diff --git a/src/core/support/stack_lockfree.c b/src/core/support/stack_lockfree.c index 83a68444f5f2cf8f46906071591585e55544cc5a..598aa9cdf18364b9e3bf1fe98495ab149fa79973 100644 --- a/src/core/support/stack_lockfree.c +++ b/src/core/support/stack_lockfree.c @@ -95,7 +95,7 @@ void gpr_stack_lockfree_destroy(gpr_stack_lockfree *stack) { gpr_free(stack); } -void gpr_stack_lockfree_push(gpr_stack_lockfree *stack, int entry) { +int gpr_stack_lockfree_push(gpr_stack_lockfree *stack, int entry) { lockfree_node head; lockfree_node newhead; @@ -112,6 +112,7 @@ void gpr_stack_lockfree_push(gpr_stack_lockfree *stack, int entry) { } while (!gpr_atm_rel_cas(&(stack->head.atm), head.atm, newhead.atm)); /* Use rel_cas above to make sure that entry index is set properly */ + return head.atm == INVALID_ENTRY_INDEX; } int gpr_stack_lockfree_pop(gpr_stack_lockfree *stack) { diff --git a/src/core/support/stack_lockfree.h b/src/core/support/stack_lockfree.h index 7919ef38ccdc57c9ff26dc05565012b6b932742a..4da3572deb8913536044628cbeef410e9ef14a9c 100644 --- a/src/core/support/stack_lockfree.h +++ b/src/core/support/stack_lockfree.h @@ -42,7 +42,8 @@ gpr_stack_lockfree *gpr_stack_lockfree_create(int entries); void gpr_stack_lockfree_destroy(gpr_stack_lockfree *); /* Pass in a valid entry number for the next stack entry */ -void gpr_stack_lockfree_push(gpr_stack_lockfree *, int entry); +/* Returns 1 if this is the first element on the stack, 0 otherwise */ +int gpr_stack_lockfree_push(gpr_stack_lockfree *, int entry); /* Returns -1 on empty or the actual entry number */ int gpr_stack_lockfree_pop(gpr_stack_lockfree *);