return (i << 1) + 2;
}
-static void cpudl_exchange(struct cpudl *cp, int a, int b)
+static void cpudl_heapify_down(struct cpudl *cp, int idx)
{
- int cpu_a = cp->elements[a].cpu, cpu_b = cp->elements[b].cpu;
+ int l, r, largest;
- swap(cp->elements[a].cpu, cp->elements[b].cpu);
- swap(cp->elements[a].dl , cp->elements[b].dl );
+ int orig_cpu = cp->elements[idx].cpu;
+ u64 orig_dl = cp->elements[idx].dl;
- swap(cp->elements[cpu_a].idx, cp->elements[cpu_b].idx);
-}
-
-static void cpudl_heapify(struct cpudl *cp, int idx)
-{
- int l, r, largest;
+ if (left_child(idx) >= cp->size)
+ return;
/* adapted from lib/prio_heap.c */
while(1) {
+ u64 largest_dl;
l = left_child(idx);
r = right_child(idx);
largest = idx;
+ largest_dl = orig_dl;
- if ((l < cp->size) && dl_time_before(cp->elements[idx].dl,
- cp->elements[l].dl))
+ if ((l < cp->size) && dl_time_before(orig_dl,
+ cp->elements[l].dl)) {
largest = l;
- if ((r < cp->size) && dl_time_before(cp->elements[largest].dl,
- cp->elements[r].dl))
+ largest_dl = cp->elements[l].dl;
+ }
+ if ((r < cp->size) && dl_time_before(largest_dl,
+ cp->elements[r].dl))
largest = r;
+
if (largest == idx)
break;
- /* Push idx down the heap one level and bump one up */
- cpudl_exchange(cp, largest, idx);
+ /* pull largest child onto idx */
+ cp->elements[idx].cpu = cp->elements[largest].cpu;
+ cp->elements[idx].dl = cp->elements[largest].dl;
+ cp->elements[cp->elements[idx].cpu].idx = idx;
idx = largest;
}
+ /* actual push down of saved original values orig_* */
+ cp->elements[idx].cpu = orig_cpu;
+ cp->elements[idx].dl = orig_dl;
+ cp->elements[cp->elements[idx].cpu].idx = idx;
}
-static void cpudl_change_key(struct cpudl *cp, int idx, u64 new_dl)
+static void cpudl_heapify_up(struct cpudl *cp, int idx)
{
- WARN_ON(idx == IDX_INVALID || !cpu_present(idx));
+ int p;
- if (dl_time_before(new_dl, cp->elements[idx].dl)) {
- cp->elements[idx].dl = new_dl;
- cpudl_heapify(cp, idx);
- } else {
- cp->elements[idx].dl = new_dl;
- while (idx > 0 && dl_time_before(cp->elements[parent(idx)].dl,
- cp->elements[idx].dl)) {
- cpudl_exchange(cp, idx, parent(idx));
- idx = parent(idx);
- }
- }
+ int orig_cpu = cp->elements[idx].cpu;
+ u64 orig_dl = cp->elements[idx].dl;
+
+ if (idx == 0)
+ return;
+
+ do {
+ p = parent(idx);
+ if (dl_time_before(orig_dl, cp->elements[p].dl))
+ break;
+ /* pull parent onto idx */
+ cp->elements[idx].cpu = cp->elements[p].cpu;
+ cp->elements[idx].dl = cp->elements[p].dl;
+ cp->elements[cp->elements[idx].cpu].idx = idx;
+ idx = p;
+ } while (idx != 0);
+ /* actual push up of saved original values orig_* */
+ cp->elements[idx].cpu = orig_cpu;
+ cp->elements[idx].dl = orig_dl;
+ cp->elements[cp->elements[idx].cpu].idx = idx;
+}
+
+static void cpudl_heapify(struct cpudl *cp, int idx)
+{
+ if (idx > 0 && dl_time_before(cp->elements[parent(idx)].dl,
+ cp->elements[idx].dl))
+ cpudl_heapify_up(cp, idx);
+ else
+ cpudl_heapify_down(cp, idx);
}
static inline int cpudl_maximum(struct cpudl *cp)
}
/*
- * cpudl_set - update the cpudl max-heap
+ * cpudl_clear - remove a cpu from the cpudl max-heap
* @cp: the cpudl max-heap context
* @cpu: the target cpu
- * @dl: the new earliest deadline for this cpu
*
* Notes: assumes cpu_rq(cpu)->lock is locked
*
* Returns: (void)
*/
-void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid)
+void cpudl_clear(struct cpudl *cp, int cpu)
{
int old_idx, new_cpu;
unsigned long flags;
WARN_ON(!cpu_present(cpu));
raw_spin_lock_irqsave(&cp->lock, flags);
+
old_idx = cp->elements[cpu].idx;
- if (!is_valid) {
- /* remove item */
- if (old_idx == IDX_INVALID) {
- /*
- * Nothing to remove if old_idx was invalid.
