[PATCH] i386: Small cleanup to TLB flush code

- Remove outdated comment
- Use cpu_relax() in a busy loop

Signed-off-by: Andi Kleen <ak@suse.de>

diff --git a/arch/i386/kernel/smp.c b/arch/i386/kernel/smp.c
index ffc4f65..9bd9637 100644 (file)
--- a/arch/i386/kernel/smp.c
+++ b/arch/i386/kernel/smp.c
@@ -375,8 +375,7 @@ static void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm,
        /*
         * i'm not happy about this global shared spinlock in the
         * MM hot path, but we'll see how contended it is.
-        * Temporarily this turns IRQs off, so that lockups are
-        * detected by the NMI watchdog.
+        * AK: x86-64 has a faster method that could be ported.
         */
        spin_lock(&tlbstate_lock);
        
@@ -401,7 +400,7 @@ static void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm,
 
        while (!cpus_empty(flush_cpumask))
                /* nothing. lockup detection does not belong here */
-               mb();
+               cpu_relax();
 
        flush_mm = NULL;
        flush_va = 0;