[v5,01/10] memarea: introduce memarea library

Message ID tencent_FEE531AF1F40D6FD8FB249B7DE9B04E7E408@qq.com (mailing list archive)
State Superseded, archived
Delegated to: Thomas Monjalon
Headers
Series [v5,01/10] memarea: introduce memarea library |

Checks

Context Check Description
ci/checkpatch success coding style OK

Commit Message

datshan Oct. 5, 2022, 4:09 a.m. UTC
  From: Chengwen Feng <fengchengwen@huawei.com>

The memarea library is an allocator of variable-size object which based
on a memory region.

This patch provides create/destroy API.

Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
---
 MAINTAINERS                            |   5 +
 doc/api/doxy-api-index.md              |   3 +-
 doc/api/doxy-api.conf.in               |   1 +
 doc/guides/prog_guide/index.rst        |   1 +
 doc/guides/prog_guide/memarea_lib.rst  |  39 ++++++
 doc/guides/rel_notes/release_22_11.rst |   6 +
 lib/eal/common/eal_common_log.c        |   1 +
 lib/eal/include/rte_log.h              |   1 +
 lib/memarea/memarea_private.h          |  30 +++++
 lib/memarea/meson.build                |  16 +++
 lib/memarea/rte_memarea.c              | 157 +++++++++++++++++++++++++
 lib/memarea/rte_memarea.h              | 145 +++++++++++++++++++++++
 lib/memarea/version.map                |  12 ++
 lib/meson.build                        |   1 +
 14 files changed, 417 insertions(+), 1 deletion(-)
 create mode 100644 doc/guides/prog_guide/memarea_lib.rst
 create mode 100644 lib/memarea/memarea_private.h
 create mode 100644 lib/memarea/meson.build
 create mode 100644 lib/memarea/rte_memarea.c
 create mode 100644 lib/memarea/rte_memarea.h
 create mode 100644 lib/memarea/version.map
  

Comments

Mattias Rönnblom Oct. 6, 2022, 8:15 p.m. UTC | #1
On 2022-10-05 06:09, datshan wrote:
> From: Chengwen Feng <fengchengwen@huawei.com>
> 
> The memarea library is an allocator of variable-size object which based
> on a memory region.
> 
> This patch provides create/destroy API.
> 
> Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
> ---
>   MAINTAINERS                            |   5 +
>   doc/api/doxy-api-index.md              |   3 +-
>   doc/api/doxy-api.conf.in               |   1 +
>   doc/guides/prog_guide/index.rst        |   1 +
>   doc/guides/prog_guide/memarea_lib.rst  |  39 ++++++
>   doc/guides/rel_notes/release_22_11.rst |   6 +
>   lib/eal/common/eal_common_log.c        |   1 +
>   lib/eal/include/rte_log.h              |   1 +
>   lib/memarea/memarea_private.h          |  30 +++++
>   lib/memarea/meson.build                |  16 +++
>   lib/memarea/rte_memarea.c              | 157 +++++++++++++++++++++++++
>   lib/memarea/rte_memarea.h              | 145 +++++++++++++++++++++++
>   lib/memarea/version.map                |  12 ++
>   lib/meson.build                        |   1 +
>   14 files changed, 417 insertions(+), 1 deletion(-)
>   create mode 100644 doc/guides/prog_guide/memarea_lib.rst
>   create mode 100644 lib/memarea/memarea_private.h
>   create mode 100644 lib/memarea/meson.build
>   create mode 100644 lib/memarea/rte_memarea.c
>   create mode 100644 lib/memarea/rte_memarea.h
>   create mode 100644 lib/memarea/version.map
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index a55b379d73..b9c638221d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1550,6 +1550,11 @@ F: app/test/test_lpm*
>   F: app/test/test_func_reentrancy.c
>   F: app/test/test_xmmt_ops.h
>   
> +Memarea - EXPERIMENTAL
> +M: Chengwen Feng <fengchengwen@huawei.com>
> +F: lib/memarea
> +F: doc/guides/prog_guide/memarea_lib.rst
> +
>   Membership - EXPERIMENTAL
>   M: Yipeng Wang <yipeng1.wang@intel.com>
>   M: Sameh Gobriel <sameh.gobriel@intel.com>
> diff --git a/doc/api/doxy-api-index.md b/doc/api/doxy-api-index.md
> index de488c7abf..24456604f8 100644
> --- a/doc/api/doxy-api-index.md
> +++ b/doc/api/doxy-api-index.md
> @@ -62,7 +62,8 @@ The public API headers are grouped by topics:
>     [memzone](@ref rte_memzone.h),
>     [mempool](@ref rte_mempool.h),
>     [malloc](@ref rte_malloc.h),
> -  [memcpy](@ref rte_memcpy.h)
> +  [memcpy](@ref rte_memcpy.h),
> +  [memarea](@ref rte_memarea.h)
>   
>   - **timers**:
>     [cycles](@ref rte_cycles.h),
> diff --git a/doc/api/doxy-api.conf.in b/doc/api/doxy-api.conf.in
> index f0886c3bd1..8334ebcbd6 100644
> --- a/doc/api/doxy-api.conf.in
> +++ b/doc/api/doxy-api.conf.in
> @@ -53,6 +53,7 @@ INPUT                   = @TOPDIR@/doc/api/doxy-api-index.md \
>                             @TOPDIR@/lib/latencystats \
>                             @TOPDIR@/lib/lpm \
>                             @TOPDIR@/lib/mbuf \
> +                          @TOPDIR@/lib/memarea \
>                             @TOPDIR@/lib/member \
>                             @TOPDIR@/lib/mempool \
>                             @TOPDIR@/lib/meter \
> diff --git a/doc/guides/prog_guide/index.rst b/doc/guides/prog_guide/index.rst
> index 8564883018..e9015d65e3 100644
> --- a/doc/guides/prog_guide/index.rst
> +++ b/doc/guides/prog_guide/index.rst
> @@ -37,6 +37,7 @@ Programmer's Guide
>       hash_lib
>       toeplitz_hash_lib
>       efd_lib
> +    memarea_lib
>       member_lib
>       lpm_lib
>       lpm6_lib
> diff --git a/doc/guides/prog_guide/memarea_lib.rst b/doc/guides/prog_guide/memarea_lib.rst
> new file mode 100644
> index 0000000000..b96dad15f6
> --- /dev/null
> +++ b/doc/guides/prog_guide/memarea_lib.rst
> @@ -0,0 +1,39 @@
> +..  SPDX-License-Identifier: BSD-3-Clause
> +    Copyright(c) 2022 HiSilicon Limited
> +
> +Memarea Library
> +===============
> +
> +Introduction
> +------------
> +
> +The memarea library provides an allocator of variable-size objects, it is
> +oriented towards the application layer, which could provides 'region-based
> +memory management' function [1].
> +
> +The main features are as follows:
> +
> +* The default aligement size is ``RTE_CACHE_LINE_SIZE``.
> +
> +* The memory region can be initialized from the following memory sources:
> +  a) RTE memory: e.g. invoke ``rte_malloc_socket`` to obtain. b) System API:
> +  e.g. invoke posix_memalign to obtain. c) User provided address: it can be from
> +  extendedd memory as long as it is available. d) User provided memarea: it can
> +  be from another memarea.
> +
> +* It provides refcnt feature which could be useful in multi-reader scenario.
> +
> +* It supports MT-safe as long as it's specified at creation time.
> +
> +Library API Overview
> +--------------------
> +
> +The ``rte_memarea_create()`` function is used to create a memarea, the function
> +returns the pointer to the created memarea or ``NULL`` if the creation failed.
> +
> +The ``rte_memarea_destroy()`` function is used to destroy a memarea.
> +
> +Reference
> +---------
> +
> +[1] https://en.wikipedia.org/wiki/Region-based_memory_management
> diff --git a/doc/guides/rel_notes/release_22_11.rst b/doc/guides/rel_notes/release_22_11.rst
> index 5d8ef669b8..4c1f760b98 100644
> --- a/doc/guides/rel_notes/release_22_11.rst
> +++ b/doc/guides/rel_notes/release_22_11.rst
> @@ -55,6 +55,12 @@ New Features
>        Also, make sure to start the actual text at the margin.
>        =======================================================
>   
> +* **Added memarea library.**
> +
> +  The memarea library is an allocator of variable-size objects, it is oriented
> +  towards the application layer, which could provides 'region-based memory
> +  management' function.
> +
>   * **Added configuration for asynchronous flow connection tracking.**
>   
>     Added connection tracking action number hint to ``rte_flow_configure``
> diff --git a/lib/eal/common/eal_common_log.c b/lib/eal/common/eal_common_log.c
> index bd7b188ceb..3d62af59c6 100644
> --- a/lib/eal/common/eal_common_log.c
> +++ b/lib/eal/common/eal_common_log.c
> @@ -369,6 +369,7 @@ static const struct logtype logtype_strings[] = {
>   	{RTE_LOGTYPE_EFD,        "lib.efd"},
>   	{RTE_LOGTYPE_EVENTDEV,   "lib.eventdev"},
>   	{RTE_LOGTYPE_GSO,        "lib.gso"},
> +	{RTE_LOGTYPE_MEMAREA,    "lib.memarea"},
>   	{RTE_LOGTYPE_USER1,      "user1"},
>   	{RTE_LOGTYPE_USER2,      "user2"},
>   	{RTE_LOGTYPE_USER3,      "user3"},
> diff --git a/lib/eal/include/rte_log.h b/lib/eal/include/rte_log.h
> index 25ce42cdfc..708f3a39dd 100644
> --- a/lib/eal/include/rte_log.h
> +++ b/lib/eal/include/rte_log.h
> @@ -48,6 +48,7 @@ extern "C" {
>   #define RTE_LOGTYPE_EFD       18 /**< Log related to EFD. */
>   #define RTE_LOGTYPE_EVENTDEV  19 /**< Log related to eventdev. */
>   #define RTE_LOGTYPE_GSO       20 /**< Log related to GSO. */
> +#define RTE_LOGTYPE_MEMAREA   21 /**< Log related to memarea. */
>   
>   /* these log types can be used in an application */
>   #define RTE_LOGTYPE_USER1     24 /**< User-defined log type 1. */
> diff --git a/lib/memarea/memarea_private.h b/lib/memarea/memarea_private.h
> new file mode 100644
> index 0000000000..c76392d3e6
> --- /dev/null
> +++ b/lib/memarea/memarea_private.h
> @@ -0,0 +1,30 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright(c) 2022 HiSilicon Limited
> + */
> +
> +#ifndef MEMAREA_PRIVATE_H
> +#define MEMAREA_PRIVATE_H
> +
> +#include <rte_memarea.h>
> +
> +#define MEMAREA_FREE_ELEM_COOKIE	0xFFFFFFFF
> +
> +struct memarea_elem {
> +	size_t   size;
> +	uint32_t cookie;
> +	int32_t  refcnt; /* Non-zero indicates that it has been allocated */
> +	TAILQ_ENTRY(memarea_elem) elem_node;
> +	TAILQ_ENTRY(memarea_elem) free_node;
> +} __rte_cache_aligned;
> +

