numam-dpdk/lib/librte_kni/rte_kni_fifo.h
Bruce Richardson 369991d997 lib: use SPDX tag for Intel copyright files
Replace the BSD license header with the SPDX tag for files
with only an Intel copyright on them.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
2018-01-04 22:41:39 +01:00

74 lines
1.5 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2010-2014 Intel Corporation
*/
/**
* 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 actually 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;
}
/**
* Get the num of elements in the fifo
*/
static inline uint32_t
kni_fifo_count(struct rte_kni_fifo *fifo)
{
return (fifo->len + fifo->write - fifo->read) & (fifo->len - 1);
}