x86: Print ratio freq_max/freq_base used in frequency invariance calculations
authorGiovanni Gherdovich <ggherdovich@suse.cz>
Thu, 12 Nov 2020 18:26:14 +0000 (19:26 +0100)
committerIngo Molnar <mingo@kernel.org>
Fri, 11 Dec 2020 09:30:23 +0000 (10:30 +0100)
commit3149cd55302748df771dc1c8c10f34b1cbce88ed
tree0267ae86e5e37fe85c50b91e15b3d1efda85c440
parent976df7e5730e3ec8a7e192c09c10ce6e8db07e65
x86: Print ratio freq_max/freq_base used in frequency invariance calculations

The value freq_max/freq_base is a fundamental component of frequency
invariance calculations. It may come from a variety of sources such as MSRs
or ACPI data, tracking it down when troubleshooting a system could be
non-trivial. It is worth saving it in the kernel logs.

 # dmesg | grep 'Estimated ratio of average max'
 [   14.024036] smpboot: Estimated ratio of average max frequency by base frequency (times 1024): 1289

Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20201112182614.10700-4-ggherdovich@suse.cz
arch/x86/kernel/smpboot.c