From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753618AbdJCM4R (ORCPT ); Tue, 3 Oct 2017 08:56:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:55114 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753145AbdJCM4O (ORCPT ); Tue, 3 Oct 2017 08:56:14 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 62D93218B7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=acme@kernel.org From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Kan Liang , Adrian Hunter , Alexei Starovoitov , Andi Kleen , He Kuang , Lukasz Odzioba , Namhyung Kim , Peter Zijlstra , Wang Nan , Arnaldo Carvalho de Melo Subject: [PATCH 5/8] perf tools: Lock to protect comm_str rb tree Date: Tue, 3 Oct 2017 09:55:37 -0300 Message-Id: <20171003125540.331-6-acme@kernel.org> X-Mailer: git-send-email 2.13.6 In-Reply-To: <20171003125540.331-1-acme@kernel.org> References: <20171003125540.331-1-acme@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kan Liang Add comm_str_lock to protect comm_str rb tree. The lock is only needed for multithreaded code, so using mutex wrappers provided by perf tool. Signed-off-by: Kan Liang Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Alexei Starovoitov Cc: Andi Kleen Cc: He Kuang Cc: Lukasz Odzioba Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/r/1506696477-146932-3-git-send-email-kan.liang@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/comm.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/comm.c b/tools/perf/util/comm.c index 7bc981b6bf29..756a9c14efbb 100644 --- a/tools/perf/util/comm.c +++ b/tools/perf/util/comm.c @@ -5,6 +5,7 @@ #include #include #include +#include "rwsem.h" struct comm_str { char *str; @@ -14,6 +15,7 @@ struct comm_str { /* Should perhaps be moved to struct machine */ static struct rb_root comm_str_root; +static struct rw_semaphore comm_str_lock = {.lock = PTHREAD_RWLOCK_INITIALIZER,}; static struct comm_str *comm_str__get(struct comm_str *cs) { @@ -25,7 +27,9 @@ static struct comm_str *comm_str__get(struct comm_str *cs) static void comm_str__put(struct comm_str *cs) { if (cs && refcount_dec_and_test(&cs->refcnt)) { + down_write(&comm_str_lock); rb_erase(&cs->rb_node, &comm_str_root); + up_write(&comm_str_lock); zfree(&cs->str); free(cs); } @@ -50,7 +54,8 @@ static struct comm_str *comm_str__alloc(const char *str) return cs; } -static struct comm_str *comm_str__findnew(const char *str, struct rb_root *root) +static +struct comm_str *__comm_str__findnew(const char *str, struct rb_root *root) { struct rb_node **p = &root->rb_node; struct rb_node *parent = NULL; @@ -81,6 +86,17 @@ static struct comm_str *comm_str__findnew(const char *str, struct rb_root *root) return new; } +static struct comm_str *comm_str__findnew(const char *str, struct rb_root *root) +{ + struct comm_str *cs; + + down_write(&comm_str_lock); + cs = __comm_str__findnew(str, root); + up_write(&comm_str_lock); + + return cs; +} + struct comm *comm__new(const char *str, u64 timestamp, bool exec) { struct comm *comm = zalloc(sizeof(*comm)); -- 2.13.6