]> git.proxmox.com Git - mirror_qemu.git/blobdiff - qemu-timer.c
virtio-scsi: Don't abort when media is ejected
[mirror_qemu.git] / qemu-timer.c
index 6b62e88669e54f2bbcb969fee2a3445fabb0ff7b..9299cdc5fb72df6f4ff5e85cd437acb4f7bb2ba6 100644 (file)
  * THE SOFTWARE.
  */
 
+#include "qemu/osdep.h"
+#include "qemu/main-loop.h"
+#include "qemu/timer.h"
+#include "sysemu/replay.h"
 #include "sysemu/sysemu.h"
-#include "monitor/monitor.h"
-#include "ui/console.h"
-
-#include "hw/hw.h"
 
-#include "qemu/timer.h"
 #ifdef CONFIG_POSIX
 #include <pthread.h>
 #endif
@@ -45,6 +44,7 @@
 /* timers */
 
 typedef struct QEMUClock {
+    /* We rely on BQL to protect the timerlists */
     QLIST_HEAD(, QEMUTimerList) timerlists;
 
     NotifierList reset_notifiers;
@@ -55,7 +55,7 @@ typedef struct QEMUClock {
 } QEMUClock;
 
 QEMUTimerListGroup main_loop_tlg;
-QEMUClock qemu_clocks[QEMU_CLOCK_MAX];
+static QEMUClock qemu_clocks[QEMU_CLOCK_MAX];
 
 /* A QEMUTimerList is a list of timers attached to a clock. More
  * than one QEMUTimerList can be attached to each clock, for instance
@@ -71,6 +71,9 @@ struct QEMUTimerList {
     QLIST_ENTRY(QEMUTimerList) list;
     QEMUTimerListNotifyCB *notify_cb;
     void *notify_opaque;
+
+    /* lightweight method to mark the end of timerlist's running */
+    QemuEvent timers_done_ev;
 };
 
 /**
@@ -99,6 +102,7 @@ QEMUTimerList *timerlist_new(QEMUClockType type,
     QEMUClock *clock = qemu_clock_ptr(type);
 
     timer_list = g_malloc0(sizeof(QEMUTimerList));
+    qemu_event_init(&timer_list->timers_done_ev, true);
     timer_list->clock = clock;
     timer_list->notify_cb = cb;
     timer_list->notify_opaque = opaque;
@@ -121,8 +125,11 @@ static void qemu_clock_init(QEMUClockType type)
 {
     QEMUClock *clock = qemu_clock_ptr(type);
 
+    /* Assert that the clock of type TYPE has not been initialized yet. */
+    assert(main_loop_tlg.tl[type] == NULL);
+
     clock->type = type;
-    clock->enabled = true;
+    clock->enabled = (type == QEMU_CLOCK_VIRTUAL ? false : true);
     clock->last = INT64_MIN;
     QLIST_INIT(&clock->timerlists);
     notifier_list_init(&clock->reset_notifiers);
@@ -143,13 +150,25 @@ void qemu_clock_notify(QEMUClockType type)
     }
 }
 
+/* Disabling the clock will wait for related timerlists to stop
+ * executing qemu_run_timers.  Thus, this functions should not
+ * be used from the callback of a timer that is based on @clock.
+ * Doing so would cause a deadlock.
+ *
+ * Caller should hold BQL.
+ */
 void qemu_clock_enable(QEMUClockType type, bool enabled)
 {
     QEMUClock *clock = qemu_clock_ptr(type);
+    QEMUTimerList *tl;
     bool old = clock->enabled;
     clock->enabled = enabled;
     if (enabled && !old) {
         qemu_clock_notify(type);
+    } else if (!enabled && old) {
+        QLIST_FOREACH(tl, &clock->timerlists, list) {
+            qemu_event_wait(&tl->timers_done_ev);
+        }
     }
 }
 
@@ -273,7 +292,7 @@ int qemu_timeout_ns_to_ms(int64_t ns)
     /* Always round up, because it's better to wait too long than to wait too
      * little and effectively busy-wait
      */
-    ms = (ns + SCALE_MS - 1) / SCALE_MS;
+    ms = DIV_ROUND_UP(ns, SCALE_MS);
 
