Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

[powerpc.git] / arch / x86_64 / kernel / smp.c

diff --git a/arch/x86_64/kernel/smp.c b/arch/x86_64/kernel/smp.c
index 4f67697..2ff4685 100644 (file)
--- a/arch/x86_64/kernel/smp.c
+++ b/arch/x86_64/kernel/smp.c
@@ -14,7 +14,6 @@
 #include <linux/mm.h>
 #include <linux/delay.h>
 #include <linux/spinlock.h>
-#include <linux/smp_lock.h>
 #include <linux/smp.h>
 #include <linux/kernel_stat.h>
 #include <linux/mc146818rtc.h>
@@ -376,16 +375,20 @@ int smp_call_function_single (int cpu, void (*func) (void *info), void *info,
        /* prevent preemption and reschedule on another processor */
        int me = get_cpu();
        if (cpu == me) {
-               WARN_ON(1);
                put_cpu();
-               return -EBUSY;
+               return 0;
        }
+
+       /* Can deadlock when called with interrupts disabled */
+       WARN_ON(irqs_disabled());
+
        spin_lock_bh(&call_lock);
        __smp_call_function_single(cpu, func, info, nonatomic, wait);
        spin_unlock_bh(&call_lock);
        put_cpu();
        return 0;
 }
+EXPORT_SYMBOL(smp_call_function_single);
 
 /*
  * this function sends a 'generic call function' IPI to all other CPUs
@@ -448,42 +451,34 @@ int smp_call_function (void (*func) (void *info), void *info, int nonatomic,
 }
 EXPORT_SYMBOL(smp_call_function);
 
-void smp_stop_cpu(void)
+static void stop_this_cpu(void *dummy)
 {
-       unsigned long flags;
+       local_irq_disable();
        /*
         * Remove this CPU:
         */
        cpu_clear(smp_processor_id(), cpu_online_map);
-       local_irq_save(flags);
        disable_local_APIC();
-       local_irq_restore(flags);
-}
-
-static void smp_really_stop_cpu(void *dummy)
-{
-       smp_stop_cpu(); 
        for (;;) 
                halt();
 } 
 
 void smp_send_stop(void)
 {
-       int nolock = 0;
+       int nolock;
+       unsigned long flags;
+
        if (reboot_force)
                return;
+
        /* Don't deadlock on the call lock in panic */
-       if (!spin_trylock(&call_lock)) {
-               /* ignore locking because we have panicked anyways */
-               nolock = 1;
-       }
-       __smp_call_function(smp_really_stop_cpu, NULL, 0, 0);
+       nolock = !spin_trylock(&call_lock);
+       local_irq_save(flags);
+       __smp_call_function(stop_this_cpu, NULL, 0, 0);
        if (!nolock)
                spin_unlock(&call_lock);
-
-       local_irq_disable();
        disable_local_APIC();
-       local_irq_enable();
+       local_irq_restore(flags);
 }
 
 /*