x86: disable preemption in delay_tsc()

[karo-tx-linux.git] / arch / x86 / lib / delay_32.c

diff --git a/arch/x86/lib/delay_32.c b/arch/x86/lib/delay_32.c
index 952e7a89c2ac4f0cc218b310e6a0f84da3845d99..aad9d95469dc68dcb25b9fac93b743d44b7d9038 100644 (file)
--- a/arch/x86/lib/delay_32.c
+++ b/arch/x86/lib/delay_32.c
@@ -12,6 +12,7 @@
 
 #include <linux/module.h>
 #include <linux/sched.h>
+#include <linux/preempt.h>
 #include <linux/delay.h>
 
 #include <asm/processor.h>
@@ -42,11 +43,13 @@ static void delay_tsc(unsigned long loops)
 {
        unsigned long bclock, now;
 
+       preempt_disable();              /* TSC's are per-cpu */
        rdtscl(bclock);
        do {
                rep_nop();
                rdtscl(now);
        } while ((now-bclock) < loops);
+       preempt_enable();
 }
 
 /*