Why is the elem type cache line aligned? Need the elem data start be 
cache line aligned?

> +TAILQ_HEAD(memarea_elem_list, memarea_elem);
> +
> +struct rte_memarea {
> +	struct rte_memarea_param init;
> +	rte_spinlock_t           lock;
> +	void                    *area_addr;
> +	struct memarea_elem_list elem_list;
> +	struct memarea_elem_list free_list;
> +} __rte_cache_aligned;
> +
> +#endif /* MEMAREA_PRIVATE_H */
> diff --git a/lib/memarea/meson.build b/lib/memarea/meson.build
> new file mode 100644
> index 0000000000..0a74fb4cd1
> --- /dev/null
> +++ b/lib/memarea/meson.build
> @@ -0,0 +1,16 @@
> +# SPDX-License-Identifier: BSD-3-Clause
> +# Copyright(c) 2022 HiSilicon Limited
> +
> +if is_windows
> +    build = false
> +    reason = 'not supported on Windows'
> +    subdir_done()
> +endif
> +
> +sources = files(
> +        'rte_memarea.c',
> +)
> +headers = files(
> +        'rte_memarea.h',
> +)
> +deps += []
> diff --git a/lib/memarea/rte_memarea.c b/lib/memarea/rte_memarea.c
> new file mode 100644
> index 0000000000..868da7661d
> --- /dev/null
> +++ b/lib/memarea/rte_memarea.c
> @@ -0,0 +1,157 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright(c) 2022 HiSilicon Limited
> + */
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +
> +#include <rte_common.h>
> +#include <rte_log.h>
> +#include <rte_malloc.h>
> +#include <rte_spinlock.h>
> +
> +#include "rte_memarea.h"
> +#include "memarea_private.h"
> +
> +static int
> +memarea_check_param(const struct rte_memarea_param *init)
> +{
> +	size_t len;
> +
> +	if (init == NULL) {
> +		RTE_LOG(ERR, MEMAREA, "memarea init param is NULL!\n");
> +		return -EINVAL;
> +	}
> +
> +	len = strnlen(init->name, RTE_MEMAREA_NAMESIZE);
> +	if (len == 0 || len >= RTE_MEMAREA_NAMESIZE) {
> +		RTE_LOG(ERR, MEMAREA, "memarea name size %zu invalid!\n", len);
> +		return -EINVAL;
> +	}
> +
> +	if (init->source != RTE_MEMAREA_SOURCE_RTE_MEMORY &&
> +	    init->source != RTE_MEMAREA_SOURCE_SYSTEM_API &&
> +	    init->source != RTE_MEMAREA_SOURCE_USER_ADDR &&
> +	    init->source != RTE_MEMAREA_SOURCE_USER_MEMAREA) {
> +		RTE_LOG(ERR, MEMAREA, "memarea: %s source: %d not supported!\n",
> +			init->name, init->source);
> +		return -EINVAL;
> +	}
> +
> +	if (init->total_sz <= sizeof(struct memarea_elem)) {
> +		RTE_LOG(ERR, MEMAREA, "memarea: %s total-size: %zu too small!\n",
> +			init->name, init->total_sz);
> +		return -EINVAL;
> +	}
> +
> +	if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR && init->user_addr == NULL) {
> +		RTE_LOG(ERR, MEMAREA, "memarea: %s user provided addr is NULL!\n", init->name);
> +		return -EINVAL;
> +	}
> +
> +	if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR &&
> +	    ((uintptr_t)init->user_addr & (RTE_CACHE_LINE_SIZE - 1))) {
> +		RTE_LOG(ERR, MEMAREA, "memarea: %s user provided addr should align: %d!\n",
> +			init->name, RTE_CACHE_LINE_SIZE);
> +		return -EINVAL;
> +	}
> +
> +	if (init->source == RTE_MEMAREA_SOURCE_USER_MEMAREA && init->user_memarea == NULL) {
> +		RTE_LOG(ERR, MEMAREA, "memarea: %s user provided memarea is NULL!\n", init->name);
> +		return -EINVAL;
> +	}
> +
> +	if (init->alg != RTE_MEMAREA_ALG_DEFAULT) {
> +		RTE_LOG(ERR, MEMAREA, "memarea: %s alg: %d not supported!\n",
> +			init->name, init->alg);
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static void *
> +memarea_alloc_from_system_api(size_t size)
> +{
> +	void *ptr = NULL;
> +	int ret;
> +
> +	ret = posix_memalign(&ptr, RTE_CACHE_LINE_SIZE, size);
> +	if (ret)
> +		return NULL;
> +	return ptr;
> +}
> +
> +static void *
> +memarea_alloc_area(const struct rte_memarea_param *init)
> +{
> +	void *ptr = NULL;
> +
> +	if (init->source == RTE_MEMAREA_SOURCE_RTE_MEMORY)

Delete MEMORY. Of course it's memory. What else? If you want to make it 
clear it's from the RTE heap, it should spell out HEAP. Or MALLOC.

> +		ptr = rte_malloc_socket(NULL, init->total_sz, RTE_CACHE_LINE_SIZE,
> +					init->numa_socket);
> +	else if (init->source == RTE_MEMAREA_SOURCE_SYSTEM_API)
> +		ptr = memarea_alloc_from_system_api(init->total_sz);

"SYSTEM_API" doesn't strike me as a good name.

RTE_MEMAREA_SOURCE_LIBC
RTE_MEMAREA_SOURCE_STD_HEAP
or at least remove API so it'll be
RTE_MEMAREA_SOURCE_SYSTEM

> +	else if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR)

I would delete "ADDR".

