mmc: s3c6410: enable ADMA feature in 6410 sdhci controller

[safe/jmp/linux-2.6] / kernel / sched_cpupri.c

diff --git a/kernel/sched_cpupri.c b/kernel/sched_cpupri.c
index e6c2517..e6871cb 100644 (file)
--- a/kernel/sched_cpupri.c
+++ b/kernel/sched_cpupri.c
@@ -27,6 +27,7 @@
  *  of the License.
  */
 
+#include <linux/gfp.h>
 #include "sched_cpupri.h"
 
 /* Convert between a 140 based task->prio, and our 102 based cpupri */
@@ -47,9 +48,7 @@ static int convert_prio(int prio)
 }
 
 #define for_each_cpupri_active(array, idx)                    \
-  for (idx = find_first_bit(array, CPUPRI_NR_PRIORITIES);     \
-       idx < CPUPRI_NR_PRIORITIES;                            \
-       idx = find_next_bit(array, CPUPRI_NR_PRIORITIES, idx+1))
+       for_each_set_bit(idx, array, CPUPRI_NR_PRIORITIES)
 
 /**
  * cpupri_find - find the best (lowest-pri) CPU in the system
@@ -58,7 +57,7 @@ static int convert_prio(int prio)
  * @lowest_mask: A mask to fill in with selected CPUs (or NULL)
  *
  * Note: This function returns the recommended CPUs as calculated during the
- * current invokation.  By the time the call returns, the CPUs may have in
+ * current invocation.  By the time the call returns, the CPUs may have in
  * fact changed priorities any number of times.  While not ideal, it is not
  * an issue of correctness since the normal rebalancer logic will correct
  * any discrepancies created by racing against the uncertainty of the current
@@ -81,8 +80,21 @@ int cpupri_find(struct cpupri *cp, struct task_struct *p,
                if (cpumask_any_and(&p->cpus_allowed, vec->mask) >= nr_cpu_ids)
                        continue;
 
-               if (lowest_mask)
+               if (lowest_mask) {
                        cpumask_and(lowest_mask, &p->cpus_allowed, vec->mask);
+
+                       /*
+                        * We have to ensure that we have at least one bit
+                        * still set in the array, since the map could have
+                        * been concurrently emptied between the first and
+                        * second reads of vec->mask.  If we hit this
+                        * condition, simply act as though we never hit this
+                        * priority level and continue on.
+                        */
+                       if (cpumask_any(lowest_mask) >= nr_cpu_ids)
+                               continue;
+               }
+
                return 1;
        }
 
@@ -114,32 +126,34 @@ void cpupri_set(struct cpupri *cp, int cpu, int newpri)
 
        /*
         * If the cpu was currently mapped to a different value, we
-        * first need to unmap the old value
+        * need to map it to the new value then remove the old value.
+        * Note, we must add the new value first, otherwise we risk the
+        * cpu being cleared from pri_active, and this cpu could be
+        * missed for a push or pull.
         */
-       if (likely(oldpri != CPUPRI_INVALID)) {
-               struct cpupri_vec *vec  = &cp->pri_to_cpu[oldpri];
-
-               spin_lock_irqsave(&vec->lock, flags);
-
-               vec->count--;
-               if (!vec->count)
-                       clear_bit(oldpri, cp->pri_active);
-               cpumask_clear_cpu(cpu, vec->mask);
-
-               spin_unlock_irqrestore(&vec->lock, flags);
-       }
-
        if (likely(newpri != CPUPRI_INVALID)) {
                struct cpupri_vec *vec = &cp->pri_to_cpu[newpri];
 
-               spin_lock_irqsave(&vec->lock, flags);
+               raw_spin_lock_irqsave(&vec->lock, flags);
 
                cpumask_set_cpu(cpu, vec->mask);
                vec->count++;
                if (vec->count == 1)
                        set_bit(newpri, cp->pri_active);
 
-               spin_unlock_irqrestore(&vec->lock, flags);
+               raw_spin_unlock_irqrestore(&vec->lock, flags);
+       }
+       if (likely(oldpri != CPUPRI_INVALID)) {
+               struct cpupri_vec *vec  = &cp->pri_to_cpu[oldpri];
+
+               raw_spin_lock_irqsave(&vec->lock, flags);
+
+               vec->count--;
+               if (!vec->count)
+                       clear_bit(oldpri, cp->pri_active);
+               cpumask_clear_cpu(cpu, vec->mask);
+
+               raw_spin_unlock_irqrestore(&vec->lock, flags);
        }
 
        *currpri = newpri;
@@ -165,7 +179,7 @@ int cpupri_init(struct cpupri *cp, bool bootmem)
        for (i = 0; i < CPUPRI_NR_PRIORITIES; i++) {
                struct cpupri_vec *vec = &cp->pri_to_cpu[i];
 
-               spin_lock_init(&vec->lock);
+               raw_spin_lock_init(&vec->lock);
                vec->count = 0;
                if (!zalloc_cpumask_var(&vec->mask, gfp))
                        goto cleanup;