Re: [dpdk-dev] [PATCH 2/5] lib/ring: add template to support different element sizes

["Ananyev, Konstantin" <konstantin.ananyev@intel.com>]

> 
> 
> Add templates to support creating ring APIs with different
> ring element sizes.
> 
> Signed-off-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
> Reviewed-by: Dharmik Thakkar <dharmik.thakkar@arm.com>
> Reviewed-by: Gavin Hu <gavin.hu@arm.com>
> Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
> ---
>  lib/librte_ring/Makefile            |   4 +-
>  lib/librte_ring/meson.build         |   4 +-
>  lib/librte_ring/rte_ring_template.c |  46 ++++
>  lib/librte_ring/rte_ring_template.h | 330 ++++++++++++++++++++++++++++
>  4 files changed, 382 insertions(+), 2 deletions(-)
>  create mode 100644 lib/librte_ring/rte_ring_template.c
>  create mode 100644 lib/librte_ring/rte_ring_template.h
> 
> diff --git a/lib/librte_ring/Makefile b/lib/librte_ring/Makefile
> index 4c8410229..818898110 100644
> --- a/lib/librte_ring/Makefile
> +++ b/lib/librte_ring/Makefile
> @@ -19,6 +19,8 @@ SRCS-$(CONFIG_RTE_LIBRTE_RING) := rte_ring.c
>  # install includes
>  SYMLINK-$(CONFIG_RTE_LIBRTE_RING)-include := rte_ring.h \
>  					rte_ring_generic.h \
> -					rte_ring_c11_mem.h
> +					rte_ring_c11_mem.h \
> +					rte_ring_template.h \
> +					rte_ring_template.c
> 
>  include $(RTE_SDK)/mk/rte.lib.mk
> diff --git a/lib/librte_ring/meson.build b/lib/librte_ring/meson.build
> index 74219840a..e4e208a7c 100644
> --- a/lib/librte_ring/meson.build
> +++ b/lib/librte_ring/meson.build
> @@ -5,7 +5,9 @@ version = 2
>  sources = files('rte_ring.c')
>  headers = files('rte_ring.h',
>  		'rte_ring_c11_mem.h',
> -		'rte_ring_generic.h')
> +		'rte_ring_generic.h',
> +		'rte_ring_template.h',
> +		'rte_ring_template.c')
> 
>  # rte_ring_create_elem and rte_ring_get_memsize_elem are experimental
>  allow_experimental_apis = true
> diff --git a/lib/librte_ring/rte_ring_template.c b/lib/librte_ring/rte_ring_template.c
> new file mode 100644
> index 000000000..1ca593f95
> --- /dev/null
> +++ b/lib/librte_ring/rte_ring_template.c
> @@ -0,0 +1,46 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright (c) 2019 Arm Limited
> + */
> +
> +#include <stdio.h>
> +#include <stdarg.h>
> +#include <string.h>
> +#include <stdint.h>
> +#include <inttypes.h>
> +#include <errno.h>
> +#include <sys/queue.h>
> +
> +#include <rte_common.h>
> +#include <rte_log.h>
> +#include <rte_memory.h>
> +#include <rte_memzone.h>
> +#include <rte_malloc.h>
> +#include <rte_launch.h>
> +#include <rte_eal.h>
> +#include <rte_eal_memconfig.h>
> +#include <rte_atomic.h>
> +#include <rte_per_lcore.h>
> +#include <rte_lcore.h>
> +#include <rte_branch_prediction.h>
> +#include <rte_errno.h>
> +#include <rte_string_fns.h>
> +#include <rte_spinlock.h>
> +#include <rte_tailq.h>
> +
> +#include "rte_ring.h"
> +
> +/* return the size of memory occupied by a ring */
> +ssize_t
> +__RTE_RING_CONCAT(rte_ring_get_memsize)(unsigned count)
> +{
> +	return rte_ring_get_memsize_elem(count, RTE_RING_TMPLT_ELEM_SIZE);
> +}
> +
> +/* create the ring */
> +struct rte_ring *
> +__RTE_RING_CONCAT(rte_ring_create)(const char *name, unsigned count,
> +		int socket_id, unsigned flags)
> +{
> +	return rte_ring_create_elem(name, count, RTE_RING_TMPLT_ELEM_SIZE,
> +		socket_id, flags);
> +}
> diff --git a/lib/librte_ring/rte_ring_template.h b/lib/librte_ring/rte_ring_template.h
> new file mode 100644
> index 000000000..b9b14dfbb
> --- /dev/null
> +++ b/lib/librte_ring/rte_ring_template.h
> @@ -0,0 +1,330 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright (c) 2019 Arm Limited
> + */
> +
> +#ifndef _RTE_RING_TEMPLATE_H_
> +#define _RTE_RING_TEMPLATE_H_
> +
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
> +
> +#include <stdio.h>
> +#include <stdint.h>
> +#include <sys/queue.h>
> +#include <errno.h>
> +#include <rte_common.h>
> +#include <rte_config.h>
> +#include <rte_memory.h>
> +#include <rte_lcore.h>
> +#include <rte_atomic.h>
> +#include <rte_branch_prediction.h>
> +#include <rte_memzone.h>
> +#include <rte_pause.h>
> +#include <rte_ring.h>
> +
> +/* Ring API suffix name - used to append to API names */
> +#ifndef RTE_RING_TMPLT_API_SUFFIX
> +#error RTE_RING_TMPLT_API_SUFFIX not defined
> +#endif
> +
> +/* Ring's element size in bits, should be a power of 2 */
> +#ifndef RTE_RING_TMPLT_ELEM_SIZE
> +#error RTE_RING_TMPLT_ELEM_SIZE not defined
> +#endif
> +
> +/* Type of ring elements */
> +#ifndef RTE_RING_TMPLT_ELEM_TYPE
> +#error RTE_RING_TMPLT_ELEM_TYPE not defined
> +#endif
> +
> +#define _rte_fuse(a, b) a##_##b
> +#define __rte_fuse(a, b) _rte_fuse(a, b)
> +#define __RTE_RING_CONCAT(a) __rte_fuse(a, RTE_RING_TMPLT_API_SUFFIX)
> +
> +/* Calculate the memory size needed for a ring */
> +RTE_RING_TMPLT_EXPERIMENTAL
> +ssize_t __RTE_RING_CONCAT(rte_ring_get_memsize)(unsigned count);
> +
> +/* Create a new ring named *name* in memory. */
> +RTE_RING_TMPLT_EXPERIMENTAL
> +struct rte_ring *
> +__RTE_RING_CONCAT(rte_ring_create)(const char *name, unsigned count,
> +					int socket_id, unsigned flags);


