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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 438B4C197A0 for ; Mon, 20 Nov 2023 22:19:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232528AbjKTWTl (ORCPT ); Mon, 20 Nov 2023 17:19:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37496 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229798AbjKTWTj (ORCPT ); Mon, 20 Nov 2023 17:19:39 -0500 Received: from mail-pl1-x632.google.com (mail-pl1-x632.google.com [IPv6:2607:f8b0:4864:20::632]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F3511ED for ; Mon, 20 Nov 2023 14:19:35 -0800 (PST) Received: by mail-pl1-x632.google.com with SMTP id d9443c01a7336-1cf6af8588fso4598305ad.0 for ; Mon, 20 Nov 2023 14:19:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1700518775; x=1701123575; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:sender:from:to:cc:subject:date :message-id:reply-to; bh=2XOoFK7iiRtg8F9n1yVwN4BqrDcgETLBQgehwgQkqSk=; b=YktyFqrINYIrDa2sVdT9aw/3Nv6up+b0BlReQBNqLCzQaC2aB5bh4d4owSVBMc7bKu DhG9U0c3IkBP1fhHK6UMRZc/8uM1hr4i7fBe3rDJuHLmZi4c3DdWaP+ZkK/J8I6eOUTv dOj/6LINxR0oKsgggtdt6oGO9p2yPesBl3OkJlAI9inEdxAlkqd/+DXBhwfenZHYgEe8 sKX5I9faUGnQJcictpeHNWc7CiWFqlYsfRgzmESHLj7lQ+94pSCXz8LQQu89NVqfot80 qUSpvU4QxxGA9BCK/GNSuDaB1xBYNwEUAReZS7NaU5ljsAgQqoN33RrMe8NcJ3I3KrX8 bV0g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700518775; x=1701123575; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:sender:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=2XOoFK7iiRtg8F9n1yVwN4BqrDcgETLBQgehwgQkqSk=; b=SuW/Yypu2azxNLcDX8BOgoPKeXVar/xkO2cC/KnXnVNaWBglvNYRcMgYq/N3EqZJRf 2e1IALH7G3pXKRHg+9DW1+taE7D3pwdvnzsY0RWsGUMFUbl8KEKjKKKJzObN6nx6ZG7I 9AcbhFF6nwME2OMTyVOB15CLik/b14Up3HNjlcDMVz80ji9aCaT5zWBT2H26Ratv9U3+ oOZhm9sZVOWkEkYPNTk6dN6KxzwUTEj3Dt17VPtzzy7rdn+cRbC3oymd8W86LgYhilit DzvNIwf3n+q4dSykr9EsJ/uCTTuhtRuhWxvqyrKAVa6ee41I41/FPHRTR0++G8S21PHT JsuQ== X-Gm-Message-State: AOJu0Yw9MnpuEvZ8QYbxqj3Vj+E9Ye8P06zP7F0WzKoLMzO9s3szisKo VPQlNHrSUOazvmQLSfl3CRI= X-Google-Smtp-Source: AGHT+IFe8/tu8lmkUhi/3HijxlK6JcBhy81W2ka8TQGFI8ER6H2h5FUD3/MVnOwhRNRiUQBx3VkmYQ== X-Received: by 2002:a17:902:7682:b0:1b8:954c:1f6 with SMTP id m2-20020a170902768200b001b8954c01f6mr10400426pll.36.1700518775351; Mon, 20 Nov 2023 14:19:35 -0800 (PST) Received: from bangji.hsd1.ca.comcast.net ([2601:647:6780:42e0:75c6:4212:ae99:93b6]) by smtp.gmail.com with ESMTPSA id d4-20020a170902c18400b001c9c47d6cb9sm3528246pld.99.2023.11.20.14.19.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Nov 2023 14:19:35 -0800 (PST) Sender: Namhyung Kim From: Namhyung Kim To: Peter Zijlstra , Ingo Molnar Cc: Mark Rutland , Alexander Shishkin , Arnaldo Carvalho de Melo , LKML , Ian Rogers , Kan Liang , Mingwei Zhang Subject: [PATCH 2/3] perf/core: Reduce PMU access to adjust sample freq Date: Mon, 20 Nov 2023 14:19:31 -0800 Message-ID: <20231120221932.213710-2-namhyung@kernel.org> X-Mailer: git-send-email 2.43.0.rc1.413.gea7ed67945-goog In-Reply-To: <20231120221932.213710-1-namhyung@kernel.org> References: <20231120221932.213710-1-namhyung@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org For throttled events, it first starts the event and then stop unnecessarily. As it's already stopped, it can directly adjust the frequency and then move on. Signed-off-by: Namhyung Kim --- kernel/events/core.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 53e2ad73102d..fd3449e4d081 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4119,10 +4119,15 @@ static void perf_adjust_freq_unthr_events(struct list_head *event_list) if (hwc->interrupts == MAX_INTERRUPTS) { hwc->interrupts = 0; perf_log_throttle(event, 1); - event->pmu->start(event, 0); - } - if (!event->attr.freq || !event->attr.sample_freq) + if (!event->attr.freq || !event->attr.sample_freq) { + delta = 0; + goto next; + } + + if (event->hw.state & PERF_HES_STOPPED) + goto adjust; + } else if (!event->attr.freq || !event->attr.sample_freq) continue; /* @@ -4130,6 +4135,7 @@ static void perf_adjust_freq_unthr_events(struct list_head *event_list) */ event->pmu->stop(event, PERF_EF_UPDATE); +adjust: now = local64_read(&event->count); delta = now - hwc->freq_count_stamp; hwc->freq_count_stamp = now; @@ -4144,6 +4150,7 @@ static void perf_adjust_freq_unthr_events(struct list_head *event_list) if (delta > 0) perf_adjust_period(event, period, delta, false); +next: event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); } } -- 2.43.0.rc1.413.gea7ed67945-goog