migration/multifd: multifd_send_kick_main()
When a multifd sender thread hit errors, it always needs to kick the main
thread by kicking all the semaphores that it can be waiting upon.
Provide a helper for it and deduplicate the code.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
diff --git a/migration/multifd.c b/migration/multifd.c
index eee2586..b8d2c96 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -373,6 +373,18 @@
} *multifd_send_state;
/*
+ * The migration thread can wait on either of the two semaphores. This
+ * function can be used to kick the main thread out of waiting on either of
+ * them. Should mostly only be called when something wrong happened with
+ * the current multifd send thread.
+ */
+static void multifd_send_kick_main(MultiFDSendParams *p)
+{
+ qemu_sem_post(&p->sem_sync);
+ qemu_sem_post(&multifd_send_state->channels_ready);
+}
+
+/*
* How we use multifd_send_state->pages and channel->pages?
*
* We create a pages for each channel, and a main one. Each time that
@@ -739,8 +751,7 @@
assert(local_err);
trace_multifd_send_error(p->id);
multifd_send_terminate_threads(local_err);
- qemu_sem_post(&p->sem_sync);
- qemu_sem_post(&multifd_send_state->channels_ready);
+ multifd_send_kick_main(p);
error_free(local_err);
}
@@ -781,8 +792,7 @@
* is not created, and then tell who pay attention to me.
*/
p->quit = true;
- qemu_sem_post(&multifd_send_state->channels_ready);
- qemu_sem_post(&p->sem_sync);
+ multifd_send_kick_main(p);
error_free(err);
}
@@ -852,8 +862,7 @@
{
migrate_set_error(migrate_get_current(), err);
/* Error happen, we need to tell who pay attention to me */
- qemu_sem_post(&multifd_send_state->channels_ready);
- qemu_sem_post(&p->sem_sync);
+ multifd_send_kick_main(p);
/*
* Although multifd_send_thread is not created, but main migration
* thread need to judge whether it is running, so we need to mark
