From mboxrd@z Thu Jan 1 00:00:00 1970 From: Qi Zheng Date: Wed, 26 Jul 2023 17:31:14 +0800 Subject: [Cluster-devel] [PATCH v2 23/47] drm/msm: dynamically allocate the drm-msm_gem shrinker In-Reply-To: <17de3f5b-3bef-be38-9801-0e84cfe8539b@linux.dev> References: <20230724094354.90817-1-zhengqi.arch@bytedance.com> <20230724094354.90817-24-zhengqi.arch@bytedance.com> <17de3f5b-3bef-be38-9801-0e84cfe8539b@linux.dev> Message-ID: List-Id: To: cluster-devel.redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On 2023/7/26 15:24, Muchun Song wrote: > > > 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))" As suggested by Steven Pric in patch #24, this warning is unnecessary, so I will remove it in the next version. > >> +??????? 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); >> ????? } >> ? } >