From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D85DFC433DF for ; Wed, 24 Jun 2020 08:03:31 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A1BD7212CC for ; Wed, 24 Jun 2020 08:03:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A1BD7212CC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=chris-wilson.co.uk Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 11C196B0003; Wed, 24 Jun 2020 04:03:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0CE446B0007; Wed, 24 Jun 2020 04:03:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F26086B0008; Wed, 24 Jun 2020 04:03:30 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0244.hostedemail.com [216.40.44.244]) by kanga.kvack.org (Postfix) with ESMTP id DB8346B0003 for ; Wed, 24 Jun 2020 04:03:30 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 8ADE01EE6 for ; Wed, 24 Jun 2020 08:03:30 +0000 (UTC) X-FDA: 76963365780.28.pest65_5715c4626e42 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin28.hostedemail.com (Postfix) with ESMTP id 6825C6D68 for ; Wed, 24 Jun 2020 08:03:30 +0000 (UTC) X-HE-Tag: pest65_5715c4626e42 X-Filterd-Recvd-Size: 2919 Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by imf48.hostedemail.com (Postfix) with ESMTP for ; Wed, 24 Jun 2020 08:03:29 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from build.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 21599206-1500050 for multiple; Wed, 24 Jun 2020 09:03:20 +0100 From: Chris Wilson To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org, Chris Wilson Subject: [PATCH 2/2] drm/i915/gem: Use mmu_notifier_range_mayfail() to avoid waiting inside reclaim Date: Wed, 24 Jun 2020 09:02:48 +0100 Message-Id: <20200624080248.3701-2-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200624080248.3701-1-chris@chris-wilson.co.uk> References: <20200624080248.3701-1-chris@chris-wilson.co.uk> MIME-Version: 1.0 X-Rspamd-Queue-Id: 6825C6D68 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam01 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: The direct reclaim path may trigger the mmu_notifier callback as part of try_to_unmap_one. As this is purely an opportunitistic attempt to reclaim pages, and will be called from any allocation context under unknown conditions (that include attempting to allocate pages for the userptr object itself and subsequently trying to reclaim parts of the partially acquired object) we have to be careful never to wait on anything being held by the calling context. Since that is unknown, we have to avoid waiting from inside direct reclaim. Signed-off-by: Chris Wilson --- drivers/gpu/drm/i915/gem/i915_gem_userptr.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/dr= m/i915/gem/i915_gem_userptr.c index 9c53eb883400..72cfb91230ea 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c @@ -103,6 +103,7 @@ userptr_mn_invalidate_range_start(struct mmu_notifier= *_mn, it =3D interval_tree_iter_first(&mn->objects, range->start, end); while (it) { struct drm_i915_gem_object *obj; + unsigned int flags; =20 if (!mmu_notifier_range_blockable(range)) { ret =3D -EAGAIN; @@ -126,9 +127,12 @@ userptr_mn_invalidate_range_start(struct mmu_notifie= r *_mn, } spin_unlock(&mn->lock); =20 - ret =3D i915_gem_object_unbind(obj, - I915_GEM_OBJECT_UNBIND_ACTIVE | - I915_GEM_OBJECT_UNBIND_BARRIER); + flags =3D (I915_GEM_OBJECT_UNBIND_ACTIVE | + I915_GEM_OBJECT_UNBIND_BARRIER); + if (mmu_notifier_range_mayfail(range)) + flags =3D 0; + + ret =3D i915_gem_object_unbind(obj, flags); if (ret =3D=3D 0) ret =3D __i915_gem_object_put_pages(obj); i915_gem_object_put(obj); --=20 2.20.1