Imported Upstream version 16.04

[deb_dpdk.git] / lib / librte_kni / rte_kni_fifo.h

diff --git a/lib/librte_kni/rte_kni_fifo.h b/lib/librte_kni/rte_kni_fifo.h
new file mode 100644 (file)
index 0000000..8cb8587
--- /dev/null
+++ b/lib/librte_kni/rte_kni_fifo.h
@@ -0,0 +1,93 @@
+/*-
+ *   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.
+ */
+
+
+
+/**
+ * Initializes the kni fifo structure
+ */
+static void
+kni_fifo_init(struct rte_kni_fifo *fifo, unsigned size)
+{
+       /* Ensure size is power of 2 */
+       if (size & (size - 1))
+               rte_panic("KNI fifo size must be power of 2\n");
+
+       fifo->write = 0;
+       fifo->read = 0;
+       fifo->len = size;
+       fifo->elem_size = sizeof(void *);
+}
+
+/**
+ * Adds num elements into the fifo. Return the number actually written
+ */
+static inline unsigned
+kni_fifo_put(struct rte_kni_fifo *fifo, void **data, unsigned num)
+{
+       unsigned i = 0;
+       unsigned fifo_write = fifo->write;
+       unsigned fifo_read = fifo->read;
+       unsigned new_write = fifo_write;
+
+       for (i = 0; i < num; i++) {
+               new_write = (new_write + 1) & (fifo->len - 1);
+
+               if (new_write == fifo_read)
+                       break;
+               fifo->buffer[fifo_write] = data[i];
+               fifo_write = new_write;
+       }
+       fifo->write = fifo_write;
+       return i;
+}
+
+/**
+ * Get up to num elements from the fifo. Return the number actully read
+ */
+static inline unsigned
+kni_fifo_get(struct rte_kni_fifo *fifo, void **data, unsigned num)
+{
+       unsigned i = 0;
+       unsigned new_read = fifo->read;
+       unsigned fifo_write = fifo->write;
+       for (i = 0; i < num; i++) {
+               if (new_read == fifo_write)
+                       break;
+
+               data[i] = fifo->buffer[new_read];
+               new_read = (new_read + 1) & (fifo->len - 1);
+       }
+       fifo->read = new_read;
+       return i;
+}