diff options
| -rw-r--r-- | hmp-commands.hx | 1 | ||||
| -rw-r--r-- | monitor/hmp-cmds.c | 3 | ||||
| -rw-r--r-- | qapi/ui.json | 3 | ||||
| -rw-r--r-- | ui/console.c | 32 |
4 files changed, 34 insertions, 5 deletions
diff --git a/hmp-commands.hx b/hmp-commands.hx index cd06838..ff2d7aa 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -254,6 +254,7 @@ ERST .help = "save screen from head 'head' of display device 'device' " "into PPM image 'filename'", .cmd = hmp_screendump, + .coroutine = true, }, SRST diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c index 56e9bad..a6a6684 100644 --- a/monitor/hmp-cmds.c +++ b/monitor/hmp-cmds.c @@ -1762,7 +1762,8 @@ err_out: goto out; } -void hmp_screendump(Monitor *mon, const QDict *qdict) +void coroutine_fn +hmp_screendump(Monitor *mon, const QDict *qdict) { const char *filename = qdict_get_str(qdict, "filename"); const char *id = qdict_get_try_str(qdict, "device"); diff --git a/qapi/ui.json b/qapi/ui.json index 9d67210..6c7b33c 100644 --- a/qapi/ui.json +++ b/qapi/ui.json @@ -98,7 +98,8 @@ # ## { 'command': 'screendump', - 'data': {'filename': 'str', '*device': 'str', '*head': 'int'} } + 'data': {'filename': 'str', '*device': 'str', '*head': 'int'}, + 'coroutine': true } ## # == Spice diff --git a/ui/console.c b/ui/console.c index 96dd212..e8e5970 100644 --- a/ui/console.c +++ b/ui/console.c @@ -168,6 +168,7 @@ struct QemuConsole { QEMUFIFO out_fifo; uint8_t out_fifo_buf[16]; QEMUTimer *kbd_timer; + CoQueue dump_queue; QTAILQ_ENTRY(QemuConsole) next; }; @@ -263,6 +264,7 @@ static void gui_setup_refresh(DisplayState *ds) void graphic_hw_update_done(QemuConsole *con) { + qemu_co_queue_restart_all(&con->dump_queue); } void graphic_hw_update(QemuConsole *con) @@ -340,8 +342,15 @@ static bool ppm_save(int fd, pixman_image_t *image, Error **errp) return true; } -void qmp_screendump(const char *filename, bool has_device, const char *device, - bool has_head, int64_t head, Error **errp) +static void graphic_hw_update_bh(void *con) +{ + graphic_hw_update(con); +} + +/* Safety: coroutine-only, concurrent-coroutine safe, main thread only */ +void coroutine_fn +qmp_screendump(const char *filename, bool has_device, const char *device, + bool has_head, int64_t head, Error **errp) { g_autoptr(pixman_image_t) image = NULL; QemuConsole *con; @@ -366,7 +375,18 @@ void qmp_screendump(const char *filename, bool has_device, const char *device, } } - graphic_hw_update(con); + if (qemu_co_queue_empty(&con->dump_queue)) { + /* Defer the update, it will restart the pending coroutines */ + aio_bh_schedule_oneshot(qemu_get_aio_context(), + graphic_hw_update_bh, con); + } + qemu_co_queue_wait(&con->dump_queue, NULL); + + /* + * All pending coroutines are woken up, while the BQL is held. No + * further graphic update are possible until it is released. Take + * an image ref before that. + */ surface = qemu_console_surface(con); if (!surface) { error_setg(errp, "no surface"); @@ -381,6 +401,11 @@ void qmp_screendump(const char *filename, bool has_device, const char *device, return; } + /* + * The image content could potentially be updated as the coroutine + * yields and releases the BQL. It could produce corrupted dump, but + * it should be otherwise safe. + */ if (!ppm_save(fd, image, errp)) { qemu_unlink(filename); } @@ -1297,6 +1322,7 @@ static QemuConsole *new_console(DisplayState *ds, console_type_t console_type, obj = object_new(TYPE_QEMU_CONSOLE); s = QEMU_CONSOLE(obj); + qemu_co_queue_init(&s->dump_queue); s->head = head; object_property_add_link(obj, "device", TYPE_DEVICE, (Object **)&s->device, |