From 2c478c7eb8b18468d021f31682f0182ba67cca3c Mon Sep 17 00:00:00 2001
From: Tom Zanussi <tom.zanussi@linux.intel.com>
Date: Mon, 15 Jan 2018 20:52:02 -0600
Subject: [PATCH 104/518] tracing: Allow whitespace to surround hist trigger
 filter

The existing code only allows for one space before and after the 'if'
specifying the filter for a hist trigger.  Add code to make that more
permissive as far as whitespace goes.  Specifically, we want to allow
spaces in the trigger itself now that we have additional syntax
(onmatch/onmax) where spaces are more natural e.g. spaces after commas
in param lists.

Link: http://lkml.kernel.org/r/1053090c3c308d4f431accdeb59dff4b511d4554.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
(cherry picked from commit ab257ec0f8eb50c58fafd50b1cb5352553f31ccf)
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 kernel/trace/trace_events_hist.c | 37 +++++++++++++++++++++++++++-----
 1 file changed, 32 insertions(+), 5 deletions(-)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 6a9c7a1c92011..98f808e8fd83b 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -5165,7 +5165,7 @@ static int event_hist_trigger_func(struct event_command *cmd_ops,
 	struct synth_event *se;
 	const char *se_name;
 	bool remove = false;
-	char *trigger;
+	char *trigger, *p;
 	int ret = 0;
 
 	if (!param)
@@ -5174,10 +5174,37 @@ static int event_hist_trigger_func(struct event_command *cmd_ops,
 	if (glob[0] == '!')
 		remove = true;
 
-	/* separate the trigger from the filter (k:v [if filter]) */
-	trigger = strsep(&param, " \t");
-	if (!trigger)
-		return -EINVAL;
+	/*
+	 * separate the trigger from the filter (k:v [if filter])
+	 * allowing for whitespace in the trigger
+	 */
+	p = trigger = param;
+	do {
+		p = strstr(p, "if");
+		if (!p)
+			break;
+		if (p == param)
+			return -EINVAL;
+		if (*(p - 1) != ' ' && *(p - 1) != '\t') {
+			p++;
+			continue;
+		}
+		if (p >= param + strlen(param) - strlen("if") - 1)
+			return -EINVAL;
+		if (*(p + strlen("if")) != ' ' && *(p + strlen("if")) != '\t') {
+			p++;
+			continue;
+		}
+		break;
+	} while (p);
+
+	if (!p)
+		param = NULL;
+	else {
+		*(p - 1) = '\0';
+		param = strstrip(p);
+		trigger = strstrip(trigger);
+	}
 
 	attrs = parse_hist_trigger_attrs(trigger);
 	if (IS_ERR(attrs))
-- 
2.41.0

