Hi Vitaly:
Thanks for your review.
On 3/24/2020 11:49 PM, Vitaly Kuznetsov wrote:
Yubo Xie <ltykernel@xxxxxxxxx> writes:
sched clock callback should return time with nano second as unit
but current hv callback returns time with 100ns. Fix it.
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Yubo Xie <yuboxie@xxxxxxxxxxxxx>
Signed-off-by: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>
Fixes: adb87ff4f96c ("clocksource/drivers/hyperv: Allocate Hyper-V TSC page statically")
I don't think this is the right commit to reference,
commit bd00cd52d5be655a2f217e2ed74b91a71cb2b14f
Author: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>
Date: Wed Aug 14 20:32:16 2019 +0800
clocksource/drivers/hyperv: Add Hyper-V specific sched clock function
looks like the one.
Sorry. You are right. Will update in the next version.
---
drivers/clocksource/hyperv_timer.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c
index 9d808d595ca8..662ed978fa24 100644
--- a/drivers/clocksource/hyperv_timer.c
+++ b/drivers/clocksource/hyperv_timer.c
@@ -343,7 +343,8 @@ static u64 notrace read_hv_clock_tsc_cs(struct clocksource *arg)
static u64 read_hv_sched_clock_tsc(void)
{
- return read_hv_clock_tsc() - hv_sched_clock_offset;
+ return (read_hv_clock_tsc() - hv_sched_clock_offset)
+ * (NSEC_PER_SEC / HV_CLOCK_HZ);
}
static void suspend_hv_clock_tsc(struct clocksource *arg)
@@ -398,7 +399,8 @@ static u64 notrace read_hv_clock_msr_cs(struct clocksource *arg)
static u64 read_hv_sched_clock_msr(void)
{
- return read_hv_clock_msr() - hv_sched_clock_offset;
+ return (read_hv_clock_msr() - hv_sched_clock_offset)
+ * (NSEC_PER_SEC / HV_CLOCK_HZ);
}
kvmclock seems to have the same (pre-patch) code ...
kvm sched clock gets time from pvclock_clocksource_read() and
the time unit is nanosecond. So there is such issue in KVM code.
static struct clocksource hyperv_cs_msr = {
