X-Git-Url: https://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=urcu-static.h;h=f68dd7c8dc1231641d040d6aeebad2a5da56970f;hp=44bcd073710e3e98d760c667eb7aa787238bb3ff;hb=5db941e8f87f9728883c2dd0446698d13d5b9fec;hpb=f0708810fe66d7fdcf52903c607ed65c9fa664c7 diff --git a/urcu-static.h b/urcu-static.h index 44bcd07..f68dd7c 100644 --- a/urcu-static.h +++ b/urcu-static.h @@ -56,9 +56,10 @@ extern "C" { /* If the headers do not support SYS_membarrier, statically use RCU_MB */ #ifdef SYS_membarrier -# define MEMBARRIER_EXPEDITED (1 << 0) -# define MEMBARRIER_DELAYED (1 << 1) -# define membarrier(...) syscall(__NR_membarrier, __VA_ARGS__) +# define MEMBARRIER_EXPEDITED (1 << 0) +# define MEMBARRIER_DELAYED (1 << 1) +# define MEMBARRIER_QUERY (1 << 16) +# define membarrier(...) syscall(SYS_membarrier, __VA_ARGS__) #else # undef RCU_MEMBARRIER # define RCU_MB @@ -76,7 +77,12 @@ extern "C" { /* * The signal number used by the RCU library can be overridden with * -DSIGRCU= when compiling the library. + * Provide backward compatibility for liburcu 0.3.x SIGURCU. */ +#ifdef SIGURCU +#define SIGRCU SIGURCU +#endif + #ifndef SIGRCU #define SIGRCU SIGUSR1 #endif @@ -154,10 +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(); @@ -167,14 +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(); } @@ -186,7 +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) /* @@ -194,11 +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))); @@ -221,24 +242,22 @@ static inline void wake_up_gp(void) } } -static inline int rcu_old_gp_ongoing(long *value) +static inline int rcu_gp_ongoing(unsigned long *ctr) { - long v; + unsigned long v; - if (value == NULL) - return 0; /* * Make sure both tests below are done on the same version of *value * to insure consistency. */ - v = LOAD_SHARED(*value); + v = LOAD_SHARED(*ctr); return (v & RCU_GP_CTR_NEST_MASK) && ((v ^ rcu_gp_ctr) & RCU_GP_CTR_PHASE); } static inline void _rcu_read_lock(void) { - long tmp; + unsigned long tmp; tmp = rcu_reader.ctr; /* @@ -249,9 +268,9 @@ 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); } @@ -259,18 +278,18 @@ 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);