2  * urcu-mb.c
24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
33 #include "qemu/main-loop.h"
87             qatomic_set(&index->waiting, true);  in wait_for_readers()
90         /* Here, order the stores to index->waiting before the loads of  in wait_for_readers()
91          * index->ctr.  Pairs with smp_mb_placeholder() in rcu_read_unlock(),  in wait_for_readers()
92          * ensuring that the loads of index->ctr are sequentially consistent.  in wait_for_readers()
96          * on architectures with 32-bit longs; see synchronize_rcu().  in wait_for_readers()
101             if (!rcu_gp_ongoing(&index->ctr)) {  in wait_for_readers()
108                 qatomic_set(&index->waiting, false);  in wait_for_readers()
110                 notifier_list_notify(&index->force_rcu, NULL);  in wait_for_readers()
124          * thread must exit its RCU read-side critical section before  in wait_for_readers()
129          * rcu_unregister_thread() may remove nodes from &qsreaders instead  in wait_for_readers()
148     /* Write RCU-protected pointers before reading p_rcu_reader->ctr.  in synchronize_rcu()
151      * Also orders write to RCU-protected pointers before  in synchronize_rcu()
159             /* For architectures with 32-bit longs, a two-subphases algorithm  in synchronize_rcu()
162              * Switch parity: 0 -> 1, 1 -> 0.  in synchronize_rcu()
179 /* Multi-producer, single-consumer queue based on urcu/static/wfqueue.h
191     node->next = NULL;  in enqueue()
198     old_tail = qatomic_xchg(&tail, &node->next);  in enqueue()
201      * ... until it is pointed to from another item in the list.  in enqueue()
222     next = qatomic_load_acquire(&node->next);  in try_dequeue()
300             n--;  in call_rcu_thread()
301             node->func(node);  in call_rcu_thread()
310     node->func = func;  in call_rcu1()
325     qemu_event_set(&event->drain_complete_event);  in drain_rcu_callback()
375     assert(get_ptr_rcu_reader()->ctr == 0);  in rcu_register_thread()
391     notifier_list_add(&get_ptr_rcu_reader()->force_rcu, n);  in rcu_add_force_rcu_notifier()
430     atfork_depth--;  in rcu_disable_atfork()