X-Git-Url: http://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=urcu-bp.c;h=67eae07b6e1b3f69c9cc4739d524dd45de899daf;hp=915debe2c5c2f89da1f1d096f9d5712a5283f28a;hb=3e056c21610d5c0c5591fcb0bc714dfe26bff3a3;hpb=57760d447eaed07f8a9c6552b8cefc6223ac1158 diff --git a/urcu-bp.c b/urcu-bp.c index 915debe..67eae07 100644 --- a/urcu-bp.c +++ b/urcu-bp.c @@ -24,6 +24,7 @@ */ #define _GNU_SOURCE +#define _LGPL_SOURCE #include #include #include @@ -35,23 +36,75 @@ #include #include +#include "urcu/wfqueue.h" #include "urcu/map/urcu-bp.h" +#include "urcu/static/urcu-bp.h" +#include "urcu-pointer.h" +#include "urcu/tls-compat.h" -#include "urcu-bp-static.h" /* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */ +#undef _LGPL_SOURCE #include "urcu-bp.h" +#define _LGPL_SOURCE + +#ifndef MAP_ANONYMOUS +#define MAP_ANONYMOUS MAP_ANON +#endif + +#ifdef __linux__ +static +void *mremap_wrapper(void *old_address, size_t old_size, + size_t new_size, int flags) +{ + return mremap(old_address, old_size, new_size, flags); +} +#else + +#define MREMAP_MAYMOVE 1 +#define MREMAP_FIXED 2 + +/* + * mremap wrapper for non-Linux systems. Maps a RW, anonymous private mapping. + * This is not generic. +*/ +static +void *mremap_wrapper(void *old_address, size_t old_size, + size_t new_size, int flags) +{ + void *new_address; + + assert(flags & MREMAP_MAYMOVE); + assert(!(flags & MREMAP_FIXED)); + new_address = mmap(old_address, new_size, + PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_PRIVATE, + -1, 0); + if (new_address == MAP_FAILED) + return MAP_FAILED; + if (old_address) { + memcpy(new_address, old_address, old_size); + munmap(old_address, old_size); + } + return new_address; +} +#endif /* Sleep delay in us */ #define RCU_SLEEP_DELAY 1000 #define ARENA_INIT_ALLOC 16 +/* + * Active attempts to check for reader Q.S. before calling sleep(). + */ +#define RCU_QS_ACTIVE_ATTEMPTS 100 + void __attribute__((destructor)) rcu_bp_exit(void); static pthread_mutex_t rcu_gp_lock = PTHREAD_MUTEX_INITIALIZER; #ifdef DEBUG_YIELD unsigned int yield_active; -unsigned int __thread rand_yield; +DEFINE_URCU_TLS(unsigned int, rand_yield); #endif /* @@ -66,7 +119,7 @@ long rcu_gp_ctr = RCU_GP_COUNT; * Pointer to registry elements. Written to only by each individual reader. Read * by both the reader and the writers. */ -struct rcu_reader __thread *rcu_reader; +DEFINE_URCU_TLS(struct rcu_reader *, rcu_reader); static CDS_LIST_HEAD(registry); @@ -240,8 +293,8 @@ static void resize_arena(struct registry_arena *arena, size_t len) MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); else - new_arena = mremap(arena->p, arena->len, - len, MREMAP_MAYMOVE); + new_arena = mremap_wrapper(arena->p, arena->len, + len, MREMAP_MAYMOVE); assert(new_arena != MAP_FAILED); /* @@ -250,7 +303,6 @@ static void resize_arena(struct registry_arena *arena, size_t len) if (new_arena == arena->p) return; - memcpy(new_arena, arena->p, arena->len); bzero(new_arena + arena->len, len - arena->len); arena->p = new_arena; } @@ -263,7 +315,7 @@ static void add_thread(void) if (registry_arena.len < registry_arena.used + sizeof(struct rcu_reader)) resize_arena(®istry_arena, - max(registry_arena.len << 1, ARENA_INIT_ALLOC)); + caa_max(registry_arena.len << 1, ARENA_INIT_ALLOC)); /* * Find a free spot. */ @@ -280,7 +332,7 @@ static void add_thread(void) rcu_reader_reg->tid = pthread_self(); assert(rcu_reader_reg->ctr == 0); cds_list_add(&rcu_reader_reg->node, ®istry); - rcu_reader = rcu_reader_reg; + URCU_TLS(rcu_reader) = rcu_reader_reg; } /* Called with signals off and mutex locked */ @@ -321,7 +373,7 @@ void rcu_bp_register(void) /* * Check if a signal concurrently registered our thread since * the check in rcu_read_lock(). */ - if (rcu_reader) + if (URCU_TLS(rcu_reader)) goto end; mutex_lock(&rcu_gp_lock); @@ -332,9 +384,10 @@ end: assert(!ret); } -void rcu_bp_exit() +void rcu_bp_exit(void) { - munmap(registry_arena.p, registry_arena.len); + if (registry_arena.p) + munmap(registry_arena.p, registry_arena.len); } /* @@ -378,5 +431,31 @@ void rcu_bp_after_fork_child(void) assert(!ret); } +void *rcu_dereference_sym_bp(void *p) +{ + return _rcu_dereference(p); +} + +void *rcu_set_pointer_sym_bp(void **p, void *v) +{ + cmm_wmb(); + uatomic_set(p, v); + return v; +} + +void *rcu_xchg_pointer_sym_bp(void **p, void *v) +{ + cmm_wmb(); + return uatomic_xchg(p, v); +} + +void *rcu_cmpxchg_pointer_sym_bp(void **p, void *old, void *_new) +{ + cmm_wmb(); + return uatomic_cmpxchg(p, old, _new); +} + +DEFINE_RCU_FLAVOR(rcu_flavor); + #include "urcu-call-rcu-impl.h" #include "urcu-defer-impl.h"