Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[linux-2.6-microblaze.git] / kernel / irq / matrix.c

diff --git a/kernel/irq/matrix.c b/kernel/irq/matrix.c
index 5092494..6e6d467 100644 (file)
--- a/kernel/irq/matrix.c
+++ b/kernel/irq/matrix.c
@@ -124,6 +124,27 @@ static unsigned int matrix_alloc_area(struct irq_matrix *m, struct cpumap *cm,
        return area;
 }
 
+/* Find the best CPU which has the lowest vector allocation count */
+static unsigned int matrix_find_best_cpu(struct irq_matrix *m,
+                                       const struct cpumask *msk)
+{
+       unsigned int cpu, best_cpu, maxavl = 0;
+       struct cpumap *cm;
+
+       best_cpu = UINT_MAX;
+
+       for_each_cpu(cpu, msk) {
+               cm = per_cpu_ptr(m->maps, cpu);
+
+               if (!cm->online || cm->available <= maxavl)
+                       continue;
+
+               best_cpu = cpu;
+               maxavl = cm->available;
+       }
+       return best_cpu;
+}
+
 /**
  * irq_matrix_assign_system - Assign system wide entry in the matrix
  * @m:         Matrix pointer
@@ -239,11 +260,21 @@ void irq_matrix_remove_managed(struct irq_matrix *m, const struct cpumask *msk)
  * @m:         Matrix pointer
  * @cpu:       On which CPU the interrupt should be allocated
  */
-int irq_matrix_alloc_managed(struct irq_matrix *m, unsigned int cpu)
+int irq_matrix_alloc_managed(struct irq_matrix *m, const struct cpumask *msk,
+                            unsigned int *mapped_cpu)
 {
-       struct cpumap *cm = per_cpu_ptr(m->maps, cpu);
-       unsigned int bit, end = m->alloc_end;
+       unsigned int bit, cpu, end = m->alloc_end;
+       struct cpumap *cm;
+
+       if (cpumask_empty(msk))
+               return -EINVAL;
+
+       cpu = matrix_find_best_cpu(m, msk);
+       if (cpu == UINT_MAX)
+               return -ENOSPC;
 
+       cm = per_cpu_ptr(m->maps, cpu);
+       end = m->alloc_end;
        /* Get managed bit which are not allocated */
        bitmap_andnot(m->scratch_map, cm->managed_map, cm->alloc_map, end);
        bit = find_first_bit(m->scratch_map, end);
@@ -252,6 +283,7 @@ int irq_matrix_alloc_managed(struct irq_matrix *m, unsigned int cpu)
        set_bit(bit, cm->alloc_map);
        cm->allocated++;
        m->total_allocated++;
+       *mapped_cpu = cpu;
        trace_irq_matrix_alloc_managed(bit, cpu, m, cm);
        return bit;
 }
@@ -322,37 +354,27 @@ void irq_matrix_remove_reserved(struct irq_matrix *m)
 int irq_matrix_alloc(struct irq_matrix *m, const struct cpumask *msk,
                     bool reserved, unsigned int *mapped_cpu)
 {
-       unsigned int cpu, best_cpu, maxavl = 0;
+       unsigned int cpu, bit;
        struct cpumap *cm;
-       unsigned int bit;
-
-       best_cpu = UINT_MAX;
-       for_each_cpu(cpu, msk) {
-               cm = per_cpu_ptr(m->maps, cpu);
 
-               if (!cm->online || cm->available <= maxavl)
-                       continue;
+       cpu = matrix_find_best_cpu(m, msk);
+       if (cpu == UINT_MAX)
+               return -ENOSPC;
 
-               best_cpu = cpu;
-               maxavl = cm->available;
-       }
+       cm = per_cpu_ptr(m->maps, cpu);
+       bit = matrix_alloc_area(m, cm, 1, false);
+       if (bit >= m->alloc_end)
+               return -ENOSPC;
+       cm->allocated++;
+       cm->available--;
+       m->total_allocated++;
+       m->global_available--;
+       if (reserved)
+               m->global_reserved--;
+       *mapped_cpu = cpu;
+       trace_irq_matrix_alloc(bit, cpu, m, cm);
+       return bit;
 
-       if (maxavl) {
-               cm = per_cpu_ptr(m->maps, best_cpu);
-               bit = matrix_alloc_area(m, cm, 1, false);
-               if (bit < m->alloc_end) {
-                       cm->allocated++;
-                       cm->available--;
-                       m->total_allocated++;
-                       m->global_available--;
-                       if (reserved)
-                               m->global_reserved--;
-                       *mapped_cpu = best_cpu;
-                       trace_irq_matrix_alloc(bit, best_cpu, m, cm);
-                       return bit;
-               }
-       }
-       return -ENOSPC;
 }
 
 /**