From: Oleg Nesterov Add the new struct rcu_sync_ops which holds sync/call methods, and turn the function pointers in rcu_sync_struct into an array of struct rcu_sync_ops. This simplifies the "init" helpers, and this way it is simpler to add the new methods we need, especially ifdef'ed. Reviewed-by: Paul E. McKenney Signed-off-by: Oleg Nesterov Signed-off-by: Peter Zijlstra (Intel) --- include/linux/rcusync.h | 60 ++++++++++++++++++------------------------------ kernel/rcu/sync.c | 43 +++++++++++++++++----------------- 2 files changed, 45 insertions(+), 58 deletions(-) --- a/include/linux/rcusync.h +++ b/include/linux/rcusync.h @@ -4,6 +4,8 @@ #include #include +enum rcu_sync_type { RCU_SYNC, RCU_SCHED_SYNC, RCU_BH_SYNC }; + struct rcu_sync_struct { int gp_state; int gp_count; @@ -12,53 +14,37 @@ struct rcu_sync_struct { int cb_state; struct rcu_head cb_head; - void (*sync)(void); - void (*call)(struct rcu_head *, void (*)(struct rcu_head *)); + enum rcu_sync_type gp_type; }; -#define ___RCU_SYNC_INIT(name) \ - .gp_state = 0, \ - .gp_count = 0, \ - .gp_wait = __WAIT_QUEUE_HEAD_INITIALIZER(name.gp_wait), \ - .cb_state = 0 - -#define __RCU_SCHED_SYNC_INIT(name) { \ - ___RCU_SYNC_INIT(name), \ - .sync = synchronize_sched, \ - .call = call_rcu_sched, \ -} - -#define __RCU_BH_SYNC_INIT(name) { \ - ___RCU_SYNC_INIT(name), \ - .sync = synchronize_rcu_bh, \ - .call = call_rcu_bh, \ -} - -#define __RCU_SYNC_INIT(name) { \ - ___RCU_SYNC_INIT(name), \ - .sync = synchronize_rcu, \ - .call = call_rcu, \ -} - -#define DEFINE_RCU_SCHED_SYNC(name) \ - struct rcu_sync_struct name = __RCU_SCHED_SYNC_INIT(name) - -#define DEFINE_RCU_BH_SYNC(name) \ - struct rcu_sync_struct name = __RCU_BH_SYNC_INIT(name) - -#define DEFINE_RCU_SYNC(name) \ - struct rcu_sync_struct name = __RCU_SYNC_INIT(name) - static inline bool rcu_sync_is_idle(struct rcu_sync_struct *rss) { return !rss->gp_state; /* GP_IDLE */ } -enum rcu_sync_type { RCU_SYNC, RCU_SCHED_SYNC, RCU_BH_SYNC }; - extern void rcu_sync_init(struct rcu_sync_struct *, enum rcu_sync_type); extern void rcu_sync_enter(struct rcu_sync_struct *); extern void rcu_sync_exit(struct rcu_sync_struct *); +#define __RCU_SYNC_INITIALIZER(name, type) { \ + .gp_state = 0, \ + .gp_count = 0, \ + .gp_wait = __WAIT_QUEUE_HEAD_INITIALIZER(name.gp_wait), \ + .cb_state = 0, \ + .gp_type = type, \ + } + +#define __DEFINE_RCU_SYNC(name, type) \ + struct rcu_sync_struct name = __RCU_SYNC_INITIALIZER(name, type) + +#define DEFINE_RCU_SYNC(name) \ + __DEFINE_RCU_SYNC(name, RCU_SYNC) + +#define DEFINE_RCU_SCHED_SYNC(name) \ + __DEFINE_RCU_SYNC(name, RCU_SCHED_SYNC) + +#define DEFINE_RCU_BH_SYNC(name) \ + __DEFINE_RCU_SYNC(name, RCU_BH_SYNC) + #endif /* _LINUX_RCUSYNC_H_ */ --- a/kernel/rcu/sync.c +++ b/kernel/rcu/sync.c @@ -1,7 +1,24 @@ - #include #include +static const struct { + void (*sync)(void); + void (*call)(struct rcu_head *, void (*)(struct rcu_head *)); +} gp_ops[] = { + [RCU_SYNC] = { + .sync = synchronize_rcu, + .call = call_rcu, + }, + [RCU_SCHED_SYNC] = { + .sync = synchronize_sched, + .call = call_rcu_sched, + }, + [RCU_BH_SYNC] = { + .sync = synchronize_rcu_bh, + .call = call_rcu_bh, + }, +}; + enum { GP_IDLE = 0, GP_PENDING, GP_PASSED }; enum { CB_IDLE = 0, CB_PENDING, CB_REPLAY }; @@ -11,23 +28,7 @@ void rcu_sync_init(struct rcu_sync_struc { memset(rss, 0, sizeof(*rss)); init_waitqueue_head(&rss->gp_wait); - - switch (type) { - case RCU_SYNC: - rss->sync = synchronize_rcu; - rss->call = call_rcu; - break; - - case RCU_SCHED_SYNC: - rss->sync = synchronize_sched; - rss->call = call_rcu_sched; - break; - - case RCU_BH_SYNC: - rss->sync = synchronize_rcu_bh; - rss->call = call_rcu_bh; - break; - } + rss->gp_type = type; } void rcu_sync_enter(struct rcu_sync_struct *rss) @@ -44,7 +45,7 @@ void rcu_sync_enter(struct rcu_sync_stru BUG_ON(need_wait && need_sync); if (need_sync) { - rss->sync(); + gp_ops[rss->gp_type].sync(); rss->gp_state = GP_PASSED; wake_up_all(&rss->gp_wait); } else if (need_wait) { @@ -81,7 +82,7 @@ static void rcu_sync_func(struct rcu_hea * to catch a later GP. */ rss->cb_state = CB_PENDING; - rss->call(&rss->cb_head, rcu_sync_func); + gp_ops[rss->gp_type].call(&rss->cb_head, rcu_sync_func); } else { /* * We're at least a GP after rcu_sync_exit(); eveybody will now @@ -99,7 +100,7 @@ void rcu_sync_exit(struct rcu_sync_struc if (!--rss->gp_count) { if (rss->cb_state == CB_IDLE) { rss->cb_state = CB_PENDING; - rss->call(&rss->cb_head, rcu_sync_func); + gp_ops[rss->gp_type].call(&rss->cb_head, rcu_sync_func); } else if (rss->cb_state == CB_PENDING) { rss->cb_state = CB_REPLAY; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/