io: Remove redundant read/write_coroutine assignments

qio_channel_yield() now updates ioc->read_write/coroutine and calls qio_channel_set_aio_fd_handlers(), so the code in the handlers has become redundant and can be removed. This does not make a difference in intermediate states because aio_co_wake() really enters the coroutine immediately here: These handlers are never run in coroutine context, and we're in the right AioContext because qio_channel_attach_aio_context() asserts that the handlers are inactive. To make these conditions more obvious, assert the right AioContext. Suggested-by: Paolo Bonzini <[email protected]> Signed-off-by: Kevin Wolf <[email protected]>
YungRaj · Feb 25, 2019 · 2a239e6 · 2a239e6
1 parent 6886cea
commit 2a239e6
Showing 1 changed file with 6 additions and 6 deletions.
diff --git a/io/channel.c b/io/channel.c
@@ -400,15 +400,14 @@ off_t qio_channel_io_seek(QIOChannel *ioc,
 }
 
 
-static void qio_channel_set_aio_fd_handlers(QIOChannel *ioc);
-
 static void qio_channel_restart_read(void *opaque)
 {
     QIOChannel *ioc = opaque;
     Coroutine *co = ioc->read_coroutine;
 
-    ioc->read_coroutine = NULL;
-    qio_channel_set_aio_fd_handlers(ioc);
+    /* Assert that aio_co_wake() reenters the coroutine directly */
+    assert(qemu_get_current_aio_context() ==
+           qemu_coroutine_get_aio_context(co));
     aio_co_wake(co);
 }
 
@@ -417,8 +416,9 @@ static void qio_channel_restart_write(void *opaque)
     QIOChannel *ioc = opaque;
     Coroutine *co = ioc->write_coroutine;
 
-    ioc->write_coroutine = NULL;
-    qio_channel_set_aio_fd_handlers(ioc);
+    /* Assert that aio_co_wake() reenters the coroutine directly */
+    assert(qemu_get_current_aio_context() ==
+           qemu_coroutine_get_aio_context(co));
     aio_co_wake(co);
 }