target/arm: Reset btype for direct branches
[qemu/ar7.git] / util / main-loop.c
blob443cb4cfe8bf1cd74c9ce92034b8f375377e1be8
1 /*
2 * QEMU System Emulator
4 * Copyright (c) 2003-2008 Fabrice Bellard
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
25 #include "qemu/osdep.h"
26 #include "qapi/error.h"
27 #include "qemu/cutils.h"
28 #include "qemu/timer.h"
29 #include "qemu/sockets.h" // struct in_addr needed for libslirp.h
30 #include "sysemu/qtest.h"
31 #include "sysemu/cpus.h"
32 #include "sysemu/replay.h"
33 #include "slirp/libslirp.h"
34 #include "qemu/main-loop.h"
35 #include "block/aio.h"
36 #include "qemu/error-report.h"
38 #ifndef _WIN32
40 /* If we have signalfd, we mask out the signals we want to handle and then
41 * use signalfd to listen for them. We rely on whatever the current signal
42 * handler is to dispatch the signals when we receive them.
44 static void sigfd_handler(void *opaque)
46 int fd = (intptr_t)opaque;
47 struct qemu_signalfd_siginfo info;
48 struct sigaction action;
49 ssize_t len;
51 while (1) {
52 do {
53 len = read(fd, &info, sizeof(info));
54 } while (len == -1 && errno == EINTR);
56 if (len == -1 && errno == EAGAIN) {
57 break;
60 if (len != sizeof(info)) {
61 printf("read from sigfd returned %zd: %m\n", len);
62 return;
65 sigaction(info.ssi_signo, NULL, &action);
66 if ((action.sa_flags & SA_SIGINFO) && action.sa_sigaction) {
67 sigaction_invoke(&action, &info);
68 } else if (action.sa_handler) {
69 action.sa_handler(info.ssi_signo);
74 static int qemu_signal_init(Error **errp)
76 int sigfd;
77 sigset_t set;
80 * SIG_IPI must be blocked in the main thread and must not be caught
81 * by sigwait() in the signal thread. Otherwise, the cpu thread will
82 * not catch it reliably.
84 sigemptyset(&set);
85 sigaddset(&set, SIG_IPI);
86 sigaddset(&set, SIGIO);
87 sigaddset(&set, SIGALRM);
88 sigaddset(&set, SIGBUS);
89 /* SIGINT cannot be handled via signalfd, so that ^C can be used
90 * to interrupt QEMU when it is being run under gdb. SIGHUP and
91 * SIGTERM are also handled asynchronously, even though it is not
92 * strictly necessary, because they use the same handler as SIGINT.
94 pthread_sigmask(SIG_BLOCK, &set, NULL);
96 sigdelset(&set, SIG_IPI);
97 sigfd = qemu_signalfd(&set);
98 if (sigfd == -1) {
99 error_setg_errno(errp, errno, "failed to create signalfd");
100 return -errno;
103 fcntl_setfl(sigfd, O_NONBLOCK);
105 qemu_set_fd_handler(sigfd, sigfd_handler, NULL, (void *)(intptr_t)sigfd);
107 return 0;
110 #else /* _WIN32 */
112 static int qemu_signal_init(Error **errp)
114 return 0;
116 #endif
118 static AioContext *qemu_aio_context;
119 static QEMUBH *qemu_notify_bh;
121 static void notify_event_cb(void *opaque)
123 /* No need to do anything; this bottom half is only used to
124 * kick the kernel out of ppoll/poll/WaitForMultipleObjects.
128 AioContext *qemu_get_aio_context(void)
130 return qemu_aio_context;
133 void qemu_notify_event(void)
135 if (!qemu_aio_context) {
136 return;
138 qemu_bh_schedule(qemu_notify_bh);
141 static GArray *gpollfds;
143 int qemu_init_main_loop(Error **errp)
145 int ret;
146 GSource *src;
147 Error *local_error = NULL;
149 init_clocks(qemu_timer_notify_cb);
151 ret = qemu_signal_init(errp);
152 if (ret) {
153 return ret;
156 qemu_aio_context = aio_context_new(&local_error);
157 if (!qemu_aio_context) {
158 error_propagate(errp, local_error);
159 return -EMFILE;
161 qemu_notify_bh = qemu_bh_new(notify_event_cb, NULL);
162 gpollfds = g_array_new(FALSE, FALSE, sizeof(GPollFD));
163 src = aio_get_g_source(qemu_aio_context);
164 g_source_set_name(src, "aio-context");
165 g_source_attach(src, NULL);
166 g_source_unref(src);
167 src = iohandler_get_g_source();
168 g_source_set_name(src, "io-handler");
169 g_source_attach(src, NULL);
170 g_source_unref(src);
171 return 0;
174 static int max_priority;
176 #ifndef _WIN32
177 static int glib_pollfds_idx;
178 static int glib_n_poll_fds;
