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[Qemu-devel] [RFC] Use cpu_get_icount as cpu_get_host_ticks fallback
From: |
Christopher Covington |
Subject: |
[Qemu-devel] [RFC] Use cpu_get_icount as cpu_get_host_ticks fallback |
Date: |
Fri, 18 Mar 2016 16:56:39 -0400 |
The previous increment-on-read fallback didn't increment fast
enough for some versions of grub.
https://bugs.launchpad.net/qemu-linaro/+bug/893208
Signed-off-by: Christopher Covington <address@hidden>
---
I unfortunately don't have the opportunity to fully test this right
now, but I'm sending it out nevertheless on the off chance that
someone else might.
---
include/qemu/timer.h | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/include/qemu/timer.h b/include/qemu/timer.h
index d0946cb..60c6dd6 100644
--- a/include/qemu/timer.h
+++ b/include/qemu/timer.h
@@ -998,13 +998,12 @@ static inline int64_t cpu_get_host_ticks(void)
}
#else
-/* The host CPU doesn't have an easily accessible cycle counter.
- Just return a monotonically increasing value. This will be
- totally wrong, but hopefully better than nothing. */
+/* The host CPU doesn't have an easily accessible cycle counter, so just return
+ the instruction count. This may make the CPU look like it has an IPC of
+ exactly 1, but that shouldn't cause any functional problems. */
static inline int64_t cpu_get_host_ticks (void)
{
- static int64_t ticks = 0;
- return ticks++;
+ return cpu_get_icount();
}
#endif
--
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