This will be used by BDRV_POLL_WHILE (and thus by bdrv_drain)
to choose how to wait for I/O completion.
Reviewed-by: Fam Zheng <f...@redhat.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
include/block/aio.h | 18 ++++++++++++++++++
iothread.c | 9 +++++++++
stubs/Makefile.objs | 1 +
stubs/iothread.c | 8 ++++++++
4 files changed, 36 insertions(+)
create mode 100644 stubs/iothread.c
diff --git a/include/block/aio.h b/include/block/aio.h
index b9fe2cb..040b3b1 100644
--- a/include/block/aio.h
+++ b/include/block/aio.h
@@ -453,6 +453,24 @@ static inline bool aio_node_check(AioContext *ctx, bool
is_external)
}
/**
+ * Return the AioContext whose event loop runs in the current thread.
+ *
+ * If called from an IOThread this will be the IOThread's AioContext. If
+ * called from another thread it will be the main loop AioContext.
+ */
+AioContext *qemu_get_current_aio_context(void);
+
+/**
+ * @ctx: the aio context
+ *
+ * Return whether we are running in the I/O thread that manages @ctx.
+ */
+static inline bool aio_context_in_iothread(AioContext *ctx)
+{
+ return ctx == qemu_get_current_aio_context();
+}
+
+/**
* aio_context_setup:
* @ctx: the aio context
*
diff --git a/iothread.c b/iothread.c
index fbeb8de..62c8796 100644
--- a/iothread.c
+++ b/iothread.c
@@ -20,6 +20,7 @@
#include "qmp-commands.h"
#include "qemu/error-report.h"
#include "qemu/rcu.h"
+#include "qemu/main-loop.h"
typedef ObjectClass IOThreadClass;
@@ -28,6 +29,13 @@ typedef ObjectClass IOThreadClass;
#define IOTHREAD_CLASS(klass) \
OBJECT_CLASS_CHECK(IOThreadClass, klass, TYPE_IOTHREAD)
+static __thread IOThread *my_iothread;
+
+AioContext *qemu_get_current_aio_context(void)
+{
+ return my_iothread ? my_iothread->ctx : qemu_get_aio_context();
+}
+
static void *iothread_run(void *opaque)
{
IOThread *iothread = opaque;
@@ -35,6 +43,7 @@ static void *iothread_run(void *opaque)
rcu_register_thread();
+ my_iothread = iothread;
qemu_mutex_lock(&iothread->init_done_lock);
iothread->thread_id = qemu_get_thread_id();
qemu_cond_signal(&iothread->init_done_cond);
diff --git a/stubs/Makefile.objs b/stubs/Makefile.objs
index c5850e8..84b9d9e 100644
--- a/stubs/Makefile.objs
+++ b/stubs/Makefile.objs
@@ -17,6 +17,7 @@ stub-obj-y += gdbstub.o
stub-obj-y += get-fd.o
stub-obj-y += get-next-serial.o
stub-obj-y += get-vm-name.o
+stub-obj-y += iothread.o
stub-obj-y += iothread-lock.o
stub-obj-y += is-daemonized.o
stub-obj-y += machine-init-done.o
diff --git a/stubs/iothread.c b/stubs/iothread.c
new file mode 100644
index 0000000..8cc9e28
--- /dev/null
+++ b/stubs/iothread.c
@@ -0,0 +1,8 @@
+#include "qemu/osdep.h"
+#include "block/aio.h"
+#include "qemu/main-loop.h"
+
+AioContext *qemu_get_current_aio_context(void)
+{
+ return qemu_get_aio_context();
+}
--
2.7.4
