void *ctx, int *dlargc)
+{
+	struct dlfilter *d = (struct dlfilter *)ctx;
+
+	if (dlargc)
+		*dlargc = 0;
+	else
+		return NULL;
+
+	if (!d->ctx_valid && !d->in_start && !d->in_stop)
+		return NULL;
+
+	*dlargc = d->dlargc;
+	return d->dlargv;
+}
+
 static const struct perf_dlfilter_fns perf_dlfilter_fns = {
 	.resolve_ip      = dlfilter__resolve_ip,
 	.resolve_addr    = dlfilter__resolve_addr,
+	.args            = dlfilter__args,
 };
 
 static char *find_dlfilter(const char *file)
@@ -169,7 +186,7 @@ out:
 
 #define CHECK_FLAG(x) BUILD_BUG_ON((u64)PERF_DLFILTER_FLAG_ ## x != (u64)PERF_IP_FLAG_ ## x)
 
-static int dlfilter__init(struct dlfilter *d, const char *file)
+static int dlfilter__init(struct dlfilter *d, const char *file, int dlargc, char **dlargv)
 {
 	CHECK_FLAG(BRANCH);
 	CHECK_FLAG(CALL);
@@ -189,6 +206,8 @@ static int dlfilter__init(struct dlfilter *d, const char *file)
 	d->file = find_dlfilter(file);
 	if (!d->file)
 		return -1;
+	d->dlargc = dlargc;
+	d->dlargv = dlargv;
 	return 0;
 }
 
@@ -219,14 +238,14 @@ static int dlfilter__close(struct dlfilter *d)
 	return dlclose(d->handle);
 }
 
-struct dlfilter *dlfilter__new(const char *file)
+struct dlfilter *dlfilter__new(const char *file, int dlargc, char **dlargv)
 {
 	struct dlfilter *d = malloc(sizeof(*d));
 
 	if (!d)
 		return NULL;
 
-	if (dlfilter__init(d, file))
+	if (dlfilter__init(d, file, dlargc, dlargv))
 		goto err_free;
 
 	if (dlfilter__open(d))
@@ -253,16 +272,28 @@ int dlfilter__start(struct dlfilter *d, struct perf_session *session)
 {
 	if (d) {
 		d->session = session;
-		if (d->start)
-			return d->start(&d->data, d);
+		if (d->start) {
+			int ret;
+
+			d->in_start = true;
+			ret = d->start(&d->data, d);
+			d->in_start = false;
+			return ret;
+		}
 	}
 	return 0;
 }
 
 static int dlfilter__stop(struct dlfilter *d)
 {
-	if (d && d->stop)
-		return d->stop(d->data, d);
+	if (d && d->stop) {
+		int ret;
+
+		d->in_stop = true;
+		ret = d->stop(d->data, d);
+		d->in_stop = false;
+		return ret;
+	}
 	return 0;
 }
 
diff --git a/tools/perf/util/dlfilter.h b/tools/perf/util/dlfilter.h
index a1ed38da3ce6..505980442360 100644
--- a/tools/perf/util/dlfilter.h
+++ b/tools/perf/util/dlfilter.h
@@ -23,6 +23,10 @@ struct dlfilter {
 	void				*data;
 	struct perf_session		*session;
 	bool				ctx_valid;
+	bool				in_start;
+	bool				in_stop;
+	int				dlargc;
+	char				**dlargv;
 
 	union perf_event		*event;
 	struct perf_sample		*sample;
@@ -47,7 +51,7 @@ struct dlfilter {
 	struct perf_dlfilter_fns *fns;
 };
 
-struct dlfilter *dlfilter__new(const char *file);
+struct dlfilter *dlfilter__new(const char *file, int dlargc, char **dlargv);
 
 int dlfilter__start(struct dlfilter *d, struct perf_session *session);
 
diff --git a/tools/perf/util/perf_dlfilter.h b/tools/perf/util/perf_dlfilter.h
index 31ad4c100181..35e03aa41a7f 100644
--- a/tools/perf/util/perf_dlfilter.h
+++ b/tools/perf/util/perf_dlfilter.h
@@ -90,8 +90,10 @@ struct perf_dlfilter_fns {
 	const struct perf_dlfilter_al *(*resolve_ip)(void *ctx);
 	/* Return information about addr (if addr_correlates_sym) */
 	const struct perf_dlfilter_al *(*resolve_addr)(void *ctx);
+	/* Return arguments from --dlarg option */
+	char **(*args)(void *ctx, int *dlargc);
 	/* Reserved */
-	void *(*reserved[126])(void *);
+	void *(*reserved[125])(void *);
 };
 
 /*