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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 097FFC00528 for ; Wed, 26 Jul 2023 07:26:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232640AbjGZH0W (ORCPT ); Wed, 26 Jul 2023 03:26:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231140AbjGZHZq (ORCPT ); Wed, 26 Jul 2023 03:25:46 -0400 Received: from out-21.mta1.migadu.com (out-21.mta1.migadu.com [IPv6:2001:41d0:203:375::15]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B798A4483 for ; Wed, 26 Jul 2023 00:24:24 -0700 (PDT) Message-ID: <17de3f5b-3bef-be38-9801-0e84cfe8539b@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1690356262; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nTTDffXkzxVXBy4JmC8uLINROt4TIYQk3fp5u25NUNM=; b=BnM6ObbVvlHjNT0EQ9FNfJjw5uDAlrCLhNEcIu2YqjXKf/vGuoud+hHft88ZtRNtDuEwCg tBOK3Iz/LamlBXXb/s2VBKik1ft+6SPkGLcP8h8g11eIlgemJmkdkTnX+9qLAUoZF66N+E FHLnBM7v5jm+QRNUOfsvfgruR8wkbzM= Date: Wed, 26 Jul 2023 15:24:02 +0800 MIME-Version: 1.0 Subject: Re: [PATCH v2 23/47] drm/msm: dynamically allocate the drm-msm_gem shrinker To: Qi Zheng Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org, linux-erofs@lists.ozlabs.org, linux-f2fs-devel@lists.sourceforge.net, cluster-devel@redhat.com, linux-nfs@vger.kernel.org, linux-mtd@lists.infradead.org, rcu@vger.kernel.org, netdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, dm-devel@redhat.com, linux-raid@vger.kernel.org, linux-bcache@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, linux-btrfs@vger.kernel.org, akpm@linux-foundation.org, david@fromorbit.com, tkhai@ya.ru, vbabka@suse.cz, roman.gushchin@linux.dev, djwong@kernel.org, brauner@kernel.org, paulmck@kernel.org, tytso@mit.edu, steven.price@arm.com, cel@kernel.org, senozhatsky@chromium.org, yujie.liu@intel.com, gregkh@linuxfoundation.org References: <20230724094354.90817-1-zhengqi.arch@bytedance.com> <20230724094354.90817-24-zhengqi.arch@bytedance.com> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Muchun Song In-Reply-To: <20230724094354.90817-24-zhengqi.arch@bytedance.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 2023/7/24 17:43, Qi Zheng wrote: > In preparation for implementing lockless slab shrink, use new APIs to > dynamically allocate the drm-msm_gem shrinker, so that it can be freed > asynchronously using kfree_rcu(). Then it doesn't need to wait for RCU > read-side critical section when releasing the struct msm_drm_private. > > Signed-off-by: Qi Zheng Reviewed-by: Muchun Song A nit bellow. > --- > drivers/gpu/drm/msm/msm_drv.c | 4 ++- > drivers/gpu/drm/msm/msm_drv.h | 4 +-- > drivers/gpu/drm/msm/msm_gem_shrinker.c | 36 ++++++++++++++++---------- > 3 files changed, 28 insertions(+), 16 deletions(-) > > diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c > index 891eff8433a9..7f6933be703f 100644 > --- a/drivers/gpu/drm/msm/msm_drv.c > +++ b/drivers/gpu/drm/msm/msm_drv.c > @@ -461,7 +461,9 @@ static int msm_drm_init(struct device *dev, const struct drm_driver *drv) > if (ret) > goto err_msm_uninit; > > - msm_gem_shrinker_init(ddev); > + ret = msm_gem_shrinker_init(ddev); > + if (ret) > + goto err_msm_uninit; > > if (priv->kms_init) { > ret = priv->kms_init(ddev); > diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h > index e13a8cbd61c9..84523d4a1e58 100644 > --- a/drivers/gpu/drm/msm/msm_drv.h > +++ b/drivers/gpu/drm/msm/msm_drv.h > @@ -217,7 +217,7 @@ struct msm_drm_private { > } vram; > > struct