Just an idea - probably same thing can be achieved in a different way.
Instead of all these defines - replace ENQUEUE_PTRS/DEQUEUE_PTRS macros
with static inline functions and then make all internal functions, i.e. __rte_ring_do_dequeue()
to accept enqueue/dequeue function pointer as a parameter.
Then let say default rte_ring_mc_dequeue_bulk will do:

rte_ring_mc_dequeue_bulk(struct rte_ring *r, void **obj_table,
                unsigned int n, unsigned int *available)
{
        return __rte_ring_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_FIXED,
                        __IS_MC, available, dequeue_ptr_default);
}

Then if someone will like to define ring functions forelt_size==X, all he would need to do:
1. define his own enqueue/dequeuer functions.
2. do something like:
rte_ring_mc_dequeue_bulk(struct rte_ring *r, void **obj_table,
                unsigned int n, unsigned int *available)
{
        return __rte_ring_do_dequeue(r, obj_table, n, RTE_RING_QUEUE_FIXED,
                        __IS_MC, available, dequeue_X);
}

Konstantin


> +
> +/**
> + * @internal Enqueue several objects on the ring
> + */
> +static __rte_always_inline unsigned int
> +__RTE_RING_CONCAT(__rte_ring_do_enqueue)(struct rte_ring *r,
> +		RTE_RING_TMPLT_ELEM_TYPE const *obj_table, unsigned int n,
> +		enum rte_ring_queue_behavior behavior, unsigned int is_sp,
> +		unsigned int *free_space)
> +{
> +	uint32_t prod_head, prod_next;
> +	uint32_t free_entries;
> +
> +	n = __rte_ring_move_prod_head(r, is_sp, n, behavior,
> +			&prod_head, &prod_next, &free_entries);
> +	if (n == 0)
> +		goto end;
> +
> +	ENQUEUE_PTRS(r, &r[1], prod_head, obj_table, n,
> +		RTE_RING_TMPLT_ELEM_TYPE);
> +
> +	update_tail(&r->prod, prod_head, prod_next, is_sp, 1);
> +end:
> +	if (free_space != NULL)
> +		*free_space = free_entries - n;
> +	return n;
> +}
> +
> +/**
> + * @internal Dequeue several objects from the ring
> + */
> +static __rte_always_inline unsigned int
> +__RTE_RING_CONCAT(__rte_ring_do_dequeue)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_table, unsigned int n,
> +	enum rte_ring_queue_behavior behavior, unsigned int is_sc,
> +	unsigned int *available)
> +{
> +	uint32_t cons_head, cons_next;
> +	uint32_t entries;
> +
> +	n = __rte_ring_move_cons_head(r, (int)is_sc, n, behavior,
> +			&cons_head, &cons_next, &entries);
> +	if (n == 0)
> +		goto end;
> +
> +	DEQUEUE_PTRS(r, &r[1], cons_head, obj_table, n,
> +		RTE_RING_TMPLT_ELEM_TYPE);
> +
> +	update_tail(&r->cons, cons_head, cons_next, is_sc, 0);
> +
> +end:
> +	if (available != NULL)
> +		*available = entries - n;
> +	return n;
> +}
> +
> +
> +/**
> + * Enqueue several objects on the ring (multi-producers safe).
> + */
> +static __rte_always_inline unsigned int
> +__RTE_RING_CONCAT(rte_ring_mp_enqueue_bulk)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE const *obj_table, unsigned int n,
> +	unsigned int *free_space)
> +{
> +	return __RTE_RING_CONCAT(__rte_ring_do_enqueue)(r, obj_table, n,
> +			RTE_RING_QUEUE_FIXED, __IS_MP, free_space);
> +}
> +
> +/**
> + * Enqueue several objects on a ring (NOT multi-producers safe).
> + */
> +static __rte_always_inline unsigned int
