x86_64: remove nested irq disables

setup_APIC_timer disables interrupts anyway. So no need to do the same
in setup_boot_APIC_clock and setup_secondary_APIC_clock. Disable
interrupts explicit in the calibration code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>

diff --git a/arch/x86/kernel/apic_64.c b/arch/x86/kernel/apic_64.c
index f74b1c20e5c013f21b9f6685aecad43057a68888..40938ef99dc2dc9956d5bd42827eaecae3edeea7 100644 (file)
--- a/arch/x86/kernel/apic_64.c
+++ b/arch/x86/kernel/apic_64.c
@@ -826,6 +826,9 @@ static void __init calibrate_APIC_clock(void)
        unsigned apic, apic_start;
        unsigned long tsc, tsc_start;
        int result;
+
+       local_irq_disable();
+
        /*
         * Put whatever arbitrary (but long enough) timeout
         * value into the APIC clock, we just want to get the
@@ -855,6 +858,9 @@ static void __init calibrate_APIC_clock(void)
                result = (apic_start - apic) * 1000L * tsc_khz /
                                        (tsc - tsc_start);
        }
+
+       local_irq_enable();
+
        printk(KERN_DEBUG "APIC timer calibration result %d\n", result);
 
        printk(KERN_INFO "Detected %d.%03d MHz APIC timer.\n",
@@ -873,22 +879,16 @@ void __init setup_boot_APIC_clock (void)
        printk(KERN_INFO "Using local APIC timer interrupts.\n");
        using_apic_timer = 1;
 
-       local_irq_disable();
-
        calibrate_APIC_clock();
        /*
         * Now set up the timer for real.
         */
        setup_APIC_timer();
-
-       local_irq_enable();
 }
 
 void __cpuinit setup_secondary_APIC_clock(void)
 {
-       local_irq_disable(); /* FIXME: Do we need this? --RR */
        setup_APIC_timer();
-       local_irq_enable();
 }
 
 void disable_APIC_timer(void)