Re: [PATCH v2 23/47] drm/msm: dynamically allocate the drm-msm_gem shrinker

2023-07-26 Thread Qi Zheng




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(>shrinker, );
+    if (priv->shrinker)
+    ret = msm_gem_shrinker_scan(priv->shrinker, );
  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(>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(>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) {
  

Re: [PATCH v2 23/47] drm/msm: dynamically allocate the drm-msm_gem shrinker

2023-07-26 Thread Muchun Song




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(>shrinker, );
+   if (priv->shrinker)
+   ret = msm_gem_shrinker_scan(priv->shrinker, );
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(>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(>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 

[PATCH v2 23/47] drm/msm: dynamically allocate the drm-msm_gem shrinker

2023-07-24 Thread Qi Zheng
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 
---
 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(>shrinker, );
+   if (priv->shrinker)
+   ret = msm_gem_shrinker_scan(priv->shrinker, );
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(>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(>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(>vmap_notifier));
-   unregister_shrinker(>shrinker);
+