> +		ptr = init->user_addr;
> +
> +	if (ptr == NULL)
> +		RTE_LOG(ERR, MEMAREA, "memarea: %s alloc memory area fail!\n", init->name);
> +
> +	return ptr;
> +}
> +
> +struct rte_memarea *
> +rte_memarea_create(const struct rte_memarea_param *init)
> +{
> +	struct memarea_elem *elem;
> +	struct rte_memarea *ma;
> +	void *addr;
> +	int ret;
> +
> +	ret = memarea_check_param(init);
> +	if (ret)
> +		return NULL;
> +
> +	addr = memarea_alloc_area(init);
> +	if (addr == NULL)
> +		return NULL;
> +
> +	ma = rte_zmalloc(NULL, sizeof(struct rte_memarea), RTE_CACHE_LINE_SIZE);
> +	if (ma == NULL) {
> +		RTE_LOG(ERR, MEMAREA, "malloc memarea: %s management obj fail!\n", init->name);
> +		return NULL;
> +	}
> +
> +	ma->init = *init;
> +	rte_spinlock_init(&ma->lock);
> +	TAILQ_INIT(&ma->elem_list);
> +	TAILQ_INIT(&ma->free_list);
> +	ma->area_addr = addr;
> +	elem = addr;
> +	elem->size = init->total_sz - sizeof(struct memarea_elem);
> +	elem->cookie = MEMAREA_FREE_ELEM_COOKIE;
> +	elem->refcnt = 0;
> +	TAILQ_INSERT_TAIL(&ma->elem_list, elem, elem_node);
> +	TAILQ_INSERT_TAIL(&ma->free_list, elem, free_node);
> +
> +	return ma;
> +}
> +
> +static void
> +memarea_free_area(struct rte_memarea *ma)
> +{
> +	if (ma->init.source == RTE_MEMAREA_SOURCE_RTE_MEMORY)
> +		rte_free(ma->area_addr);
> +	else if (ma->init.source == RTE_MEMAREA_SOURCE_SYSTEM_API)
> +		free(ma->area_addr);
> +}
> +
> +void
> +rte_memarea_destroy(struct rte_memarea *ma)
> +{
> +	if (ma == NULL)
> +		return;
> +	memarea_free_area(ma);
> +	rte_free(ma);
> +}
> diff --git a/lib/memarea/rte_memarea.h b/lib/memarea/rte_memarea.h
> new file mode 100644
> index 0000000000..543cda4cac
> --- /dev/null
> +++ b/lib/memarea/rte_memarea.h
> @@ -0,0 +1,145 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright(c) 2022 HiSilicon Limited
> + */
> +
> +#ifndef RTE_MEMAREA_H
> +#define RTE_MEMAREA_H
> +
> +/**
> + * @file
> + * RTE Memarea.
> + *
> + * The memarea is an allocator of variable-size object which based on a memory
> + * region. It has the following features:
> + *
> + * - The default alignment size is RTE_CACHE_LINE_SIZE.

This can be read as two things: the object size is aligned, or the start 
address is aligned.

> + * - The memory region can be initialized from the following memory sources:
> + *   1. RTE memory: e.g. invoke rte_malloc_socket to obtain.

Remove "to obtain", or add "memory" after "obtain". Do you really mean 
"e.g.", and not "i.e."?

> + *   2. System API: e.g. invoke posix_memalign to obtain.
> + *   3. User provided address: it can be from extended memory as long as it is
> + *      available. The address must be aligned to RTE_CACHE_LINE_SIZE.

What is extended memory?

> + *   4) User provided memarea: it can be from another memarea. So we can build
> + *      the following memory management structure:
> + *         \code{.unparsed}
> + *                           -------------
> + *                           | memarea-1 |
> + *                           -------------
> + *                                 |
> + *                                 v
> + *                  -------------------------------
> + *                  |               |             |
> + *                  v               v             v
> + *            -------------   -------------   ----------
> + *            | memarea-2 |   | memarea-3 |   | object |
> + *            -------------   -------------   ----------
> + *         \endcode
> + *      As shown above, the memarea-2/3 both create from memarea-1's memory.
> + * - It provides refcnt feature which could be useful in multi-reader scenario.
> + * - It supports MT-safe as long as it's specified at creation time. If not
> + *   specified, all the functions of the memarea API are lock-free, and assume
> + *   to not be invoked in parallel on different logical cores to work on the
> + *   same memarea.
> + */
> +
> +#include <stdbool.h>
> +#include <stdint.h>
> +#include <stdio.h>
> +
> +#include <rte_compat.h>
> +
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
> +
> +#define RTE_MEMAREA_NAMESIZE	64
> +
> +/**
> + * Memarea memory source.
> + */
> +enum rte_memarea_source {
> +	/** Memory source comes from rte memory. */
> +	RTE_MEMAREA_SOURCE_RTE_MEMORY,
> +	/** Memory source comes from system API. */
> +	RTE_MEMAREA_SOURCE_SYSTEM_API,
> +	/** Memory source comes from user-provided address. */
> +	RTE_MEMAREA_SOURCE_USER_ADDR,
> +	/** Memory source comes from user-provided memarea. */
> +	RTE_MEMAREA_SOURCE_USER_MEMAREA,
> +};
> +
> +/**
> + * Memarea memory management algorithm.
> + */
> +enum rte_memarea_alg {
> +	/* The default management algorithm is a variant of the next fit
> +	 * algorithm. It uses a free-list to apply for memory and uses an
> +	 * element-list in ascending order of address to support merging
> +	 * upon free.
> +	 */
> +	RTE_MEMAREA_ALG_DEFAULT,
> +};
> +
> +struct rte_memarea;
> +
> +struct rte_memarea_param {

Does this struct need to be public?

> +	char name[RTE_MEMAREA_NAMESIZE]; /**< Name of memarea. */
> +	enum rte_memarea_source source;  /**< Memory source of memarea. */
> +	enum rte_memarea_alg alg;        /**< Memory management algorithm. */
> +	size_t total_sz;                 /**< total size (bytes) of memarea. */
> +	/** Indicates whether the memarea API should be MT-safe. */
> +	uint32_t mt_safe : 1;

Why not bool?

> +	union {
> +		/** Numa socket from which to apply for memarea's memory, this
> +		 * field is valid only when the source is set to be
> +		 * RTE_MEMAREA_SOURCE_RTE_MEMORY.
> +		 */
> +		int numa_socket;
> +		/** User provided address, this field is valid only when the
> +		 * source is set to be RTE_MEMAREA_SOURCE_USER_ADDR.
> +		 * Note: the provided address must align at least
> +		 * RTE_CACHE_LINE_SIZE.
> +		 */
> +		void *user_addr;
> +		/** User provided memarea, this field is valid only when the
> +		 * source is set to be RTE_MEMAREA_SOURCE_USER_MEMAREA.
> +		 */
> +		struct rte_memarea *user_memarea;
> +	};
> +};
> +
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * Create memarea.
> + *
> + * Create one new memarea.
> + *
> + * @param init
> + *   The init parameter of memarea.
> + *
> + * @return
> + *   Non-NULL on success. Otherwise NULL is returned.
> + */
> +__rte_experimental
> +struct rte_memarea *rte_memarea_create(const struct rte_memarea_param *init);
> +
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * Destroy memarea.
> + *
> + * Destroy the memarea.
> + *
> + * @param ma
> + *   The pointer of memarea.
> + */
> +__rte_experimental
> +void rte_memarea_destroy(struct rte_memarea *ma);
> +
> +#ifdef __cplusplus
> +}
> +#endif
> +
> +#endif /* RTE_MEMAREA_H */
> diff --git a/lib/memarea/version.map b/lib/memarea/version.map
> new file mode 100644
> index 0000000000..f36a04d7cf
> --- /dev/null
> +++ b/lib/memarea/version.map
> @@ -0,0 +1,12 @@
> +EXPERIMENTAL {
> +	global:
> +
> +	rte_memarea_create;
> +	rte_memarea_destroy;
> +
> +	local: *;
> +};
> +
> +INTERNAL {
> +	local: *;
> +};
> diff --git a/lib/meson.build b/lib/meson.build
> index c648f7d800..521a25d6c0 100644
> --- a/lib/meson.build
> +++ b/lib/meson.build
> @@ -42,6 +42,7 @@ libraries = [
>           'kni',
>           'latencystats',
>           'lpm',
> +        'memarea',
>           'member',
>           'pcapng',
>           'power',
  
Chengwen Feng Oct. 8, 2022, 7:53 a.m. UTC | #2
Hi Mattias, Thanks for your review, most will fix in v6.

