diff options
Diffstat (limited to 'qemu/main-loop.c')
| -rw-r--r-- | qemu/main-loop.c | 524 |
1 files changed, 0 insertions, 524 deletions
diff --git a/qemu/main-loop.c b/qemu/main-loop.c deleted file mode 100644 index 89a699419..000000000 --- a/qemu/main-loop.c +++ /dev/null @@ -1,524 +0,0 @@ -/* - * QEMU System Emulator - * - * Copyright (c) 2003-2008 Fabrice Bellard - * - * Permission is hereby granted, free of charge, to any person obtaining a copy - * of this software and associated documentation files (the "Software"), to deal - * in the Software without restriction, including without limitation the rights - * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell - * copies of the Software, and to permit persons to whom the Software is - * furnished to do so, subject to the following conditions: - * - * The above copyright notice and this permission notice shall be included in - * all copies or substantial portions of the Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL - * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, - * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN - * THE SOFTWARE. - */ - -#include "qemu/osdep.h" -#include "qapi/error.h" -#include "qemu/cutils.h" -#include "qemu/timer.h" -#include "qemu/sockets.h" // struct in_addr needed for libslirp.h -#include "sysemu/qtest.h" -#include "slirp/libslirp.h" -#include "qemu/main-loop.h" -#include "block/aio.h" - -#ifndef _WIN32 - -#include "qemu/compatfd.h" - -/* If we have signalfd, we mask out the signals we want to handle and then - * use signalfd to listen for them. We rely on whatever the current signal - * handler is to dispatch the signals when we receive them. - */ -static void sigfd_handler(void *opaque) -{ - int fd = (intptr_t)opaque; - struct qemu_signalfd_siginfo info; - struct sigaction action; - ssize_t len; - - while (1) { - do { - len = read(fd, &info, sizeof(info)); - } while (len == -1 && errno == EINTR); - - if (len == -1 && errno == EAGAIN) { - break; - } - - if (len != sizeof(info)) { - printf("read from sigfd returned %zd: %m\n", len); - return; - } - - sigaction(info.ssi_signo, NULL, &action); - if ((action.sa_flags & SA_SIGINFO) && action.sa_sigaction) { - action.sa_sigaction(info.ssi_signo, - (siginfo_t *)&info, NULL); - } else if (action.sa_handler) { - action.sa_handler(info.ssi_signo); - } - } -} - -static int qemu_signal_init(void) -{ - int sigfd; - sigset_t set; - - /* - * SIG_IPI must be blocked in the main thread and must not be caught - * by sigwait() in the signal thread. Otherwise, the cpu thread will - * not catch it reliably. - */ - sigemptyset(&set); - sigaddset(&set, SIG_IPI); - sigaddset(&set, SIGIO); - sigaddset(&set, SIGALRM); - sigaddset(&set, SIGBUS); - /* SIGINT cannot be handled via signalfd, so that ^C can be used - * to interrupt QEMU when it is being run under gdb. SIGHUP and - * SIGTERM are also handled asynchronously, even though it is not - * strictly necessary, because they use the same handler as SIGINT. - */ - pthread_sigmask(SIG_BLOCK, &set, NULL); - - sigdelset(&set, SIG_IPI); - sigfd = qemu_signalfd(&set); - if (sigfd == -1) { - fprintf(stderr, "failed to create signalfd\n"); - return -errno; - } - - fcntl_setfl(sigfd, O_NONBLOCK); - - qemu_set_fd_handler(sigfd, sigfd_handler, NULL, (void *)(intptr_t)sigfd); - - return 0; -} - -#else /* _WIN32 */ - -static int qemu_signal_init(void) -{ - return 0; -} -#endif - -static AioContext *qemu_aio_context; -static QEMUBH *qemu_notify_bh; - -static void notify_event_cb(void *opaque) -{ - /* No need to do anything; this bottom half is only used to - * kick the kernel out of ppoll/poll/WaitForMultipleObjects. - */ -} - -AioContext *qemu_get_aio_context(void) -{ - return qemu_aio_context; -} - -void qemu_notify_event(void) -{ - if (!qemu_aio_context) { - return; - } - qemu_bh_schedule(qemu_notify_bh); -} - -static GArray *gpollfds; - -int qemu_init_main_loop(Error **errp) -{ - int ret; - GSource *src; - Error *local_error = NULL; - - init_clocks(); - - ret = qemu_signal_init(); - if (ret) { - return ret; - } - - qemu_aio_context = aio_context_new(&local_error); - qemu_notify_bh = qemu_bh_new(notify_event_cb, NULL); - if (!qemu_aio_context) { - error_propagate(errp, local_error); - return -EMFILE; - } - gpollfds = g_array_new(FALSE, FALSE, sizeof(GPollFD)); - src = aio_get_g_source(qemu_aio_context); - g_source_attach(src, NULL); - g_source_unref(src); - src = iohandler_get_g_source(); - g_source_attach(src, NULL); - g_source_unref(src); - return 0; -} - -static int max_priority; - -#ifndef _WIN32 -static int glib_pollfds_idx; -static int glib_n_poll_fds; - -static void glib_pollfds_fill(int64_t *cur_timeout) -{ - GMainContext *context = g_main_context_default(); - int timeout = 0; - int64_t timeout_ns; - int n; - - g_main_context_prepare(context, &max_priority); - - glib_pollfds_idx = gpollfds->len; - n = glib_n_poll_fds; - do { - GPollFD *pfds; - glib_n_poll_fds = n; - g_array_set_size(gpollfds, glib_pollfds_idx + glib_n_poll_fds); - pfds = &g_array_index(gpollfds, GPollFD, glib_pollfds_idx); - n = g_main_context_query(context, max_priority, &timeout, pfds, - glib_n_poll_fds); - } while (n != glib_n_poll_fds); - - if (timeout < 0) { - timeout_ns = -1; - } else { - timeout_ns = (int64_t)timeout * (int64_t)SCALE_MS; - } - - *cur_timeout = qemu_soonest_timeout(timeout_ns, *cur_timeout); -} - -static void glib_pollfds_poll(void) -{ - GMainContext *context = g_main_context_default(); - GPollFD *pfds = &g_array_index(gpollfds, GPollFD, glib_pollfds_idx); - - if (g_main_context_check(context, max_priority, pfds, glib_n_poll_fds)) { - g_main_context_dispatch(context); - } -} - -#define MAX_MAIN_LOOP_SPIN (1000) - -static int os_host_main_loop_wait(int64_t timeout) -{ - int ret; - static int spin_counter; - - glib_pollfds_fill(&timeout); - - /* If the I/O thread is very busy or we are incorrectly busy waiting in - * the I/O thread, this can lead to starvation of the BQL such that the - * VCPU threads never run. To make sure we can detect the later case, - * print a message to the screen. If we run into this condition, create - * a fake timeout in order to give the VCPU threads a chance to run. - */ - if (!timeout && (spin_counter > MAX_MAIN_LOOP_SPIN)) { - static bool notified; - - if (!notified && !qtest_driver()) { - fprintf(stderr, - "main-loop: WARNING: I/O thread spun for %d iterations\n", - MAX_MAIN_LOOP_SPIN); - notified = true; - } - - timeout = SCALE_MS; - } - - if (timeout) { - spin_counter = 0; - qemu_mutex_unlock_iothread(); - } else { - spin_counter++; - } - - ret = qemu_poll_ns((GPollFD *)gpollfds->data, gpollfds->len, timeout); - - if (timeout) { - qemu_mutex_lock_iothread(); - } - - glib_pollfds_poll(); - return ret; -} -#else -/***********************************************************/ -/* Polling handling */ - -typedef struct PollingEntry { - PollingFunc *func; - void *opaque; - struct PollingEntry *next; -} PollingEntry; - -static PollingEntry *first_polling_entry; - -int qemu_add_polling_cb(PollingFunc *func, void *opaque) -{ - PollingEntry **ppe, *pe; - pe = g_malloc0(sizeof(PollingEntry)); - pe->func = func; - pe->opaque = opaque; - for(ppe = &first_polling_entry; *ppe != NULL; ppe = &(*ppe)->next); - *ppe = pe; - return 0; -} - -void qemu_del_polling_cb(PollingFunc *func, void *opaque) -{ - PollingEntry **ppe, *pe; - for(ppe = &first_polling_entry; *ppe != NULL; ppe = &(*ppe)->next) { - pe = *ppe; - if (pe->func == func && pe->opaque == opaque) { - *ppe = pe->next; - g_free(pe); - break; - } - } -} - -/***********************************************************/ -/* Wait objects support */ -typedef struct WaitObjects { - int num; - int revents[MAXIMUM_WAIT_OBJECTS + 1]; - HANDLE events[MAXIMUM_WAIT_OBJECTS + 1]; - WaitObjectFunc *func[MAXIMUM_WAIT_OBJECTS + 1]; - void *opaque[MAXIMUM_WAIT_OBJECTS + 1]; -} WaitObjects; - -static WaitObjects wait_objects = {0}; - -int qemu_add_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque) -{ - WaitObjects *w = &wait_objects; - if (w->num >= MAXIMUM_WAIT_OBJECTS) { - return -1; - } - w->events[w->num] = handle; - w->func[w->num] = func; - w->opaque[w->num] = opaque; - w->revents[w->num] = 0; - w->num++; - return 0; -} - -void qemu_del_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque) -{ - int i, found; - WaitObjects *w = &wait_objects; - - found = 0; - for (i = 0; i < w->num; i++) { - if (w->events[i] == handle) { - found = 1; - } - if (found) { - w->events[i] = w->events[i + 1]; - w->func[i] = w->func[i + 1]; - w->opaque[i] = w->opaque[i + 1]; - w->revents[i] = w->revents[i + 1]; - } - } - if (found) { - w->num--; - } -} - -void qemu_fd_register(int fd) -{ - WSAEventSelect(fd, event_notifier_get_handle(&qemu_aio_context->notifier), - FD_READ | FD_ACCEPT | FD_CLOSE | - FD_CONNECT | FD_WRITE | FD_OOB); -} - -static int pollfds_fill(GArray *pollfds, fd_set *rfds, fd_set *wfds, - fd_set *xfds) -{ - int nfds = -1; - int i; - - for (i = 0; i < pollfds->len; i++) { - GPollFD *pfd = &g_array_index(pollfds, GPollFD, i); - int fd = pfd->fd; - int events = pfd->events; - if (events & G_IO_IN) { - FD_SET(fd, rfds); - nfds = MAX(nfds, fd); - } - if (events & G_IO_OUT) { - FD_SET(fd, wfds); - nfds = MAX(nfds, fd); - } - if (events & G_IO_PRI) { - FD_SET(fd, xfds); - nfds = MAX(nfds, fd); - } - } - return nfds; -} - -static void pollfds_poll(GArray *pollfds, int nfds, fd_set *rfds, - fd_set *wfds, fd_set *xfds) -{ - int i; - - for (i = 0; i < pollfds->len; i++) { - GPollFD *pfd = &g_array_index(pollfds, GPollFD, i); - int fd = pfd->fd; - int revents = 0; - - if (FD_ISSET(fd, rfds)) { - revents |= G_IO_IN; - } - if (FD_ISSET(fd, wfds)) { - revents |= G_IO_OUT; - } - if (FD_ISSET(fd, xfds)) { - revents |= G_IO_PRI; - } - pfd->revents = revents & pfd->events; - } -} - -static int os_host_main_loop_wait(int64_t timeout) -{ - GMainContext *context = g_main_context_default(); - GPollFD poll_fds[1024 * 2]; /* this is probably overkill */ - int select_ret = 0; - int g_poll_ret, ret, i, n_poll_fds; - PollingEntry *pe; - WaitObjects *w = &wait_objects; - gint poll_timeout; - int64_t poll_timeout_ns; - static struct timeval tv0; - fd_set rfds, wfds, xfds; - int nfds; - - /* XXX: need to suppress polling by better using win32 events */ - ret = 0; - for (pe = first_polling_entry; pe != NULL; pe = pe->next) { - ret |= pe->func(pe->opaque); - } - if (ret != 0) { - return ret; - } - - FD_ZERO(&rfds); - FD_ZERO(&wfds); - FD_ZERO(&xfds); - nfds = pollfds_fill(gpollfds, &rfds, &wfds, &xfds); - if (nfds >= 0) { - select_ret = select(nfds + 1, &rfds, &wfds, &xfds, &tv0); - if (select_ret != 0) { - timeout = 0; - } - if (select_ret > 0) { - pollfds_poll(gpollfds, nfds, &rfds, &wfds, &xfds); - } - } - - g_main_context_prepare(context, &max_priority); - n_poll_fds = g_main_context_query(context, max_priority, &poll_timeout, - poll_fds, ARRAY_SIZE(poll_fds)); - g_assert(n_poll_fds <= ARRAY_SIZE(poll_fds)); - - for (i = 0; i < w->num; i++) { - poll_fds[n_poll_fds + i].fd = (DWORD_PTR)w->events[i]; - poll_fds[n_poll_fds + i].events = G_IO_IN; - } - - if (poll_timeout < 0) { - poll_timeout_ns = -1; - } else { - poll_timeout_ns = (int64_t)poll_timeout * (int64_t)SCALE_MS; - } - - poll_timeout_ns = qemu_soonest_timeout(poll_timeout_ns, timeout); - - qemu_mutex_unlock_iothread(); - g_poll_ret = qemu_poll_ns(poll_fds, n_poll_fds + w->num, poll_timeout_ns); - - qemu_mutex_lock_iothread(); - if (g_poll_ret > 0) { - for (i = 0; i < w->num; i++) { - w->revents[i] = poll_fds[n_poll_fds + i].revents; - } - for (i = 0; i < w->num; i++) { - if (w->revents[i] && w->func[i]) { - w->func[i](w->opaque[i]); - } - } - } - - if (g_main_context_check(context, max_priority, poll_fds, n_poll_fds)) { - g_main_context_dispatch(context); - } - - return select_ret || g_poll_ret; -} -#endif - -int main_loop_wait(int nonblocking) -{ - int ret; - uint32_t timeout = UINT32_MAX; - int64_t timeout_ns; - - if (nonblocking) { - timeout = 0; - } - - /* poll any events */ - g_array_set_size(gpollfds, 0); /* reset for new iteration */ - /* XXX: separate device handlers from system ones */ -#ifdef CONFIG_SLIRP - slirp_pollfds_fill(gpollfds, &timeout); -#endif - - if (timeout == UINT32_MAX) { - timeout_ns = -1; - } else { - timeout_ns = (uint64_t)timeout * (int64_t)(SCALE_MS); - } - - timeout_ns = qemu_soonest_timeout(timeout_ns, - timerlistgroup_deadline_ns( - &main_loop_tlg)); - - ret = os_host_main_loop_wait(timeout_ns); -#ifdef CONFIG_SLIRP - slirp_pollfds_poll(gpollfds, (ret < 0)); -#endif - - /* CPU thread can infinitely wait for event after - missing the warp */ - qemu_start_warp_timer(); - qemu_clock_run_all_timers(); - - return ret; -} - -/* Functions to operate on the main QEMU AioContext. */ - -QEMUBH *qemu_bh_new(QEMUBHFunc *cb, void *opaque) -{ - return aio_bh_new(qemu_aio_context, cb, opaque); -} |