diff options
Diffstat (limited to 'drivers/event/sw/event_ring.h')
| -rw-r--r-- | drivers/event/sw/event_ring.h | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/drivers/event/sw/event_ring.h b/drivers/event/sw/event_ring.h new file mode 100644 index 00000000..cdaee95d --- /dev/null +++ b/drivers/event/sw/event_ring.h @@ -0,0 +1,185 @@ +/*- + * BSD LICENSE + * + * Copyright(c) 2016-2017 Intel Corporation. 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. + */ + +/* + * Generic ring structure for passing events from one core to another. + * + * Used by the software scheduler for the producer and consumer rings for + * each port, i.e. for passing events from worker cores to scheduler and + * vice-versa. Designed for single-producer, single-consumer use with two + * cores working on each ring. + */ + +#ifndef _EVENT_RING_ +#define _EVENT_RING_ + +#include <stdint.h> + +#include <rte_common.h> +#include <rte_memory.h> +#include <rte_malloc.h> + +#define QE_RING_NAMESIZE 32 + +struct qe_ring { + char name[QE_RING_NAMESIZE] __rte_cache_aligned; + uint32_t ring_size; /* size of memory block allocated to the ring */ + uint32_t mask; /* mask for read/write values == ring_size -1 */ + uint32_t size; /* actual usable space in the ring */ + volatile uint32_t write_idx __rte_cache_aligned; + volatile uint32_t read_idx __rte_cache_aligned; + + struct rte_event ring[0] __rte_cache_aligned; +}; + +#ifndef force_inline +#define force_inline inline __attribute__((always_inline)) +#endif + +static inline struct qe_ring * +qe_ring_create(const char *name, unsigned int size, unsigned int socket_id) +{ + struct qe_ring *retval; + const uint32_t ring_size = rte_align32pow2(size + 1); + size_t memsize = sizeof(*retval) + + (ring_size * sizeof(retval->ring[0])); + + retval = rte_zmalloc_socket(NULL, memsize, 0, socket_id); + if (retval == NULL) + goto end; + + snprintf(retval->name, sizeof(retval->name), "EVDEV_RG_%s", name); + retval->ring_size = ring_size; + retval->mask = ring_size - 1; + retval->size = size; +end: + return retval; +} + +static inline void +qe_ring_destroy(struct qe_ring *r) +{ + rte_free(r); +} + +static force_inline unsigned int +qe_ring_count(const struct qe_ring *r) +{ + return r->write_idx - r->read_idx; +} + +static force_inline unsigned int +qe_ring_free_count(const struct qe_ring *r) +{ + return r->size - qe_ring_count(r); +} + +static force_inline unsigned int +qe_ring_enqueue_burst(struct qe_ring *r, const struct rte_event *qes, + unsigned int nb_qes, uint16_t *free_count) +{ + const uint32_t size = r->size; + const uint32_t mask = r->mask; + const uint32_t read = r->read_idx; + uint32_t write = r->write_idx; + const uint32_t space = read + size - write; + uint32_t i; + + if (space < nb_qes) + nb_qes = space; + + for (i = 0; i < nb_qes; i++, write++) + r->ring[write & mask] = qes[i]; + + rte_smp_wmb(); + + if (nb_qes != 0) + r->write_idx = write; + + *free_count = space - nb_qes; + + return nb_qes; +} + +static force_inline unsigned int +qe_ring_enqueue_burst_with_ops(struct qe_ring *r, const struct rte_event *qes, + unsigned int nb_qes, uint8_t *ops) +{ + const uint32_t size = r->size; + const uint32_t mask = r->mask; + const uint32_t read = r->read_idx; + uint32_t write = r->write_idx; + const uint32_t space = read + size - write; + uint32_t i; + + if (space < nb_qes) + nb_qes = space; + + for (i = 0; i < nb_qes; i++, write++) { + r->ring[write & mask] = qes[i]; + r->ring[write & mask].op = ops[i]; + } + + rte_smp_wmb(); + + if (nb_qes != 0) + r->write_idx = write; + + return nb_qes; +} + +static force_inline unsigned int +qe_ring_dequeue_burst(struct qe_ring *r, struct rte_event *qes, + unsigned int nb_qes) +{ + const uint32_t mask = r->mask; + uint32_t read = r->read_idx; + const uint32_t write = r->write_idx; + const uint32_t items = write - read; + uint32_t i; + + if (items < nb_qes) + nb_qes = items; + + + for (i = 0; i < nb_qes; i++, read++) + qes[i] = r->ring[read & mask]; + + rte_smp_rmb(); + + if (nb_qes != 0) + r->read_idx += nb_qes; + + return nb_qes; +} + +#endif |