On 2022/10/7 4:15, Mattias Rönnblom wrote:
> On 2022-10-05 06:09, datshan wrote:
>> From: Chengwen Feng <fengchengwen@huawei.com>
>>
>> The memarea library is an allocator of variable-size object which based
>> on a memory region.
>>
>> This patch provides create/destroy API.
>>
>> Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
>> ---
>>   MAINTAINERS                            |   5 +
>>   doc/api/doxy-api-index.md              |   3 +-
>>   doc/api/doxy-api.conf.in               |   1 +
>>   doc/guides/prog_guide/index.rst        |   1 +
>>   doc/guides/prog_guide/memarea_lib.rst  |  39 ++++++
>>   doc/guides/rel_notes/release_22_11.rst |   6 +
>>   lib/eal/common/eal_common_log.c        |   1 +
>>   lib/eal/include/rte_log.h              |   1 +
>>   lib/memarea/memarea_private.h          |  30 +++++
>>   lib/memarea/meson.build                |  16 +++
>>   lib/memarea/rte_memarea.c              | 157 +++++++++++++++++++++++++
>>   lib/memarea/rte_memarea.h              | 145 +++++++++++++++++++++++
>>   lib/memarea/version.map                |  12 ++
>>   lib/meson.build                        |   1 +
>>   14 files changed, 417 insertions(+), 1 deletion(-)
>>   create mode 100644 doc/guides/prog_guide/memarea_lib.rst
>>   create mode 100644 lib/memarea/memarea_private.h
>>   create mode 100644 lib/memarea/meson.build
>>   create mode 100644 lib/memarea/rte_memarea.c
>>   create mode 100644 lib/memarea/rte_memarea.h
>>   create mode 100644 lib/memarea/version.map
>>
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index a55b379d73..b9c638221d 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -1550,6 +1550,11 @@ F: app/test/test_lpm*
>>   F: app/test/test_func_reentrancy.c
>>   F: app/test/test_xmmt_ops.h
>>   +Memarea - EXPERIMENTAL
>> +M: Chengwen Feng <fengchengwen@huawei.com>
>> +F: lib/memarea
>> +F: doc/guides/prog_guide/memarea_lib.rst
>> +
>>   Membership - EXPERIMENTAL
>>   M: Yipeng Wang <yipeng1.wang@intel.com>
>>   M: Sameh Gobriel <sameh.gobriel@intel.com>
>> diff --git a/doc/api/doxy-api-index.md b/doc/api/doxy-api-index.md
>> index de488c7abf..24456604f8 100644
>> --- a/doc/api/doxy-api-index.md
>> +++ b/doc/api/doxy-api-index.md
>> @@ -62,7 +62,8 @@ The public API headers are grouped by topics:
>>     [memzone](@ref rte_memzone.h),
>>     [mempool](@ref rte_mempool.h),
>>     [malloc](@ref rte_malloc.h),
>> -  [memcpy](@ref rte_memcpy.h)
>> +  [memcpy](@ref rte_memcpy.h),
>> +  [memarea](@ref rte_memarea.h)
>>     - **timers**:
>>     [cycles](@ref rte_cycles.h),
>> diff --git a/doc/api/doxy-api.conf.in b/doc/api/doxy-api.conf.in
>> index f0886c3bd1..8334ebcbd6 100644
>> --- a/doc/api/doxy-api.conf.in
>> +++ b/doc/api/doxy-api.conf.in
>> @@ -53,6 +53,7 @@ INPUT                   = @TOPDIR@/doc/api/doxy-api-index.md \
>>                             @TOPDIR@/lib/latencystats \
>>                             @TOPDIR@/lib/lpm \
>>                             @TOPDIR@/lib/mbuf \
>> +                          @TOPDIR@/lib/memarea \
>>                             @TOPDIR@/lib/member \
>>                             @TOPDIR@/lib/mempool \
>>                             @TOPDIR@/lib/meter \
>> diff --git a/doc/guides/prog_guide/index.rst b/doc/guides/prog_guide/index.rst
>> index 8564883018..e9015d65e3 100644
>> --- a/doc/guides/prog_guide/index.rst
>> +++ b/doc/guides/prog_guide/index.rst
>> @@ -37,6 +37,7 @@ Programmer's Guide
>>       hash_lib
>>       toeplitz_hash_lib
>>       efd_lib
>> +    memarea_lib
>>       member_lib
>>       lpm_lib
>>       lpm6_lib
>> diff --git a/doc/guides/prog_guide/memarea_lib.rst b/doc/guides/prog_guide/memarea_lib.rst
>> new file mode 100644
>> index 0000000000..b96dad15f6
>> --- /dev/null
>> +++ b/doc/guides/prog_guide/memarea_lib.rst
>> @@ -0,0 +1,39 @@
>> +..  SPDX-License-Identifier: BSD-3-Clause
>> +    Copyright(c) 2022 HiSilicon Limited
>> +
>> +Memarea Library
>> +===============
>> +
>> +Introduction
>> +------------
>> +
>> +The memarea library provides an allocator of variable-size objects, it is
>> +oriented towards the application layer, which could provides 'region-based
>> +memory management' function [1].
>> +
>> +The main features are as follows:
>> +
>> +* The default aligement size is ``RTE_CACHE_LINE_SIZE``.
>> +
>> +* The memory region can be initialized from the following memory sources:
>> +  a) RTE memory: e.g. invoke ``rte_malloc_socket`` to obtain. b) System API:
>> +  e.g. invoke posix_memalign to obtain. c) User provided address: it can be from
>> +  extendedd memory as long as it is available. d) User provided memarea: it can
>> +  be from another memarea.
>> +
>> +* It provides refcnt feature which could be useful in multi-reader scenario.
>> +
>> +* It supports MT-safe as long as it's specified at creation time.
>> +
>> +Library API Overview
>> +--------------------
>> +
>> +The ``rte_memarea_create()`` function is used to create a memarea, the function
>> +returns the pointer to the created memarea or ``NULL`` if the creation failed.
>> +
>> +The ``rte_memarea_destroy()`` function is used to destroy a memarea.
>> +
>> +Reference
>> +---------
>> +
>> +[1] https://en.wikipedia.org/wiki/Region-based_memory_management
>> diff --git a/doc/guides/rel_notes/release_22_11.rst b/doc/guides/rel_notes/release_22_11.rst
>> index 5d8ef669b8..4c1f760b98 100644
>> --- a/doc/guides/rel_notes/release_22_11.rst
>> +++ b/doc/guides/rel_notes/release_22_11.rst
>> @@ -55,6 +55,12 @@ New Features
>>        Also, make sure to start the actual text at the margin.
>>        =======================================================
>>   +* **Added memarea library.**
>> +
>> +  The memarea library is an allocator of variable-size objects, it is oriented
>> +  towards the application layer, which could provides 'region-based memory
>> +  management' function.
>> +
>>   * **Added configuration for asynchronous flow connection tracking.**
>>       Added connection tracking action number hint to ``rte_flow_configure``
>> diff --git a/lib/eal/common/eal_common_log.c b/lib/eal/common/eal_common_log.c
>> index bd7b188ceb..3d62af59c6 100644
>> --- a/lib/eal/common/eal_common_log.c
>> +++ b/lib/eal/common/eal_common_log.c
>> @@ -369,6 +369,7 @@ static const struct logtype logtype_strings[] = {
>>       {RTE_LOGTYPE_EFD,        "lib.efd"},
>>       {RTE_LOGTYPE_EVENTDEV,   "lib.eventdev"},
>>       {RTE_LOGTYPE_GSO,        "lib.gso"},
>> +    {RTE_LOGTYPE_MEMAREA,    "lib.memarea"},
>>       {RTE_LOGTYPE_USER1,      "user1"},
>>       {RTE_LOGTYPE_USER2,      "user2"},
>>       {RTE_LOGTYPE_USER3,      "user3"},
>> diff --git a/lib/eal/include/rte_log.h b/lib/eal/include/rte_log.h
>> index 25ce42cdfc..708f3a39dd 100644
>> --- a/lib/eal/include/rte_log.h
>> +++ b/lib/eal/include/rte_log.h
>> @@ -48,6 +48,7 @@ extern "C" {
>>   #define RTE_LOGTYPE_EFD       18 /**< Log related to EFD. */
>>   #define RTE_LOGTYPE_EVENTDEV  19 /**< Log related to eventdev. */
>>   #define RTE_LOGTYPE_GSO       20 /**< Log related to GSO. */
>> +#define RTE_LOGTYPE_MEMAREA   21 /**< Log related to memarea. */
>>     /* these log types can be used in an application */
>>   #define RTE_LOGTYPE_USER1     24 /**< User-defined log type 1. */
>> diff --git a/lib/memarea/memarea_private.h b/lib/memarea/memarea_private.h
>> new file mode 100644
>> index 0000000000..c76392d3e6
>> --- /dev/null
>> +++ b/lib/memarea/memarea_private.h
>> @@ -0,0 +1,30 @@
>> +/* SPDX-License-Identifier: BSD-3-Clause
>> + * Copyright(c) 2022 HiSilicon Limited
>> + */
>> +
>> +#ifndef MEMAREA_PRIVATE_H
>> +#define MEMAREA_PRIVATE_H
>> +
>> +#include <rte_memarea.h>
>> +
>> +#define MEMAREA_FREE_ELEM_COOKIE    0xFFFFFFFF
>> +
>> +struct memarea_elem {
>> +    size_t   size;
>> +    uint32_t cookie;
>> +    int32_t  refcnt; /* Non-zero indicates that it has been allocated */
>> +    TAILQ_ENTRY(memarea_elem) elem_node;
>> +    TAILQ_ENTRY(memarea_elem) free_node;
>> +} __rte_cache_aligned;
>> +
> 
> Why is the elem type cache line aligned? Need the elem data start be cache line aligned?

