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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 8E1ECC433E0 for ; Wed, 24 Mar 2021 11:13:56 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8F047619B6 for ; Wed, 24 Mar 2021 11:13:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8F047619B6 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id ECB366E9C6; Wed, 24 Mar 2021 11:13:54 +0000 (UTC) Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6FD856E9C1 for ; Wed, 24 Mar 2021 11:13:53 +0000 (UTC) Received: by mail-wr1-x429.google.com with SMTP id b9so24030053wrt.8 for ; Wed, 24 Mar 2021 04:13:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=B1xGBVTejKcQ1HCjhzu+vENZoHeEyRx4OXc51ZX0vn0=; b=izTA58A5CUKZbKN6oP/6+IQrFctaI6k/g3XMhUNirzJrDIo0tC1zM8lbn1yKCryf3e dD0M09G7IksO4z7cGkqwxCBWxXDQWT8ZykB8gjIzcnEzuEAT/W4i3GuSN6dKc67w6/Zt y5xVvJlq1weTguNHCLZzg8Xyr3einRWkt5Fq0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=B1xGBVTejKcQ1HCjhzu+vENZoHeEyRx4OXc51ZX0vn0=; b=fLI/1B7oZ84bKAiwRxG66arFAtUMZaj0FgFdFeC7fczmMOrSUjKMVavapkMenn0+Ec OvS0S7k3u1NwynqbsW29oi2Sj0842w9hXXGBqBXd3voTTkAIPXFofj7cjKLhp2RxPwH2 e66B74osUh1lwJlojMZmmsDW4A4UvG4sWdSMpQGNbPbWZy2FZkj6ajU4RyscVQrxyKNo rQZJE+xJt64l2Ec94fq2pOQFnYcJhlcC5yFepHVPfYKyai1jZxZmkJeG5FOeqgg2uVtm gsOrAslsQgWdHI9A9KzvfpZ4H/78q7OHqGfGa9bikmbpd6Q+zm1mj46ykRS7dIIEWoER oOPg== X-Gm-Message-State: AOAM531B2M0sm5+8hx7n82/UZWunBfw/qfozE/lDrEYZSkeOK0UX7M5Z XGkeuDxSJQdbl6xNd+wt4i6bTw== X-Google-Smtp-Source: ABdhPJxHYy9DHsfXaRGydxU/umfNCzn8cC7XLhT2r0L67l+Z0STsWeX+D4iS6DNQ8PfPviRyVp113A== X-Received: by 2002:a5d:6945:: with SMTP id r5mr2824273wrw.367.1616584432087; Wed, 24 Mar 2021 04:13:52 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id p27sm2153191wmi.12.2021.03.24.04.13.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 24 Mar 2021 04:13:51 -0700 (PDT) Date: Wed, 24 Mar 2021 12:13:49 +0100 From: Daniel Vetter To: Maarten Lankhorst Message-ID: References: <20210323155059.628690-1-maarten.lankhorst@linux.intel.com> <20210323155059.628690-18-maarten.lankhorst@linux.intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210323155059.628690-18-maarten.lankhorst@linux.intel.com> X-Operating-System: Linux phenom 5.7.0-1-amd64 Subject: Re: [Intel-gfx] [PATCH v9 17/70] drm/i915: Flatten obj->mm.lock X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Thomas =?iso-8859-1?Q?Hellstr=F6m?= , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Tue, Mar 23, 2021 at 04:50:06PM +0100, Maarten Lankhorst wrote: > With userptr fixed, there is no need for all separate lockdep classes > now, and we can remove all lockdep tricks used. A trylock in the > shrinker is all we need now to flatten the locking hierarchy. > = > Signed-off-by: Maarten Lankhorst > Reviewed-by: Thomas Hellstr=F6m Minor conflict with this one here when applying, due to lack of https://lore.kernel.org/intel-gfx/20210202154318.19246-1-chris@chris-wilson= .co. It's not a bad idea, but if we do this we really should move this helper into the right headers, and ideally get linux-mm/-fs folks to ack this as a good idea. Especially Dave Chinner very much wants to be in the loop for anything that touches fs_reclaim lockdep annotations. -Daniel > --- > drivers/gpu/drm/i915/gem/i915_gem_object.c | 5 +-- > drivers/gpu/drm/i915/gem/i915_gem_object.h | 20 ++---------- > drivers/gpu/drm/i915/gem/i915_gem_pages.c | 34 ++++++++++---------- > drivers/gpu/drm/i915/gem/i915_gem_phys.c | 2 +- > drivers/gpu/drm/i915/gem/i915_gem_shrinker.c | 10 +++--- > drivers/gpu/drm/i915/gem/i915_gem_userptr.c | 2 +- > 6 files changed, 27 insertions(+), 46 deletions(-) > = > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm= /i915/gem/i915_gem_object.c > index 6083b9c14be6..821cb40f8d73 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_object.