Merge branch 'linux-next' of git://git.infradead.org/ubi-2.6

[pandora-kernel.git] / arch / powerpc / mm / mmu_context_nohash.c

diff --git a/arch/powerpc/mm/mmu_context_nohash.c b/arch/powerpc/mm/mmu_context_nohash.c
index 030d000..8343986 100644 (file)
--- a/arch/powerpc/mm/mmu_context_nohash.c
+++ b/arch/powerpc/mm/mmu_context_nohash.c
@@ -46,7 +46,7 @@ static unsigned int next_context, nr_free_contexts;
 static unsigned long *context_map;
 static unsigned long *stale_map[NR_CPUS];
 static struct mm_struct **context_mm;
-static spinlock_t context_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(context_lock);
 
 #define CTX_MAP_SIZE   \
        (sizeof(unsigned long) * (last_context / BITS_PER_LONG + 1))
@@ -73,7 +73,6 @@ static unsigned int steal_context_smp(unsigned int id)
        struct mm_struct *mm;
        unsigned int cpu, max;
 
- again:
        max = last_context - first_context;
 
        /* Attempt to free next_context first and then loop until we manage */
@@ -108,7 +107,9 @@ static unsigned int steal_context_smp(unsigned int id)
        spin_unlock(&context_lock);
        cpu_relax();
        spin_lock(&context_lock);
-       goto again;
+
+       /* This will cause the caller to try again */
+       return MMU_NO_CONTEXT;
 }
 #endif  /* CONFIG_SMP */
 
@@ -194,6 +195,8 @@ void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next)
                WARN_ON(prev->context.active < 1);
                prev->context.active--;
        }
+
+ again:
 #endif /* CONFIG_SMP */
 
        /* If we already have a valid assigned context, skip all that */
@@ -212,7 +215,8 @@ void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next)
 #ifdef CONFIG_SMP
                if (num_online_cpus() > 1) {
                        id = steal_context_smp(id);
-                       goto stolen;
+                       if (id == MMU_NO_CONTEXT)
+                               goto again;
                }
 #endif /* CONFIG_SMP */
                id = steal_context_up(id);
@@ -272,6 +276,7 @@ int init_new_context(struct task_struct *t, struct mm_struct *mm)
  */
 void destroy_context(struct mm_struct *mm)
 {
+       unsigned long flags;
        unsigned int id;
 
        if (mm->context.id == MMU_NO_CONTEXT)
@@ -279,18 +284,18 @@ void destroy_context(struct mm_struct *mm)
 
        WARN_ON(mm->context.active != 0);
 
-       spin_lock(&context_lock);
+       spin_lock_irqsave(&context_lock, flags);
        id = mm->context.id;
        if (id != MMU_NO_CONTEXT) {
                __clear_bit(id, context_map);
                mm->context.id = MMU_NO_CONTEXT;
 #ifdef DEBUG_MAP_CONSISTENCY
                mm->context.active = 0;
-               context_mm[id] = NULL;
 #endif
+               context_mm[id] = NULL;
                nr_free_contexts++;
        }
-       spin_unlock(&context_lock);
+       spin_unlock_irqrestore(&context_lock, flags);
 }
 
 #ifdef CONFIG_SMP