180 static void glib_pollfds_fill(int64_t *cur_timeout)
182 GMainContext *context = g_main_context_default();
183 int timeout = 0;
184 int64_t timeout_ns;
185 int n;
187 g_main_context_prepare(context, &max_priority);
189 glib_pollfds_idx = gpollfds->len;
190 n = glib_n_poll_fds;
191 do {
192 GPollFD *pfds;
193 glib_n_poll_fds = n;
194 g_array_set_size(gpollfds, glib_pollfds_idx + glib_n_poll_fds);
195 pfds = &g_array_index(gpollfds, GPollFD, glib_pollfds_idx);
196 n = g_main_context_query(context, max_priority, &timeout, pfds,
197 glib_n_poll_fds);
198 } while (n != glib_n_poll_fds);
200 if (timeout < 0) {
201 timeout_ns = -1;
202 } else {
203 timeout_ns = (int64_t)timeout * (int64_t)SCALE_MS;
206 *cur_timeout = qemu_soonest_timeout(timeout_ns, *cur_timeout);
209 static void glib_pollfds_poll(void)
211 GMainContext *context = g_main_context_default();
212 GPollFD *pfds = &g_array_index(gpollfds, GPollFD, glib_pollfds_idx);
214 if (g_main_context_check(context, max_priority, pfds, glib_n_poll_fds)) {
215 g_main_context_dispatch(context);
219 #define MAX_MAIN_LOOP_SPIN (1000)
221 static int os_host_main_loop_wait(int64_t timeout)
223 GMainContext *context = g_main_context_default();
224 int ret;
226 g_main_context_acquire(context);
228 glib_pollfds_fill(&timeout);
230 qemu_mutex_unlock_iothread();
231 replay_mutex_unlock();
233 ret = qemu_poll_ns((GPollFD *)gpollfds->data, gpollfds->len, timeout);
235 replay_mutex_lock();
236 qemu_mutex_lock_iothread();
238 glib_pollfds_poll();
240 g_main_context_release(context);
242 return ret;
244 #else
245 /***********************************************************/
246 /* Polling handling */
248 typedef struct PollingEntry {
249 PollingFunc *func;
250 void *opaque;
251 struct PollingEntry *next;
252 } PollingEntry;
254 static PollingEntry *first_polling_entry;
256 int qemu_add_polling_cb(PollingFunc *func, void *opaque)
258 PollingEntry **ppe, *pe;
259 pe = g_malloc0(sizeof(PollingEntry));
260 pe->func = func;
261 pe->opaque = opaque;
262 for(ppe = &first_polling_entry; *ppe != NULL; ppe = &(*ppe)->next);
263 *ppe = pe;
264 return 0;
267 void qemu_del_polling_cb(PollingFunc *func, void *opaque)
269 PollingEntry **ppe, *pe;
270 for(ppe = &first_polling_entry; *ppe != NULL; ppe = &(*ppe)->next) {
271 pe = *ppe;
272 if (pe->func == func && pe->opaque == opaque) {
273 *ppe = pe->next;
274 g_free(pe);
275 break;
280 /***********************************************************/
281 /* Wait objects support */
282 typedef struct WaitObjects {
283 int num;
284 int revents[MAXIMUM_WAIT_OBJECTS + 1];
285 HANDLE events[MAXIMUM_WAIT_OBJECTS + 1];
286 WaitObjectFunc *func[MAXIMUM_WAIT_OBJECTS + 1];
287 void *opaque[MAXIMUM_WAIT_OBJECTS + 1];
288 } WaitObjects;
290 static WaitObjects wait_objects = {0};
292 int qemu_add_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
294 WaitObjects *w = &wait_objects;
295 if (w->num >= MAXIMUM_WAIT_OBJECTS) {
296 return -1;
298 w->events[w->num] = handle;
299 w->func[w->num] = func;
300 w->opaque[w->num] = opaque;
301 w->revents[w->num] = 0;
302 w->num++;
303 return 0;
306 void qemu_del_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
308 int i, found;
309 WaitObjects *w = &wait_objects;
311 found = 0;
312 for (i = 0; i < w->num; i++) {
313 if (w->events[i] == handle) {
314 found = 1;
316 if (found) {
317 w->events[i] = w->events[i + 1];
318 w->func[i] = w->func[i + 1];
319 w->opaque[i] = w->opaque[i + 1];
320 w->revents[i] = w->revents[i + 1];
323 if (found) {
324 w->num--;
328 void qemu_fd_register(int fd)
330 WSAEventSelect(fd, event_notifier_get_handle(&qemu_aio_context->notifier),
331 FD_READ | FD_ACCEPT | FD_CLOSE |
332 FD_CONNECT | FD_WRITE | FD_OOB);
335 static int pollfds_fill(GArray *pollfds, fd_set *rfds, fd_set *wfds,
336 fd_set *xfds)
338 int nfds = -1;
339 int i;
341 for (i = 0; i < pollfds->len; i++) {
342 GPollFD *pfd = &g_array_index(pollfds, GPollFD, i);
343 int fd = pfd->fd;