> +__RTE_RING_CONCAT(rte_ring_sp_enqueue_bulk)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE const *obj_table, unsigned int n,
> +	unsigned int *free_space)
> +{
> +	return __RTE_RING_CONCAT(__rte_ring_do_enqueue)(r, obj_table, n,
> +			RTE_RING_QUEUE_FIXED, __IS_SP, free_space);
> +}
> +
> +/**
> + * Enqueue several objects on a ring.
> + */
> +static __rte_always_inline unsigned int
> +__RTE_RING_CONCAT(rte_ring_enqueue_bulk)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE const *obj_table, unsigned int n,
> +	unsigned int *free_space)
> +{
> +	return __RTE_RING_CONCAT(__rte_ring_do_enqueue)(r, obj_table, n,
> +			RTE_RING_QUEUE_FIXED, r->prod.single, free_space);
> +}
> +
> +/**
> + * Enqueue one object on a ring (multi-producers safe).
> + */
> +static __rte_always_inline int
> +__RTE_RING_CONCAT(rte_ring_mp_enqueue)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE obj)
> +{
> +	return __RTE_RING_CONCAT(rte_ring_mp_enqueue_bulk)(r, &obj, 1, NULL) ?
> +			0 : -ENOBUFS;
> +}
> +
> +/**
> + * Enqueue one object on a ring (NOT multi-producers safe).
> + */
> +static __rte_always_inline int
> +__RTE_RING_CONCAT(rte_ring_sp_enqueue)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE obj)
> +{
> +	return __RTE_RING_CONCAT(rte_ring_sp_enqueue_bulk)(r, &obj, 1, NULL) ?
> +			0 : -ENOBUFS;
> +}
> +
> +/**
> + * Enqueue one object on a ring.
> + */
> +static __rte_always_inline int
> +__RTE_RING_CONCAT(rte_ring_enqueue)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj)
> +{
> +	return __RTE_RING_CONCAT(rte_ring_enqueue_bulk)(r, obj, 1, NULL) ?
> +			0 : -ENOBUFS;
> +}
> +
> +/**
> + * Dequeue several objects from a ring (multi-consumers safe).
> + */
> +static __rte_always_inline unsigned int
> +__RTE_RING_CONCAT(rte_ring_mc_dequeue_bulk)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_table, unsigned int n,
> +	unsigned int *available)
> +{
> +	return __RTE_RING_CONCAT(__rte_ring_do_dequeue)(r, obj_table, n,
> +			RTE_RING_QUEUE_FIXED, __IS_MC, available);
> +}
> +
> +/**
> + * Dequeue several objects from a ring (NOT multi-consumers safe).
> + */
> +static __rte_always_inline unsigned int
> +__RTE_RING_CONCAT(rte_ring_sc_dequeue_bulk)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_table, unsigned int n,
> +	unsigned int *available)
> +{
> +	return __RTE_RING_CONCAT(__rte_ring_do_dequeue)(r, obj_table, n,
> +			RTE_RING_QUEUE_FIXED, __IS_SC, available);
> +}
> +
> +/**
> + * Dequeue several objects from a ring.
> + */
> +static __rte_always_inline unsigned int
> +__RTE_RING_CONCAT(rte_ring_dequeue_bulk)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_table, unsigned int n,
> +	unsigned int *available)
> +{
> +	return __RTE_RING_CONCAT(__rte_ring_do_dequeue)(r, obj_table, n,
> +			RTE_RING_QUEUE_FIXED, r->cons.single, available);
> +}
> +
> +/**
> + * Dequeue one object from a ring (multi-consumers safe).
> + */
> +static __rte_always_inline int
> +__RTE_RING_CONCAT(rte_ring_mc_dequeue)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_p)
> +{
> +	return __RTE_RING_CONCAT(rte_ring_mc_dequeue_bulk)(r, obj_p, 1, NULL) ?
> +			0 : -ENOENT;
> +}
> +
> +/**
> + * Dequeue one object from a ring (NOT multi-consumers safe).
> + */
> +static __rte_always_inline int
