From patchwork Fri May 6 00:29:39 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnaldo Carvalho de Melo X-Patchwork-Id: 67245 Delivered-To: patch@linaro.org Received: by 10.140.92.199 with SMTP id b65csp58534qge; Thu, 5 May 2016 17:30:58 -0700 (PDT) X-Received: by 10.98.35.12 with SMTP id j12mr24892961pfj.73.1462494658132; Thu, 05 May 2016 17:30:58 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id tn9si14412948pac.31.2016.05.05.17.30.57; Thu, 05 May 2016 17:30:58 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932097AbcEFAa4 (ORCPT + 29 others); Thu, 5 May 2016 20:30:56 -0400 Received: from merlin.infradead.org ([205.233.59.134]:55112 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757662AbcEFAaI (ORCPT ); Thu, 5 May 2016 20:30:08 -0400 Received: from [187.65.41.114] (helo=jouet.infradead.org) by merlin.infradead.org with esmtpsa (Exim 4.85_2 #1 (Red Hat Linux)) id 1ayTeR-0004lb-F2; Fri, 06 May 2016 00:29:51 +0000 Received: by jouet.infradead.org (Postfix, from userid 1000) id 3B96F143814; Thu, 5 May 2016 21:29:47 -0300 (BRT) From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Wang Nan , Peter Zijlstra , Zefan Li , pi3orama@163.com, Arnaldo Carvalho de Melo Subject: [PATCH 16/17] perf evlist: Extract perf_mmap__read() Date: Thu, 5 May 2016 21:29:39 -0300 Message-Id: <1462494580-27164-17-git-send-email-acme@kernel.org> X-Mailer: git-send-email 2.5.5 In-Reply-To: <1462494580-27164-1-git-send-email-acme@kernel.org> References: <1462494580-27164-1-git-send-email-acme@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by merlin.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wang Nan Extract event reader from perf_evlist__mmap_read() to perf__mmap_read(). Future commit will feed it with manually computed 'head' and 'old' pointers. Signed-off-by: Wang Nan Cc: Peter Zijlstra Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1461723563-67451-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/evlist.c | 39 ++++++++++++++++++++++++--------------- 1 file changed, 24 insertions(+), 15 deletions(-) -- 2.5.5 diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 85271e54a63b..96c71916e367 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -679,24 +679,15 @@ static struct perf_evsel *perf_evlist__event2evsel(struct perf_evlist *evlist, return NULL; } -union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx) +static union perf_event * +perf_mmap__read(struct perf_mmap *md, bool overwrite, u64 head, + u64 old, u64 *prev) { - struct perf_mmap *md = &evlist->mmap[idx]; - u64 head; - u64 old = md->prev; - int diff; unsigned char *data = md->base + page_size; union perf_event *event = NULL; + int diff = head - old; - /* - * Check if event was unmapped due to a POLLHUP/POLLERR. - */ - if (!atomic_read(&md->refcnt)) - return NULL; - - head = perf_mmap__read_head(md); - diff = head - old; - if (evlist->overwrite) { + if (overwrite) { /* * If we're further behind than half the buffer, there's a chance * the writer will bite our tail and mess up the samples under us. @@ -751,11 +742,29 @@ union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx) } broken_event: - md->prev = old; + if (prev) + *prev = old; return event; } +union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx) +{ + struct perf_mmap *md = &evlist->mmap[idx]; + u64 head; + u64 old = md->prev; + + /* + * Check if event was unmapped due to a POLLHUP/POLLERR. + */ + if (!atomic_read(&md->refcnt)) + return NULL; + + head = perf_mmap__read_head(md); + + return perf_mmap__read(md, evlist->overwrite, head, old, &md->prev); +} + static bool perf_mmap__empty(struct perf_mmap *md) { return perf_mmap__read_head(md) == md->prev && !md->auxtrace_mmap.base;