From patchwork Wed Oct 9 10:28:48 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Hellstrom X-Patchwork-Id: 3008111 Return-Path: X-Original-To: patchwork-dri-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 245ABBF924 for ; Wed, 9 Oct 2013 10:29:17 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0214C20170 for ; Wed, 9 Oct 2013 10:29:16 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 7D6A92014A for ; Wed, 9 Oct 2013 10:29:14 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6A87BE771A for ; Wed, 9 Oct 2013 03:29:14 -0700 (PDT) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from smtp-outbound-1.vmware.com (smtp-outbound-1.vmware.com [208.91.2.12]) by gabe.freedesktop.org (Postfix) with ESMTP id EBCAEE762F for ; Wed, 9 Oct 2013 03:29:01 -0700 (PDT) Received: from sc9-mailhost1.vmware.com (sc9-mailhost1.vmware.com [10.113.161.71]) by smtp-outbound-1.vmware.com (Postfix) with ESMTP id 656992B070; Wed, 9 Oct 2013 03:29:01 -0700 (PDT) Received: from zcs-prod-ext-mta-2.vmware.com (zcs-prod-ext-mta-2.vmware.com [10.113.62.224]) by sc9-mailhost1.vmware.com (Postfix) with ESMTP id 617AC183B2; Wed, 9 Oct 2013 03:29:01 -0700 (PDT) Received: from zcs-prod-ext-mta-2.vmware.com (localhost.localdomain [127.0.0.1]) by zcs-prod-ext-mta-2.vmware.com (Postfix) with ESMTP id 7C117C0059; Wed, 9 Oct 2013 03:29:13 -0700 (PDT) Received: from ubuntu.localdomain (zimbra-prod-ext-proxy-vip.vmware.com [10.113.63.87]) by zcs-prod-ext-mta-2.vmware.com (Postfix) with ESMTPSA; Wed, 9 Oct 2013 03:29:11 -0700 (PDT) From: Thomas Hellstrom To: airlied@redhat.com, airlied@gmail.com Subject: [PATCH RFC] drm/ttm: Allow vm fault retries Date: Wed, 9 Oct 2013 03:28:48 -0700 Message-Id: <1381314528-21732-1-git-send-email-thellstrom@vmware.com> X-Mailer: git-send-email 1.7.10.4 Cc: Thomas Hellstrom , dri-devel@lists.freedesktop.org X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: dri-devel-bounces+patchwork-dri-devel=patchwork.kernel.org@lists.freedesktop.org Errors-To: dri-devel-bounces+patchwork-dri-devel=patchwork.kernel.org@lists.freedesktop.org X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, 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 Make use of the FAULT_FLAG_ALLOW_RETRY flag to allow dropping the mmap_sem while waiting for bo idle. FAULT_FLAG_ALLOW_RETRY appears to be primarily designed for disk waits but should work just as fine for GPU waits.. Only compile-tested so far pending comments. Signed-off-by: Thomas Hellstrom --- drivers/gpu/drm/ttm/ttm_bo_vm.c | 61 ++++++++++++++++++++++++++++++--------- 1 file changed, 48 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c index 1006c15..6510ce2 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c @@ -41,6 +41,50 @@ #define TTM_BO_VM_NUM_PREFAULT 16 +static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo, + struct vm_area_struct *vma, + struct vm_fault *vmf) +{ + struct ttm_bo_device *bdev = bo->bdev; + int ret = 0; + + spin_lock(&bdev->fence_lock); + if (likely(!test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags))) + goto out_unlock; + + /* + * Quick non-stalling check for idle. + */ + ret = ttm_bo_wait(bo, false, false, true); + if (likely(ret == 0)) + goto out_unlock; + + /* + * If possible, avoid waiting for GPU with mmap_sem + * held. + */ + if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) { + ret = VM_FAULT_RETRY; + if (vmf->flags & FAULT_FLAG_RETRY_NOWAIT) + goto out_unlock; + + up_read(&vma->vm_mm->mmap_sem); + (void) ttm_bo_wait(bo, false, true, false); + goto out_unlock; + } + + /* + * Ordinary wait. + */ + ret = ttm_bo_wait(bo, false, true, false); + if (unlikely(ret != 0)) + ret = (ret == -ERESTARTSYS) ? VM_FAULT_SIGBUS : + VM_FAULT_NOPAGE; +out_unlock: + spin_unlock(&bdev->fence_lock); + return ret; +} + static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) { struct ttm_buffer_object *bo = (struct ttm_buffer_object *) @@ -91,19 +135,10 @@ static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) * Wait for buffer data in transit, due to a pipelined * move. */ - - spin_lock(&bdev->fence_lock); - if (test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)) { - ret = ttm_bo_wait(bo, false, true, false); - spin_unlock(&bdev->fence_lock); - if (unlikely(ret != 0)) { - retval = (ret != -ERESTARTSYS) ? - VM_FAULT_SIGBUS : VM_FAULT_NOPAGE; - goto out_unlock; - } - } else - spin_unlock(&bdev->fence_lock); - + retval = ttm_bo_vm_fault_idle(bo, vma, vmf); + if (unlikely(retval != 0)) + goto out_unlock; + ret = ttm_mem_io_lock(man, true); if (unlikely(ret != 0)) { retval = VM_FAULT_NOPAGE;