From: Tom Zanussi <tom.zanussi@linux.intel.com>
Date: Mon, 26 Jun 2017 17:49:18 -0500
Subject: tracing: Account for variables in named trigger compatibility
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git
Git-commit: 108102bca2745ffb55441b882b61da7e5cb46dc5
Patch-mainline: Queued in subsystem maintainer repository
References: SLE Realtime Extension

Named triggers must also have the same set of variables in order to be
considered compatible - update the trigger match test to account for
that.

The reason for this requirement is that named triggers with variables
are meant to allow one or more events to set the same variable.

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Mike Galbraith <mgalbraith@suse.de>
---
 kernel/trace/trace_events_hist.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1545,7 +1545,7 @@ static int event_hist_trigger_print(stru
 		sort_key = &hist_data->sort_keys[i];
 		idx = sort_key->field_idx;
 
-		if (WARN_ON(idx >= TRACING_MAP_FIELDS_MAX))
+		if (WARN_ON(idx >= HIST_FIELDS_MAX))
 			return -EINVAL;
 
 		if (i > 0)
@@ -1733,6 +1733,12 @@ static bool hist_trigger_match(struct ev
 			return false;
 		if (key_field->is_signed != key_field_test->is_signed)
 			return false;
+		if ((key_field->var.name && !key_field_test->var.name) ||
+		    (!key_field->var.name && key_field_test->var.name))
+			return false;
+		if ((key_field->var.name && key_field_test->var.name) &&
+		     strcmp(key_field->var.name, key_field_test->var.name) != 0)
+			return false;
 	}
 
 	for (i = 0; i < hist_data->n_sort_keys; i++) {