Yes, the elem data align at cache-line default.

> 
>> +TAILQ_HEAD(memarea_elem_list, memarea_elem);
>> +
>> +struct rte_memarea {
>> +    struct rte_memarea_param init;
>> +    rte_spinlock_t           lock;
>> +    void                    *area_addr;
>> +    struct memarea_elem_list elem_list;
>> +    struct memarea_elem_list free_list;
>> +} __rte_cache_aligned;
>> +
>> +#endif /* MEMAREA_PRIVATE_H */
>> diff --git a/lib/memarea/meson.build b/lib/memarea/meson.build
>> new file mode 100644
>> index 0000000000..0a74fb4cd1
>> --- /dev/null
>> +++ b/lib/memarea/meson.build
>> @@ -0,0 +1,16 @@
>> +# SPDX-License-Identifier: BSD-3-Clause
>> +# Copyright(c) 2022 HiSilicon Limited
>> +
>> +if is_windows
>> +    build = false
>> +    reason = 'not supported on Windows'
>> +    subdir_done()
>> +endif
>> +
>> +sources = files(
>> +        'rte_memarea.c',
>> +)
>> +headers = files(
>> +        'rte_memarea.h',
>> +)
>> +deps += []
>> diff --git a/lib/memarea/rte_memarea.c b/lib/memarea/rte_memarea.c
>> new file mode 100644
>> index 0000000000..868da7661d
>> --- /dev/null
>> +++ b/lib/memarea/rte_memarea.c
>> @@ -0,0 +1,157 @@
>> +/* SPDX-License-Identifier: BSD-3-Clause
>> + * Copyright(c) 2022 HiSilicon Limited
>> + */
>> +
>> +#include <stdio.h>
>> +#include <stdlib.h>
>> +
>> +#include <rte_common.h>
>> +#include <rte_log.h>
>> +#include <rte_malloc.h>
>> +#include <rte_spinlock.h>
>> +
>> +#include "rte_memarea.h"
>> +#include "memarea_private.h"
>> +
>> +static int
>> +memarea_check_param(const struct rte_memarea_param *init)
>> +{
>> +    size_t len;
>> +
>> +    if (init == NULL) {
>> +        RTE_LOG(ERR, MEMAREA, "memarea init param is NULL!\n");
>> +        return -EINVAL;
>> +    }
>> +
>> +    len = strnlen(init->name, RTE_MEMAREA_NAMESIZE);
>> +    if (len == 0 || len >= RTE_MEMAREA_NAMESIZE) {
>> +        RTE_LOG(ERR, MEMAREA, "memarea name size %zu invalid!\n", len);
>> +        return -EINVAL;
>> +    }
>> +
>> +    if (init->source != RTE_MEMAREA_SOURCE_RTE_MEMORY &&
>> +        init->source != RTE_MEMAREA_SOURCE_SYSTEM_API &&
>> +        init->source != RTE_MEMAREA_SOURCE_USER_ADDR &&
>> +        init->source != RTE_MEMAREA_SOURCE_USER_MEMAREA) {
>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s source: %d not supported!\n",
>> +            init->name, init->source);
>> +        return -EINVAL;
>> +    }
>> +
>> +    if (init->total_sz <= sizeof(struct memarea_elem)) {
>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s total-size: %zu too small!\n",
>> +            init->name, init->total_sz);
>> +        return -EINVAL;
>> +    }
>> +
>> +    if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR && init->user_addr == NULL) {
>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s user provided addr is NULL!\n", init->name);
>> +        return -EINVAL;
>> +    }
>> +
>> +    if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR &&
>> +        ((uintptr_t)init->user_addr & (RTE_CACHE_LINE_SIZE - 1))) {
>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s user provided addr should align: %d!\n",
>> +            init->name, RTE_CACHE_LINE_SIZE);
>> +        return -EINVAL;
>> +    }
>> +
>> +    if (init->source == RTE_MEMAREA_SOURCE_USER_MEMAREA && init->user_memarea == NULL) {
>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s user provided memarea is NULL!\n", init->name);
>> +        return -EINVAL;
>> +    }
>> +
>> +    if (init->alg != RTE_MEMAREA_ALG_DEFAULT) {
>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s alg: %d not supported!\n",
>> +            init->name, init->alg);
>> +        return -EINVAL;
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static void *
>> +memarea_alloc_from_system_api(size_t size)
>> +{
>> +    void *ptr = NULL;
>> +    int ret;
>> +
>> +    ret = posix_memalign(&ptr, RTE_CACHE_LINE_SIZE, size);
>> +    if (ret)
>> +        return NULL;
>> +    return ptr;
>> +}
>> +
>> +static void *
>> +memarea_alloc_area(const struct rte_memarea_param *init)
>> +{
>> +    void *ptr = NULL;
>> +
>> +    if (init->source == RTE_MEMAREA_SOURCE_RTE_MEMORY)
> 
> Delete MEMORY. Of course it's memory. What else? If you want to make it clear it's from the RTE heap, it should spell out HEAP. Or MALLOC.

HEAP seem better.

> 
>> +        ptr = rte_malloc_socket(NULL, init->total_sz, RTE_CACHE_LINE_SIZE,
>> +                    init->numa_socket);
>> +    else if (init->source == RTE_MEMAREA_SOURCE_SYSTEM_API)
>> +        ptr = memarea_alloc_from_system_api(init->total_sz);
> 
> "SYSTEM_API" doesn't strike me as a good name.
> 
> RTE_MEMAREA_SOURCE_LIBC

LIBC seem better.

> RTE_MEMAREA_SOURCE_STD_HEAP
> or at least remove API so it'll be
> RTE_MEMAREA_SOURCE_SYSTEM
> 
>> +    else if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR)
> 
> I would delete "ADDR".

+1

> 
>> +        ptr = init->user_addr;
>> +
>> +    if (ptr == NULL)
>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s alloc memory area fail!\n", init->name);
>> +
>> +    return ptr;
>> +}
>> +
>> +struct rte_memarea *
>> +rte_memarea_create(const struct rte_memarea_param *init)
>> +{
>> +    struct memarea_elem *elem;
>> +    struct rte_memarea *ma;
>> +    void *addr;
>> +    int ret;
>> +
>> +    ret = memarea_check_param(init);
>> +    if (ret)
>> +        return NULL;
>> +
>> +    addr = memarea_alloc_area(init);
>> +    if (addr == NULL)
>> +        return NULL;
>> +
>> +    ma = rte_zmalloc(NULL, sizeof(struct rte_memarea), RTE_CACHE_LINE_SIZE);
>> +    if (ma == NULL) {
>> +        RTE_LOG(ERR, MEMAREA, "malloc memarea: %s management obj fail!\n", init->name);
>> +        return NULL;
>> +    }
>> +
>> +    ma->init = *init;
>> +    rte_spinlock_init(&ma->lock);
>> +    TAILQ_INIT(&ma->elem_list);
>> +    TAILQ_INIT(&ma->free_list);
>> +    ma->area_addr = addr;
>> +    elem = addr;
>> +    elem->size = init->total_sz - sizeof(struct memarea_elem);
>> +    elem->cookie = MEMAREA_FREE_ELEM_COOKIE;
>> +    elem->refcnt = 0;
>> +    TAILQ_INSERT_TAIL(&ma->elem_list, elem, elem_node);
>> +    TAILQ_INSERT_TAIL(&ma->free_list, elem, free_node);
>> +
>> +    return ma;
>> +}
>> +
>> +static void
>> +memarea_free_area(struct rte_memarea *ma)
>> +{
>> +    if (ma->init.source == RTE_MEMAREA_SOURCE_RTE_MEMORY)
>> +        rte_free(ma->area_addr);
>> +    else if (ma->init.source == RTE_MEMAREA_SOURCE_SYSTEM_API)
>> +        free(ma->area_addr);
>> +}
>> +
>> +void
>> +rte_memarea_destroy(struct rte_memarea *ma)
>> +{
>> +    if (ma == NULL)
>> +        return;
>> +    memarea_free_area(ma);
>> +    rte_free(ma);
>> +}
>> diff --git a/lib/memarea/rte_memarea.h b/lib/memarea/rte_memarea.h
>> new file mode 100644
>> index 0000000000..543cda4cac
>> --- /dev/null
>> +++ b/lib/memarea/rte_memarea.h
>> @@ -0,0 +1,145 @@
>> +/* SPDX-License-Identifier: BSD-3-Clause
>> + * Copyright(c) 2022 HiSilicon Limited
>> + */
>> +
>> +#ifndef RTE_MEMAREA_H
>> +#define RTE_MEMAREA_H
>> +
>> +/**
>> + * @file
>> + * RTE Memarea.
>> + *
>> + * The memarea is an allocator of variable-size object which based on a memory
>> + * region. It has the following features:
>> + *
>> + * - The default alignment size is RTE_CACHE_LINE_SIZE.
> 
> This can be read as two things: the object size is aligned, or the start address is aligned.

