[PATCH] perf util: optimize util/machine.c:machines__find().

[Dongsheng Yang <yangds.fnst@cn.fujitsu.com>]

* Remove an unnecessary variable default_machine.
* Return earlier to avoid unnecessary searching in children.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
---
 tools/perf/util/machine.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 84cdb07..f0dd5f6 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -175,8 +175,7 @@ struct machine *machines__find(struct machines *machines, pid_t pid)
 {
 	struct rb_node **p = &machines->guests.rb_node;
 	struct rb_node *parent = NULL;
-	struct machine *machine;
-	struct machine *default_machine = NULL;
+	struct machine *machine = NULL;
 
 	if (pid == HOST_KERNEL_ID)
 		return &machines->host;
@@ -184,17 +183,17 @@ struct machine *machines__find(struct machines *machines, pid_t pid)
 	while (*p != NULL) {
 		parent = *p;
 		machine = rb_entry(parent, struct machine, rb_node);
+		if (!machine->pid)
+			break;
 		if (pid < machine->pid)
 			p = &(*p)->rb_left;
 		else if (pid > machine->pid)
 			p = &(*p)->rb_right;
 		else
-			return machine;
-		if (!machine->pid)
-			default_machine = machine;
+			break;
 	}
 
-	return default_machine;
+	return machine;
 }
 
 struct machine *machines__findnew(struct machines *machines, pid_t pid)
-- 
1.8.2.1