[Qemu-devel] [patch 04/14] qemu: explictly rearm alarm timer on main_loop_wait

[mtosatti@redhat.com]

[-- Attachment #1: move-dyntick-rearm-to-main-loop --]
[-- Type: text/plain, Size: 2363 bytes --]

- lift notification code out of try_to_rearm_timer/host_alarm_handler
- probably going to remove alarm timers via signals sometime soon anyway

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

Index: trunk/vl.c
===================================================================
--- trunk.orig/vl.c
+++ trunk/vl.c
@@ -1346,9 +1346,6 @@ static void host_alarm_handler(int host_
 #ifdef _WIN32
         struct qemu_alarm_win32 *data = ((struct qemu_alarm_timer*)dwUser)->priv;
         SetEvent(data->host_alarm);
-#else
-        static const char byte = 0;
-        write(alarm_timer_wfd, &byte, sizeof(byte));
 #endif
         alarm_timer->flags |= ALARM_FLAG_EXPIRED;
 
@@ -1638,27 +1635,13 @@ static void unix_stop_timer(struct qemu_
 
 #endif /* !defined(_WIN32) */
 
-static void try_to_rearm_timer(void *opaque)
-{
-    struct qemu_alarm_timer *t = opaque;
-#ifndef _WIN32
-    ssize_t len;
 
-    /* Drain the notify pipe */
-    do {
-        char buffer[512];
-        len = read(alarm_timer_rfd, buffer, sizeof(buffer));
-    } while ((len == -1 && errno == EINTR) || len > 0);
-#endif
+#ifdef _WIN32
 
-    if (t->flags & ALARM_FLAG_EXPIRED) {
-        alarm_timer->flags &= ~ALARM_FLAG_EXPIRED;
-        qemu_rearm_alarm_timer(alarm_timer);
-    }
+static void dummy_event_handler(void *opaque)
+{
 }
 
-#ifdef _WIN32
-
 static int win32_start_timer(struct qemu_alarm_timer *t)
 {
     TIMECAPS tc;
@@ -1699,7 +1682,7 @@ static int win32_start_timer(struct qemu
         return -1;
     }
 
-    qemu_add_wait_object(data->host_alarm, try_to_rearm_timer, t);
+    qemu_add_wait_object(data->host_alarm, dummy_event_handler, t);
 
     return 0;
 }
@@ -1782,11 +1765,6 @@ static int init_timer_alarm(void)
         goto fail;
     }
 
-#ifndef _WIN32
-    qemu_set_fd_handler2(alarm_timer_rfd, NULL,
-                         try_to_rearm_timer, NULL, t);
-#endif
-
     alarm_timer = t;
 
     return 0;
@@ -3778,6 +3756,12 @@ void main_loop_wait(int timeout)
     }
 #endif
 
+    /* rearm timer, if not periodic */
+    if (alarm_timer->flags & ALARM_FLAG_EXPIRED) {
+        alarm_timer->flags &= ~ALARM_FLAG_EXPIRED;
+        qemu_rearm_alarm_timer(alarm_timer);
+    }
+
     /* vm time timers */
     if (vm_running && likely(!(cur_cpu->singlestep_enabled & SSTEP_NOTIMER)))
         qemu_run_timers(&active_timers[QEMU_TIMER_VIRTUAL],

--