X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=lib%2Fprio_heap%2Fprio_heap.c;h=ae47ebb8e4ba8f0b378e9a31b71b56ba4e4c207f;hb=94a7d04ee6e0d9464422e3d680860d8a2464e6c1;hp=e660b0cdc9125ccbc9e99bf83267a9e3540b37b1;hpb=162769efd7bca728713c4bf8e609fc408d58f512;p=lttng-modules.git

diff --git a/lib/prio_heap/prio_heap.c b/lib/prio_heap/prio_heap.c
index e660b0cd..ae47ebb8 100644
--- a/lib/prio_heap/prio_heap.c
+++ b/lib/prio_heap/prio_heap.c
@@ -20,30 +20,27 @@
 #include <linux/slab.h>
 #include <linux/prio_heap.h>
 
-/*
- * TODO implement heap_init, heap_free, heap_insert.
- */
+int heap_init(struct ptr_heap *heap, size_t size,
+	       gfp_t gfpmask, int gt(void *a, void *b))
+{
+	WARN_ON_ONCE(size == 0);
+	heap->ptrs = kmalloc(size * sizeof(void *), gfpmask);
+	if (!heap->ptrs)
+		return -ENOMEM;
+	heap->size = 0;
+	heap->max = size;
+	heap->gt = gt;
+	return 0;
+}
 
-static void heapify(struct ptr_heap *heap, int pos)
+void heap_free(struct ptr_heap *heap)
 {
-	void **ptrs = heap->ptrs;
-	void *p = ptrs[pos];
+	kfree(heap->ptrs);
+}
 
-	while (1) {
-		int left = 2 * pos + 1;
-		int right = 2 * pos + 2;
-		int largest = pos;
-		if (left < heap->size && heap->gt(ptrs[left], p))
-			largest = left;
-		if (right < heap->size && heap->gt(ptrs[right], ptrs[largest]))
-			largest = right;
-		if (largest == pos)
-			break;
-		/* Push p down the heap one level and bump one up */
-		ptrs[pos] = ptrs[largest];
-		ptrs[largest] = p;
-		pos = largest;
-	}
+static void heapify(struct ptr_heap *heap, int pos)
+{
+	/* TODO */
 }
 
 void *heap_replace_max(struct ptr_heap *heap, void *p)
@@ -64,6 +61,34 @@ void *heap_replace_max(struct ptr_heap *heap, void *p)
 	return res;
 }
 
+void *heap_insert(struct ptr_heap *heap, void *p)
+{
+	void **ptrs = heap->ptrs;
+	void *tmp = NULL;
+
+	if (heap->size < heap->max) {
+		/* Add the element to the end */
+		heap->ptrs[heap->size++] = p;
+		/* rebalance */
+		heapify(heap, 0);
+		return NULL;
+	}
+
+	/*
+	 * Full. We need to replace the largest (if we are
+	 * smaller or equal to this element).
+	 */
+	if (heap->gt(ptrs[0], p)) {
+		tmp = ptrs[0];
+		ptrs[0] = p;
+		/* rebalance */
+		heapify(heap, 0);
+	} else {
+		tmp = p;
+	}
+	return tmp;
+}
+
 void *heap_remove(struct ptr_heap *heap)
 {
 	void **ptrs = heap->ptrs;