diff options
Diffstat (limited to 'lib/librte_kni/rte_kni_fifo.h')
-rw-r--r-- | lib/librte_kni/rte_kni_fifo.h | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/lib/librte_kni/rte_kni_fifo.h b/lib/librte_kni/rte_kni_fifo.h new file mode 100644 index 00000000..8cb85873 --- /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; +} |