[PATCH 11/16] malloc: allow destroying heaps

[Anatoly Burakov <anatoly.burakov@intel.com>]

Add an API to destroy specified heap.

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
 lib/librte_eal/common/include/rte_malloc.h | 23 +++++++++
 lib/librte_eal/common/malloc_heap.c        | 22 ++++++++
 lib/librte_eal/common/malloc_heap.h        |  3 ++
 lib/librte_eal/common/rte_malloc.c         | 58 ++++++++++++++++++++++
 lib/librte_eal/rte_eal_version.map         |  1 +
 5 files changed, 107 insertions(+)

diff --git a/lib/librte_eal/common/include/rte_malloc.h b/lib/librte_eal/common/include/rte_malloc.h
index 182afab1c..8a8cc1e6d 100644
--- a/lib/librte_eal/common/include/rte_malloc.h
+++ b/lib/librte_eal/common/include/rte_malloc.h
@@ -282,6 +282,29 @@ rte_malloc_get_socket_stats(int socket,
 int __rte_experimental
 rte_malloc_heap_create(const char *heap_name);
 
+/**
+ * Destroys a previously created malloc heap with specified name.
+ *
+ * @note This function will return a failure result if not all memory allocated
+ *   from the heap has been freed back to the heap
+ *
+ * @note This function will return a failure result if not all memory segments
+ *   were removed from the heap prior to its destruction
+ *
+ * @param heap_name
+ *   Name of the heap to create.
+ *
+ * @return
+ *   - 0 on success
+ *   - -1 in case of error, with rte_errno set to one of the following:
+ *     EINVAL - ``heap_name`` was NULL, empty or too long
+ *     ENOENT - heap by the name of ``heap_name`` was not found
+ *     EPERM  - attempting to destroy reserved heap
+ *     EBUSY  - heap still contains data
+ */
+int __rte_experimental
+rte_malloc_heap_destroy(const char *heap_name);
+
 /**
  * Find socket ID corresponding to a named heap.
  *
diff --git a/lib/librte_eal/common/malloc_heap.c b/lib/librte_eal/common/malloc_heap.c
index 2742f7b11..471094cd1 100644
--- a/lib/librte_eal/common/malloc_heap.c
+++ b/lib/librte_eal/common/malloc_heap.c
@@ -1036,6 +1036,28 @@ malloc_heap_create(struct malloc_heap *heap, const char *heap_name)
 	return 0;
 }
 
+int
+malloc_heap_destroy(struct malloc_heap *heap)
+{
+	if (heap->alloc_count != 0) {
+		RTE_LOG(ERR, EAL, "Heap is still in use\n");
+		rte_errno = EBUSY;
+		return -1;
+	}
+	if (heap->first != NULL || heap->last != NULL) {
+		RTE_LOG(ERR, EAL, "Heap still contains memory segments\n");
+		rte_errno = EBUSY;
+		return -1;
+	}
+	if (heap->total_size != 0)
+		RTE_LOG(ERR, EAL, "Total size not zero, heap is likely corrupt\n");
+
+	/* after this, the lock will be dropped */
+	memset(heap, 0, sizeof(*heap));
+
+	return 0;
+}
+
 int
 rte_eal_malloc_heap_init(void)
 {
diff --git a/lib/librte_eal/common/malloc_heap.h b/lib/librte_eal/common/malloc_heap.h
index eebee16dc..75278da3c 100644
--- a/lib/librte_eal/common/malloc_heap.h
+++ b/lib/librte_eal/common/malloc_heap.h
@@ -36,6 +36,9 @@ malloc_heap_alloc_biggest(const char *type, int socket, unsigned int flags,
 int
 malloc_heap_create(struct malloc_heap *heap, const char *heap_name);
 
+int
+malloc_heap_destroy(struct malloc_heap *heap);
+
 int
 malloc_heap_free(struct malloc_elem *elem);
 
diff --git a/lib/librte_eal/common/rte_malloc.c b/lib/librte_eal/common/rte_malloc.c
index ade5af406..d135f9730 100644
--- a/lib/librte_eal/common/rte_malloc.c
+++ b/lib/librte_eal/common/rte_malloc.c
@@ -288,6 +288,21 @@ rte_malloc_virt2iova(const void *addr)
 	return ms->iova + RTE_PTR_DIFF(addr, ms->addr);
 }
 
+static struct malloc_heap *
+find_named_heap(const char *name)
+{
+	struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
+	unsigned int i;
+
+	for (i = 0; i < RTE_MAX_HEAPS; i++) {
+		struct malloc_heap *heap = &mcfg->malloc_heaps[i];
+
+		if (!strncmp(name, heap->name, RTE_HEAP_NAME_MAX_LEN))
+			return heap;
+	}
+	return NULL;
+}
+
 int
 rte_malloc_heap_create(const char *heap_name)
 {
@@ -338,3 +353,46 @@ rte_malloc_heap_create(const char *heap_name)
 
 	return ret;
 }
+
+int
+rte_malloc_heap_destroy(const char *heap_name)
+{
+	struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
+	struct malloc_heap *heap = NULL;
+	int ret;
+
+	if (heap_name == NULL ||
+			strnlen(heap_name, RTE_HEAP_NAME_MAX_LEN) == 0 ||
+			strnlen(heap_name, RTE_HEAP_NAME_MAX_LEN) ==
+				RTE_HEAP_NAME_MAX_LEN) {
+		rte_errno = EINVAL;
+		return -1;
+	}
+	rte_rwlock_write_lock(&mcfg->memory_hotplug_lock);
+
+	/* start from non-socket heaps */
+	heap = find_named_heap(heap_name);
+	if (heap == NULL) {
+		RTE_LOG(ERR, EAL, "Heap %s not found\n", heap_name);
+		rte_errno = ENOENT;
+		ret = -1;
+		goto unlock;
+	}
+	/* we shouldn't be able to destroy internal heaps */
+	if (heap->socket_id < RTE_MAX_NUMA_NODES) {
+		rte_errno = EPERM;
+		ret = -1;
+		goto unlock;
+	}
+	/* sanity checks done, now we can destroy the heap */
+	rte_spinlock_lock(&heap->lock);
+	ret = malloc_heap_destroy(heap);
+
+	/* if we failed, lock is still active */
+	if (ret < 0)
+		rte_spinlock_unlock(&heap->lock);
+unlock:
+	rte_rwlock_write_unlock(&mcfg->memory_hotplug_lock);
+
+	return ret;
+}
diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map
index c93dcf1a3..1d3ca0716 100644
--- a/lib/librte_eal/rte_eal_version.map
+++ b/lib/librte_eal/rte_eal_version.map
@@ -312,6 +312,7 @@ EXPERIMENTAL {
 	rte_log_register_type_and_pick_level;
 	rte_malloc_dump_heaps;
 	rte_malloc_heap_create;
+	rte_malloc_heap_destroy;
 	rte_malloc_heap_get_socket;
 	rte_mem_alloc_validator_register;
 	rte_mem_alloc_validator_unregister;
-- 
2.17.1