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authorLen Brown <len.brown@intel.com>2016-06-17 05:22:45 (GMT)
committerIngo Molnar <mingo@kernel.org>2016-07-10 15:00:13 (GMT)
commit14bb4e34860af48ef1ea0f52b11611ce4db987fe (patch)
tree0d40b2413323ee87d883fb961a11926f56283d99
parentba8268330dc18d309a39175ea4d2c5d86c2cef09 (diff)
downloadlinux-14bb4e34860af48ef1ea0f52b11611ce4db987fe.tar.xz
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 <len.brown@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/cf03279a125b95dfa9b8d3d5b4a66de09cd04050.1466138954.git.len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
-rw-r--r--arch/x86/kernel/tsc_msr.c19
1 files changed, 3 insertions, 16 deletions
diff --git a/arch/x86/kernel/tsc_msr.c b/arch/x86/kernel/tsc_msr.c
index 4ec5e56..f7ba44b 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;
}