[PATCH 05/29] drm/panfrost: dynamically allocate the drm-panfrost shrinker

Qi Zheng
2023-06-22T08:41:11Z

we need to dynamically allocate the drm-panfrost 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 panfrost_device.

Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
---
drivers/gpu/drm/panfrost/panfrost_device.h | 2 +-
.../gpu/drm/panfrost/panfrost_gem_shrinker.c | 24 ++++++++++---------
2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h
index b0126b9fbadc..e667e5689353 100644
--- a/drivers/gpu/drm/panfrost/panfrost_device.h
+++ b/drivers/gpu/drm/panfrost/panfrost_device.h
@@ -118,7 +118,7 @@ struct panfrost_device {

struct mutex shrinker_lock;
struct list_head shrinker_list;
- struct shrinker shrinker;
+ struct shrinker *shrinker;

struct panfrost_devfreq pfdevfreq;
};
diff --git a/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c b/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c
index bf0170782f25..2a5513eb9e1f 100644
--- a/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c
+++ b/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c
@@ -18,8 +18,7 @@
static unsigned long
panfrost_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc)
{
- struct panfrost_device *pfdev =
- container_of(shrinker, struct panfrost_device, shrinker);
+ struct panfrost_device *pfdev = shrinker->private_data;
struct drm_gem_shmem_object *shmem;
unsigned long count = 0;

@@ -65,8 +64,7 @@ static bool panfrost_gem_purge(struct drm_gem_object *obj)
static unsigned long
panfrost_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
{
- struct panfrost_device *pfdev =
- container_of(shrinker, struct panfrost_device, shrinker);
+ struct panfrost_device *pfdev = shrinker->private_data;
struct drm_gem_shmem_object *shmem, *tmp;
unsigned long freed = 0;

@@ -100,10 +98,15 @@ panfrost_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
void panfrost_gem_shrinker_init(struct drm_device *dev)
{
struct panfrost_device *pfdev = dev->dev_private;
- pfdev->shrinker.count_objects = panfrost_gem_shrinker_count;
- pfdev->shrinker.scan_objects = panfrost_gem_shrinker_scan;
- pfdev->shrinker.seeks = DEFAULT_SEEKS;
- WARN_ON(register_shrinker(&pfdev->shrinker, "drm-panfrost"));
+
+ pfdev->shrinker = shrinker_alloc_and_init(panfrost_gem_shrinker_count,
+ panfrost_gem_shrinker_scan, 0,
+ DEFAULT_SEEKS, 0, pfdev);
+ if (pfdev->shrinker &&
+ register_shrinker(pfdev->shrinker, "drm-panfrost")) {
+ shrinker_free(pfdev->shrinker);
+ WARN_ON(1);
+ }
}

/**
@@ -116,7 +119,6 @@ void panfrost_gem_shrinker_cleanup(struct drm_device *dev)
{
struct panfrost_device *pfdev = dev->dev_private;

- if (pfdev->shrinker.nr_deferred) {
- unregister_shrinker(&pfdev->shrinker);
- }
+ if (pfdev->shrinker->nr_deferred)
+ unregister_and_free_shrinker(pfdev->shrinker);
}
--
2.30.2