     /* To avoid overflow problems, limit this to 2^31, i.e. approx 25 days */
     if (ms > (int64_t) INT32_MAX) {
@@ -294,7 +313,14 @@ int qemu_poll_ns(GPollFD *fds, guint nfds, int64_t timeout)
         return ppoll((struct pollfd *)fds, nfds, NULL, NULL);
     } else {
         struct timespec ts;
-        ts.tv_sec = timeout / 1000000000LL;
+        int64_t tvsec = timeout / 1000000000LL;
+        /* Avoid possibly overflowing and specifying a negative number of
+         * seconds, which would turn a very long timeout into a busy-wait.
+         */
+        if (tvsec > (int64_t)INT32_MAX) {
+            tvsec = INT32_MAX;
+        }
+        ts.tv_sec = tvsec;
         ts.tv_nsec = timeout % 1000000000LL;
         return ppoll((struct pollfd *)fds, nfds, &ts, NULL);
     }
@@ -304,9 +330,9 @@ int qemu_poll_ns(GPollFD *fds, guint nfds, int64_t timeout)
 }
 
 
-void timer_init(QEMUTimer *ts,
-                QEMUTimerList *timer_list, int scale,
-                QEMUTimerCB *cb, void *opaque)
+void timer_init_tl(QEMUTimer *ts,
+                   QEMUTimerList *timer_list, int scale,
+                   QEMUTimerCB *cb, void *opaque)
 {
     ts->timer_list = timer_list;
     ts->cb = cb;
@@ -315,6 +341,12 @@ void timer_init(QEMUTimer *ts,
     ts->expire_time = -1;
 }
 
+void timer_deinit(QEMUTimer *ts)
+{
+    assert(ts->expire_time == -1);
+    ts->timer_list = NULL;
+}
+
 void timer_free(QEMUTimer *ts)
 {
     g_free(ts);
@@ -338,14 +370,46 @@ static void timer_del_locked(QEMUTimerList *timer_list, QEMUTimer *ts)
     }
 }
 
+static bool timer_mod_ns_locked(QEMUTimerList *timer_list,
+                                QEMUTimer *ts, int64_t expire_time)
+{
+    QEMUTimer **pt, *t;
+
+    /* add the timer in the sorted list */
+    pt = &timer_list->active_timers;
+    for (;;) {
+        t = *pt;
+        if (!timer_expired_ns(t, expire_time)) {
+            break;
+        }
+        pt = &t->next;
+    }
+    ts->expire_time = MAX(expire_time, 0);
+    ts->next = *pt;
+    *pt = ts;
+
+    return pt == &timer_list->active_timers;
+}
+
+static void timerlist_rearm(QEMUTimerList *timer_list)
+{
+    /* Interrupt execution to force deadline recalculation.  */
+    if (timer_list->clock->type == QEMU_CLOCK_VIRTUAL) {
+        qemu_start_warp_timer();
+    }
+    timerlist_notify(timer_list);
+}
+
 /* stop a timer, but do not dealloc it */
 void timer_del(QEMUTimer *ts)
 {
     QEMUTimerList *timer_list = ts->timer_list;
 
-    qemu_mutex_lock(&timer_list->active_timers_lock);
-    timer_del_locked(timer_list, ts);
-    qemu_mutex_unlock(&timer_list->active_timers_lock);
+    if (timer_list) {
+        qemu_mutex_lock(&timer_list->active_timers_lock);
+        timer_del_locked(timer_list, ts);
+        qemu_mutex_unlock(&timer_list->active_timers_lock);
+    }
 }
 
 /* modify the current timer so that it will be fired when current_time
@@ -353,30 +417,39 @@ void timer_del(QEMUTimer *ts)
 void timer_mod_ns(QEMUTimer *ts, int64_t expire_time)
 {
     QEMUTimerList *timer_list = ts->timer_list;
-    QEMUTimer **pt, *t;
+    bool rearm;
 
     qemu_mutex_lock(&timer_list->active_timers_lock);
     timer_del_locked(timer_list, ts);
+    rearm = timer_mod_ns_locked(timer_list, ts, expire_time);
+    qemu_mutex_unlock(&timer_list->active_timers_lock);
 
-    /* add the timer in the sorted list */
-    pt = &timer_list->active_timers;
-    for(;;) {
-        t = *pt;
-        if (!timer_expired_ns(t, expire_time)) {
-            break;
+    if (rearm) {
+        timerlist_rearm(timer_list);
+    }
+}
+
+/* modify the current timer so that it will be fired when current_time
+   >= expire_time or the current deadline, whichever comes earlier.
+   The corresponding callback will be called. */
+void timer_mod_anticipate_ns(QEMUTimer *ts, int64_t expire_time)
+{
+    QEMUTimerList *timer_list = ts->timer_list;
+    bool rearm;
+
+    qemu_mutex_lock(&timer_list->active_timers_lock);
+    if (ts->expire_time == -1 || ts->expire_time > expire_time) {
+        if (ts->expire_time != -1) {
+            timer_del_locked(timer_list, ts);
         }
-        pt = &t->next;
+        rearm = timer_mod_ns_locked(timer_list, ts, expire_time);
+    } else {
+        rearm = false;
     }
-    ts->expire_time = MAX(expire_time, 0);
-    ts->next = *pt;
-    *pt = ts;
     qemu_mutex_unlock(&timer_list->active_timers_lock);
 
