From 14bb4e34860af48ef1ea0f52b11611ce4db987fe Mon Sep 17 00:00:00 2001 From: Len Brown Date: Fri, 17 Jun 2016 01:22:45 -0400 Subject: [PATCH] x86/tsc_msr: Remove debugging messages Debugging messages are not necessary after all of the possible hardware failures that never occur. Instead, this code can simply return 0. This code also doesn't need to print in the success case. tsc_init() already prints the TSC frequency, and apic=debug is available if anybody really is interested in printing the LAPIC frequency. Signed-off-by: Len Brown Reviewed-by: Thomas Gleixner Cc: Linus Torvalds Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/cf03279a125b95dfa9b8d3d5b4a66de09cd04050.1466138954.git.len.brown@intel.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/tsc_msr.c | 19 +++---------------- 1 file changed, 3 insertions(+), 16 deletions(-) diff --git a/arch/x86/kernel/tsc_msr.c b/arch/x86/kernel/tsc_msr.c index 4ec5e560ed73..f7ba44b89cc4 100644 --- a/arch/x86/kernel/tsc_msr.c +++ b/arch/x86/kernel/tsc_msr.c @@ -76,9 +76,10 @@ static int match_cpu(u8 family, u8 model) (freq_desc_tables[cpu_index].freqs[freq_id]) /* - * Do MSR calibration only for known/supported CPUs. + * MSR-based CPU/TSC frequency discovery for certain CPUs. * - * Returns the calibration value or 0 if MSR calibration failed. + * Set global "lapic_timer_frequency" to bus_clock_cycles/jiffy + * Return processor base frequency in KHz, or 0 on failure. */ unsigned long try_msr_calibrate_tsc(void) { @@ -100,31 +101,17 @@ unsigned long try_msr_calibrate_tsc(void) rdmsr(MSR_IA32_PERF_STATUS, lo, hi); ratio = (hi >> 8) & 0x1f; } - pr_info("Maximum core-clock to bus-clock ratio: 0x%x\n", ratio); - - if (!ratio) - goto fail; /* Get FSB FREQ ID */ rdmsr(MSR_FSB_FREQ, lo, hi); freq_id = lo & 0x7; freq = id_to_freq(cpu_index, freq_id); - pr_info("Resolved frequency ID: %u, frequency: %u KHz\n", - freq_id, freq); - if (!freq) - goto fail; /* TSC frequency = maximum resolved freq * maximum resolved bus ratio */ res = freq * ratio; - pr_info("TSC runs at %lu KHz\n", res); #ifdef CONFIG_X86_LOCAL_APIC lapic_timer_frequency = (freq * 1000) / HZ; - pr_info("lapic_timer_frequency = %d\n", lapic_timer_frequency); #endif return res; - -fail: - pr_warn("Fast TSC calibration using MSR failed\n"); - return 0; } -- 2.20.1