Paolo Bonzini | 0c330a7 | 2017-02-13 14:52:19 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Event loop thread implementation for unit tests |
| 3 | * |
| 4 | * Copyright Red Hat Inc., 2013, 2016 |
| 5 | * |
| 6 | * Authors: |
| 7 | * Stefan Hajnoczi <stefanha@redhat.com> |
| 8 | * Paolo Bonzini <pbonzini@redhat.com> |
| 9 | * |
| 10 | * This work is licensed under the terms of the GNU GPL, version 2 or later. |
| 11 | * See the COPYING file in the top-level directory. |
| 12 | * |
| 13 | */ |
| 14 | |
| 15 | #include "qemu/osdep.h" |
| 16 | #include "qapi/error.h" |
| 17 | #include "block/aio.h" |
| 18 | #include "qemu/main-loop.h" |
| 19 | #include "qemu/rcu.h" |
| 20 | #include "iothread.h" |
| 21 | |
| 22 | struct IOThread { |
| 23 | AioContext *ctx; |
| 24 | |
| 25 | QemuThread thread; |
| 26 | QemuMutex init_done_lock; |
| 27 | QemuCond init_done_cond; /* is thread initialization done? */ |
| 28 | bool stopping; |
| 29 | }; |
| 30 | |
| 31 | static __thread IOThread *my_iothread; |
| 32 | |
| 33 | AioContext *qemu_get_current_aio_context(void) |
| 34 | { |
| 35 | return my_iothread ? my_iothread->ctx : qemu_get_aio_context(); |
| 36 | } |
| 37 | |
| 38 | static void *iothread_run(void *opaque) |
| 39 | { |
| 40 | IOThread *iothread = opaque; |
| 41 | |
| 42 | rcu_register_thread(); |
| 43 | |
| 44 | my_iothread = iothread; |
| 45 | qemu_mutex_lock(&iothread->init_done_lock); |
| 46 | iothread->ctx = aio_context_new(&error_abort); |
| 47 | qemu_cond_signal(&iothread->init_done_cond); |
| 48 | qemu_mutex_unlock(&iothread->init_done_lock); |
| 49 | |
| 50 | while (!atomic_read(&iothread->stopping)) { |
| 51 | aio_poll(iothread->ctx, true); |
| 52 | } |
| 53 | |
| 54 | rcu_unregister_thread(); |
| 55 | return NULL; |
| 56 | } |
| 57 | |
| 58 | void iothread_join(IOThread *iothread) |
| 59 | { |
| 60 | iothread->stopping = true; |
| 61 | aio_notify(iothread->ctx); |
| 62 | qemu_thread_join(&iothread->thread); |
| 63 | qemu_cond_destroy(&iothread->init_done_cond); |
| 64 | qemu_mutex_destroy(&iothread->init_done_lock); |
| 65 | aio_context_unref(iothread->ctx); |
| 66 | g_free(iothread); |
| 67 | } |
| 68 | |
| 69 | IOThread *iothread_new(void) |
| 70 | { |
| 71 | IOThread *iothread = g_new0(IOThread, 1); |
| 72 | |
| 73 | qemu_mutex_init(&iothread->init_done_lock); |
| 74 | qemu_cond_init(&iothread->init_done_cond); |
| 75 | qemu_thread_create(&iothread->thread, NULL, iothread_run, |
| 76 | iothread, QEMU_THREAD_JOINABLE); |
| 77 | |
| 78 | /* Wait for initialization to complete */ |
| 79 | qemu_mutex_lock(&iothread->init_done_lock); |
| 80 | while (iothread->ctx == NULL) { |
| 81 | qemu_cond_wait(&iothread->init_done_cond, |
| 82 | &iothread->init_done_lock); |
| 83 | } |
| 84 | qemu_mutex_unlock(&iothread->init_done_lock); |
| 85 | return iothread; |
| 86 | } |
| 87 | |
| 88 | AioContext *iothread_get_aio_context(IOThread *iothread) |
| 89 | { |
| 90 | return iothread->ctx; |
| 91 | } |