static void
test_atomic_flag(void)
{
pg_atomic_flag flag;
pg_atomic_init_flag(&flag);
if (!pg_atomic_unlocked_test_flag(&flag))
elog(ERROR, "flag: unexpectedly set");
if (!pg_atomic_test_set_flag(&flag))
elog(ERROR, "flag: couldn't set");
if (pg_atomic_unlocked_test_flag(&flag))
elog(ERROR, "flag: unexpectedly unset");
if (pg_atomic_test_set_flag(&flag))
elog(ERROR, "flag: set spuriously #2");
pg_atomic_clear_flag(&flag);
if (!pg_atomic_unlocked_test_flag(&flag))
elog(ERROR, "flag: unexpectedly set #2");
if (!pg_atomic_test_set_flag(&flag))
elog(ERROR, "flag: couldn't set");
pg_atomic_clear_flag(&flag);
}
Datum cfs_start_gc(PG_FUNCTION_ARGS)
{
int i = 0;
if (cfs_gc_workers == 0 && pg_atomic_test_set_flag(&cfs_state->gc_started))
{
int j;
BackgroundWorkerHandle** handles;
cfs_stop = true; /* do just one iteration */
cfs_state->max_iterations = 1;
cfs_state->n_workers = PG_GETARG_INT32(0);
handles = (BackgroundWorkerHandle**)palloc(cfs_state->n_workers*sizeof(BackgroundWorkerHandle*));
for (i = 0; i < cfs_state->n_workers; i++) {
BackgroundWorker worker;
MemSet(&worker, 0, sizeof(worker));
sprintf(worker.bgw_name, "cfs-worker-%d", i);
worker.bgw_flags = BGWORKER_SHMEM_ACCESS;
worker.bgw_start_time = BgWorkerStart_ConsistentState;
worker.bgw_restart_time = 1;
worker.bgw_main = cfs_bgworker_main;
worker.bgw_main_arg = Int32GetDatum(i);
if (!RegisterDynamicBackgroundWorker(&worker, &handles[i])) {
break;
}
}
for (j = 0; j < i; j++) {
WaitForBackgroundWorkerShutdown(handles[j]);
}
pfree(handles);
pg_atomic_clear_flag(&cfs_state->gc_started);
}
PG_RETURN_INT32(i);
}