[PATCH 04/29] drm/msm: dynamically allocate the drm-msm_gem shrinker

Qi Zheng
2023-06-22T08:41:01Z

we need 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 <zhengqi.arch@bytedance.com>
---
drivers/gpu/drm/msm/msm_drv.h | 2 +-
drivers/gpu/drm/msm/msm_gem_shrinker.c | 25 ++++++++++++++-----------
2 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
index e13a8cbd61c9..4f3ba55058cd 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;

diff --git a/drivers/gpu/drm/msm/msm_gem_shrinker.c b/drivers/gpu/drm/msm/msm_gem_shrinker.c
index f38296ad8743..db7582ae1f19 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);
@@ -151,7 +149,7 @@ msm_gem_shrinker_shrink(struct drm_device *dev, unsigned long nr_to_scan)
int ret;

fs_reclaim_acquire(GFP_KERNEL);
- ret = msm_gem_shrinker_scan(&priv->shrinker, &sc);
+ ret = msm_gem_shrinker_scan(priv->shrinker, &sc);
fs_reclaim_release(GFP_KERNEL);

return ret;
@@ -213,10 +211,15 @@ msm_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr)
void 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_and_init(msm_gem_shrinker_count,
+ msm_gem_shrinker_scan, 0,
+ DEFAULT_SEEKS, 0, priv);
+ if (priv->shrinker &&
+ register_shrinker(priv->shrinker, "drm-msm_gem")) {
+ shrinker_free(priv->shrinker);
+ WARN_ON(1);
+ }

priv->vmap_notifier.notifier_call = msm_gem_shrinker_vmap;
WARN_ON(register_vmap_purge_notifier(&priv->vmap_notifier));
@@ -232,8 +235,8 @@ 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->nr_deferred) {
WARN_ON(unregister_vmap_purge_notifier(&priv->vmap_notifier));
- unregister_shrinker(&priv->shrinker);
+ unregister_and_free_shrinker(priv->shrinker);
}
}
--
2.30.2