[PATCH v4 03/10] memarea: support alloc/free/update-refcnt API

[datshan <datshan@qq.com>]

From: Chengwen Feng <fengchengwen@huawei.com>

This patch supports rte_memarea_alloc()/rte_memarea_free()/
rte_memarea_update_refcnt() API.

Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
---
 doc/guides/prog_guide/memarea_lib.rst |  10 ++
 lib/memarea/memarea_private.h         |   3 +
 lib/memarea/rte_memarea.c             | 143 ++++++++++++++++++++++++++
 lib/memarea/rte_memarea.h             |  56 ++++++++++
 lib/memarea/version.map               |   3 +
 5 files changed, 215 insertions(+)

diff --git a/doc/guides/prog_guide/memarea_lib.rst b/doc/guides/prog_guide/memarea_lib.rst
index b96dad15f6..41bc0a90cd 100644
--- a/doc/guides/prog_guide/memarea_lib.rst
+++ b/doc/guides/prog_guide/memarea_lib.rst
@@ -33,6 +33,16 @@ returns the pointer to the created memarea or ``NULL`` if the creation failed.
 
 The ``rte_memarea_destroy()`` function is used to destroy a memarea.
 
+The ``rte_memarea_alloc()`` function is used to alloc one memory object from
+the memarea.
+
+The ``rte_memarea_free()`` function is used to free one memory object which
+allocated by ``rte_memarea_alloc()``.
+
+The ``rte_memarea_update_refcnt()`` function is used to update the memory
+object's reference count, if the count reaches zero, the memory object will
+be freed to memarea.
+
 Reference
 ---------
 
diff --git a/lib/memarea/memarea_private.h b/lib/memarea/memarea_private.h
index c76392d3e6..98406879b9 100644
--- a/lib/memarea/memarea_private.h
+++ b/lib/memarea/memarea_private.h
@@ -25,6 +25,9 @@ struct rte_memarea {
 	void                    *area_addr;
 	struct memarea_elem_list elem_list;
 	struct memarea_elem_list free_list;
+
+	uint64_t alloc_fails;
+	uint64_t refcnt_check_fails;
 } __rte_cache_aligned;
 
 #endif /* MEMAREA_PRIVATE_H */
diff --git a/lib/memarea/rte_memarea.c b/lib/memarea/rte_memarea.c
index 868da7661d..a072f07f20 100644
--- a/lib/memarea/rte_memarea.c
+++ b/lib/memarea/rte_memarea.c
@@ -4,6 +4,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <sys/queue.h>
 
 #include <rte_common.h>
 #include <rte_log.h>
@@ -94,6 +95,8 @@ memarea_alloc_area(const struct rte_memarea_param *init)
 		ptr = memarea_alloc_from_system_api(init->total_sz);
 	else if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR)
 		ptr = init->user_addr;
+	else if (init->source == RTE_MEMAREA_SOURCE_USER_MEMAREA)
+		ptr = rte_memarea_alloc(init->user_memarea, init->total_sz, 0);
 
 	if (ptr == NULL)
 		RTE_LOG(ERR, MEMAREA, "memarea: %s alloc memory area fail!\n", init->name);
@@ -145,6 +148,8 @@ memarea_free_area(struct rte_memarea *ma)
 		rte_free(ma->area_addr);
 	else if (ma->init.source == RTE_MEMAREA_SOURCE_SYSTEM_API)
 		free(ma->area_addr);
+	else if (ma->init.source == RTE_MEMAREA_SOURCE_USER_MEMAREA)
+		rte_memarea_free(ma->init.user_memarea, ma->area_addr);
 }
 
