aboutsummaryrefslogtreecommitdiff
path: root/iothread.c
diff options
context:
space:
mode:
authorStefan Hajnoczi <stefanha@redhat.com>2014-02-27 11:48:41 +0100
committerStefan Hajnoczi <stefanha@redhat.com>2014-03-13 14:42:24 +0100
commit88eb7c29e4320597d2f246adf731f0aac97cfbcc (patch)
tree2044aec8594d144fe48380f095110abd1bf97199 /iothread.c
parent48ff269272f18d2b8fa53cb08365df417588f585 (diff)
downloadqemu-arm-88eb7c29e4320597d2f246adf731f0aac97cfbcc.tar.gz
iothread: stash thread ID away
Keep the thread ID around so we can report it via QMP. There's only one problem: qemu_get_thread_id() (gettid() wrapper on Linux) must be called from the thread itself. There is no way to get the thread ID outside the thread. This patch uses a condvar to wait for iothread_run() to populate the thread_id inside the thread. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Diffstat (limited to 'iothread.c')
-rw-r--r--iothread.c22
1 files changed, 22 insertions, 0 deletions
diff --git a/iothread.c b/iothread.c
index f263ee2744..f90bbc339e 100644
--- a/iothread.c
+++ b/iothread.c
@@ -26,7 +26,10 @@ struct IOThread {
QemuThread thread;
AioContext *ctx;
+ QemuMutex init_done_lock;
+ QemuCond init_done_cond; /* is thread initialization done? */
bool stopping;
+ int thread_id;
};
#define IOTHREAD_GET_CLASS(obj) \
@@ -38,6 +41,11 @@ static void *iothread_run(void *opaque)
{
IOThread *iothread = opaque;
+ qemu_mutex_lock(&iothread->init_done_lock);
+ iothread->thread_id = qemu_get_thread_id();
+ qemu_cond_signal(&iothread->init_done_cond);
+ qemu_mutex_unlock(&iothread->init_done_lock);
+
while (!iothread->stopping) {
aio_context_acquire(iothread->ctx);
while (!iothread->stopping && aio_poll(iothread->ctx, true)) {
@@ -55,6 +63,8 @@ static void iothread_instance_finalize(Object *obj)
iothread->stopping = true;
aio_notify(iothread->ctx);
qemu_thread_join(&iothread->thread);
+ qemu_cond_destroy(&iothread->init_done_cond);
+ qemu_mutex_destroy(&iothread->init_done_lock);
aio_context_unref(iothread->ctx);
}
@@ -64,12 +74,24 @@ static void iothread_complete(UserCreatable *obj, Error **errp)
iothread->stopping = false;
iothread->ctx = aio_context_new();
+ iothread->thread_id = -1;
+
+ qemu_mutex_init(&iothread->init_done_lock);
+ qemu_cond_init(&iothread->init_done_cond);
/* This assumes we are called from a thread with useful CPU affinity for us
* to inherit.
*/
qemu_thread_create(&iothread->thread, "iothread", iothread_run,
iothread, QEMU_THREAD_JOINABLE);
+
+ /* Wait for initialization to complete */
+ qemu_mutex_lock(&iothread->init_done_lock);
+ while (iothread->thread_id == -1) {
+ qemu_cond_wait(&iothread->init_done_cond,
+ &iothread->init_done_lock);
+ }
+ qemu_mutex_unlock(&iothread->init_done_lock);
}
static void iothread_class_init(ObjectClass *klass, void *class_data)