Patchwork [v2,2/3] Correct alarm deadline computation

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Submitter Paolo Bonzini
Date Feb. 3, 2011, 1:49 p.m.
Message ID <1296740941-24296-3-git-send-email-pbonzini@redhat.com>
Download mbox | patch
Permalink /patch/81651/
State New
Headers show

Comments

Paolo Bonzini - Feb. 3, 2011, 1:49 p.m.
When the QEMU_CLOCK_HOST clock was added, computation of its
deadline was added to qemu_next_deadline, which is correct but
incomplete.

I noticed this by reading the very convoluted rules whereby
qemu_next_deadline_dyntick is computed, which miss QEMU_CLOCK_HOST
when use_icount is true.  This patch inlines qemu_next_deadline
into qemu_next_deadline_dyntick, and then corrects the logic to skip
only QEMU_CLOCK_VIRTUAL when use_icount is true.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
---
 qemu-timer.c |   15 +++++++++++----
 1 files changed, 11 insertions(+), 4 deletions(-)

Patch

diff --git a/qemu-timer.c b/qemu-timer.c
index 60283a8..c19d0a2 100644
--- a/qemu-timer.c
+++ b/qemu-timer.c
@@ -724,11 +724,18 @@  static uint64_t qemu_next_deadline_dyntick(void)
     int64_t delta;
     int64_t rtdelta;
 
-    if (use_icount)
+    if (!use_icount && active_timers[QEMU_CLOCK_VIRTUAL]) {
+        delta = active_timers[QEMU_CLOCK_VIRTUAL]->expire_time -
+                     qemu_get_clock(vm_clock);
+    } else {
         delta = INT32_MAX;
-    else
-        delta = qemu_next_deadline();
-
+    }
+    if (active_timers[QEMU_CLOCK_HOST]) {
+        int64_t hdelta = active_timers[QEMU_CLOCK_HOST]->expire_time -
+                 qemu_get_clock_ns(host_clock);
+        if (hdelta < delta)
+            delta = hdelta;
+    }
     if (active_timers[QEMU_CLOCK_REALTIME]) {
         rtdelta = (active_timers[QEMU_CLOCK_REALTIME]->expire_time * 1000000 -
                  qemu_get_clock_ns(rt_clock));