 void
@@ -155,3 +160,141 @@ rte_memarea_destroy(struct rte_memarea *ma)
 	memarea_free_area(ma);
 	rte_free(ma);
 }
+
+static inline void
+memarea_lock(struct rte_memarea *ma)
+{
+	if (ma->init.mt_safe)
+		rte_spinlock_lock(&ma->lock);
+}
+
+static inline void
+memarea_unlock(struct rte_memarea *ma)
+{
+	if (ma->init.mt_safe)
+		rte_spinlock_unlock(&ma->lock);
+}
+
+#define memarea_roundup(val, align) ((((val) + ((align) - 1)) / (align)) * (align))
+
+static inline bool
+memarea_whether_add_node(size_t free_size, size_t need_size)
+{
+	size_t align_size = memarea_roundup(need_size, RTE_CACHE_LINE_SIZE);
+	return free_size > align_size && (free_size - align_size) > sizeof(struct memarea_elem);
+}
+
+static inline void
+memarea_add_node(struct rte_memarea *ma, struct memarea_elem *elem, size_t need_size)
+{
+	size_t align_size = memarea_roundup(need_size, RTE_CACHE_LINE_SIZE);
+	struct memarea_elem *new_elem;
+	new_elem = (struct memarea_elem *)((uintptr_t)elem + sizeof(struct memarea_elem) +
+					   align_size);
+	new_elem->size = elem->size - align_size - sizeof(struct memarea_elem);
+	new_elem->cookie = MEMAREA_FREE_ELEM_COOKIE;
+	new_elem->refcnt = 0;
+	TAILQ_INSERT_AFTER(&ma->elem_list, elem, new_elem, elem_node);
+	TAILQ_INSERT_AFTER(&ma->free_list, elem, new_elem, free_node);
+	elem->size = align_size;
+}
+
+void *
+rte_memarea_alloc(struct rte_memarea *ma, size_t size, uint32_t cookie)
+{
+	struct memarea_elem *elem;
+	void *ptr = NULL;
+
+	if (unlikely(ma == NULL || size == 0))
+		return NULL;
+
+	memarea_lock(ma);
+	TAILQ_FOREACH(elem, &ma->free_list, free_node) {
+		if (elem->size < size)
+			continue;
+		if (memarea_whether_add_node(elem->size, size))
+			memarea_add_node(ma, elem, size);
+		elem->cookie = cookie;
+		elem->refcnt = 1;
+		TAILQ_REMOVE(&ma->free_list, elem, free_node);
+		ptr = (void *)((uintptr_t)elem + sizeof(struct memarea_elem));
+		break;
+	}
+	if (unlikely(ptr == NULL))
+		ma->alloc_fails++;
+	memarea_unlock(ma);
+
+	return ptr;
+}
+
+void
+rte_memarea_free(struct rte_memarea *ma, void *ptr)
+{
+	rte_memarea_update_refcnt(ma, ptr, -1);
+}
+
+static inline void
+memarea_merge_node(struct rte_memarea *ma, struct memarea_elem *curr,
+		   struct memarea_elem *next, bool del_next_from_free,
+		   bool add_curr_to_free)
+{
+	curr->size += next->size + sizeof(struct memarea_elem);
+	next->size = 0;
+	next->cookie = 0;
+	TAILQ_REMOVE(&ma->elem_list, next, elem_node);
+	if (del_next_from_free)
+		TAILQ_REMOVE(&ma->free_list, next, free_node);
+	if (add_curr_to_free) {
+		curr->cookie = MEMAREA_FREE_ELEM_COOKIE;
+		TAILQ_INSERT_TAIL(&ma->free_list, curr, free_node);
+	}
+}
+
+static inline void
+memarea_free_elem(struct rte_memarea *ma, struct memarea_elem *elem)
+{
+	struct memarea_elem *prev, *next;
+	bool merged = false;
+	prev = TAILQ_PREV(elem, memarea_elem_list, elem_node);
+	next = TAILQ_NEXT(elem, elem_node);
+	if (prev != NULL && prev->refcnt == 0) {
+		memarea_merge_node(ma, prev, elem, false, false);
+		elem = prev;
+		merged = true;
+	}
+	if (next != NULL && next->refcnt == 0) {
+		memarea_merge_node(ma, elem, next, true, !merged);
+		merged = true;
+	}
+	if (!merged) {
+		elem->cookie = MEMAREA_FREE_ELEM_COOKIE;
+		TAILQ_INSERT_TAIL(&ma->free_list, elem, free_node);
+	}
+}
+
+void
+rte_memarea_update_refcnt(struct rte_memarea *ma, void *ptr, int16_t value)
+{
+	struct memarea_elem *elem = (struct memarea_elem *)((uintptr_t)ptr -
+							    sizeof(struct memarea_elem));
+
+	if (unlikely(ma == NULL || ptr == NULL))
+		return;
+
+	memarea_lock(ma);
+	if (unlikely(elem->refcnt <= 0 || elem->refcnt + value < 0)) {
+		RTE_LOG(ERR, MEMAREA,
+			"memarea: %s cookie: 0x%x curr refcnt: %d update refcnt: %d check fail!\n",
+			ma->init.name, elem->cookie, elem->refcnt, value);
+		ma->refcnt_check_fails++;
+		if (elem->refcnt > 0)
+			elem->refcnt += value;
+		memarea_unlock(ma);
+		return;
+	}
+
+	elem->refcnt += value;
+	if (elem->refcnt == 0)
+		memarea_free_elem(ma, elem);
+	memarea_unlock(ma);
+}
diff --git a/lib/memarea/rte_memarea.h b/lib/memarea/rte_memarea.h
index 543cda4cac..10e0d6ad5a 100644
--- a/lib/memarea/rte_memarea.h
+++ b/lib/memarea/rte_memarea.h
@@ -138,6 +138,62 @@ struct rte_memarea *rte_memarea_create(const struct rte_memarea_param *init);
 __rte_experimental
 void rte_memarea_destroy(struct rte_memarea *ma);
 
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Allocate memory from memarea.
+ *
+ * Allocate one memory object from the memarea.
+ *
+ * @param ma
+ *   The pointer of memarea.
+ * @param size
+ *   The memory size to be allocated.
+ * @param cookie
+ *   User-provided footprint which could used to debug memory leak.
+ *
+ * @return
+ *   Non-NULL on success. Otherwise NULL is returned.
+ */
+__rte_experimental
+void *rte_memarea_alloc(struct rte_memarea *ma, size_t size, uint32_t cookie);
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Free memory to memarea.
+ *
+ * Free one memory object to the memarea.
+ *
+ * @param ma
+ *   The pointer of memarea.
+ * @param ptr
+ *   The pointer of memory object which need be freed.
+ */
+__rte_experimental
+void rte_memarea_free(struct rte_memarea *ma, void *ptr);
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Update memory's refcnt.
+ *
+ * Update one memory object's refcnt.
+ * When refcnt is updated to be zero, the memory object is freed.
+ *
+ * @param ma
+ *   The pointer of memarea.
+ * @param ptr
+ *   The pointer of memory object which need be updated refcnt.
+ * @param value
+ *   The value which need be updated.
+ */
+__rte_experimental
+void rte_memarea_update_refcnt(struct rte_memarea *ma, void *ptr, int16_t value);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/memarea/version.map b/lib/memarea/version.map
index f36a04d7cf..a0026fc5f9 100644
--- a/lib/memarea/version.map
+++ b/lib/memarea/version.map
@@ -1,8 +1,11 @@
 EXPERIMENTAL {
 	global:
 
+	rte_memarea_alloc;
 	rte_memarea_create;
 	rte_memarea_destroy;
+	rte_memarea_free;
+	rte_memarea_update_refcnt;
 
 	local: *;
 };
-- 
2.34.1