From 42b6c93c36d818a75344d16e353144a0e609e01e Mon Sep 17 00:00:00 2001 From: Craig Tiller Date: Thu, 30 Jul 2015 09:59:25 -0700 Subject: Make TSAN happy with our lock free stack --- src/core/support/stack_lockfree.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'src/core') diff --git a/src/core/support/stack_lockfree.c b/src/core/support/stack_lockfree.c index f24e272207..bc741f8c70 100644 --- a/src/core/support/stack_lockfree.c +++ b/src/core/support/stack_lockfree.c @@ -95,6 +95,8 @@ gpr_stack_lockfree *gpr_stack_lockfree_create(int entries) { memset(&stack->pushed, 0, sizeof(stack->pushed)); #endif + GPR_ASSERT(sizeof(stack->entries->atm) == sizeof(stack->entries->contents)); + /* Point the head at reserved dummy entry */ stack->head.contents.index = INVALID_ENTRY_INDEX; return stack; @@ -108,11 +110,15 @@ void gpr_stack_lockfree_destroy(gpr_stack_lockfree *stack) { int gpr_stack_lockfree_push(gpr_stack_lockfree *stack, int entry) { lockfree_node head; lockfree_node newhead; + lockfree_node curent; + lockfree_node newent; /* First fill in the entry's index and aba ctr for new head */ newhead.contents.index = (gpr_uint16)entry; /* Also post-increment the aba_ctr */ - newhead.contents.aba_ctr = stack->entries[entry].contents.aba_ctr++; + curent.atm = gpr_atm_no_barrier_load(&stack->entries[entry].atm); + newhead.contents.aba_ctr = ++curent.contents.aba_ctr; + gpr_atm_no_barrier_store(&stack->entries[entry].atm, curent.atm); #ifndef NDEBUG /* Check for double push */ @@ -131,7 +137,9 @@ int gpr_stack_lockfree_push(gpr_stack_lockfree *stack, int entry) { /* Atomically get the existing head value for use */ head.atm = gpr_atm_no_barrier_load(&(stack->head.atm)); /* Point to it */ - stack->entries[entry].contents.index = head.contents.index; + newent.atm = gpr_atm_no_barrier_load(&stack->entries[entry].atm); + newent.contents.index = head.contents.index; + gpr_atm_no_barrier_store(&stack->entries[entry].atm, newent.atm); } 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.contents.index == INVALID_ENTRY_INDEX; -- cgit v1.2.3