From patchwork Wed Jan 23 22:23:14 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jerome Glisse X-Patchwork-Id: 10778007 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 7901B1390 for ; Wed, 23 Jan 2019 22:23:55 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 68B0C2C4E4 for ; Wed, 23 Jan 2019 22:23:55 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5CD302C500; Wed, 23 Jan 2019 22:23:55 +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 EAAFD2C4E4 for ; Wed, 23 Jan 2019 22:23:54 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BCB6A6F04D; Wed, 23 Jan 2019 22:23:53 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by gabe.freedesktop.org (Postfix) with ESMTPS id AA1516F04D for ; Wed, 23 Jan 2019 22:23:52 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 067D8432C1; Wed, 23 Jan 2019 22:23:52 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-120-127.rdu2.redhat.com [10.10.120.127]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5CF0E5D965; Wed, 23 Jan 2019 22:23:49 +0000 (UTC) From: jglisse@redhat.com To: linux-mm@kvack.org Subject: [PATCH v4 8/9] gpu/drm/i915: optimize out the case when a range is updated to read only Date: Wed, 23 Jan 2019 17:23:14 -0500 Message-Id: <20190123222315.1122-9-jglisse@redhat.com> In-Reply-To: <20190123222315.1122-1-jglisse@redhat.com> References: <20190123222315.1122-1-jglisse@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Wed, 23 Jan 2019 22:23:52 +0000 (UTC) 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: Ralph Campbell , Jan Kara , Arnd Bergmann , kvm@vger.kernel.org, Matthew Wilcox , linux-rdma@vger.kernel.org, John Hubbard , Felix Kuehling , =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= , Dan Williams , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Michal Hocko , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Jason Gunthorpe , Ross Zwisler , linux-fsdevel@vger.kernel.org, Paolo Bonzini , Andrew Morton , =?utf-8?q?Christian_K=C3=B6nig?= Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Jérôme Glisse When range of virtual address is updated read only and corresponding user ptr object are already read only it is pointless to do anything. Optimize this case out. Signed-off-by: Jérôme Glisse Cc: Christian König Cc: Jan Kara Cc: Felix Kuehling Cc: Jason Gunthorpe Cc: Andrew Morton Cc: Matthew Wilcox Cc: Ross Zwisler Cc: Dan Williams Cc: Paolo Bonzini Cc: Radim Krčmář Cc: Michal Hocko Cc: Ralph Campbell Cc: John Hubbard Cc: kvm@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Cc: linux-rdma@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Cc: Arnd Bergmann --- drivers/gpu/drm/i915/i915_gem_userptr.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_gem_userptr.c b/drivers/gpu/drm/i915/i915_gem_userptr.c index 9558582c105e..23330ac3d7ea 100644 --- a/drivers/gpu/drm/i915/i915_gem_userptr.c +++ b/drivers/gpu/drm/i915/i915_gem_userptr.c @@ -59,6 +59,7 @@ struct i915_mmu_object { struct interval_tree_node it; struct list_head link; struct work_struct work; + bool read_only; bool attached; }; @@ -119,6 +120,7 @@ static int i915_gem_userptr_mn_invalidate_range_start(struct mmu_notifier *_mn, container_of(_mn, struct i915_mmu_notifier, mn); struct i915_mmu_object *mo; struct interval_tree_node *it; + bool update_to_read_only; LIST_HEAD(cancelled); unsigned long end; @@ -128,6 +130,8 @@ static int i915_gem_userptr_mn_invalidate_range_start(struct mmu_notifier *_mn, /* interval ranges are inclusive, but invalidate range is exclusive */ end = range->end - 1; + update_to_read_only = mmu_notifier_range_update_to_read_only(range); + spin_lock(&mn->lock); it = interval_tree_iter_first(&mn->objects, range->start, end); while (it) { @@ -145,6 +149,17 @@ static int i915_gem_userptr_mn_invalidate_range_start(struct mmu_notifier *_mn, * object if it is not in the process of being destroyed. */ mo = container_of(it, struct i915_mmu_object, it); + + /* + * If it is already read only and we are updating to + * read only then we do not need to change anything. + * So save time and skip this one. + */ + if (update_to_read_only && mo->read_only) { + it = interval_tree_iter_next(it, range->start, end); + continue; + } + if (kref_get_unless_zero(&mo->obj->base.refcount)) queue_work(mn->wq, &mo->work); @@ -270,6 +285,7 @@ i915_gem_userptr_init__mmu_notifier(struct drm_i915_gem_object *obj, mo->mn = mn; mo->obj = obj; mo->it.start = obj->userptr.ptr; + mo->read_only = i915_gem_object_is_readonly(obj); mo->it.last = obj->userptr.ptr + obj->base.size - 1; INIT_WORK(&mo->work, cancel_userptr);