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 <[email protected]>
---
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) {
+ 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);
}
}
--
2.30.2
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 <[email protected]>
Reviewed-by: Muchun Song <[email protected]>
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);
> }
> }
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 <[email protected]>
>
> Reviewed-by: Muchun Song <[email protected]>
>
> 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);
>> }
>> }
>