Re: [PATCH 50/50] Kill sched.h dependency on rcupdate.h

From: Paul E. McKenney
Date: Sat Dec 16 2023 - 14:35:18 EST


On Fri, Dec 15, 2023 at 10:35:51PM -0500, Kent Overstreet wrote:
> by moving cond_resched_rcu() to rcupdate.h, we can kill another big
> sched.h dependency.
>
> Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>

Could you please instead move the cond_resched_rcu() function to
include/linux/rcupdate_wait.h? This would avoid breaking Ingo's
separation that makes it possible to include rcupdate.h without also
pulling in sched.h.

Thanx, Paul

> ---
> include/linux/rcupdate.h | 11 +++++++++++
> include/linux/sched.h | 13 +++----------
> 2 files changed, 14 insertions(+), 10 deletions(-)
>
> diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
> index f7206b2623c9..8ebfa57e0164 100644
> --- a/include/linux/rcupdate.h
> +++ b/include/linux/rcupdate.h
> @@ -1058,4 +1058,15 @@ extern int rcu_normal;
>
> DEFINE_LOCK_GUARD_0(rcu, rcu_read_lock(), rcu_read_unlock())
>
> +#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
> +#define cond_resched_rcu() \
> +do { \
> + rcu_read_unlock(); \
> + cond_resched(); \
> + rcu_read_lock(); \
> +} while (0)
> +#else
> +#define cond_resched_rcu()
> +#endif
> +
> #endif /* __LINUX_RCUPDATE_H */
> diff --git a/include/linux/sched.h b/include/linux/sched.h
> index d528057c99e4..b781ac7e0a02 100644
> --- a/include/linux/sched.h
> +++ b/include/linux/sched.h
> @@ -10,8 +10,11 @@
> #include <uapi/linux/sched.h>
>
> #include <asm/current.h>
> +#include <linux/thread_info.h>
> +#include <linux/preempt.h>
>
> #include <linux/irqflags_types.h>
> +#include <linux/smp_types.h>
> #include <linux/pid_types.h>
> #include <linux/sem_types.h>
> #include <linux/shm.h>
> @@ -22,7 +25,6 @@
> #include <linux/timer_types.h>
> #include <linux/seccomp_types.h>
> #include <linux/nodemask_types.h>
> -#include <linux/rcupdate.h>
> #include <linux/refcount_types.h>
> #include <linux/resource.h>
> #include <linux/latencytop.h>
> @@ -2058,15 +2060,6 @@ extern int __cond_resched_rwlock_write(rwlock_t *lock);
> __cond_resched_rwlock_write(lock); \
> })
>
> -static inline void cond_resched_rcu(void)
> -{
> -#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
> - rcu_read_unlock();
> - cond_resched();
> - rcu_read_lock();
> -#endif
> -}
> -
> #ifdef CONFIG_PREEMPT_DYNAMIC
>
> extern bool preempt_model_none(void);
> --
> 2.43.0
>