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NAME ck_epoch_barrier -- block until a grace period and all callbacks have been dispatched LIBRARY Concurrency Kit (libck, -lck) SYNOPSIS #include <ck_epoch.h> void ck_epoch_barrier(ck_epoch_record_t *record); DESCRIPTION The ck_epoch_barrier(3) function will block the caller until a grace period has been detected, according to the semantics of epoch reclamation. Any objects requiring safe memory reclamation which are logically deleted are safe for physical deletion following a call to ck_epoch_barrier(3). This function will also dispatch all callbacks associated with epoch that were previously scheduled via ck_epoch_call(3). EXAMPLE #include <ck_epoch.h> #include <ck_stack.h> #include <stdlib.h> /* * epoch was previously initialized with ck_epoch_init. * stack was previously initialized with ck_stack_init. */ ck_epoch_t *epoch; ck_stack_t *stack; void function(void) { ck_epoch_record_t *record; ck_stack_entry_t *s; record = malloc(sizeof *record); ck_epoch_register(&epoch, record, NULL); /* * We are using an epoch section here to guarantee no * nodes in the stack are deleted while we are dereferencing * them. This is needed here because there are multiple writers. * If there was only one thread popping from the this stack, * then there is no need to ck_epoch_begin/ck_epoch_end. */ ck_epoch_begin(record); /* Logically delete an object. */ s = ck_stack_pop_upmc(stack); ck_epoch_end(record); /* * Wait until no threads could possibly have a reference to the * object we just popped (assume all threads are simply executing * ck_stack_pop_upmc). */ ck_epoch_barrier(record); /* It is now safe to physically delete the object. */ free(s); return; } RETURN VALUES This function has no return value. ERRORS Behavior is undefined if the object pointed to by epoch is not a valid epoch object. The object pointed to by record must have been previously registered via ck_epoch_register(3). SEE ALSO ck_epoch_init(3), ck_epoch_register(3), ck_epoch_unregister(3), ck_epoch_recycle(3), ck_epoch_poll(3), ck_epoch_synchronize(3), ck_epoch_reclaim(3), ck_epoch_call(3), ck_epoch_begin(3), ck_epoch_end(3) Additional information available at http://concurrencykit.org/ September 2, 2012 CK_EPOCH_BARRIER(3)
NAME | LIBRARY | SYNOPSIS | DESCRIPTION | EXAMPLE | RETURN VALUES | ERRORS | SEE ALSO
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