[PATCH v2 17/38] x86/tsc: WARN if TSC sched_clock save/restore used with PV sched_clock

[Sean Christopherson]

Now that all PV clocksources override the sched_clock save/restore hooks
when overriding sched_clock, WARN if the "default" TSC hooks are invoked
when using a PV sched_clock, e.g. to guard against regressions.

Signed-off-by: Sean Christopherson <sea...@google.com>
---
 arch/x86/kernel/tsc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 472d6c71d3a5..5501d76243c8 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -990,7 +990,7 @@ static unsigned long long cyc2ns_suspend;
 
 void tsc_save_sched_clock_state(void)
 {
-       if (!sched_clock_stable())
+       if (!sched_clock_stable() || WARN_ON_ONCE(!using_native_sched_clock()))
                return;
 
        cyc2ns_suspend = sched_clock();
@@ -1010,7 +1010,7 @@ void tsc_restore_sched_clock_state(void)
        unsigned long flags;
        int cpu;
 
-       if (!sched_clock_stable())
+       if (!sched_clock_stable() || WARN_ON_ONCE(!using_native_sched_clock()))
                return;
 
        local_irq_save(flags);
-- 
2.48.1.711.g2feabab25a-goog