From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754158AbbG0Fnq (ORCPT ); Mon, 27 Jul 2015 01:43:46 -0400 Received: from e36.co.us.ibm.com ([32.97.110.154]:58122 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753369AbbG0FmE (ORCPT ); Mon, 27 Jul 2015 01:42:04 -0400 X-Helo: d03dlp01.boulder.ibm.com X-MailFrom: sukadev@linux.vnet.ibm.com X-RcptTo: sparclinux@vger.kernel.org From: Sukadev Bhattiprolu To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Michael Ellerman Cc: , linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org Subject: [PATCH 08/10] perf: Add return value to __perf_event_read() Date: Sun, 26 Jul 2015 22:40:36 -0700 Message-Id: <1437975638-789-9-git-send-email-sukadev@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1437975638-789-1-git-send-email-sukadev@linux.vnet.ibm.com> References: <1437975638-789-1-git-send-email-sukadev@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15072705-0021-0000-0000-00000EB72009 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a return value to __perf_event_read(). The return value will be needed later in perf_read_group() implements ability to read several counters in a PERF_PMU_TXN_READ transaction. Signed-off-by: Sukadev Bhattiprolu --- kernel/events/core.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index f38fe0b..951d835 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -3174,12 +3174,18 @@ void perf_event_exec(void) rcu_read_unlock(); } +struct perf_read_data { + struct perf_event *event; + int ret; +}; + /* * Cross CPU call to read the hardware event */ static void __perf_event_read(void *info) { - struct perf_event *event = info; + struct perf_read_data *data = info; + struct perf_event *event = data->event; struct perf_event_context *ctx = event->ctx; struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); @@ -3201,6 +3207,8 @@ static void __perf_event_read(void *info) update_event_times(event); if (event->state == PERF_EVENT_STATE_ACTIVE) event->pmu->read(event); + + data->ret = 0; raw_spin_unlock(&ctx->lock); } @@ -3214,13 +3222,21 @@ static inline u64 perf_event_count(struct perf_event *event) static int perf_event_read(struct perf_event *event, bool group) { + int ret = 0; + /* * If event is enabled and currently active on a CPU, update the * value in the event structure: */ if (event->state == PERF_EVENT_STATE_ACTIVE) { + struct perf_read_data data = { + .event = event, + .ret = 0, + }; + smp_call_function_single(event->oncpu, - __perf_event_read, event, 1); + __perf_event_read, &data, 1); + ret = data.ret; } else if (event->state == PERF_EVENT_STATE_INACTIVE) { struct perf_event_context *ctx = event->ctx; unsigned long flags; @@ -3244,7 +3260,7 @@ static int perf_event_read(struct perf_event *event, bool group) raw_spin_unlock_irqrestore(&ctx->lock, flags); } - return 0; + return ret; } /* -- 1.7.9.5