Prior to the TSC ADJUST MSR being available, the method to set TSC's in
sync with each other naturally caused a small skew between cpu threads.
This was NOT a firmware bug at the time so introducing a whole avalanche
of alarming warning messages might cause unnecessary concern and customer
complaints. (Example: >3000 msgs in a 32 socket Skylake system.)
Simply report the warning condition, if possible do the necessary fixes,
and move on.
Signed-off-by: Mike Travis <mike.tra...@hpe.com>
Reviewed-by: Dimitri Sivanich <dimitri.sivan...@hpe.com>
Reviewed-by: Russ Anderson <russ.ander...@hpe.com>
Reviewed-by: Peter Zijlstra <pet...@infradead.org>
---
arch/x86/kernel/tsc_sync.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)
--- linux.orig/arch/x86/kernel/tsc_sync.c
+++ linux/arch/x86/kernel/tsc_sync.c
@@ -123,10 +123,9 @@ bool tsc_store_and_check_tsc_adjust(bool
* Compare the boot value and complain if it differs in the
* package.
*/
- if (bootval != ref->bootval) {
- pr_warn(FW_BUG "TSC ADJUST differs: Reference CPU%u: %lld
CPU%u: %lld\n",
- refcpu, ref->bootval, cpu, bootval);
- }
+ if (bootval != ref->bootval)
+ printk_once(FW_BUG "TSC ADJUST differs within socket(s), fixing
all errors\n");
+
/*
* The TSC_ADJUST values in a package must be the same. If the boot
* value on this newly upcoming CPU differs from the adjustment
@@ -134,8 +133,6 @@ bool tsc_store_and_check_tsc_adjust(bool
* adjusted value.
*/
if (bootval != ref->adjusted) {
- pr_warn("TSC ADJUST synchronize: Reference CPU%u: %lld CPU%u:
%lld\n",
- refcpu, ref->adjusted, cpu, bootval);
cur->adjusted = ref->adjusted;
wrmsrl(MSR_IA32_TSC_ADJUST, ref->adjusted);
}
--
