numam-dpdk/drivers/event/sw/event_ring.h
Bruce Richardson 5566a3e358 drivers: 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

154 lines
3.4 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2016-2017 Intel Corporation
*/
/*
* 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;
};
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 __rte_always_inline unsigned int
qe_ring_count(const struct qe_ring *r)
{
return r->write_idx - r->read_idx;
}
static __rte_always_inline unsigned int
qe_ring_free_count(const struct qe_ring *r)
{
return r->size - qe_ring_count(r);
}
static __rte_always_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 __rte_always_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 __rte_always_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