#include <unistd.h>
#include <sys/mman.h>
-#include "urcu/wfqueue.h"
+#include "urcu/wfcqueue.h"
#include "urcu/map/urcu-bp.h"
#include "urcu/static/urcu-bp.h"
#include "urcu-pointer.h"
+#include "urcu/tls-compat.h"
+
+#include "urcu-die.h"
/* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */
#undef _LGPL_SOURCE
#define MAP_ANONYMOUS MAP_ANON
#endif
-#ifndef __linux__
+#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.
*/
-void *mremap(void *old_address, size_t old_size, size_t new_size, int flags)
+static
+void *mremap_wrapper(void *old_address, size_t old_size,
+ size_t new_size, int flags)
{
void *new_address;
static pthread_mutex_t rcu_gp_lock = PTHREAD_MUTEX_INITIALIZER;
#ifdef DEBUG_YIELD
-unsigned int yield_active;
-unsigned int __thread rand_yield;
+unsigned int rcu_yield_active;
+DEFINE_URCU_TLS(unsigned int, rcu_rand_yield);
#endif
/*
* 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);
#ifndef DISTRUST_SIGNALS_EXTREME
ret = pthread_mutex_lock(mutex);
- if (ret) {
- perror("Error in pthread mutex lock");
- exit(-1);
- }
+ if (ret)
+ urcu_die(ret);
#else /* #ifndef DISTRUST_SIGNALS_EXTREME */
while ((ret = pthread_mutex_trylock(mutex)) != 0) {
- if (ret != EBUSY && ret != EINTR) {
- printf("ret = %d, errno = %d\n", ret, errno);
- perror("Error in pthread mutex lock");
- exit(-1);
- }
+ if (ret != EBUSY && ret != EINTR)
+ urcu_die(ret);
poll(NULL,0,10);
}
#endif /* #else #ifndef DISTRUST_SIGNALS_EXTREME */
int ret;
ret = pthread_mutex_unlock(mutex);
- if (ret) {
- perror("Error in pthread mutex unlock");
- exit(-1);
- }
+ if (ret)
+ urcu_die(ret);
}
-void update_counter_and_wait(void)
+static void wait_for_readers(void)
{
CDS_LIST_HEAD(qsreaders);
int wait_loops = 0;
struct rcu_reader *index, *tmp;
- /* Switch parity: 0 -> 1, 1 -> 0 */
- CMM_STORE_SHARED(rcu_gp_ctr, rcu_gp_ctr ^ RCU_GP_CTR_PHASE);
-
- /*
- * Must commit qparity update to memory before waiting for other parity
- * quiescent state. Failure to do so could result in the writer waiting
- * forever while new readers are always accessing data (no progress).
- * Ensured by CMM_STORE_SHARED and CMM_LOAD_SHARED.
- */
-
- /*
- * Adding a cmm_smp_mb() which is _not_ formally required, but makes the
- * model easier to understand. It does not have a big performance impact
- * anyway, given this is the write-side.
- */
- cmm_smp_mb();
-
/*
- * Wait for each thread rcu_reader.ctr count to become 0.
+ * Wait for each thread URCU_TLS(rcu_reader).ctr to either
+ * indicate quiescence (not nested), or observe the current
+ * rcu_gp_ctr value.
*/
for (;;) {
wait_loops++;
rcu_gc_registry();
/*
- * Wait for previous parity to be empty of readers.
+ * Wait for readers to observe original parity or be quiescent.
+ */
+ wait_for_readers();
+
+ /*
+ * Adding a cmm_smp_mb() which is _not_ formally required, but makes the
+ * model easier to understand. It does not have a big performance impact
+ * anyway, given this is the write-side.
+ */
+ cmm_smp_mb();
+
+ /* Switch parity: 0 -> 1, 1 -> 0 */
+ CMM_STORE_SHARED(rcu_gp_ctr, rcu_gp_ctr ^ RCU_GP_CTR_PHASE);
+
+ /*
+ * Must commit qparity update to memory before waiting for other parity
+ * quiescent state. Failure to do so could result in the writer waiting
+ * forever while new readers are always accessing data (no progress).
+ * Ensured by CMM_STORE_SHARED and CMM_LOAD_SHARED.
*/
- update_counter_and_wait(); /* 0 -> 1, wait readers in parity 0 */
/*
* Adding a cmm_smp_mb() which is _not_ formally required, but makes the
cmm_smp_mb();
/*
- * Wait for previous parity to be empty of readers.
+ * Wait for readers to observe new parity or be quiescent.
*/
- update_counter_and_wait(); /* 1 -> 0, wait readers in parity 1 */
+ wait_for_readers();
/*
* Finish waiting for reader threads before letting the old ptr being
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);
/*
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 */
/*
* 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);
void *rcu_set_pointer_sym_bp(void **p, void *v)
{
cmm_wmb();
- return uatomic_set(p, v);
+ uatomic_set(p, v);
+ return v;
}
void *rcu_xchg_pointer_sym_bp(void **p, void *v)
return uatomic_cmpxchg(p, old, _new);
}
-DEFINE_RCU_FLAVOR()
+DEFINE_RCU_FLAVOR(rcu_flavor);
#include "urcu-call-rcu-impl.h"
#include "urcu-defer-impl.h"