This will be used by bdrv_drain (and indirectly by the synchronous I/O helpers), to choose between aio_poll or QemuEvent.
Reviewed-by: Fam Zheng <f...@redhat.com> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> --- include/block/aio.h | 7 +++++++ iothread.c | 9 +++++++++ stubs/Makefile.objs | 1 + stubs/iothread.c | 8 ++++++++ 4 files changed, 25 insertions(+) create mode 100644 stubs/iothread.c diff --git a/include/block/aio.h b/include/block/aio.h index e086e3b..9434665 100644 --- a/include/block/aio.h +++ b/include/block/aio.h @@ -435,6 +435,13 @@ static inline bool aio_node_check(AioContext *ctx, bool is_external) } /** + * @ctx: the aio context + * + * Return whether we are running in the I/O thread that manages @ctx. + */ +bool aio_context_in_iothread(AioContext *ctx); + +/** * aio_context_setup: * @ctx: the aio context * diff --git a/iothread.c b/iothread.c index f183d38..8d40bb0 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; + +bool aio_context_in_iothread(AioContext *ctx) +{ + return ctx == (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 e922de9..187cee1 100644 --- a/stubs/Makefile.objs +++ b/stubs/Makefile.objs @@ -13,6 +13,7 @@ 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..6c02323 --- /dev/null +++ b/stubs/iothread.c @@ -0,0 +1,8 @@ +#include "qemu/osdep.h" +#include "block/aio.h" +#include "qemu/main-loop.h" + +bool aio_context_in_iothread(AioContext *ctx) +{ + return ctx == qemu_get_aio_context(); +} -- 1.8.3.1