[PATCH] srcu: refactor __srcu_read_(un)lock_lite() declarations

[PATCH] srcu: refactor __srcu_read_(un)lock_lite() declarations

[Masahiro Yamada]

For CONFIG_TREE_SRCU, __srcu_read_(un)lock_lite() are defined as static
inline functions in <linux/srcutree.h>. The later function declarations
are redundant.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 include/linux/srcu.h     | 9 ++-------
 include/linux/srcutree.h | 4 ++--
 2 files changed, 4 insertions(+), 9 deletions(-)

diff --git a/include/linux/srcu.h b/include/linux/srcu.h
index 08339eb8a01c..314f0bca6eb7 100644
--- a/include/linux/srcu.h
+++ b/include/linux/srcu.h
@@ -45,6 +45,8 @@ int init_srcu_struct(struct srcu_struct *ssp);
 
 #ifdef CONFIG_TINY_SRCU
 #include <linux/srcutiny.h>
+#define __srcu_read_lock_lite __srcu_read_lock
+#define __srcu_read_unlock_lite __srcu_read_unlock
 #elif defined(CONFIG_TREE_SRCU)
 #include <linux/srcutree.h>
 #else
@@ -56,13 +58,6 @@ void call_srcu(struct srcu_struct *ssp, struct rcu_head *head,
 void cleanup_srcu_struct(struct srcu_struct *ssp);
 int __srcu_read_lock(struct srcu_struct *ssp) __acquires(ssp);
 void __srcu_read_unlock(struct srcu_struct *ssp, int idx) __releases(ssp);
-#ifdef CONFIG_TINY_SRCU
-#define __srcu_read_lock_lite __srcu_read_lock
-#define __srcu_read_unlock_lite __srcu_read_unlock
-#else // #ifdef CONFIG_TINY_SRCU
-int __srcu_read_lock_lite(struct srcu_struct *ssp) __acquires(ssp);
-void __srcu_read_unlock_lite(struct srcu_struct *ssp, int idx) __releases(ssp);
-#endif // #else // #ifdef CONFIG_TINY_SRCU
 void synchronize_srcu(struct srcu_struct *ssp);
 
 #define SRCU_GET_STATE_COMPLETED 0x1
diff --git a/include/linux/srcutree.h b/include/linux/srcutree.h
index 490aeecc6bb4..16a7d631c185 100644
--- a/include/linux/srcutree.h
+++ b/include/linux/srcutree.h
@@ -219,7 +219,7 @@ void srcu_torture_stats_print(struct srcu_struct *ssp, char *tt, char *tf);
  * or because it is a read-modify-write atomic operation, depending on
  * the whims of the architecture.
  */
-static inline int __srcu_read_lock_lite(struct srcu_struct *ssp)
+static inline int __srcu_read_lock_lite(struct srcu_struct *ssp) __acquires(ssp)
 {
 	int idx;
 
@@ -241,7 +241,7 @@ static inline int __srcu_read_lock_lite(struct srcu_struct *ssp)
  * or because it is a read-modify-write atomic operation, depending on
  * the whims of the architecture.
  */
-static inline void __srcu_read_unlock_lite(struct srcu_struct *ssp, int idx)
+static inline void __srcu_read_unlock_lite(struct srcu_struct *ssp, int idx) __releases(ssp)
 {
 	barrier();  /* Avoid leaking the critical section. */
 	this_cpu_inc(ssp->sda->srcu_unlock_count[idx].counter);  /* Z */
-- 
2.43.0

Re: [PATCH] srcu: refactor __srcu_read_(un)lock_lite() declarations

[Paul E. McKenney]

On Tue, Jan 14, 2025 at 07:52:13PM +0900, Masahiro Yamada wrote:
> For CONFIG_TREE_SRCU, __srcu_read_(un)lock_lite() are defined as static
> inline functions in <linux/srcutree.h>. The later function declarations
> are redundant.
> 
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Hello, Masahiro, and thank you for the patch!

This part of the code has seen quite a bit of churn over the past month
or so.  So could you please rebase this patch on top of my -rcu tree's
"dev" branch?

git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git

							Thanx, Paul

> ---
> 
>  include/linux/srcu.h     | 9 ++-------
>  include/linux/srcutree.h | 4 ++--
>  2 files changed, 4 insertions(+), 9 deletions(-)
> 
> diff --git a/include/linux/srcu.h b/include/linux/srcu.h
> index 08339eb8a01c..314f0bca6eb7 100644
> --- a/include/linux/srcu.h
> +++ b/include/linux/srcu.h
> @@ -45,6 +45,8 @@ int init_srcu_struct(struct srcu_struct *ssp);
>  
>  #ifdef CONFIG_TINY_SRCU
>  #include <linux/srcutiny.h>
> +#define __srcu_read_lock_lite __srcu_read_lock
> +#define __srcu_read_unlock_lite __srcu_read_unlock
>  #elif defined(CONFIG_TREE_SRCU)
>  #include <linux/srcutree.h>
>  #else
> @@ -56,13 +58,6 @@ void call_srcu(struct srcu_struct *ssp, struct rcu_head *head,
>  void cleanup_srcu_struct(struct srcu_struct *ssp);
>  int __srcu_read_lock(struct srcu_struct *ssp) __acquires(ssp);
>  void __srcu_read_unlock(struct srcu_struct *ssp, int idx) __releases(ssp);
> -#ifdef CONFIG_TINY_SRCU
> -#define __srcu_read_lock_lite __srcu_read_lock
> -#define __srcu_read_unlock_lite __srcu_read_unlock
> -#else // #ifdef CONFIG_TINY_SRCU
> -int __srcu_read_lock_lite(struct srcu_struct *ssp) __acquires(ssp);
> -void __srcu_read_unlock_lite(struct srcu_struct *ssp, int idx) __releases(ssp);
> -#endif // #else // #ifdef CONFIG_TINY_SRCU
>  void synchronize_srcu(struct srcu_struct *ssp);
>  
>  #define SRCU_GET_STATE_COMPLETED 0x1
> diff --git a/include/linux/srcutree.h b/include/linux/srcutree.h
> index 490aeecc6bb4..16a7d631c185 100644
> --- a/include/linux/srcutree.h
> +++ b/include/linux/srcutree.h
> @@ -219,7 +219,7 @@ void srcu_torture_stats_print(struct srcu_struct *ssp, char *tt, char *tf);
>   * or because it is a read-modify-write atomic operation, depending on
>   * the whims of the architecture.
>   */
> -static inline int __srcu_read_lock_lite(struct srcu_struct *ssp)
> +static inline int __srcu_read_lock_lite(struct srcu_struct *ssp) __acquires(ssp)
>  {
>  	int idx;
>  
> @@ -241,7 +241,7 @@ static inline int __srcu_read_lock_lite(struct srcu_struct *ssp)
>   * or because it is a read-modify-write atomic operation, depending on
>   * the whims of the architecture.
>   */
> -static inline void __srcu_read_unlock_lite(struct srcu_struct *ssp, int idx)
> +static inline void __srcu_read_unlock_lite(struct srcu_struct *ssp, int idx) __releases(ssp)
>  {
>  	barrier();  /* Avoid leaking the critical section. */
>  	this_cpu_inc(ssp->sda->srcu_unlock_count[idx].counter);  /* Z */
> -- 
> 2.43.0
>