Re: [PATCH v4 19/48] rcu: dynamically allocate the rcu-kfree shrinker

[Muchun Song]

> On Aug 7, 2023, at 19:09, Qi Zheng  wrote:
> 
> Use new APIs to dynamically allocate the rcu-kfree shrinker.
> 
> Signed-off-by: Qi Zheng 

Reviewed-by: Muchun Song 

Re: [PATCH v4 19/48] rcu: dynamically allocate the rcu-kfree shrinker

[Joel Fernandes]

On Mon, Aug 7, 2023 at 7:17 AM Qi Zheng  wrote:
>
> Use new APIs to dynamically allocate the rcu-kfree shrinker.
>
> Signed-off-by: Qi Zheng 

For RCU:
Reviewed-by: Joel Fernandes (Google) 

thanks,

- Joel


> ---
>  kernel/rcu/tree.c | 22 +-
>  1 file changed, 13 insertions(+), 9 deletions(-)
>
> diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
> index 7c79480bfaa0..3b20fc46c514 100644
> --- a/kernel/rcu/tree.c
> +++ b/kernel/rcu/tree.c
> @@ -3449,13 +3449,6 @@ kfree_rcu_shrink_scan(struct shrinker *shrink, struct 
> shrink_control *sc)
> return freed == 0 ? SHRINK_STOP : freed;
>  }
>
> -static struct shrinker kfree_rcu_shrinker = {
> -   .count_objects = kfree_rcu_shrink_count,
> -   .scan_objects = kfree_rcu_shrink_scan,
> -   .batch = 0,
> -   .seeks = DEFAULT_SEEKS,
> -};
> -
>  void __init kfree_rcu_scheduler_running(void)
>  {
> int cpu;
> @@ -4931,6 +4924,7 @@ static void __init kfree_rcu_batch_init(void)
>  {
> int cpu;
> int i, j;
> +   struct shrinker *kfree_rcu_shrinker;
>
> /* Clamp it to [0:100] seconds interval. */
> if (rcu_delay_page_cache_fill_msec < 0 ||
> @@ -4962,8 +4956,18 @@ static void __init kfree_rcu_batch_init(void)
> INIT_DELAYED_WORK(>page_cache_work, 
> fill_page_cache_func);
> krcp->initialized = true;
> }
> -   if (register_shrinker(_rcu_shrinker, "rcu-kfree"))
> -   pr_err("Failed to register kfree_rcu() shrinker!\n");
> +
> +   kfree_rcu_shrinker = shrinker_alloc(0, "rcu-kfree");
> +   if (!kfree_rcu_shrinker) {
> +   pr_err("Failed to allocate kfree_rcu() shrinker!\n");
> +   return;
> +   }
> +
> +   kfree_rcu_shrinker->count_objects = kfree_rcu_shrink_count;
> +   kfree_rcu_shrinker->scan_objects = kfree_rcu_shrink_scan;
> +   kfree_rcu_shrinker->seeks = DEFAULT_SEEKS;
> +
> +   shrinker_register(kfree_rcu_shrinker);
>  }
>
>  void __init rcu_init(void)
> --
> 2.30.2
>

[PATCH v4 19/48] rcu: dynamically allocate the rcu-kfree shrinker

[Qi Zheng]

Use new APIs to dynamically allocate the rcu-kfree shrinker.

Signed-off-by: Qi Zheng 
---
 kernel/rcu/tree.c | 22 +-
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 7c79480bfaa0..3b20fc46c514 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3449,13 +3449,6 @@ kfree_rcu_shrink_scan(struct shrinker *shrink, struct 
shrink_control *sc)
return freed == 0 ? SHRINK_STOP : freed;
 }
 
-static struct shrinker kfree_rcu_shrinker = {
-   .count_objects = kfree_rcu_shrink_count,
-   .scan_objects = kfree_rcu_shrink_scan,
-   .batch = 0,
-   .seeks = DEFAULT_SEEKS,
-};
-
 void __init kfree_rcu_scheduler_running(void)
 {
int cpu;
@@ -4931,6 +4924,7 @@ static void __init kfree_rcu_batch_init(void)
 {
int cpu;
int i, j;
+   struct shrinker *kfree_rcu_shrinker;
 
/* Clamp it to [0:100] seconds interval. */
if (rcu_delay_page_cache_fill_msec < 0 ||
@@ -4962,8 +4956,18 @@ static void __init kfree_rcu_batch_init(void)
INIT_DELAYED_WORK(>page_cache_work, fill_page_cache_func);
krcp->initialized = true;
}
-   if (register_shrinker(_rcu_shrinker, "rcu-kfree"))
-   pr_err("Failed to register kfree_rcu() shrinker!\n");
+
+   kfree_rcu_shrinker = shrinker_alloc(0, "rcu-kfree");
+   if (!kfree_rcu_shrinker) {
+   pr_err("Failed to allocate kfree_rcu() shrinker!\n");
+   return;
+   }
+
+   kfree_rcu_shrinker->count_objects = kfree_rcu_shrink_count;
+   kfree_rcu_shrinker->scan_objects = kfree_rcu_shrink_scan;
+   kfree_rcu_shrinker->seeks = DEFAULT_SEEKS;
+
+   shrinker_register(kfree_rcu_shrinker);
 }
 
 void __init rcu_init(void)
-- 
2.30.2