numam-dpdk/lib/librte_eventdev/rte_event_ring.h
Honnappa Nagarahalli 867b6d6180 eventdev: use custom element size rings
Use custom element size ring APIs to replace event ring
implementation. This avoids code duplication.

Signed-off-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Reviewed-by: Gavin Hu <gavin.hu@arm.com>
Reviewed-by: Ola Liljedahl <ola.liljedahl@arm.com>
Reviewed-by: Jerin Jacob <jerinj@marvell.com>
Acked-by: Mattias Rönnblom <mattias.ronnblom@ericsson.com>
2020-01-19 19:32:50 +01:00

270 lines
8.2 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2016-2017 Intel Corporation
* Copyright(c) 2019 Arm Limited
*/
/**
* @file
* RTE Event Ring
*
* This provides a ring implementation for passing rte_event structures
* from one core to another.
*/
#ifndef _RTE_EVENT_RING_
#define _RTE_EVENT_RING_
#include <stdint.h>
#include <rte_common.h>
#include <rte_memory.h>
#include <rte_malloc.h>
#include <rte_ring.h>
#include <rte_ring_elem.h>
#include "rte_eventdev.h"
#define RTE_TAILQ_EVENT_RING_NAME "RTE_EVENT_RING"
/**
* Generic ring structure for passing rte_event objects from core to core.
*
* Based on the primitives given in the rte_ring library. Designed to be
* used inside software eventdev implementations and by applications
* directly as needed.
*/
struct rte_event_ring {
struct rte_ring r;
};
/**
* Returns the number of events in the ring
*
* @param r
* pointer to the event ring
* @return
* the number of events in the ring
*/
static __rte_always_inline unsigned int
rte_event_ring_count(const struct rte_event_ring *r)
{
return rte_ring_count(&r->r);
}
/**
* Returns the amount of free space in the ring
*
* @param r
* pointer to the event ring
* @return
* the number of free slots in the ring, i.e. the number of events that
* can be successfully enqueued before dequeue must be called
*/
static __rte_always_inline unsigned int
rte_event_ring_free_count(const struct rte_event_ring *r)
{
return rte_ring_free_count(&r->r);
}
/**
* Enqueue a set of events onto a ring
*
* Note: this API enqueues by copying the events themselves onto the ring,
* rather than just placing a pointer to each event onto the ring. This
* means that statically-allocated events can safely be enqueued by this
* API.
*
* @param r
* pointer to the event ring
* @param events
* pointer to an array of struct rte_event objects
* @param n
* number of events in the array to enqueue
* @param free_space
* if non-null, is updated to indicate the amount of free space in the
* ring once the enqueue has completed.
* @return
* the number of elements, n', enqueued to the ring, 0 <= n' <= n
*/
static __rte_always_inline unsigned int
rte_event_ring_enqueue_burst(struct rte_event_ring *r,
const struct rte_event *events,
unsigned int n, uint16_t *free_space)
{
unsigned int num;
uint32_t space;
num = rte_ring_enqueue_burst_elem(&r->r, events,
sizeof(struct rte_event), n,
&space);
if (free_space != NULL)
*free_space = space;
return num;
}
/**
* Dequeue a set of events from a ring
*
* Note: this API does not work with pointers to events, rather it copies
* the events themselves to the destination ``events`` buffer.
*
* @param r
* pointer to the event ring
* @param events
* pointer to an array to hold the struct rte_event objects
* @param n
* number of events that can be held in the ``events`` array
* @param available
* if non-null, is updated to indicate the number of events remaining in
* the ring once the dequeue has completed
* @return
* the number of elements, n', dequeued from the ring, 0 <= n' <= n
*/
static __rte_always_inline unsigned int
rte_event_ring_dequeue_burst(struct rte_event_ring *r,
struct rte_event *events,
unsigned int n, uint16_t *available)
{
unsigned int num;
uint32_t remaining;
num = rte_ring_dequeue_burst_elem(&r->r, events,
sizeof(struct rte_event), n,
&remaining);
if (available != NULL)
*available = remaining;
return num;
}
/*
* Initializes an already-allocated ring structure
*
* @param r
* pointer to the ring memory to be initialized
* @param name
* name to be given to the ring
* @param count
* the number of elements to be stored in the ring. If the flag
* ``RING_F_EXACT_SZ`` is not set, this must be a power of 2, and the actual
* usable space in the ring will be ``count - 1`` entries. If the flag
* ``RING_F_EXACT_SZ`` is set, the this can be any value up to the ring size
* limit - 1, and the usable space will be exactly that requested.