- * This could happen if a rq_offline_dl is
- * called for a CPU without -dl tasks running.
- */
- goto out;
- }
+ if (old_idx == IDX_INVALID) {
+ /*
+ * Nothing to remove if old_idx was invalid.
+ * This could happen if a rq_offline_dl is
+ * called for a CPU without -dl tasks running.
+ */
+ } else {
new_cpu = cp->elements[cp->size - 1].cpu;
cp->elements[old_idx].dl = cp->elements[cp->size - 1].dl;
cp->elements[old_idx].cpu = new_cpu;
cp->size--;
cp->elements[new_cpu].idx = old_idx;
cp->elements[cpu].idx = IDX_INVALID;
- while (old_idx > 0 && dl_time_before(
- cp->elements[parent(old_idx)].dl,
- cp->elements[old_idx].dl)) {
- cpudl_exchange(cp, old_idx, parent(old_idx));
- old_idx = parent(old_idx);
- }
- cpumask_set_cpu(cpu, cp->free_cpus);
- cpudl_heapify(cp, old_idx);
+ cpudl_heapify(cp, old_idx);
- goto out;
+ cpumask_set_cpu(cpu, cp->free_cpus);
}
+ raw_spin_unlock_irqrestore(&cp->lock, flags);
+}
+
+/*
+ * cpudl_set - update the cpudl max-heap
+ * @cp: the cpudl max-heap context
+ * @cpu: the target cpu
+ * @dl: the new earliest deadline for this cpu
+ *
+ * Notes: assumes cpu_rq(cpu)->lock is locked
+ *
+ * Returns: (void)
+ */
+void cpudl_set(struct cpudl *cp, int cpu, u64 dl)
+{
+ int old_idx;
+ unsigned long flags;
+ WARN_ON(!cpu_present(cpu));
+
+ raw_spin_lock_irqsave(&cp->lock, flags);
+
+ old_idx = cp->elements[cpu].idx;
if (old_idx == IDX_INVALID) {
- cp->size++;
- cp->elements[cp->size - 1].dl = dl;
- cp->elements[cp->size - 1].cpu = cpu;
- cp->elements[cpu].idx = cp->size - 1;
- cpudl_change_key(cp, cp->size - 1, dl);
+ int new_idx = cp->size++;
+ cp->elements[new_idx].dl = dl;
+ cp->elements[new_idx].cpu = cpu;
+ cp->elements[cpu].idx = new_idx;
+ cpudl_heapify_up(cp, new_idx);
cpumask_clear_cpu(cpu, cp->free_cpus);
} else {
- cpudl_change_key(cp, old_idx, dl);
+ cp->elements[old_idx].dl = dl;
+ cpudl_heapify(cp, old_idx);
}
-out:
raw_spin_unlock_irqrestore(&cp->lock, flags);
}
projects / cascardo / linux.git / blobdiff