From patchwork Fri Oct 12 08:56:56 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sharat Masetty X-Patchwork-Id: 10638125 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 16176933 for ; Fri, 12 Oct 2018 08:57:23 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0632F2B798 for ; Fri, 12 Oct 2018 08:57:23 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EE48C2B79B; Fri, 12 Oct 2018 08:57:22 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id B14302B798 for ; Fri, 12 Oct 2018 08:57:22 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0190B6E458; Fri, 12 Oct 2018 08:57:21 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from smtp.codeaurora.org (smtp.codeaurora.org [198.145.29.96]) by gabe.freedesktop.org (Postfix) with ESMTPS id 822886E454; Fri, 12 Oct 2018 08:57:17 +0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 6DF9160BF7; Fri, 12 Oct 2018 08:57:17 +0000 (UTC) Received: from smasetty-linux.qualcomm.com (blr-c-bdr-fw-01_globalnat_allzones-outside.qualcomm.com [103.229.19.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: smasetty@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id AA7A46063F; Fri, 12 Oct 2018 08:57:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org AA7A46063F From: Sharat Masetty To: freedreno@lists.freedesktop.org Subject: [PATCH 3/3] drm/msm: Fix task dump in gpu recovery Date: Fri, 12 Oct 2018 14:26:56 +0530 Message-Id: <1539334616-11723-4-git-send-email-smasetty@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1539334616-11723-1-git-send-email-smasetty@codeaurora.org> References: <1539334616-11723-1-git-send-email-smasetty@codeaurora.org> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arm-msm@vger.kernel.org, Sharat Masetty , dri-devel@lists.freedesktop.org MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP The current recovery code gets a pointer to the task struct and does a few things all within the rcu_read_lock. This puts constraints on the types of gfp flags that can be used within the rcu lock. This patch instead gets a reference to the task within the rcu lock and releases the lock immediately, this way the task stays afloat until we need it and we also get to use the desired gfp flags. Signed-off-by: Sharat Masetty --- drivers/gpu/drm/msm/msm_gpu.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c index da63d3d..ca573f6 100644 --- a/drivers/gpu/drm/msm/msm_gpu.c +++ b/drivers/gpu/drm/msm/msm_gpu.c @@ -438,10 +438,9 @@ static void recover_worker(struct work_struct *work) if (submit) { struct task_struct *task; - rcu_read_lock(); - task = pid_task(submit->pid, PIDTYPE_PID); + task = get_pid_task(submit->pid, PIDTYPE_PID); if (task) { - comm = kstrdup(task->comm, GFP_ATOMIC); + comm = kstrdup(task->comm, GFP_KERNEL); /* * So slightly annoying, in other paths like @@ -454,10 +453,10 @@ static void recover_worker(struct work_struct *work) * about the submit going away. */ mutex_unlock(&dev->struct_mutex); - cmd = kstrdup_quotable_cmdline(task, GFP_ATOMIC); + cmd = kstrdup_quotable_cmdline(task, GFP_KERNEL); + put_task_struct(task); mutex_lock(&dev->struct_mutex); } - rcu_read_unlock(); if (comm && cmd) { dev_err(dev->dev, "%s: offending task: %s (%s)\n",