From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932977AbeBPJxE (ORCPT ); Fri, 16 Feb 2018 04:53:04 -0500 Received: from terminus.zytor.com ([198.137.202.136]:35803 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932690AbeBPJxC (ORCPT ); Fri, 16 Feb 2018 04:53:02 -0500 Date: Fri, 16 Feb 2018 01:37:18 -0800 From: tip-bot for Kan Liang Message-ID: Cc: jolsa@kernel.org, hpa@zytor.com, mingo@kernel.org, peterz@infradead.org, tglx@linutronix.de, linux-kernel@vger.kernel.org, namhyung@kernel.org, ak@linux.intel.com, acme@redhat.com, wangnan0@huawei.com, kan.liang@intel.com, yao.jin@linux.intel.com Reply-To: jolsa@kernel.org, hpa@zytor.com, peterz@infradead.org, mingo@kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, namhyung@kernel.org, ak@linux.intel.com, acme@redhat.com, wangnan0@huawei.com, kan.liang@intel.com, yao.jin@linux.intel.com In-Reply-To: <1516310792-208685-8-git-send-email-kan.liang@intel.com> References: <1516310792-208685-8-git-send-email-kan.liang@intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/urgent] perf mmap: Introduce perf_mmap__read_done() Git-Commit-ID: ee023de05f35484691f7d9e5c1f92195ac4d64d2 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: ee023de05f35484691f7d9e5c1f92195ac4d64d2 Gitweb: https://git.kernel.org/tip/ee023de05f35484691f7d9e5c1f92195ac4d64d2 Author: Kan Liang AuthorDate: Thu, 18 Jan 2018 13:26:22 -0800 Committer: Arnaldo Carvalho de Melo CommitDate: Thu, 15 Feb 2018 09:53:15 -0300 perf mmap: Introduce perf_mmap__read_done() The direction of overwrite mode is backward. The last perf_mmap__read() will set tail to map->prev. Need to correct the map->prev to head which is the end of next read. It will be used later. Signed-off-by: Kan Liang Acked-by: Jiri Olsa Cc: Andi Kleen Cc: Jin Yao Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/r/1516310792-208685-8-git-send-email-kan.liang@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/mmap.c | 11 +++++++++++ tools/perf/util/mmap.h | 1 + 2 files changed, 12 insertions(+) diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c index 125bfda..4f59eae 100644 --- a/tools/perf/util/mmap.c +++ b/tools/perf/util/mmap.c @@ -338,3 +338,14 @@ int perf_mmap__push(struct perf_mmap *md, bool overwrite, out: return rc; } + +/* + * Mandatory for overwrite mode + * The direction of overwrite mode is backward. + * The last perf_mmap__read() will set tail to map->prev. + * Need to correct the map->prev to head which is the end of next read. + */ +void perf_mmap__read_done(struct perf_mmap *map) +{ + map->prev = perf_mmap__read_head(map); +} diff --git a/tools/perf/util/mmap.h b/tools/perf/util/mmap.h index 9ab2b48..95549d4 100644 --- a/tools/perf/util/mmap.h +++ b/tools/perf/util/mmap.h @@ -96,4 +96,5 @@ size_t perf_mmap__mmap_len(struct perf_mmap *map); int perf_mmap__read_init(struct perf_mmap *md, bool overwrite, u64 *startp, u64 *endp); +void perf_mmap__read_done(struct perf_mmap *map); #endif /*__PERF_MMAP_H */