From patchwork Fri Nov 21 08:51:58 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oded Gabbay X-Patchwork-Id: 5353531 Return-Path: X-Original-To: patchwork-dri-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id A73839F387 for ; Fri, 21 Nov 2014 08:52:14 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id DEE6120160 for ; Fri, 21 Nov 2014 08:52:13 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 1A5D62015D for ; Fri, 21 Nov 2014 08:52:13 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B92696F047; Fri, 21 Nov 2014 00:52:11 -0800 (PST) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from na01-bl2-obe.outbound.protection.outlook.com (mail-bl2on0125.outbound.protection.outlook.com [65.55.169.125]) by gabe.freedesktop.org (Postfix) with ESMTP id 5CF536F053 for ; Fri, 21 Nov 2014 00:52:10 -0800 (PST) Received: from BY2PR02CA0051.namprd02.prod.outlook.com (10.141.216.41) by CO1PR02MB205.namprd02.prod.outlook.com (10.242.165.139) with Microsoft SMTP Server (TLS) id 15.1.16.15; Fri, 21 Nov 2014 08:52:08 +0000 Received: from BY2FFO11FD046.protection.gbl (2a01:111:f400:7c0c::151) by BY2PR02CA0051.outlook.office365.com (2a01:111:e400:2c40::41) with Microsoft SMTP Server (TLS) id 15.1.26.15 via Frontend Transport; Fri, 21 Nov 2014 08:52:08 +0000 Received: from atltwp01.amd.com (165.204.84.221) by BY2FFO11FD046.mail.protection.outlook.com (10.1.15.170) with Microsoft SMTP Server id 15.1.6.13 via Frontend Transport; Fri, 21 Nov 2014 08:52:08 +0000 X-WSS-ID: 0NFDSMU-07-FJ0-02 X-M-MSG: Received: from satlvexedge02.amd.com (satlvexedge02.amd.com [10.177.96.29]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by atltwp01.amd.com (Axway MailGate 5.3.1) with ESMTPS id 22E23CAE7B6 for ; Fri, 21 Nov 2014 02:52:05 -0600 (CST) Received: from SATLEXDAG01.amd.com (10.181.40.3) by SATLVEXEDGE02.amd.com (10.177.96.29) with Microsoft SMTP Server (TLS) id 14.3.195.1; Fri, 21 Nov 2014 02:52:32 -0600 Received: from odedg-kaveri.amd.com (10.180.168.240) by SATLEXDAG01.amd.com (10.181.40.3) with Microsoft SMTP Server (TLS) id 14.3.195.1; Fri, 21 Nov 2014 03:52:04 -0500 From: Oded Gabbay To: Subject: [PATCH 10/12] amdkfd: use schedule() in sync_with_hw Date: Fri, 21 Nov 2014 10:51:58 +0200 Message-ID: <1416559920-7779-1-git-send-email-oded.gabbay@amd.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1416559111-5900-1-git-send-email-oded.gabbay@amd.com> References: <1416559111-5900-1-git-send-email-oded.gabbay@amd.com> MIME-Version: 1.0 X-Originating-IP: [10.180.168.240] X-EOPAttributedMessage: 0 X-Forefront-Antispam-Report: CIP:165.204.84.221; CTRY:US; IPV:NLI; EFV:NLI; SFV:NSPM; SFS:(10019020)(6009001)(428002)(199003)(189002)(105586002)(77096003)(62966003)(450100001)(107886001)(47776003)(102836001)(107046002)(4396001)(2351001)(92726001)(92566001)(20776003)(64706001)(106466001)(97736003)(50466002)(77156002)(46102003)(99396003)(95666004)(101416001)(229853001)(53416004)(120916001)(86362001)(44976005)(88136002)(19580395003)(68736004)(19580405001)(110136001)(76176999)(21056001)(87936001)(50226001)(31966008)(33646002)(87286001)(93916002)(89996001)(104166001)(36756003)(48376002)(84676001)(50986999); DIR:OUT; SFP:1102; SCL:1; SRVR:CO1PR02MB205; H:atltwp01.amd.com; FPR:; MLV:sfv; PTR:InfoDomainNonexistent; A:1; MX:1; LANG:en; X-Microsoft-Antispam: UriScan:; X-Microsoft-Antispam: BCL:0;PCL:0;RULEID:;SRVR:CO1PR02MB205; X-Exchange-Antispam-Report-Test: UriScan:; X-Exchange-Antispam-Report-CFA-Test: BCL:0;PCL:0;RULEID:;SRVR:CO1PR02MB205; X-Forefront-PRVS: 0402872DA1 Received-SPF: None (protection.outlook.com: amd.com does not designate permitted sender hosts) Authentication-Results: spf=none (sender IP is 165.204.84.221) smtp.mailfrom=Oded.Gabbay@amd.com; X-Exchange-Antispam-Report-CFA-Test: BCL:0;PCL:0;RULEID:;SRVR:CO1PR02MB205; X-OriginatorOrg: amd4.onmicrosoft.com X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP amdkfd uses cpu_relax() in its sync_with_hw() function. Because cpu_relax() is defined as 'REP; NOP' on x86_64, it will block the CPU from servicing IOMMU PPR requests. This may cause a deadlock, because sync_with_hw() won't be completed until the PPR request has been served. Therefore, we need to use schedule() instead of cpu_relax() as it is the minimum requirement to allow other threads to execute. Signed-off-by: Oded Gabbay --- drivers/gpu/drm/amd/amdkfd/kfd_kernel_queue.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_kernel_queue.c b/drivers/gpu/drm/amd/amdkfd/kfd_kernel_queue.c index 5055fc9..9abac48 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_kernel_queue.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_kernel_queue.c @@ -25,6 +25,7 @@ #include #include #include +#include #include "kfd_kernel_queue.h" #include "kfd_priv.h" #include "kfd_device_queue_manager.h" @@ -274,7 +275,7 @@ static int sync_with_hw(struct kernel_queue *kq, unsigned long timeout_ms) *kq->wptr_kernel, *kq->rptr_kernel); return -ETIME; } - cpu_relax(); + schedule(); } return 0;