linux-kernel - [tip:perf/core] perf machine: Optimize a bit the machine__findnew

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Date:   Fri, 22 Sep 2017 09:42:54 -0700
From:   tip-bot for Arnaldo Carvalho de Melo <tipbot@...or.com>
To:     linux-tip-commits@...r.kernel.org
Cc:     linux-kernel@...r.kernel.org, ak@...ux.intel.com, mingo@...nel.org,
        dsahern@...il.com, wangnan0@...wei.com, hpa@...or.com,
        peterz@...radead.org, acme@...hat.com, lukasz.odzioba@...el.com,
        kan.liang@...el.com, adrian.hunter@...el.com, namhyung@...nel.org,
        jolsa@...nel.org, tglx@...utronix.de
Subject: [tip:perf/core] perf machine: Optimize a bit the
 machine__findnew_thread() methods

Commit-ID:  75e45e432052c7b1a5da866cff88192db8be1445
Gitweb:     http://git.kernel.org/tip/75e45e432052c7b1a5da866cff88192db8be1445
Author:     Arnaldo Carvalho de Melo <acme@...hat.com>
AuthorDate: Thu, 14 Sep 2017 16:16:34 -0300
Committer:  Arnaldo Carvalho de Melo <acme@...hat.com>
CommitDate: Mon, 18 Sep 2017 09:40:19 -0300

perf machine: Optimize a bit the machine__findnew_thread() methods

In some cases we already have calculated the hash bucket, so reuse it.

Cc: Adrian Hunter <adrian.hunter@...el.com>
Cc: Andi Kleen <ak@...ux.intel.com>
Cc: David Ahern <dsahern@...il.com>
Cc: Jiri Olsa <jolsa@...nel.org>
Cc: Kan Liang <kan.liang@...el.com>
Cc: Lukasz Odzioba <lukasz.odzioba@...el.com>
Cc: Namhyung Kim <namhyung@...nel.org>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: Wang Nan <wangnan0@...wei.com>
Link: http://lkml.kernel.org/n/tip-800zehjsyy03er4s4jf0e99v@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@...hat.com>
---
 tools/perf/util/machine.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index f4f9267..ddeea05 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -399,10 +399,10 @@ out_err:
  * lookup/new thread inserted.
  */
 static struct thread *____machine__findnew_thread(struct machine *machine,
+						  struct threads *threads,
 						  pid_t pid, pid_t tid,
 						  bool create)
 {
-	struct threads *threads = machine__threads(machine, tid);
 	struct rb_node **p = &threads->entries.rb_node;
 	struct rb_node *parent = NULL;
 	struct thread *th;
@@ -473,7 +473,7 @@ static struct thread *____machine__findnew_thread(struct machine *machine,
 
 struct thread *__machine__findnew_thread(struct machine *machine, pid_t pid, pid_t tid)
 {
-	return ____machine__findnew_thread(machine, pid, tid, true);
+	return ____machine__findnew_thread(machine, machine__threads(machine, tid), pid, tid, true);
 }
 
 struct thread *machine__findnew_thread(struct machine *machine, pid_t pid,
@@ -495,7 +495,7 @@ struct thread *machine__find_thread(struct machine *machine, pid_t pid,
 	struct thread *th;
 
 	pthread_rwlock_rdlock(&threads->lock);
-	th =  ____machine__findnew_thread(machine, pid, tid, false);
+	th =  ____machine__findnew_thread(machine, threads, pid, tid, false);
 	pthread_rwlock_unlock(&threads->lock);
 	return th;
 }