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38 * Initializes the kni fifo structure
41 kni_fifo_init(struct rte_kni_fifo *fifo, unsigned size)
43 /* Ensure size is power of 2 */
44 if (size & (size - 1))
45 rte_panic("KNI fifo size must be power of 2\n");
50 fifo->elem_size = sizeof(void *);
54 * Adds num elements into the fifo. Return the number actually written
56 static inline unsigned
57 kni_fifo_put(struct rte_kni_fifo *fifo, void **data, unsigned num)
60 unsigned fifo_write = fifo->write;
61 unsigned fifo_read = fifo->read;
62 unsigned new_write = fifo_write;
64 for (i = 0; i < num; i++) {
65 new_write = (new_write + 1) & (fifo->len - 1);
67 if (new_write == fifo_read)
69 fifo->buffer[fifo_write] = data[i];
70 fifo_write = new_write;
72 fifo->write = fifo_write;
77 * Get up to num elements from the fifo. Return the number actully read
79 static inline unsigned
80 kni_fifo_get(struct rte_kni_fifo *fifo, void **data, unsigned num)
83 unsigned new_read = fifo->read;
84 unsigned fifo_write = fifo->write;
85 for (i = 0; i < num; i++) {
86 if (new_read == fifo_write)
89 data[i] = fifo->buffer[new_read];
90 new_read = (new_read + 1) & (fifo->len - 1);
92 fifo->read = new_read;