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c > @@ -62,7 +62,7 @@ void i915_gem_object_init(struct drm_i915_gem_object *o= bj, > const struct drm_i915_gem_object_ops *ops, > struct lock_class_key *key, unsigned flags) > { > - __mutex_init(&obj->mm.lock, ops->name ?: "obj->mm.lock", key); > + mutex_init(&obj->mm.lock); > = > spin_lock_init(&obj->vma.lock); > INIT_LIST_HEAD(&obj->vma.list); > @@ -86,9 +86,6 @@ void i915_gem_object_init(struct drm_i915_gem_object *o= bj, > mutex_init(&obj->mm.get_page.lock); > INIT_RADIX_TREE(&obj->mm.get_dma_page.radix, GFP_KERNEL | __GFP_NOWARN); > mutex_init(&obj->mm.get_dma_page.lock); > - > - if (IS_ENABLED(CONFIG_LOCKDEP) && i915_gem_object_is_shrinkable(obj)) > - fs_reclaim_taints_mutex(&obj->mm.lock); > } > = > /** > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm= /i915/gem/i915_gem_object.h > index b5af9c440ac5..a0e1c4ff0de4 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_object.h > +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h > @@ -372,27 +372,10 @@ void __i915_gem_object_set_pages(struct drm_i915_ge= m_object *obj, > int ____i915_gem_object_get_pages(struct drm_i915_gem_object *obj); > int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj); > = > -enum i915_mm_subclass { /* lockdep subclass for obj->mm.lock/struct_mute= x */ > - I915_MM_NORMAL =3D 0, > - /* > - * Only used by struct_mutex, when called "recursively" from > - * direct-reclaim-esque. Safe because there is only every one > - * struct_mutex in the entire system. > - */ > - I915_MM_SHRINKER =3D 1, > - /* > - * Used for obj->mm.lock when allocating pages. Safe because the object > - * isn't yet on any LRU, and therefore the shrinker can't deadlock on > - * it. As soon as the object has pages, obj->mm.lock nests within > - * fs_reclaim. > - */ > - I915_MM_GET_PAGES =3D 1, > -}; > - > static inline int __must_check > i915_gem_object_pin_pages(struct drm_i915_gem_object *obj) > { > - might_lock_nested(&obj->mm.lock, I915_MM_GET_PAGES); > + might_lock(&obj->mm.lock); > = > if (atomic_inc_not_zero(&obj->mm.pages_pin_count)) > return 0; > @@ -436,6 +419,7 @@ i915_gem_object_unpin_pages(struct drm_i915_gem_objec= t *obj) > } > = > int __i915_gem_object_put_pages(struct drm_i915_gem_object *obj); > +int __i915_gem_object_put_pages_locked(struct drm_i915_gem_object *obj); > void i915_gem_object_truncate(struct drm_i915_gem_object *obj); > void i915_gem_object_writeback(struct drm_i915_gem_object *obj); > = > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pages.c b/drivers/gpu/drm/= i915/gem/i915_gem_pages.c > index e7d7650072c5..e947d4c0da1f 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_pages.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_pages.c > @@ -114,7 +114,7 @@ int __i915_gem_object_get_pages(struct drm_i915_gem_o= bject *obj) > { > int err; > = > - err =3D mutex_lock_interruptible_nested(&obj->mm.lock, I915_MM_GET_PAGE= S); > + err =3D mutex_lock_interruptible(&obj->mm.lock); > if (err) > return err; > = > @@ -196,21 +196,13 @@ __i915_gem_object_unset_pages(struct drm_i915_gem_o= bject *obj) > return pages; > } > = > -int __i915_gem_object_put_pages(struct drm_i915_gem_object *obj) > +int __i915_gem_object_put_pages_locked(struct drm_i915_gem_object *obj) > { > struct sg_table *pages; > - int err; > = > if (i915_gem_object_has_pinned_pages(obj)) > return -EBUSY; > = > - /* May be called by shrinker from within get_pages() (on another bo) */ > - mutex_lock(&obj->mm.lock); > - if (unlikely(atomic_read(&obj->mm.pages_pin_count))) { > - err =3D -EBUSY; > - goto unlock; > - } > - > i915_gem_object_release_mmap_offset(obj); > = > /* > @@ -226,14 +218,22 @@ int __i915_gem_object_put_pages(struct drm_i915_gem= _object *obj) > * get_pages backends we should be better able to handle the > * cancellation of the async task in a more uniform manner. > */ > - if (!pages) > - pages =3D ERR_PTR(-EINVAL); > - > - if (!IS_ERR(pages)) > + if (!IS_ERR_OR_NULL(pages)) > obj->ops->put_pages(obj, pages); > = > - err =3D 0; > -unlock: > + return 0; > +} > + > +int __i915_gem_object_put_pages(struct drm_i915_gem_object *obj) > +{ > + int err; > + > + if (i915_gem_object_has_pinned_pages(obj)) > + return -EBUSY; > + > + /* May be called by shrinker from within get_pages() (on another bo) */ > + mutex_lock(&obj->mm.lock); > + err =3D __i915_gem_object_put_pages_locked(obj); > mutex_unlock(&obj->mm.lock); > = > return err; > @@ -341,7 +341,7 @@ void *i915_gem_object_pin_map(struct drm_i915_gem_obj= ect *obj, > !i915_gem_object_type_has(obj, I915_GEM_OBJECT_HAS_IOMEM)) > return ERR_PTR(-ENXIO); > = > - err =3D mutex_lock_interruptible_nested(&obj->mm.lock, I915_MM_GET_PAGE= S); > + err =3D mutex_lock_interruptible(&obj->mm.lock); > if (err) > return ERR_PTR(err); > = > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_phys.c b/drivers/gpu/drm/i= 915/gem/i915_gem_phys.c > index 06c481ff79d8..44329c435cf1 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_phys.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_phys.c > @@ -236,7 +236,7 @@ int i915_gem_object_attach_phys(struct drm_i915_gem_o= bject *obj, int align) > if (err) > return err; > = > - err =3D mutex_lock_interruptible_nested(&obj->mm.lock, I915_MM_GET_PAGE= S); > + err =3D mutex_lock_interruptible(&obj->mm.lock); > if (err) > goto err_unlock; > = > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c b/drivers/gpu/d= rm/i915/gem/i915_gem_shrinker.c > index b64a0788381f..3052ef5ad89d 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c > @@ -49,9 +49,9 @@ static bool unsafe_drop_pages(struct drm_i915_gem_objec= t *obj, > flags =3D I915_GEM_OBJECT_UNBIND_TEST; > = > if (i915_gem_object_unbind(obj, flags) =3D=3D 0) > - __i915_gem_object_put_pages(obj); > + return true; > = > - return !i915_gem_object_has_pages(obj); > + return false; > } > = > static void try_to_writeback(struct drm_i915_gem_object *obj, > @@ -200,10 +200,10 @@ i915_gem_shrink(struct drm_i915_private *i915, > = > spin_unlock_irqrestore(&i915->mm.obj_lock, flags); > = > - if (unsafe_drop_pages(obj, shrink)) { > + if (unsafe_drop_pages(obj, shrink) && > + mutex_trylock(&obj->mm.lock)) { > /* May arrive from get_pages on another bo */ > - mutex_lock(&obj->mm.lock); > - if (!i915_gem_object_has_pages(obj)) { > + if (!__i915_gem_object_put_pages_locked(obj)) { > try_to_writeback(obj, shrink); > count +=3D obj->base.size >> PAGE_SHIFT; > } > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/dr= m/i915/gem/i915_gem_userptr.c > index 1e42fbc68697..503325e74eff 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c > @@ -253,7 +253,7 @@ static int i915_gem_object_userptr_unbind(struct drm_= i915_gem_object *obj, bool > if (GEM_WARN_ON(i915_gem_object_has_pinned_pages(obj))) > return -EBUSY; > = > - mutex_lock_nested(&obj->mm.lock, I915_MM_GET_PAGES); > + mutex_lock(&obj->mm.lock); > = > pages =3D __i915_gem_object_unset_pages(obj); > if (!IS_ERR_OR_NULL(pages)) > -- = > 2.31.0 > = > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx -- = Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx