X-Git-Url: https://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=urcu-static.h;h=b465ce40a3f020dcfbbfb4226c53356a6c56b953;hp=5a75dde18630a84908f82b3096cb166a875b8ae6;hb=27d65bc5db18f8563a9120924569acffb845ec4d;hpb=ddf7eefbdd2ff77c473534dfa89c3fe12c206d67 diff --git a/urcu-static.h b/urcu-static.h index 5a75dde..b465ce4 100644 --- a/urcu-static.h +++ b/urcu-static.h @@ -160,10 +160,25 @@ static inline void debug_yield_init(void) } #endif +/* + * RCU memory barrier broadcast group. Currently, only broadcast to all process + * threads is supported (group 0). + * + * Slave barriers are only guaranteed to be ordered wrt master barriers. + * + * The pair ordering is detailed as (O: ordered, X: not ordered) : + * slave master + * slave X O + * master O O + */ + +#define MB_GROUP_ALL 0 +#define RCU_MB_GROUP MB_GROUP_ALL + #ifdef RCU_MEMBARRIER extern int has_sys_membarrier; -static inline void smp_mb_light() +static inline void smp_mb_slave(int group) { if (likely(has_sys_membarrier)) barrier(); @@ -173,14 +188,14 @@ static inline void smp_mb_light() #endif #ifdef RCU_MB -static inline void smp_mb_light() +static inline void smp_mb_slave(int group) { smp_mb(); } #endif #ifdef RCU_SIGNAL -static inline void smp_mb_light() +static inline void smp_mb_slave(int group) { barrier(); } @@ -192,7 +207,7 @@ static inline void smp_mb_light() */ #define RCU_GP_COUNT (1UL << 0) /* Use the amount of bits equal to half of the architecture long size */ -#define RCU_GP_CTR_PHASE (1UL << (sizeof(long) << 2)) +#define RCU_GP_CTR_PHASE (1UL << (sizeof(unsigned long) << 2)) #define RCU_GP_CTR_NEST_MASK (RCU_GP_CTR_PHASE - 1) /* @@ -200,11 +215,11 @@ static inline void smp_mb_light() * Using a int rather than a char to eliminate false register dependencies * causing stalls on some architectures. */ -extern long rcu_gp_ctr; +extern unsigned long rcu_gp_ctr; struct rcu_reader { /* Data used by both reader and synchronize_rcu() */ - long ctr; + unsigned long ctr; char need_mb; /* Data used for registry */ struct list_head head __attribute__((aligned(CACHE_LINE_SIZE))); @@ -227,9 +242,9 @@ static inline void wake_up_gp(void) } } -static inline int rcu_old_gp_ongoing(long *value) +static inline int rcu_old_gp_ongoing(unsigned long *value) { - long v; + unsigned long v; if (value == NULL) return 0; @@ -244,7 +259,7 @@ static inline int rcu_old_gp_ongoing(long *value) static inline void _rcu_read_lock(void) { - long tmp; + unsigned long tmp; tmp = rcu_reader.ctr; /* @@ -255,9 +270,9 @@ static inline void _rcu_read_lock(void) _STORE_SHARED(rcu_reader.ctr, _LOAD_SHARED(rcu_gp_ctr)); /* * Set active readers count for outermost nesting level before - * accessing the pointer. See smp_mb_heavy(). + * accessing the pointer. See smp_mb_master(). */ - smp_mb_light(); + smp_mb_slave(RCU_MB_GROUP); } else { _STORE_SHARED(rcu_reader.ctr, tmp + RCU_GP_COUNT); } @@ -265,18 +280,18 @@ static inline void _rcu_read_lock(void) static inline void _rcu_read_unlock(void) { - long tmp; + unsigned long tmp; tmp = rcu_reader.ctr; /* * Finish using rcu before decrementing the pointer. - * See smp_mb_heavy(). + * See smp_mb_master(). */ if (likely((tmp & RCU_GP_CTR_NEST_MASK) == RCU_GP_COUNT)) { - smp_mb_light(); + smp_mb_slave(RCU_MB_GROUP); _STORE_SHARED(rcu_reader.ctr, rcu_reader.ctr - RCU_GP_COUNT); /* write rcu_reader.ctr before read futex */ - smp_mb_light(); + smp_mb_slave(RCU_MB_GROUP); wake_up_gp(); } else { _STORE_SHARED(rcu_reader.ctr, rcu_reader.ctr - RCU_GP_COUNT);