344 int events = pfd->events;
345 if (events & G_IO_IN) {
346 FD_SET(fd, rfds);
347 nfds = MAX(nfds, fd);
349 if (events & G_IO_OUT) {
350 FD_SET(fd, wfds);
351 nfds = MAX(nfds, fd);
353 if (events & G_IO_PRI) {
354 FD_SET(fd, xfds);
355 nfds = MAX(nfds, fd);
358 return nfds;
361 static void pollfds_poll(GArray *pollfds, int nfds, fd_set *rfds,
362 fd_set *wfds, fd_set *xfds)
364 int i;
366 for (i = 0; i < pollfds->len; i++) {
367 GPollFD *pfd = &g_array_index(pollfds, GPollFD, i);
368 int fd = pfd->fd;
369 int revents = 0;
371 if (FD_ISSET(fd, rfds)) {
372 revents |= G_IO_IN;
374 if (FD_ISSET(fd, wfds)) {
375 revents |= G_IO_OUT;
377 if (FD_ISSET(fd, xfds)) {
378 revents |= G_IO_PRI;
380 pfd->revents = revents & pfd->events;
384 static int os_host_main_loop_wait(int64_t timeout)
386 GMainContext *context = g_main_context_default();
387 GPollFD poll_fds[1024 * 2]; /* this is probably overkill */
388 int select_ret = 0;
389 int g_poll_ret, ret, i, n_poll_fds;
390 PollingEntry *pe;
391 WaitObjects *w = &wait_objects;
392 gint poll_timeout;
393 int64_t poll_timeout_ns;
394 static struct timeval tv0;
395 fd_set rfds, wfds, xfds;
396 int nfds;
398 g_main_context_acquire(context);
400 /* XXX: need to suppress polling by better using win32 events */
401 ret = 0;
402 for (pe = first_polling_entry; pe != NULL; pe = pe->next) {
403 ret |= pe->func(pe->opaque);
405 if (ret != 0) {
406 g_main_context_release(context);
407 return ret;
410 FD_ZERO(&rfds);
411 FD_ZERO(&wfds);
412 FD_ZERO(&xfds);
413 nfds = pollfds_fill(gpollfds, &rfds, &wfds, &xfds);
414 if (nfds >= 0) {
415 select_ret = select(nfds + 1, &rfds, &wfds, &xfds, &tv0);
416 if (select_ret != 0) {
417 timeout = 0;
419 if (select_ret > 0) {
420 pollfds_poll(gpollfds, nfds, &rfds, &wfds, &xfds);
424 g_main_context_prepare(context, &max_priority);
425 n_poll_fds = g_main_context_query(context, max_priority, &poll_timeout,
426 poll_fds, ARRAY_SIZE(poll_fds));
427 g_assert(n_poll_fds <= ARRAY_SIZE(poll_fds));
429 for (i = 0; i < w->num; i++) {
430 poll_fds[n_poll_fds + i].fd = (DWORD_PTR)w->events[i];
431 poll_fds[n_poll_fds + i].events = G_IO_IN;
434 if (poll_timeout < 0) {
435 poll_timeout_ns = -1;
436 } else {
437 poll_timeout_ns = (int64_t)poll_timeout * (int64_t)SCALE_MS;
440 poll_timeout_ns = qemu_soonest_timeout(poll_timeout_ns, timeout);
442 qemu_mutex_unlock_iothread();
444 replay_mutex_unlock();
446 g_poll_ret = qemu_poll_ns(poll_fds, n_poll_fds + w->num, poll_timeout_ns);
448 replay_mutex_lock();
450 qemu_mutex_lock_iothread();
451 if (g_poll_ret > 0) {
452 for (i = 0; i < w->num; i++) {
453 w->revents[i] = poll_fds[n_poll_fds + i].revents;
455 for (i = 0; i < w->num; i++) {
456 if (w->revents[i] && w->func[i]) {
457 w->func[i](w->opaque[i]);
462 if (g_main_context_check(context, max_priority, poll_fds, n_poll_fds)) {
463 g_main_context_dispatch(context);
466 g_main_context_release(context);
468 return select_ret || g_poll_ret;
470 #endif
472 void main_loop_wait(int nonblocking)
474 int ret;
475 uint32_t timeout = UINT32_MAX;
476 int64_t timeout_ns;
478 if (nonblocking) {
479 timeout = 0;
482 /* poll any events */
483 g_array_set_size(gpollfds, 0); /* reset for new iteration */
484 /* XXX: separate device handlers from system ones */
485 slirp_pollfds_fill(gpollfds, &timeout);
487 if (timeout == UINT32_MAX) {
488 timeout_ns = -1;
489 } else {
490 timeout_ns = (uint64_t)timeout * (int64_t)(SCALE_MS);
493 timeout_ns = qemu_soonest_timeout(timeout_ns,
494 timerlistgroup_deadline_ns(
495 &main_loop_tlg));
497 ret = os_host_main_loop_wait(timeout_ns);
498 slirp_pollfds_poll(gpollfds, (ret < 0));
500 /* CPU thread can infinitely wait for event after
501 missing the warp */
502 qemu_start_warp_timer();
503 qemu_clock_run_all_timers();
506 /* Functions to operate on the main QEMU AioContext. */
508 QEMUBH *qemu_bh_new(QEMUBHFunc *cb, void *opaque)
510 return aio_bh_new(qemu_aio_context, cb, opaque);