> +__RTE_RING_CONCAT(rte_ring_sc_dequeue)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_p)
> +{
> +	return __RTE_RING_CONCAT(rte_ring_sc_dequeue_bulk)(r, obj_p, 1, NULL) ?
> +			0 : -ENOENT;
> +}
> +
> +/**
> + * Dequeue one object from a ring.
> + */
> +static __rte_always_inline int
> +__RTE_RING_CONCAT(rte_ring_dequeue)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_p)
> +{
> +	return __RTE_RING_CONCAT(rte_ring_dequeue_bulk)(r, obj_p, 1, NULL) ?
> +			0 : -ENOENT;
> +}
> +
> +/**
> + * Enqueue several objects on the ring (multi-producers safe).
> + */
> +static __rte_always_inline unsigned
> +__RTE_RING_CONCAT(rte_ring_mp_enqueue_burst)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_table,
> +			 unsigned int n, unsigned int *free_space)
> +{
> +	return __RTE_RING_CONCAT(__rte_ring_do_enqueue)(r, obj_table, n,
> +			RTE_RING_QUEUE_VARIABLE, __IS_MP, free_space);
> +}
> +
> +/**
> + * Enqueue several objects on a ring (NOT multi-producers safe).
> + */
> +static __rte_always_inline unsigned
> +__RTE_RING_CONCAT(rte_ring_sp_enqueue_burst)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_table,
> +			 unsigned int n, unsigned int *free_space)
> +{
> +	return __RTE_RING_CONCAT(__rte_ring_do_enqueue)(r, obj_table, n,
> +			RTE_RING_QUEUE_VARIABLE, __IS_SP, free_space);
> +}
> +
> +/**
> + * Enqueue several objects on a ring.
> + */
> +static __rte_always_inline unsigned
> +__RTE_RING_CONCAT(rte_ring_enqueue_burst)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_table, unsigned int n,
> +	unsigned int *free_space)
> +{
> +	return __RTE_RING_CONCAT(__rte_ring_do_enqueue)(r, obj_table, n,
> +			RTE_RING_QUEUE_VARIABLE, r->prod.single, free_space);
> +}
> +
> +/**
> + * Dequeue several objects from a ring (multi-consumers safe). When the request
> + * objects are more than the available objects, only dequeue the actual number
> + * of objects
> + */
> +static __rte_always_inline unsigned
> +__RTE_RING_CONCAT(rte_ring_mc_dequeue_burst)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_table, unsigned int n,
> +	unsigned int *available)
> +{
> +	return __RTE_RING_CONCAT(__rte_ring_do_dequeue)(r, obj_table, n,
> +			RTE_RING_QUEUE_VARIABLE, __IS_MC, available);
> +}
> +
> +/**
> + * Dequeue several objects from a ring (NOT multi-consumers safe).When the
> + * request objects are more than the available objects, only dequeue the
> + * actual number of objects
> + */
> +static __rte_always_inline unsigned
> +__RTE_RING_CONCAT(rte_ring_sc_dequeue_burst)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_table, unsigned int n,
> +	unsigned int *available)
> +{
> +	return __RTE_RING_CONCAT(__rte_ring_do_dequeue)(r, obj_table, n,
> +			RTE_RING_QUEUE_VARIABLE, __IS_SC, available);
> +}
> +
> +/**
> + * Dequeue multiple objects from a ring up to a maximum number.
> + */
> +static __rte_always_inline unsigned
> +__RTE_RING_CONCAT(rte_ring_dequeue_burst)(struct rte_ring *r,
> +	RTE_RING_TMPLT_ELEM_TYPE *obj_table, unsigned int n,
> +	unsigned int *available)
> +{
> +	return __RTE_RING_CONCAT(__rte_ring_do_dequeue)(r, obj_table, n,
> +				RTE_RING_QUEUE_VARIABLE,
> +				r->cons.single, available);
> +}
> +
> +#ifdef __cplusplus
> +}
> +#endif
> +
> +#endif /* _RTE_RING_TEMPLATE_H_ */
> --
> 2.17.1