* @param flags
* An OR of the following:
* - RING_F_SP_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "single-producer". Otherwise, it is "multi-producers".
* - RING_F_SC_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "single-consumer". Otherwise, it is "multi-consumers".
* - RING_F_EXACT_SZ: If this flag is set, the ``count`` parameter is to
* be taken as the exact usable size of the ring, and as such does not
* need to be a power of 2. The underlying ring memory should be a
* power-of-2 size greater than the count value.
* @return
* 0 on success, or a negative value on error.
*/
int
rte_event_ring_init(struct rte_event_ring *r, const char *name,
unsigned int count, unsigned int flags);
/*
* Create an event ring structure
*
* This function allocates memory and initializes an event ring inside that
* memory.
*
* @param name
* name to be given to the ring
* @param count
* the number of elements to be stored in the ring. If the flag
* ``RING_F_EXACT_SZ`` is not set, this must be a power of 2, and the actual
* usable space in the ring will be ``count - 1`` entries. If the flag
* ``RING_F_EXACT_SZ`` is set, the this can be any value up to the ring size
* limit - 1, and the usable space will be exactly that requested.
* @param socket_id
* The *socket_id* argument is the socket identifier in case of
* NUMA. The value can be *SOCKET_ID_ANY* if there is no NUMA
* constraint for the reserved zone.
* @param flags
* An OR of the following:
* - RING_F_SP_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "single-producer". Otherwise, it is "multi-producers".
* - RING_F_SC_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "single-consumer". Otherwise, it is "multi-consumers".
* - RING_F_EXACT_SZ: If this flag is set, the ``count`` parameter is to
* be taken as the exact usable size of the ring, and as such does not
* need to be a power of 2. The underlying ring memory should be a
* power-of-2 size greater than the count value.
* @return
* On success, the pointer to the new allocated ring. NULL on error with
* rte_errno set appropriately. Possible errno values include:
* - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
* - E_RTE_SECONDARY - function was called from a secondary process instance
* - EINVAL - count provided is not a power of 2
* - ENOSPC - the maximum number of memzones has already been allocated
* - EEXIST - a memzone with the same name already exists
* - ENOMEM - no appropriate memory area found in which to create memzone
*/
struct rte_event_ring *
rte_event_ring_create(const char *name, unsigned int count, int socket_id,
unsigned int flags);
/**
* Search for an event ring based on its name
*
* @param name
* The name of the ring.
* @return
* The pointer to the ring matching the name, or NULL if not found,
* with rte_errno set appropriately. Possible rte_errno values include:
* - ENOENT - required entry not available to return.
*/
struct rte_event_ring *
rte_event_ring_lookup(const char *name);
/**
* De-allocate all memory used by the ring.
*
* @param r
* Ring to free
*/
void
rte_event_ring_free(struct rte_event_ring *r);
/**
* Return the size of the event ring.
*
* @param r
* A pointer to the ring structure.
* @return
* The size of the data store used by the ring.
* NOTE: this is not the same as the usable space in the ring. To query that
* use ``rte_ring_get_capacity()``.
*/
static inline unsigned int
rte_event_ring_get_size(const struct rte_event_ring *r)
{
return rte_ring_get_size(&r->r);
}
/**
* Return the number of elements which can be stored in the event ring.
*
* @param r
* A pointer to the ring structure.
* @return
* The usable size of the ring.
*/
static inline unsigned int
rte_event_ring_get_capacity(const struct rte_event_ring *r)
{
return rte_ring_get_capacity(&r->r);
}
#endif