[PATCH 4/4] tracing: uprobe: eprobes: Allocate traceprobe_parse_context per probe

["Masami Hiramatsu (Google)" <mhiramat@kernel.org>]

From: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Since traceprobe_parse_context is reusable among a probe arguments,
it is more efficient to allocate it outside of the loop for parsing
probe argument as kprobe and fprobe events do.

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
 kernel/trace/trace_eprobe.c |   32 ++++++++++++--------------------
 kernel/trace/trace_uprobe.c |   12 ++++++------
 2 files changed, 18 insertions(+), 26 deletions(-)

diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
index f7a1ff509d7e..d58d8702a327 100644
--- a/kernel/trace/trace_eprobe.c
+++ b/kernel/trace/trace_eprobe.c
@@ -801,25 +801,6 @@ find_and_get_event(const char *system, const char *event_name)
 	return NULL;
 }
 
-static int trace_eprobe_tp_update_arg(struct trace_eprobe *ep, const char *argv[], int i)
-{
-	struct traceprobe_parse_context *ctx __free(traceprobe_parse_context) = NULL;
-	int ret;
-
-	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
-	if (!ctx)
-		return -ENOMEM;
-	ctx->event = ep->event;
-	ctx->flags = TPARG_FL_KERNEL | TPARG_FL_TEVENT;
-
-	ret = traceprobe_parse_probe_arg(&ep->tp, i, argv[i], ctx);
-	/* Handle symbols "@" */
-	if (!ret)
-		ret = traceprobe_update_arg(&ep->tp.args[i]);
-
-	return ret;
-}
-
 static int trace_eprobe_parse_filter(struct trace_eprobe *ep, int argc, const char *argv[])
 {
 	struct event_filter *dummy = NULL;
@@ -871,6 +852,7 @@ static int __trace_eprobe_create(int argc, const char *argv[])
 	 * Fetch args (no space):
 	 *  <name>=$<field>[:TYPE]
 	 */
+	struct traceprobe_parse_context *ctx __free(traceprobe_parse_context) = NULL;
 	struct trace_eprobe *ep __free(trace_event_probe_cleanup) = NULL;
 	const char *trlog __free(trace_probe_log_clear) = NULL;
 	const char *event = NULL, *group = EPROBE_EVENT_SYSTEM;
@@ -956,11 +938,21 @@ static int __trace_eprobe_create(int argc, const char *argv[])
 	} else
 		ep->filter_str = NULL;
 
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+	ctx->event = ep->event;
+	ctx->flags = TPARG_FL_KERNEL | TPARG_FL_TEVENT;
+
 	argc -= 2; argv += 2;
 	/* parse arguments */
 	for (i = 0; i < argc; i++) {
 		trace_probe_log_set_index(i + 2);
-		ret = trace_eprobe_tp_update_arg(ep, argv, i);
+
+		ret = traceprobe_parse_probe_arg(&ep->tp, i, argv[i], ctx);
+		/* Handle symbols "@" */
+		if (!ret)
+			ret = traceprobe_update_arg(&ep->tp.args[i]);
 		if (ret)
 			return ret;
 	}
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 9c628dab3dc6..8f9b95cee786 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -541,6 +541,7 @@ DEFINE_FREE(free_trace_uprobe, struct trace_uprobe *, if (_T) free_trace_uprobe(
  */
 static int __trace_uprobe_create(int argc, const char **argv)
 {
+	struct traceprobe_parse_context *ctx __free(traceprobe_parse_context) = NULL;
 	struct trace_uprobe *tu __free(free_trace_uprobe) = NULL;
 	const char *trlog __free(trace_probe_log_clear) = NULL;
 	const char *event = NULL, *group = UPROBE_EVENT_SYSTEM;
@@ -698,14 +699,13 @@ static int __trace_uprobe_create(int argc, const char **argv)
 	memset(&path, 0, sizeof(path));
 	tu->filename = no_free_ptr(filename);
 
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+	ctx->flags = (is_return ? TPARG_FL_RETURN : 0) | TPARG_FL_USER;
+
 	/* parse arguments */
 	for (i = 0; i < argc; i++) {
-		struct traceprobe_parse_context *ctx __free(traceprobe_parse_context)
-			= kzalloc(sizeof(*ctx), GFP_KERNEL);
-
-		if (!ctx)
-			return -ENOMEM;
-		ctx->flags = (is_return ? TPARG_FL_RETURN : 0) | TPARG_FL_USER;
 		trace_probe_log_set_index(i + 2);
 		ret = traceprobe_parse_probe_arg(&tu->tp, i, argv[i], ctx);
 		if (ret)