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 16D18C00140 for ; Mon, 22 Aug 2022 02:16:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232449AbiHVCQf (ORCPT ); Sun, 21 Aug 2022 22:16:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52168 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232372AbiHVCQQ (ORCPT ); Sun, 21 Aug 2022 22:16:16 -0400 Received: from mail-pf1-x42a.google.com (mail-pf1-x42a.google.com [IPv6:2607:f8b0:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A6E8522B00 for ; Sun, 21 Aug 2022 19:16:09 -0700 (PDT) Received: by mail-pf1-x42a.google.com with SMTP id y15so5045101pfr.9 for ; Sun, 21 Aug 2022 19:16:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc; bh=gsR63uXiD4J4dRjeMZsAaLt2fDvFcRZsnDNlGseIAjE=; b=Pk0rIhqwd8AcUkq5KmJe9mjrUF6uNVfJWfjWUkbfwuQIGmV+U3/UFgPVoh1gYGq+bd lbCSRPMb+1x0M86+ymqwzFqN8nb+l68wSITrsmEixSWhlHgDZLB/R0svIyy5MO54R6Ym PwVfSVkrB8SoRCQ7vzL1LQZzM9iHBwApzh6vrmeiZsltT6ynaL3sdrb1ZhJGPhmFyOD3 4s2db1YqPkPeaWJ6qcSkXxuYfgRl3Eokk297cD1GGHz/Q5l5MVSGxbVpp3c4meit/hP+ bSsrrIKUfzH3yc9hotWq9Z7duppQSn0jH3GGkXZbsN3yxozQbvoh5tqw/X+vXNhleLsl cX7A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc; bh=gsR63uXiD4J4dRjeMZsAaLt2fDvFcRZsnDNlGseIAjE=; b=HOHcPCk4ASOtghHeID7Onllfy2UXYmYiS7ExjKij6GSBU+H4cK3DYzht9dKrOUrREy +gmiF8xqJQIia3KZLyCfElryBVBVPGbX+par2yJJZE5iGZefgcPryLUKgStxQQWYky3Q TAOzkD57sbXwHk1fl5Oeg+XQ87RMIEfrzojp7gA84yS3CJqcFW2BGFcoemn9nJBwqX+H FXu9ZHIgBhQ1+8T9CC0e+WoispqEyPTfIIo+6GOZNhMA9mAP6ntmDw2Qh4b0x1ZTCD36 p1fLPBHVN3g9x0huuYa0wp5l97BR+oJ/zkLMvhs/bbz9VcmJPwgXHq6TC0uY0sP14kTp Q54w== X-Gm-Message-State: ACgBeo2idlwXL+UOwDH/hQ6U1tyHhEhqbjhNRe84mU6LpMF2AN+vZxoN Vv7satEu20mADWevzrtpTl8G39mY1Q== X-Google-Smtp-Source: AA6agR796+xdB/mm2oEQUhLS61HVQaOmFzmcD/yNrFj1veXL2aZ9RxDMlPamwMMKooh9so1wCzMtIA== X-Received: by 2002:a63:4b62:0:b0:421:8c8b:163c with SMTP id k34-20020a634b62000000b004218c8b163cmr14624442pgl.182.1661134569229; Sun, 21 Aug 2022 19:16:09 -0700 (PDT) Received: from piliu.users.ipa.redhat.com ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id k3-20020aa79723000000b005321340753fsm7312139pfg.103.2022.08.21.19.16.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 21 Aug 2022 19:16:08 -0700 (PDT) From: Pingfan Liu To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Pingfan Liu , Will Deacon , Mark Rutland Subject: [RFC 05/10] perf/arm-dsu: Make dsu_pmu_cpu_teardown() parallel Date: Mon, 22 Aug 2022 10:15:15 +0800 Message-Id: <20220822021520.6996-6-kernelfans@gmail.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20220822021520.6996-1-kernelfans@gmail.com> References: <20220822021520.6996-1-kernelfans@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In the case of kexec quick reboot, dsu_pmu_cpu_teardown() confronts parallel and lock are needed to protect the contest on a dsu_pmu. Signed-off-by: Pingfan Liu Cc: Will Deacon Cc: Mark Rutland To: linux-arm-kernel@lists.infradead.org To: linux-kernel@vger.kernel.org --- drivers/perf/arm_dsu_pmu.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/perf/arm_dsu_pmu.c b/drivers/perf/arm_dsu_pmu.c index a36698a90d2f..aa9f4393ff0c 100644 --- a/drivers/perf/arm_dsu_pmu.c +++ b/drivers/perf/arm_dsu_pmu.c @@ -833,16 +833,23 @@ static int dsu_pmu_cpu_teardown(unsigned int cpu, struct hlist_node *node) struct dsu_pmu *dsu_pmu = hlist_entry_safe(node, struct dsu_pmu, cpuhp_node); - if (!cpumask_test_and_clear_cpu(cpu, &dsu_pmu->active_cpu)) + raw_spin_lock(&dsu_pmu->pmu_lock); + if (!cpumask_test_and_clear_cpu(cpu, &dsu_pmu->active_cpu)) { + raw_spin_unlock(&dsu_pmu->pmu_lock); return 0; + } dst = dsu_pmu_get_online_cpu_any_but(dsu_pmu, cpu); /* If there are no active CPUs in the DSU, leave IRQ disabled */ - if (dst >= nr_cpu_ids) + if (dst >= nr_cpu_ids) { + raw_spin_unlock(&dsu_pmu->pmu_lock); return 0; + } - perf_pmu_migrate_context(&dsu_pmu->pmu, cpu, dst); + /* dst should not be in dying mask. So after setting, blocking parallel */ dsu_pmu_set_active_cpu(dst, dsu_pmu); + raw_spin_unlock(&dsu_pmu->pmu_lock); + perf_pmu_migrate_context(&dsu_pmu->pmu, cpu, dst); return 0; } @@ -858,6 +865,7 @@ static int __init dsu_pmu_init(void) if (ret < 0) return ret; dsu_pmu_cpuhp_state = ret; + cpuhp_set_step_parallel(ret); return platform_driver_register(&dsu_pmu_driver); } -- 2.31.1