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

From: Paul E. McKenney
Date: Thu Jan 16 2025 - 11:03:50 EST


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@xxxxxxxxxx>

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
>