[Qemu-devel] [RFC PATCH v3 36/49] pl031: vmstate in replay mode

[Pavel Dovgalyuk]

This patch modifies vmstate for PL031 RTC. It removes querying of the rtc
and virtual clocks while saving and restoring VM state, because in replay
mode these clocks are stopped while saving. And reading the clock while
restoring the VM state may lead to read of the incorrect values, because
clocks cache in replay module could not be loaded yet.

Signed-off-by: Pavel Dovgalyuk <address@hidden>
---
 hw/timer/pl031.c |   25 ++++++++++++++++++-------
 1 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/hw/timer/pl031.c b/hw/timer/pl031.c
index 40e1700..600fa49 100644
--- a/hw/timer/pl031.c
+++ b/hw/timer/pl031.c
@@ -220,19 +220,30 @@ static void pl031_pre_save(void *opaque)
 {
     PL031State *s = opaque;
 
-    /* tick_offset is base_time - rtc_clock base time.  Instead, we want to
-     * store the base time relative to the QEMU_CLOCK_VIRTUAL for 
backwards-compatibility.  */
-    int64_t delta = qemu_clock_get_ns(rtc_clock) - 
qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
-    s->tick_offset_vmstate = s->tick_offset + delta / get_ticks_per_sec();
+    if (replay_mode == REPLAY_MODE_NONE) {
+        /* tick_offset is base_time - rtc_clock base time.  Instead, we want to
+         * store the base time relative to the QEMU_CLOCK_VIRTUAL
+         * for backwards-compatibility. */
+        int64_t delta = qemu_clock_get_ns(rtc_clock)
+                        - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+        s->tick_offset_vmstate = s->tick_offset + delta / get_ticks_per_sec();
+    } else {
+        s->tick_offset_vmstate = s->tick_offset;
+    }
 }
 
 static int pl031_post_load(void *opaque, int version_id)
 {
     PL031State *s = opaque;
 
-    int64_t delta = qemu_clock_get_ns(rtc_clock) - 
qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
-    s->tick_offset = s->tick_offset_vmstate - delta / get_ticks_per_sec();
-    pl031_set_alarm(s);
+    if (replay_mode == REPLAY_MODE_NONE) {
+        int64_t delta = qemu_clock_get_ns(rtc_clock)
+                        - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+        s->tick_offset = s->tick_offset_vmstate - delta / get_ticks_per_sec();
+        pl031_set_alarm(s);
+    } else {
+        s->tick_offset = s->tick_offset_vmstate;
+    }
     return 0;
 }