From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnaldo Carvalho de Melo Subject: [PATCH 04/22] perf map: Remove extra indirection from map__find() Date: Fri, 30 Nov 2018 15:26:34 -0300 Message-ID: <20181130182652.23620-5-acme@kernel.org> References: <20181130182652.23620-1-acme@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20181130182652.23620-1-acme@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: Ingo Molnar Cc: Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Eric Saint-Etienne , Alexander Shishkin , Eric Saint-Etienne , Namhyung Kim , Peter Zijlstra , Arnaldo Carvalho de Melo List-Id: linux-perf-users.vger.kernel.org From: Eric Saint-Etienne A double pointer is used in map__find() where a single pointer is enough because the function doesn't affect the rbtree and the rbtree is locked. Signed-off-by: Eric Saint-Etienne Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Eric Saint-Etienne Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1542969759-24346-1-git-send-email-eric.saint.etienne@oracle.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/map.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c index 781eed8e3265..a0d58b4d9c32 100644 --- a/tools/perf/util/map.c +++ b/tools/perf/util/map.c @@ -873,19 +873,18 @@ void maps__remove(struct maps *maps, struct map *map) struct map *maps__find(struct maps *maps, u64 ip) { - struct rb_node **p, *parent = NULL; + struct rb_node *p; struct map *m; down_read(&maps->lock); - p = &maps->entries.rb_node; - while (*p != NULL) { - parent = *p; - m = rb_entry(parent, struct map, rb_node); + p = maps->entries.rb_node; + while (p != NULL) { + m = rb_entry(p, struct map, rb_node); if (ip < m->start) - p = &(*p)->rb_left; + p = p->rb_left; else if (ip >= m->end) - p = &(*p)->rb_right; + p = p->rb_right; else goto out; } -- 2.19.1