It means the start address align, will define more clear in v6.

> 
>> + * - The memory region can be initialized from the following memory sources:
>> + *   1. RTE memory: e.g. invoke rte_malloc_socket to obtain.
> 
> Remove "to obtain", or add "memory" after "obtain". Do you really mean "e.g.", and not "i.e."?

will fix in v6.

> 
>> + *   2. System API: e.g. invoke posix_memalign to obtain.
>> + *   3. User provided address: it can be from extended memory as long as it is
>> + *      available. The address must be aligned to RTE_CACHE_LINE_SIZE.
> 
> What is extended memory?

Like rte_extmen

> 
>> + *   4) User provided memarea: it can be from another memarea. So we can build
>> + *      the following memory management structure:
>> + *         \code{.unparsed}
>> + *                           -------------
>> + *                           | memarea-1 |
>> + *                           -------------
>> + *                                 |
>> + *                                 v
>> + *                  -------------------------------
>> + *                  |               |             |
>> + *                  v               v             v
>> + *            -------------   -------------   ----------
>> + *            | memarea-2 |   | memarea-3 |   | object |
>> + *            -------------   -------------   ----------
>> + *         \endcode
>> + *      As shown above, the memarea-2/3 both create from memarea-1's memory.
>> + * - It provides refcnt feature which could be useful in multi-reader scenario.
>> + * - It supports MT-safe as long as it's specified at creation time. If not
>> + *   specified, all the functions of the memarea API are lock-free, and assume
>> + *   to not be invoked in parallel on different logical cores to work on the
>> + *   same memarea.
>> + */
>> +
>> +#include <stdbool.h>
>> +#include <stdint.h>
>> +#include <stdio.h>
>> +
>> +#include <rte_compat.h>
>> +
>> +#ifdef __cplusplus
>> +extern "C" {
>> +#endif
>> +
>> +#define RTE_MEMAREA_NAMESIZE    64
>> +
>> +/**
>> + * Memarea memory source.
>> + */
>> +enum rte_memarea_source {
>> +    /** Memory source comes from rte memory. */
>> +    RTE_MEMAREA_SOURCE_RTE_MEMORY,
>> +    /** Memory source comes from system API. */
>> +    RTE_MEMAREA_SOURCE_SYSTEM_API,
>> +    /** Memory source comes from user-provided address. */
>> +    RTE_MEMAREA_SOURCE_USER_ADDR,
>> +    /** Memory source comes from user-provided memarea. */
>> +    RTE_MEMAREA_SOURCE_USER_MEMAREA,
>> +};
>> +
>> +/**
>> + * Memarea memory management algorithm.
>> + */
>> +enum rte_memarea_alg {
>> +    /* The default management algorithm is a variant of the next fit
>> +     * algorithm. It uses a free-list to apply for memory and uses an
>> +     * element-list in ascending order of address to support merging
>> +     * upon free.
>> +     */
>> +    RTE_MEMAREA_ALG_DEFAULT,
>> +};
>> +
>> +struct rte_memarea;
>> +
>> +struct rte_memarea_param {
> 
> Does this struct need to be public?

Yes, the rte_memarea_param contains create parameters for create memarea which need be public.

And rte_memarea which pointer implementation struction which just a declare here.

> 
>> +    char name[RTE_MEMAREA_NAMESIZE]; /**< Name of memarea. */
>> +    enum rte_memarea_source source;  /**< Memory source of memarea. */
>> +    enum rte_memarea_alg alg;        /**< Memory management algorithm. */
>> +    size_t total_sz;                 /**< total size (bytes) of memarea. */
>> +    /** Indicates whether the memarea API should be MT-safe. */
>> +    uint32_t mt_safe : 1;
> 
> Why not bool?

Use bit field other than bool will provides more reserved field.

> 
>> +    union {
>> +        /** Numa socket from which to apply for memarea's memory, this
>> +         * field is valid only when the source is set to be
>> +         * RTE_MEMAREA_SOURCE_RTE_MEMORY.
>> +         */
>> +        int numa_socket;
>> +        /** User provided address, this field is valid only when the
>> +         * source is set to be RTE_MEMAREA_SOURCE_USER_ADDR.
>> +         * Note: the provided address must align at least
>> +         * RTE_CACHE_LINE_SIZE.
>> +         */
>> +        void *user_addr;
>> +        /** User provided memarea, this field is valid only when the
>> +         * source is set to be RTE_MEMAREA_SOURCE_USER_MEMAREA.
>> +         */
>> +        struct rte_memarea *user_memarea;
>> +    };
>> +};
>> +
>> +/**
>> + * @warning
>> + * @b EXPERIMENTAL: this API may change without prior notice.
>> + *
>> + * Create memarea.
>> + *
>> + * Create one new memarea.
>> + *
>> + * @param init
>> + *   The init parameter of memarea.
>> + *
>> + * @return
>> + *   Non-NULL on success. Otherwise NULL is returned.
>> + */
>> +__rte_experimental
>> +struct rte_memarea *rte_memarea_create(const struct rte_memarea_param *init);
>> +
>> +/**
>> + * @warning
>> + * @b EXPERIMENTAL: this API may change without prior notice.
>> + *
>> + * Destroy memarea.
>> + *
>> + * Destroy the memarea.
>> + *
>> + * @param ma
>> + *   The pointer of memarea.
>> + */
>> +__rte_experimental
>> +void rte_memarea_destroy(struct rte_memarea *ma);
>> +
>> +#ifdef __cplusplus
>> +}
>> +#endif
>> +
>> +#endif /* RTE_MEMAREA_H */
>> diff --git a/lib/memarea/version.map b/lib/memarea/version.map
>> new file mode 100644
>> index 0000000000..f36a04d7cf
>> --- /dev/null
>> +++ b/lib/memarea/version.map
>> @@ -0,0 +1,12 @@
>> +EXPERIMENTAL {
>> +    global:
>> +
>> +    rte_memarea_create;
>> +    rte_memarea_destroy;
>> +
>> +    local: *;
>> +};
>> +
>> +INTERNAL {
>> +    local: *;
>> +};
>> diff --git a/lib/meson.build b/lib/meson.build
>> index c648f7d800..521a25d6c0 100644
>> --- a/lib/meson.build
>> +++ b/lib/meson.build
>> @@ -42,6 +42,7 @@ libraries = [
>>           'kni',
>>           'latencystats',
>>           'lpm',
>> +        'memarea',
>>           'member',
>>           'pcapng',
>>           'power',
> 
> .
  
