4 files changed, 29 insertions, 36 deletions

diff --git a/include/block/coroutine_int.h b/include/block/coroutine_int.h
index 17eb71e723..f133d65af8 100644
--- a/include/block/coroutine_int.h
+++ b/include/block/coroutine_int.h
@@ -38,6 +38,9 @@ struct Coroutine {
     void *entry_arg;
     Coroutine *caller;
     QSLIST_ENTRY(Coroutine) pool_next;
+
+    /* Coroutines that should be woken up when we yield or terminate */
+    QTAILQ_HEAD(, Coroutine) co_queue_wakeup;
     QTAILQ_ENTRY(Coroutine) co_queue_next;
 };
 
@@ -45,5 +48,6 @@ Coroutine *qemu_coroutine_new(void);
 void qemu_coroutine_delete(Coroutine *co);
 CoroutineAction qemu_coroutine_switch(Coroutine *from, Coroutine *to,
                                       CoroutineAction action);
+void coroutine_fn qemu_co_queue_run_restart(Coroutine *co);
 
 #endif
diff --git a/qemu-coroutine-lock.c b/qemu-coroutine-lock.c
index 86efe1f86a..d9fea4989d 100644
--- a/qemu-coroutine-lock.c
+++ b/qemu-coroutine-lock.c
@@ -26,39 +26,11 @@
 #include "block/coroutine.h"
 #include "block/coroutine_int.h"
 #include "qemu/queue.h"
-#include "block/aio.h"
 #include "trace.h"
 
-/* Coroutines are awoken from a BH to allow the current coroutine to complete
- * its flow of execution.  The BH may run after the CoQueue has been destroyed,
- * so keep BH data in a separate heap-allocated struct.
- */
-typedef struct {
-    QEMUBH *bh;
-    QTAILQ_HEAD(, Coroutine) entries;
-} CoQueueNextData;
-
-static void qemu_co_queue_next_bh(void *opaque)
-{
-    CoQueueNextData *data = opaque;
-    Coroutine *next;
-
-    trace_qemu_co_queue_next_bh();
-    while ((next = QTAILQ_FIRST(&data->entries))) {
-        QTAILQ_REMOVE(&data->entries, next, co_queue_next);
-        qemu_coroutine_enter(next, NULL);
-    }
-
-    qemu_bh_delete(data->bh);
-    g_slice_free(CoQueueNextData, data);
-}
-
 void qemu_co_queue_init(CoQueue *queue)
 {
     QTAILQ_INIT(&queue->entries);
-
-    /* This will be exposed to callers once there are multiple AioContexts */
-    queue->ctx = qemu_get_aio_context();
 }
 
 void coroutine_fn qemu_co_queue_wait(CoQueue *queue)
@@ -77,23 +49,37 @@ void coroutine_fn qemu_co_queue_wait_insert_head(CoQueue *queue)
     assert(qemu_in_coroutine());
 }
 
+/**
+ * qemu_co_queue_run_restart:
+ *
+ * Enter each coroutine that was previously marked for restart by
+ * qemu_co_queue_next() or qemu_co_queue_restart_all().  This function is
+ * invoked by the core coroutine code when the current coroutine yields or
+ * terminates.
+ */
+void qemu_co_queue_run_restart(Coroutine *co)
+{
+    Coroutine *next;
+
+    trace_qemu_co_queue_run_restart(co);
+    while ((next = QTAILQ_FIRST(&co->co_queue_wakeup))) {
+        QTAILQ_REMOVE(&co->co_queue_wakeup, next, co_queue_next);
+        qemu_coroutine_enter(next, NULL);
+    }
+}
+
 static bool qemu_co_queue_do_restart(CoQueue *queue, bool single)
 {
+    Coroutine *self = qemu_coroutine_self();
     Coroutine *next;
-    CoQueueNextData *data;
 
     if (QTAILQ_EMPTY(&queue->entries)) {
         return false;
     }
 
-    data = g_slice_new(CoQueueNextData);
-    data->bh = aio_bh_new(queue->ctx, qemu_co_queue_next_bh, data);
-    QTAILQ_INIT(&data->entries);
-    qemu_bh_schedule(data->bh);
-
     while ((next = QTAILQ_FIRST(&queue->entries)) != NULL) {
         QTAILQ_REMOVE(&queue->entries, next, co_queue_next);
-        QTAILQ_INSERT_TAIL(&data->entries, next, co_queue_next);
+        QTAILQ_INSERT_TAIL(&self->co_queue_wakeup, next, co_queue_next);
         trace_qemu_co_queue_next(next);
         if (single) {
             break;
diff --git a/qemu-coroutine.c b/qemu-coroutine.c
index 60ac79e680..423430d3a0 100644
--- a/qemu-coroutine.c
+++ b/qemu-coroutine.c
@@ -45,6 +45,7 @@ Coroutine *qemu_coroutine_create(CoroutineEntry *entry)
     }
 
     co->entry = entry;
+    QTAILQ_INIT(&co->co_queue_wakeup);
     return co;
 }
 
@@ -87,6 +88,8 @@ static void coroutine_swap(Coroutine *from, Coroutine *to)
 
     ret = qemu_coroutine_switch(from, to, COROUTINE_YIELD);
 
+    qemu_co_queue_run_restart(to);
+
     switch (ret) {
     case COROUTINE_YIELD:
         return;
diff --git a/trace-events b/trace-events
index 9c73931f37..f51408aeb2 100644
--- a/trace-events
+++ b/trace-events
@@ -825,7 +825,7 @@ qemu_coroutine_yield(void *from, void *to) "from %p to %p"
 qemu_coroutine_terminate(void *co) "self %p"
 
 # qemu-coroutine-lock.c
-qemu_co_queue_next_bh(void) ""
+qemu_co_queue_run_restart(void *co) "co %p"
 qemu_co_queue_next(void *nxt) "next %p"
 qemu_co_mutex_lock_entry(void *mutex, void *self) "mutex %p self %p"
 qemu_co_mutex_lock_return(void *mutex, void *self) "mutex %p self %p"