From f9411ebe3d85cbbea06298241e6053d031d281fc Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 6 Feb 2017 09:50:49 +0100 Subject: [PATCH] rcu: Separate the RCU synchronization types and APIs into So rcupdate.h is a pretty complex header, in particular it includes which includes - creating a dependency that includes in , which prevents the isolation of from the derived header. Solve part of the problem by decoupling rcupdate.h from completions: this can be done by separating out the rcu_synchronize types and APIs, and updating their usage sites. Since this is a mostly RCU-internal types this will not just simplify 's dependencies, but will make all the hundreds of .c files that include rcupdate.h but not completions or wait.h build faster. ( For rcutiny this means that two dependent APIs have to be uninlined, but that shouldn't be much of a problem as they are rare variants. ) Acked-by: Linus Torvalds Cc: Mike Galbraith Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- fs/autofs4/autofs_i.h | 1 + include/linux/dcache.h | 1 + include/linux/rcupdate.h | 40 ---------------------------- include/linux/rcupdate_wait.h | 50 +++++++++++++++++++++++++++++++++++ include/linux/rcutiny.h | 11 ++------ kernel/rcu/srcu.c | 2 +- kernel/rcu/tiny.c | 14 +++++++++- kernel/rcu/tree.c | 2 +- kernel/rcu/update.c | 1 + kernel/sched/core.c | 1 + 10 files changed, 71 insertions(+), 52 deletions(-) create mode 100644 include/linux/rcupdate_wait.h diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h index c885daae68c8..beef981aa54f 100644 --- a/fs/autofs4/autofs_i.h +++ b/fs/autofs4/autofs_i.h @@ -14,6 +14,7 @@ #include #include #include +#include /* This is the range of ioctl() numbers we claim as ours */ #define AUTOFS_IOC_FIRST AUTOFS_IOC_READY diff --git a/include/linux/dcache.h b/include/linux/dcache.h index 591b6c16f9c1..d2e38dc6172c 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -11,6 +11,7 @@ #include #include #include +#include struct path; struct vfsmount; diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 6ade6a52d9d4..de88b33c0974 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -40,7 +40,6 @@ #include #include #include -#include #include #include #include @@ -226,45 +225,6 @@ void call_rcu_sched(struct rcu_head *head, void synchronize_sched(void); -/* - * Structure allowing asynchronous waiting on RCU. - */ -struct rcu_synchronize { - struct rcu_head head; - struct completion completion; -}; -void wakeme_after_rcu(struct rcu_head *head); - -void __wait_rcu_gp(bool checktiny, int n, call_rcu_func_t *crcu_array, - struct rcu_synchronize *rs_array); - -#define _wait_rcu_gp(checktiny, ...) \ -do { \ - call_rcu_func_t __crcu_array[] = { __VA_ARGS__ }; \ - struct rcu_synchronize __rs_array[ARRAY_SIZE(__crcu_array)]; \ - __wait_rcu_gp(checktiny, ARRAY_SIZE(__crcu_array), \ - __crcu_array, __rs_array); \ -} while (0) - -#define wait_rcu_gp(...) _wait_rcu_gp(false, __VA_ARGS__) - -/** - * synchronize_rcu_mult - Wait concurrently for multiple grace periods - * @...: List of call_rcu() functions for the flavors to wait on. - * - * This macro waits concurrently for multiple flavors of RCU grace periods. - * For example, synchronize_rcu_mult(call_rcu, call_rcu_bh) would wait - * on concurrent RCU and RCU-bh grace periods. Waiting on a give SRCU - * domain requires you to write a wrapper function for that SRCU domain's - * call_srcu() function, supplying the corresponding srcu_struct. - * - * If Tiny RCU, tell _wait_rcu_gp() not to bother waiting for RCU - * or RCU-bh, given that anywhere synchronize_rcu_mult() can be called - * is automatically a grace period. - */ -#define synchronize_rcu_mult(...) \ - _wait_rcu_gp(IS_ENABLED(CONFIG_TINY_RCU), __VA_ARGS__) - /** * call_rcu_tasks() - Queue an RCU for invocation task-based grace period * @head: structure to be used for queueing the RCU updates. diff --git a/include/linux/rcupdate_wait.h b/include/linux/rcupdate_wait.h new file mode 100644 index 000000000000..e774b4f5f220 --- /dev/null +++ b/include/linux/rcupdate_wait.h @@ -0,0 +1,50 @@ +#ifndef _LINUX_SCHED_RCUPDATE_WAIT_H +#define _LINUX_SCHED_RCUPDATE_WAIT_H + +/* + * RCU synchronization types and methods: + */ + +#include +#include + +/* + * Structure allowing asynchronous waiting on RCU. + */ +struct rcu_synchronize { + struct rcu_head head; + struct completion completion; +}; +void wakeme_after_rcu(struct rcu_head *head); + +void __wait_rcu_gp(bool checktiny, int n, call_rcu_func_t *crcu_array, + struct rcu_synchronize *rs_array); + +#define _wait_rcu_gp(checktiny, ...) \ +do { \ + call_rcu_func_t __crcu_array[] = { __VA_ARGS__ }; \ + struct rcu_synchronize __rs_array[ARRAY_SIZE(__crcu_array)]; \ + __wait_rcu_gp(checktiny, ARRAY_SIZE(__crcu_array), \ + __crcu_array, __rs_array); \ +} while (0) + +#define wait_rcu_gp(...) _wait_rcu_gp(false, __VA_ARGS__) + +/** + * synchronize_rcu_mult - Wait concurrently for multiple grace periods + * @...: List of call_rcu() functions for the flavors to wait on. + * + * This macro waits concurrently for multiple flavors of RCU grace periods. + * For example, synchronize_rcu_mult(call_rcu, call_rcu_bh) would wait + * on concurrent RCU and RCU-bh grace periods. Waiting on a give SRCU + * domain requires you to write a wrapper function for that SRCU domain's + * call_srcu() function, supplying the corresponding srcu_struct. + * + * If Tiny RCU, tell _wait_rcu_gp() not to bother waiting for RCU + * or RCU-bh, given that anywhere synchronize_rcu_mult() can be called + * is automatically a grace period. + */ +#define synchronize_rcu_mult(...) \ + _wait_rcu_gp(IS_ENABLED(CONFIG_TINY_RCU), __VA_ARGS__) + +#endif /* _LINUX_SCHED_RCUPDATE_WAIT_H */ diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h index 4f9b2fa2173d..b452953e21c8 100644 --- a/include/linux/rcutiny.h +++ b/include/linux/rcutiny.h @@ -53,15 +53,8 @@ static inline void cond_synchronize_sched(unsigned long oldstate) might_sleep(); } -static inline void rcu_barrier_bh(void) -{ - wait_rcu_gp(call_rcu_bh); -} - -static inline void rcu_barrier_sched(void) -{ - wait_rcu_gp(call_rcu_sched); -} +extern void rcu_barrier_bh(void); +extern void rcu_barrier_sched(void); static inline void synchronize_rcu_expedited(void) { diff --git a/kernel/rcu/srcu.c b/kernel/rcu/srcu.c index e773129c8b08..ef3bcfb15b39 100644 --- a/kernel/rcu/srcu.c +++ b/kernel/rcu/srcu.c @@ -30,7 +30,7 @@ #include #include #include -#include +#include #include #include #include diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c index fa6a48d3917b..6ad330dbbae2 100644 --- a/kernel/rcu/tiny.c +++ b/kernel/rcu/tiny.c @@ -25,7 +25,7 @@ #include #include #include -#include +#include #include #include #include @@ -47,6 +47,18 @@ static void __call_rcu(struct rcu_head *head, #include "tiny_plugin.h" +void rcu_barrier_bh(void) +{ + wait_rcu_gp(call_rcu_bh); +} +EXPORT_SYMBOL(rcu_barrier_bh); + +void rcu_barrier_sched(void) +{ + wait_rcu_gp(call_rcu_sched); +} +EXPORT_SYMBOL(rcu_barrier_sched); + #if defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_RCU_TRACE) /* diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index d80e0d2f68c6..cb62ce23ffc7 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -32,7 +32,7 @@ #include #include #include -#include +#include #include #include #include diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index 9e03db9ea9c0..a0e90e0afc75 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -49,6 +49,7 @@ #include #include #include +#include #define CREATE_TRACE_POINTS diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 2d51ec65dc73..1bd317db9810 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include -- 2.30.2