From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6EF59C43381 for ; Thu, 21 Mar 2019 20:59:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 477C32190A for ; Thu, 21 Mar 2019 20:59:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727298AbfCUU7c (ORCPT ); Thu, 21 Mar 2019 16:59:32 -0400 Received: from mga18.intel.com ([134.134.136.126]:34980 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727246AbfCUU7a (ORCPT ); Thu, 21 Mar 2019 16:59:30 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 21 Mar 2019 13:59:29 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,254,1549958400"; d="scan'208";a="154548130" Received: from otc-icl-cdi187.jf.intel.com ([10.54.55.103]) by fmsmga004.fm.intel.com with ESMTP; 21 Mar 2019 13:59:28 -0700 From: kan.liang@linux.intel.com To: peterz@infradead.org, acme@kernel.org, mingo@redhat.com, linux-kernel@vger.kernel.org Cc: tglx@linutronix.de, jolsa@kernel.org, eranian@google.com, alexander.shishkin@linux.intel.com, ak@linux.intel.com, Kan Liang Subject: [PATCH V2 12/23] perf/core: Support a REMOVE transaction Date: Thu, 21 Mar 2019 13:56:52 -0700 Message-Id: <20190321205703.4256-13-kan.liang@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190321205703.4256-1-kan.liang@linux.intel.com> References: <20190321205703.4256-1-kan.liang@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andi Kleen The TopDown events can be collected per thread/process on Icelake. To use TopDown through RDPMC in applications, the metrics and slots MSR values have to be saved/restored during context switching. It is useful to have a remove transaction when the counter is unscheduled, so that the values can be saved correctly. Add a remove transaction to the perf core. Signed-off-by: Andi Kleen Signed-off-by: Kan Liang --- Changes since V1: - Add more explanation in change log arch/x86/events/core.c | 3 +-- include/linux/perf_event.h | 1 + kernel/events/core.c | 5 +++++ 3 files changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 9378c6b2128f..9c14b4b3e457 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -1912,8 +1912,7 @@ static inline void x86_pmu_read(struct perf_event *event) * Set the flag to make pmu::enable() not perform the * schedulability test, it will be performed at commit time * - * We only support PERF_PMU_TXN_ADD transactions. Save the - * transaction flags but otherwise ignore non-PERF_PMU_TXN_ADD + * Save the transaction flags and ignore non-PERF_PMU_TXN_ADD * transactions. */ static void x86_pmu_start_txn(struct pmu *pmu, unsigned int txn_flags) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index e47ef764f613..fb258c171b2c 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -233,6 +233,7 @@ struct perf_event; */ #define PERF_PMU_TXN_ADD 0x1 /* txn to add/schedule event on PMU */ #define PERF_PMU_TXN_READ 0x2 /* txn to read event group from PMU */ +#define PERF_PMU_TXN_REMOVE 0x4 /* txn to remove event on PMU */ /** * pmu::capabilities flags diff --git a/kernel/events/core.c b/kernel/events/core.c index 1032a16bd186..dea8cfe2a891 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -2032,6 +2032,7 @@ group_sched_out(struct perf_event *group_event, struct perf_cpu_context *cpuctx, struct perf_event_context *ctx) { + struct pmu *pmu = ctx->pmu; struct perf_event *event; if (group_event->state != PERF_EVENT_STATE_ACTIVE) @@ -2039,6 +2040,8 @@ group_sched_out(struct perf_event *group_event, perf_pmu_disable(ctx->pmu); + pmu->start_txn(pmu, PERF_PMU_TXN_REMOVE); + event_sched_out(group_event, cpuctx, ctx); /* @@ -2051,6 +2054,8 @@ group_sched_out(struct perf_event *group_event, if (group_event->attr.exclusive) cpuctx->exclusive = 0; + + pmu->commit_txn(pmu); } #define DETACH_GROUP 0x01UL -- 2.17.1