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Subject[PATCH] x86/apic: fix a printk precision vs width issue
Date
when HZ is 1000, host bus clock speed is 99812KHz, apic
shows 99.0812 MHz, since the width is 4 char but the max
remainder is 3 char when HZ is 1000
[ 0.136739] ..... calibration result: 99812
[ 0.136930] ..... host bus clock speed is 99.0812 MHz.

fix it by keeping 3 char width, and using 1000 as divisor
and the result is below:
[ 0.136930] ..... host bus clock speed is 99.812 MHz.

Signed-off-by: Li RongQing <lirongqing@baidu.com>
---
arch/x86/kernel/apic/apic.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 20d9a60..7e3b1bf 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -948,15 +948,15 @@ static int __init calibrate_APIC_clock(void)

if (boot_cpu_has(X86_FEATURE_TSC)) {
apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
- "%ld.%04ld MHz.\n",
- (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ),
- (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ));
+ "%ld.%03ld MHz.\n",
+ ((deltatsc) / LAPIC_CAL_LOOPS) * HZ / 1000 / 1000,
+ ((deltatsc) / LAPIC_CAL_LOOPS) * HZ / 1000 % 1000);
}

apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
- "%u.%04u MHz.\n",
- lapic_timer_period / (1000000 / HZ),
- lapic_timer_period % (1000000 / HZ));
+ "%u.%03u MHz.\n",
+ (lapic_timer_period * HZ / 1000) / 1000,
+ (lapic_timer_period * HZ / 1000) % 1000);

/*
* Do a sanity check on the APIC calibration result
--
2.9.4
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