Mattias Rönnblom Oct. 10, 2022, 4:53 p.m. UTC | #3
On 2022-10-08 09:53, fengchengwen wrote:
> Hi Mattias, Thanks for your review, most will fix in v6.
> 
> On 2022/10/7 4:15, Mattias Rönnblom wrote:
>> On 2022-10-05 06:09, datshan wrote:
>>> From: Chengwen Feng <fengchengwen@huawei.com>
>>>
>>> The memarea library is an allocator of variable-size object which based
>>> on a memory region.
>>>
>>> This patch provides create/destroy API.
>>>
>>> Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
>>> ---
>>>    MAINTAINERS                            |   5 +
>>>    doc/api/doxy-api-index.md              |   3 +-
>>>    doc/api/doxy-api.conf.in               |   1 +
>>>    doc/guides/prog_guide/index.rst        |   1 +
>>>    doc/guides/prog_guide/memarea_lib.rst  |  39 ++++++
>>>    doc/guides/rel_notes/release_22_11.rst |   6 +
>>>    lib/eal/common/eal_common_log.c        |   1 +
>>>    lib/eal/include/rte_log.h              |   1 +
>>>    lib/memarea/memarea_private.h          |  30 +++++
>>>    lib/memarea/meson.build                |  16 +++
>>>    lib/memarea/rte_memarea.c              | 157 +++++++++++++++++++++++++
>>>    lib/memarea/rte_memarea.h              | 145 +++++++++++++++++++++++
>>>    lib/memarea/version.map                |  12 ++
>>>    lib/meson.build                        |   1 +
>>>    14 files changed, 417 insertions(+), 1 deletion(-)
>>>    create mode 100644 doc/guides/prog_guide/memarea_lib.rst
>>>    create mode 100644 lib/memarea/memarea_private.h
>>>    create mode 100644 lib/memarea/meson.build
>>>    create mode 100644 lib/memarea/rte_memarea.c
>>>    create mode 100644 lib/memarea/rte_memarea.h
>>>    create mode 100644 lib/memarea/version.map
>>>
>>> diff --git a/MAINTAINERS b/MAINTAINERS
>>> index a55b379d73..b9c638221d 100644
>>> --- a/MAINTAINERS
>>> +++ b/MAINTAINERS
>>> @@ -1550,6 +1550,11 @@ F: app/test/test_lpm*
>>>    F: app/test/test_func_reentrancy.c
>>>    F: app/test/test_xmmt_ops.h
>>>    +Memarea - EXPERIMENTAL
>>> +M: Chengwen Feng <fengchengwen@huawei.com>
>>> +F: lib/memarea
>>> +F: doc/guides/prog_guide/memarea_lib.rst
>>> +
>>>    Membership - EXPERIMENTAL
>>>    M: Yipeng Wang <yipeng1.wang@intel.com>
>>>    M: Sameh Gobriel <sameh.gobriel@intel.com>
>>> diff --git a/doc/api/doxy-api-index.md b/doc/api/doxy-api-index.md
>>> index de488c7abf..24456604f8 100644
>>> --- a/doc/api/doxy-api-index.md
>>> +++ b/doc/api/doxy-api-index.md
>>> @@ -62,7 +62,8 @@ The public API headers are grouped by topics:
>>>      [memzone](@ref rte_memzone.h),
>>>      [mempool](@ref rte_mempool.h),
>>>      [malloc](@ref rte_malloc.h),
>>> -  [memcpy](@ref rte_memcpy.h)
>>> +  [memcpy](@ref rte_memcpy.h),
>>> +  [memarea](@ref rte_memarea.h)
>>>      - **timers**:
>>>      [cycles](@ref rte_cycles.h),
>>> diff --git a/doc/api/doxy-api.conf.in b/doc/api/doxy-api.conf.in
>>> index f0886c3bd1..8334ebcbd6 100644
>>> --- a/doc/api/doxy-api.conf.in
>>> +++ b/doc/api/doxy-api.conf.in
>>> @@ -53,6 +53,7 @@ INPUT                   = @TOPDIR@/doc/api/doxy-api-index.md \
>>>                              @TOPDIR@/lib/latencystats \
>>>                              @TOPDIR@/lib/lpm \
>>>                              @TOPDIR@/lib/mbuf \
>>> +                          @TOPDIR@/lib/memarea \
>>>                              @TOPDIR@/lib/member \
>>>                              @TOPDIR@/lib/mempool \
>>>                              @TOPDIR@/lib/meter \
>>> diff --git a/doc/guides/prog_guide/index.rst b/doc/guides/prog_guide/index.rst
>>> index 8564883018..e9015d65e3 100644
>>> --- a/doc/guides/prog_guide/index.rst
>>> +++ b/doc/guides/prog_guide/index.rst
>>> @@ -37,6 +37,7 @@ Programmer's Guide
>>>        hash_lib
>>>        toeplitz_hash_lib
>>>        efd_lib
>>> +    memarea_lib
>>>        member_lib
>>>        lpm_lib
>>>        lpm6_lib
>>> diff --git a/doc/guides/prog_guide/memarea_lib.rst b/doc/guides/prog_guide/memarea_lib.rst
>>> new file mode 100644
>>> index 0000000000..b96dad15f6
>>> --- /dev/null
>>> +++ b/doc/guides/prog_guide/memarea_lib.rst
>>> @@ -0,0 +1,39 @@
>>> +..  SPDX-License-Identifier: BSD-3-Clause
>>> +    Copyright(c) 2022 HiSilicon Limited
>>> +
>>> +Memarea Library
>>> +===============
>>> +
>>> +Introduction
>>> +------------
>>> +
>>> +The memarea library provides an allocator of variable-size objects, it is
>>> +oriented towards the application layer, which could provides 'region-based
>>> +memory management' function [1].
>>> +
>>> +The main features are as follows:
>>> +
>>> +* The default aligement size is ``RTE_CACHE_LINE_SIZE``.
>>> +
>>> +* The memory region can be initialized from the following memory sources:
>>> +  a) RTE memory: e.g. invoke ``rte_malloc_socket`` to obtain. b) System API:
>>> +  e.g. invoke posix_memalign to obtain. c) User provided address: it can be from
>>> +  extendedd memory as long as it is available. d) User provided memarea: it can
>>> +  be from another memarea.
>>> +
>>> +* It provides refcnt feature which could be useful in multi-reader scenario.
>>> +
>>> +* It supports MT-safe as long as it's specified at creation time.
>>> +
>>> +Library API Overview
>>> +--------------------
>>> +
>>> +The ``rte_memarea_create()`` function is used to create a memarea, the function
>>> +returns the pointer to the created memarea or ``NULL`` if the creation failed.
>>> +
>>> +The ``rte_memarea_destroy()`` function is used to destroy a memarea.
>>> +
>>> +Reference
>>> +---------
>>> +
>>> +[1] https://en.wikipedia.org/wiki/Region-based_memory_management
>>> diff --git a/doc/guides/rel_notes/release_22_11.rst b/doc/guides/rel_notes/release_22_11.rst
>>> index 5d8ef669b8..4c1f760b98 100644
>>> --- a/doc/guides/rel_notes/release_22_11.rst
>>> +++ b/doc/guides/rel_notes/release_22_11.rst
>>> @@ -55,6 +55,12 @@ New Features
>>>         Also, make sure to start the actual text at the margin.
>>>         =======================================================
>>>    +* **Added memarea library.**
>>> +
>>> +  The memarea library is an allocator of variable-size objects, it is oriented
>>> +  towards the application layer, which could provides 'region-based memory
>>> +  management' function.
>>> +
>>>    * **Added configuration for asynchronous flow connection tracking.**
>>>        Added connection tracking action number hint to ``rte_flow_configure``
>>> diff --git a/lib/eal/common/eal_common_log.c b/lib/eal/common/eal_common_log.c
>>> index bd7b188ceb..3d62af59c6 100644
>>> --- a/lib/eal/common/eal_common_log.c
>>> +++ b/lib/eal/common/eal_common_log.c
>>> @@ -369,6 +369,7 @@ static const struct logtype logtype_strings[] = {
>>>        {RTE_LOGTYPE_EFD,        "lib.efd"},
>>>        {RTE_LOGTYPE_EVENTDEV,   "lib.eventdev"},
>>>        {RTE_LOGTYPE_GSO,        "lib.gso"},
>>> +    {RTE_LOGTYPE_MEMAREA,    "lib.memarea"},
>>>        {RTE_LOGTYPE_USER1,      "user1"},
>>>        {RTE_LOGTYPE_USER2,      "user2"},
>>>        {RTE_LOGTYPE_USER3,      "user3"},
>>> diff --git a/lib/eal/include/rte_log.h b/lib/eal/include/rte_log.h
>>> index 25ce42cdfc..708f3a39dd 100644
