From patchwork Tue Aug 22 18:01:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rob Clark X-Patchwork-Id: 716200 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 A4F4AC3DA66 for ; Tue, 22 Aug 2023 18:02:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229678AbjHVSCm (ORCPT ); Tue, 22 Aug 2023 14:02:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36374 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229645AbjHVSCl (ORCPT ); Tue, 22 Aug 2023 14:02:41 -0400 Received: from mail-pj1-x102a.google.com (mail-pj1-x102a.google.com [IPv6:2607:f8b0:4864:20::102a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B86F5CD7; Tue, 22 Aug 2023 11:02:38 -0700 (PDT) Received: by mail-pj1-x102a.google.com with SMTP id 98e67ed59e1d1-269304c135aso3288749a91.3; Tue, 22 Aug 2023 11:02:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1692727358; x=1693332158; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=+XShSbqbLSjOdDhersXOLs7lzCQuSfnKt14AX57BEfg=; b=pUZ+14WTjGDCf1BQn529IVVAU3hq39BWMLQDcxyh3ZnNRBdW80UywIS+1pmIIApzlC qwS842G1JCCQnTm2GE6oMZBJelvEJUhgD2Vt6d+kHraK7Dnkl31KoMaN4WQv2KPpm59X 7MZU2Ldos4yc3gUepBLpO9lBcwusarlG6zxLEYeX6CEbONCv3dq6NYXvPJNGCVz2TlEF 8IDQFIcKMxuxoF8DTAbGfanLO9KXBeSmSHFjrWlyJLnWnxFR5OMc7gC1wmwHSesOW1y9 4VgfyDskCki8nCRAB6ulGOZbQL7awkJoyYTayPWZF9yyiFx8tdwu5nGGw1vPvf66bNRo FFIQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692727358; x=1693332158; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=+XShSbqbLSjOdDhersXOLs7lzCQuSfnKt14AX57BEfg=; b=coOmU9ytivoc1NcpdkDzsolaYIgqSOm0fvm8Txhro3Y0/zVFVyqF2jekMuFKcBoXsk wVWuPoq+LvfvrvZZwNHmxdBE0uiTrg2UGEyDlFkSxHRwUAFNntOMWJ2KY7ksOPKwVpF/ nRvIEqMWqw04wfeZW4bKf5LRf2TDKXge9s0acOsTjd33hKtXxxfQboilcsBHzRvGLBEE KIfiLtakaWo3RukEpDfcSd84ZSfedxLJ0uGP+fhX2Zqm6o+HLEgG0P2mTXt+COmGiJZ9 YhsdvKaePK9OZugetOE/TIVA6aHKBY8th3j7ncM/ECiPhcWBIJCAEcZbvpCtzOM5xevt 6CGQ== X-Gm-Message-State: AOJu0YzOO0qy3s4fF2AwscHei1mTF4bBUEUje3dgNtpC8Y0Cwt5gB+4I gTwbOSHVV+9JbyHIWRDV9dc= X-Google-Smtp-Source: AGHT+IGU2q4GqtMlWZay5JuzPmetg/Z4r0XDExQ7OUUvf4EpBFUGF1s2dS8kYHGsXJw0CZke5NhQ/g== X-Received: by 2002:a17:90b:2304:b0:269:46d7:f1db with SMTP id mt4-20020a17090b230400b0026946d7f1dbmr9862231pjb.32.1692727358080; Tue, 22 Aug 2023 11:02:38 -0700 (PDT) Received: from localhost ([2a00:79e1:abd:4a00:6c80:7c10:75a0:44f4]) by smtp.gmail.com with ESMTPSA id cm1-20020a17090afa0100b0026940eb686bsm9910775pjb.20.2023.08.22.11.02.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 22 Aug 2023 11:02:37 -0700 (PDT) From: Rob Clark To: dri-devel@lists.freedesktop.org Cc: linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, Rob Clark , "Rafael J. Wysocki" , Pavel Machek , Len Brown , Greg Kroah-Hartman , linux-pm@vger.kernel.org (open list:HIBERNATION (aka Software Suspend, aka swsusp)), linux-kernel@vger.kernel.org (open list) Subject: [PATCH v5 04/11] PM / QoS: Decouple request alloc from dev_pm_qos_mtx Date: Tue, 22 Aug 2023 11:01:51 -0700 Message-ID: <20230822180208.95556-5-robdclark@gmail.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230822180208.95556-1-robdclark@gmail.com> References: <20230822180208.95556-1-robdclark@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org From: Rob Clark Similar to the previous patch, move the allocation out from under dev_pm_qos_mtx, by speculatively doing the allocation and handle any race after acquiring dev_pm_qos_mtx by freeing the redundant allocation. Signed-off-by: Rob Clark --- drivers/base/power/qos.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c index 7e95760d16dc..09834f3354d7 100644 --- a/drivers/base/power/qos.c +++ b/drivers/base/power/qos.c @@ -930,8 +930,12 @@ s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev) int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val) { struct dev_pm_qos *qos = dev_pm_qos_constraints_allocate(dev); + struct dev_pm_qos_request *req = NULL; int ret = 0; + if (!qos->latency_tolerance_req) + req = kzalloc(sizeof(*req), GFP_KERNEL); + mutex_lock(&dev_pm_qos_mtx); dev_pm_qos_constraints_set(dev, qos); @@ -945,8 +949,6 @@ int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val) goto out; if (!dev->power.qos->latency_tolerance_req) { - struct dev_pm_qos_request *req; - if (val < 0) { if (val == PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT) ret = 0; @@ -954,17 +956,15 @@ int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val) ret = -EINVAL; goto out; } - req = kzalloc(sizeof(*req), GFP_KERNEL); if (!req) { ret = -ENOMEM; goto out; } ret = __dev_pm_qos_add_request(dev, req, DEV_PM_QOS_LATENCY_TOLERANCE, val); - if (ret < 0) { - kfree(req); + if (ret < 0) goto out; - } dev->power.qos->latency_tolerance_req = req; + req = NULL; } else { if (val < 0) { __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY_TOLERANCE); @@ -976,6 +976,7 @@ int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val) out: mutex_unlock(&dev_pm_qos_mtx); + kfree(req); return ret; } EXPORT_SYMBOL_GPL(dev_pm_qos_update_user_latency_tolerance);