-    /* Rearm if necessary  */
-    if (pt == &timer_list->active_timers) {
-        /* Interrupt execution to force deadline recalculation.  */
-        qemu_clock_warp(timer_list->clock->type);
-        timerlist_notify(timer_list);
+    if (rearm) {
+        timerlist_rearm(timer_list);
     }
 }
 
@@ -385,6 +458,11 @@ void timer_mod(QEMUTimer *ts, int64_t expire_time)
     timer_mod_ns(ts, expire_time * ts->scale);
 }
 
+void timer_mod_anticipate(QEMUTimer *ts, int64_t expire_time)
+{
+    timer_mod_anticipate_ns(ts, expire_time * ts->scale);
+}
+
 bool timer_pending(QEMUTimer *ts)
 {
     return ts->expire_time >= 0;
@@ -403,8 +481,30 @@ bool timerlist_run_timers(QEMUTimerList *timer_list)
     QEMUTimerCB *cb;
     void *opaque;
 
-    if (!timer_list->clock->enabled) {
-        return progress;
+    qemu_event_reset(&timer_list->timers_done_ev);
+    if (!timer_list->clock->enabled || !timer_list->active_timers) {
+        goto out;
+    }
+
+    switch (timer_list->clock->type) {
+    case QEMU_CLOCK_REALTIME:
+        break;
+    default:
+    case QEMU_CLOCK_VIRTUAL:
+        if (!replay_checkpoint(CHECKPOINT_CLOCK_VIRTUAL)) {
+            goto out;
+        }
+        break;
+    case QEMU_CLOCK_HOST:
+        if (!replay_checkpoint(CHECKPOINT_CLOCK_HOST)) {
+            goto out;
+        }
+        break;
+    case QEMU_CLOCK_VIRTUAL_RT:
+        if (!replay_checkpoint(CHECKPOINT_CLOCK_VIRTUAL_RT)) {
+            goto out;
+        }
+        break;
     }
 
     current_time = qemu_clock_get_ns(timer_list->clock->type);
@@ -428,6 +528,9 @@ bool timerlist_run_timers(QEMUTimerList *timer_list)
         cb(opaque);
         progress = true;
     }
+
+out:
+    qemu_event_set(&timer_list->timers_done_ev);
     return progress;
 }
 
@@ -467,11 +570,17 @@ int64_t timerlistgroup_deadline_ns(QEMUTimerListGroup *tlg)
 {
     int64_t deadline = -1;
     QEMUClockType type;
+    bool play = replay_mode == REPLAY_MODE_PLAY;
     for (type = 0; type < QEMU_CLOCK_MAX; type++) {
-        if (qemu_clock_use_for_deadline(tlg->tl[type]->clock->type)) {
-            deadline = qemu_soonest_timeout(deadline,
-                                            timerlist_deadline_ns(
-                                                tlg->tl[type]));
+        if (qemu_clock_use_for_deadline(type)) {
+            if (!play || type == QEMU_CLOCK_REALTIME) {
+                deadline = qemu_soonest_timeout(deadline,
+                                                timerlist_deadline_ns(tlg->tl[type]));
+            } else {
+                /* Read clock from the replay file and
+                   do not calculate the deadline, based on virtual clock. */
+                qemu_clock_get_ns(type);
+            }
         }
     }
     return deadline;
@@ -493,13 +602,15 @@ int64_t qemu_clock_get_ns(QEMUClockType type)
             return cpu_get_clock();
         }
     case QEMU_CLOCK_HOST:
-        now = get_clock_realtime();
+        now = REPLAY_CLOCK(REPLAY_CLOCK_HOST, get_clock_realtime());
         last = clock->last;
         clock->last = now;
-        if (now < last) {
+        if (now < last || now > (last + get_max_clock_jump())) {
             notifier_list_notify(&clock->reset_notifiers, &now);
         }
         return now;
+    case QEMU_CLOCK_VIRTUAL_RT:
+        return REPLAY_CLOCK(REPLAY_CLOCK_VIRTUAL_RT, cpu_get_clock());
     }
 }