This is a mempool handler that is useful for pipelining apps, where
the mempool cache doesn't really work - example, where we have one
core doing rx (and alloc), and another core doing Tx (and return). In
such a case, the mempool ring simply cycles through all the mbufs,
resulting in a LLC miss on every mbuf allocated when the number of
mbufs is large. A stack recycles buffers more effectively in this
case.
Signed-off-by: David Hunt
---
lib/librte_mempool/Makefile| 1 +
lib/librte_mempool/rte_mempool_stack.c | 154 +
2 files changed, 155 insertions(+)
create mode 100644 lib/librte_mempool/rte_mempool_stack.c
diff --git a/lib/librte_mempool/Makefile b/lib/librte_mempool/Makefile
index f19366e..5aa9ef8 100644
--- a/lib/librte_mempool/Makefile
+++ b/lib/librte_mempool/Makefile
@@ -44,6 +44,7 @@ LIBABIVER := 2
SRCS-$(CONFIG_RTE_LIBRTE_MEMPOOL) += rte_mempool.c
SRCS-$(CONFIG_RTE_LIBRTE_MEMPOOL) += rte_mempool_handler.c
SRCS-$(CONFIG_RTE_LIBRTE_MEMPOOL) += rte_mempool_default.c
+SRCS-$(CONFIG_RTE_LIBRTE_MEMPOOL) += rte_mempool_stack.c
# install includes
SYMLINK-$(CONFIG_RTE_LIBRTE_MEMPOOL)-include := rte_mempool.h
diff --git a/lib/librte_mempool/rte_mempool_stack.c
b/lib/librte_mempool/rte_mempool_stack.c
new file mode 100644
index 000..1874781
--- /dev/null
+++ b/lib/librte_mempool/rte_mempool_stack.c
@@ -0,0 +1,154 @@
+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include
+#include
+#include
+#include
+
+struct rte_mempool_common_stack
+{
+ /* Spinlock to protect access */
+ rte_spinlock_t sl;
+
+ uint32_t size;
+ uint32_t len;
+ void *objs[];
+
+#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
+#endif
+};
+
+static void *
+common_stack_alloc(struct rte_mempool *mp)
+{
+ struct rte_mempool_common_stack *s;
+ char stack_name[RTE_RING_NAMESIZE];
+ unsigned n = mp->size;
+ int size = sizeof(*s) + (n+16)*sizeof(void*);
+
+ /* Allocate our local memory structure */
+ snprintf(stack_name, sizeof(stack_name), "%s-common-stack", mp->name);
+ s = rte_zmalloc_socket(stack_name,
+ size,
+ RTE_CACHE_LINE_SIZE,
+ mp->socket_id);
+ if (s == NULL) {
+ RTE_LOG(ERR, MEMPOOL, "Cannot allocate stack!\n");
+ return NULL;
+ }
+
+ /* And the spinlock we use to protect access */
+ rte_spinlock_init(>sl);
+
+ s->size = n;
+ mp->pool = (void *) s;
+ rte_mempool_set_handler(mp, "stack");
+
+ return (void *) s;
+}
+
+static int common_stack_put(void *p, void * const *obj_table,
+ unsigned n)
+{
+ struct rte_mempool_common_stack * s = (struct rte_mempool_common_stack
*)p;
+ void **cache_objs;
+ unsigned index;
+
+ /* Acquire lock */
+ rte_spinlock_lock(>sl);
+ cache_objs = >objs[s->len];
+
+ /* Is there sufficient space in the stack ? */
+ if((s->len + n) > s->size) {
+ rte_spinlock_unlock(>sl);
+ return -ENOENT;
+ }
+
+ /* Add elements back into the cache */
+ for (index = 0; index < n; ++index, obj_table++)
+ cache_objs[index] = *obj_table;
+
+ s->len += n;
+
+ rte_spinlock_unlock(>sl);
+