notifier_block vmap_notifier; > - struct shrinker shrinker; > + struct shrinker *shrinker; > > struct drm_atomic_state *pm_state; > > @@ -279,7 +279,7 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data, > unsigned long msm_gem_shrinker_shrink(struct drm_device *dev, unsigned long nr_to_scan); > #endif > > -void msm_gem_shrinker_init(struct drm_device *dev); > +int msm_gem_shrinker_init(struct drm_device *dev); > void msm_gem_shrinker_cleanup(struct drm_device *dev); > > int msm_gem_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma); > diff --git a/drivers/gpu/drm/msm/msm_gem_shrinker.c b/drivers/gpu/drm/msm/msm_gem_shrinker.c > index f38296ad8743..7daab1298c11 100644 > --- a/drivers/gpu/drm/msm/msm_gem_shrinker.c > +++ b/drivers/gpu/drm/msm/msm_gem_shrinker.c > @@ -34,8 +34,7 @@ static bool can_block(struct shrink_control *sc) > static unsigned long > msm_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc) > { > - struct msm_drm_private *priv = > - container_of(shrinker, struct msm_drm_private, shrinker); > + struct msm_drm_private *priv = shrinker->private_data; > unsigned count = priv->lru.dontneed.count; > > if (can_swap()) > @@ -100,8 +99,7 @@ active_evict(struct drm_gem_object *obj) > static unsigned long > msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc) > { > - struct msm_drm_private *priv = > - container_of(shrinker, struct msm_drm_private, shrinker); > + struct msm_drm_private *priv = shrinker->private_data; > struct { > struct drm_gem_lru *lru; > bool (*shrink)(struct drm_gem_object *obj); > @@ -148,10 +146,11 @@ msm_gem_shrinker_shrink(struct drm_device *dev, unsigned long nr_to_scan) > struct shrink_control sc = { > .nr_to_scan = nr_to_scan, > }; > - int ret; > + unsigned long ret = SHRINK_STOP; > > fs_reclaim_acquire(GFP_KERNEL); > - ret = msm_gem_shrinker_scan(&priv->shrinker, &sc); > + if (priv->shrinker) > + ret = msm_gem_shrinker_scan(priv->shrinker, &sc); > fs_reclaim_release(GFP_KERNEL); > > return ret; > @@ -210,16 +209,27 @@ msm_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr) > * > * This function registers and sets up the msm shrinker. > */ > -void msm_gem_shrinker_init(struct drm_device *dev) > +int msm_gem_shrinker_init(struct drm_device *dev) > { > struct msm_drm_private *priv = dev->dev_private; > - priv->shrinker.count_objects = msm_gem_shrinker_count; > - priv->shrinker.scan_objects = msm_gem_shrinker_scan; > - priv->shrinker.seeks = DEFAULT_SEEKS; > - WARN_ON(register_shrinker(&priv->shrinker, "drm-msm_gem")); > + > + priv->shrinker = shrinker_alloc(0, "drm-msm_gem"); > + if (!priv->shrinker) { Just "if (WARN_ON(!priv->shrinker))" > + WARN_ON(1); > + return -ENOMEM; > + } > + > + priv->shrinker->count_objects = msm_gem_shrinker_count; > + priv->shrinker->scan_objects = msm_gem_shrinker_scan; > + priv->shrinker->seeks = DEFAULT_SEEKS; > + priv->shrinker->private_data = priv; > + > + shrinker_register(priv->shrinker); > > priv->vmap_notifier.notifier_call = msm_gem_shrinker_vmap; > WARN_ON(register_vmap_purge_notifier(&priv->vmap_notifier)); > + > + return 0; > } > > /** > @@ -232,8 +242,8 @@ void msm_gem_shrinker_cleanup(struct drm_device *dev) > { > struct msm_drm_private *priv = dev->dev_private; > > - if (priv->shrinker.nr_deferred) { > + if (priv->shrinker) { > WARN_ON(unregister_vmap_purge_notifier(&priv->vmap_notifier)); > - unregister_shrinker(&priv->shrinker); > + shrinker_unregister(priv->shrinker); > } > }