From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759060AbbA3Cf5 (ORCPT ); Thu, 29 Jan 2015 21:35:57 -0500 Received: from LGEMRELSE7Q.lge.com ([156.147.1.151]:51179 "EHLO lgemrelse7q.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752285AbbA3Cf4 (ORCPT ); Thu, 29 Jan 2015 21:35:56 -0500 X-Original-SENDERIP: 10.177.220.203 X-Original-MAILFROM: namhyung@kernel.org From: Namhyung Kim To: Arnaldo Carvalho de Melo Cc: Ingo Molnar , Peter Zijlstra , Jiri Olsa , LKML Subject: [PATCH 2/3] perf tools: Do not rely on dso__data_read_offset() to open dso Date: Fri, 30 Jan 2015 11:33:28 +0900 Message-Id: <1422585209-32742-2-git-send-email-namhyung@kernel.org> X-Mailer: git-send-email 2.2.2 In-Reply-To: <1422585209-32742-1-git-send-email-namhyung@kernel.org> References: <1422585209-32742-1-git-send-email-namhyung@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Do not rely on dso__data_read_offset() will always call dso__data_fd() internally. With multi-thread support, accessing a fd will be protected by a lock and it'll cause a huge contention. It can be avoided since we can skip reading from file if there's a data in the dso cache. If one needs to call the dso__data_read_offset(), [s]he also needs to call dso__data_fd() (or set dso->binary_type at least) first like the dwarf unwind code does. Signed-off-by: Namhyung Kim --- tools/perf/tests/dso-data.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/tools/perf/tests/dso-data.c b/tools/perf/tests/dso-data.c index 22a8c428283a..513e5febbe5a 100644 --- a/tools/perf/tests/dso-data.c +++ b/tools/perf/tests/dso-data.c @@ -112,6 +112,9 @@ int test__dso_data(void) dso = dso__new((const char *)file); + TEST_ASSERT_VAL("Failed to access to dso", + dso__data_fd(dso, &machine) >= 0); + /* Basic 10 bytes tests. */ for (i = 0; i < ARRAY_SIZE(offsets); i++) { struct test_data_offset *data = &offsets[i]; @@ -252,13 +255,13 @@ int test__dso_data_cache(void) struct dso *dso = dsos[i]; /* - * Open dsos via dso__data_fd or dso__data_read_offset. - * Both opens the data file and keep it open. + * Open dsos via dso__data_fd(), it opens the data + * file and keep it open (unless open file limit). */ + fd = dso__data_fd(dso, &machine); + TEST_ASSERT_VAL("failed to get fd", fd > 0); + if (i % 2) { - fd = dso__data_fd(dso, &machine); - TEST_ASSERT_VAL("failed to get fd", fd > 0); - } else { #define BUFSIZE 10 u8 buf[BUFSIZE]; ssize_t n; -- 2.2.2