>>> --- a/lib/eal/include/rte_log.h
>>> +++ b/lib/eal/include/rte_log.h
>>> @@ -48,6 +48,7 @@ extern "C" {
>>>    #define RTE_LOGTYPE_EFD       18 /**< Log related to EFD. */
>>>    #define RTE_LOGTYPE_EVENTDEV  19 /**< Log related to eventdev. */
>>>    #define RTE_LOGTYPE_GSO       20 /**< Log related to GSO. */
>>> +#define RTE_LOGTYPE_MEMAREA   21 /**< Log related to memarea. */
>>>      /* these log types can be used in an application */
>>>    #define RTE_LOGTYPE_USER1     24 /**< User-defined log type 1. */
>>> diff --git a/lib/memarea/memarea_private.h b/lib/memarea/memarea_private.h
>>> new file mode 100644
>>> index 0000000000..c76392d3e6
>>> --- /dev/null
>>> +++ b/lib/memarea/memarea_private.h
>>> @@ -0,0 +1,30 @@
>>> +/* SPDX-License-Identifier: BSD-3-Clause
>>> + * Copyright(c) 2022 HiSilicon Limited
>>> + */
>>> +
>>> +#ifndef MEMAREA_PRIVATE_H
>>> +#define MEMAREA_PRIVATE_H
>>> +
>>> +#include <rte_memarea.h>
>>> +
>>> +#define MEMAREA_FREE_ELEM_COOKIE    0xFFFFFFFF
>>> +
>>> +struct memarea_elem {
>>> +    size_t   size;
>>> +    uint32_t cookie;
>>> +    int32_t  refcnt; /* Non-zero indicates that it has been allocated */
>>> +    TAILQ_ENTRY(memarea_elem) elem_node;
>>> +    TAILQ_ENTRY(memarea_elem) free_node;
>>> +} __rte_cache_aligned;
>>> +
>>
>> Why is the elem type cache line aligned? Need the elem data start be cache line aligned?
> 
> Yes, the elem data align at cache-line default.
> 
>>
>>> +TAILQ_HEAD(memarea_elem_list, memarea_elem);
>>> +
>>> +struct rte_memarea {
>>> +    struct rte_memarea_param init;
>>> +    rte_spinlock_t           lock;
>>> +    void                    *area_addr;
>>> +    struct memarea_elem_list elem_list;
>>> +    struct memarea_elem_list free_list;
>>> +} __rte_cache_aligned;
>>> +
>>> +#endif /* MEMAREA_PRIVATE_H */
>>> diff --git a/lib/memarea/meson.build b/lib/memarea/meson.build
>>> new file mode 100644
>>> index 0000000000..0a74fb4cd1
>>> --- /dev/null
>>> +++ b/lib/memarea/meson.build
>>> @@ -0,0 +1,16 @@
>>> +# SPDX-License-Identifier: BSD-3-Clause
>>> +# Copyright(c) 2022 HiSilicon Limited
>>> +
>>> +if is_windows
>>> +    build = false
>>> +    reason = 'not supported on Windows'
>>> +    subdir_done()
>>> +endif
>>> +
>>> +sources = files(
>>> +        'rte_memarea.c',
>>> +)
>>> +headers = files(
>>> +        'rte_memarea.h',
>>> +)
>>> +deps += []
>>> diff --git a/lib/memarea/rte_memarea.c b/lib/memarea/rte_memarea.c
>>> new file mode 100644
>>> index 0000000000..868da7661d
>>> --- /dev/null
>>> +++ b/lib/memarea/rte_memarea.c
>>> @@ -0,0 +1,157 @@
>>> +/* SPDX-License-Identifier: BSD-3-Clause
>>> + * Copyright(c) 2022 HiSilicon Limited
>>> + */
>>> +
>>> +#include <stdio.h>
>>> +#include <stdlib.h>
>>> +
>>> +#include <rte_common.h>
>>> +#include <rte_log.h>
>>> +#include <rte_malloc.h>
>>> +#include <rte_spinlock.h>
>>> +
>>> +#include "rte_memarea.h"
>>> +#include "memarea_private.h"
>>> +
>>> +static int
>>> +memarea_check_param(const struct rte_memarea_param *init)
>>> +{
>>> +    size_t len;
>>> +
>>> +    if (init == NULL) {
>>> +        RTE_LOG(ERR, MEMAREA, "memarea init param is NULL!\n");
>>> +        return -EINVAL;
>>> +    }
>>> +
>>> +    len = strnlen(init->name, RTE_MEMAREA_NAMESIZE);
>>> +    if (len == 0 || len >= RTE_MEMAREA_NAMESIZE) {
>>> +        RTE_LOG(ERR, MEMAREA, "memarea name size %zu invalid!\n", len);
>>> +        return -EINVAL;
>>> +    }
>>> +
>>> +    if (init->source != RTE_MEMAREA_SOURCE_RTE_MEMORY &&
>>> +        init->source != RTE_MEMAREA_SOURCE_SYSTEM_API &&
>>> +        init->source != RTE_MEMAREA_SOURCE_USER_ADDR &&
>>> +        init->source != RTE_MEMAREA_SOURCE_USER_MEMAREA) {
>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s source: %d not supported!\n",
>>> +            init->name, init->source);
>>> +        return -EINVAL;
>>> +    }
>>> +
>>> +    if (init->total_sz <= sizeof(struct memarea_elem)) {
>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s total-size: %zu too small!\n",
>>> +            init->name, init->total_sz);
>>> +        return -EINVAL;
>>> +    }
>>> +
>>> +    if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR && init->user_addr == NULL) {
>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s user provided addr is NULL!\n", init->name);
>>> +        return -EINVAL;
>>> +    }
>>> +
>>> +    if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR &&
>>> +        ((uintptr_t)init->user_addr & (RTE_CACHE_LINE_SIZE - 1))) {
>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s user provided addr should align: %d!\n",
>>> +            init->name, RTE_CACHE_LINE_SIZE);
>>> +        return -EINVAL;
>>> +    }
>>> +
>>> +    if (init->source == RTE_MEMAREA_SOURCE_USER_MEMAREA && init->user_memarea == NULL) {
>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s user provided memarea is NULL!\n", init->name);
>>> +        return -EINVAL;
>>> +    }
>>> +
>>> +    if (init->alg != RTE_MEMAREA_ALG_DEFAULT) {
>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s alg: %d not supported!\n",
>>> +            init->name, init->alg);
>>> +        return -EINVAL;
>>> +    }
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static void *
>>> +memarea_alloc_from_system_api(size_t size)
>>> +{
>>> +    void *ptr = NULL;
>>> +    int ret;
>>> +
>>> +    ret = posix_memalign(&ptr, RTE_CACHE_LINE_SIZE, size);
>>> +    if (ret)
>>> +        return NULL;
>>> +    return ptr;
>>> +}
>>> +
>>> +static void *
>>> +memarea_alloc_area(const struct rte_memarea_param *init)
>>> +{
>>> +    void *ptr = NULL;
>>> +
>>> +    if (init->source == RTE_MEMAREA_SOURCE_RTE_MEMORY)
>>
>> Delete MEMORY. Of course it's memory. What else? If you want to make it clear it's from the RTE heap, it should spell out HEAP. Or MALLOC.
> 
> HEAP seem better.
> 
>>
>>> +        ptr = rte_malloc_socket(NULL, init->total_sz, RTE_CACHE_LINE_SIZE,
>>> +                    init->numa_socket);
>>> +    else if (init->source == RTE_MEMAREA_SOURCE_SYSTEM_API)
>>> +        ptr = memarea_alloc_from_system_api(init->total_sz);
>>
>> "SYSTEM_API" doesn't strike me as a good name.
>>
>> RTE_MEMAREA_SOURCE_LIBC
> 
> LIBC seem better.
> 
>> RTE_MEMAREA_SOURCE_STD_HEAP
>> or at least remove API so it'll be
>> RTE_MEMAREA_SOURCE_SYSTEM
>>
>>> +    else if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR)
>>
>> I would delete "ADDR".
> 
> +1
> 
>>
>>> +        ptr = init->user_addr;
>>> +
>>> +    if (ptr == NULL)
>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s alloc memory area fail!\n", init->name);
>>> +
>>> +    return ptr;
>>> +}
>>> +
>>> +struct rte_memarea *
>>> +rte_memarea_create(const struct rte_memarea_param *init)
>>> +{
>>> +    struct memarea_elem *elem;
>>> +    struct rte_memarea *ma;
>>> +    void *addr;
>>> +    int ret;
>>> +
>>> +    ret = memarea_check_param(init);
>>> +    if (ret)
>>> +        return NULL;
>>> +
>>> +    addr = memarea_alloc_area(init);
>>> +    if (addr == NULL)
>>> +        return NULL;
>>> +
>>> +    ma = rte_zmalloc(NULL, sizeof(struct rte_memarea), RTE_CACHE_LINE_SIZE);
>>> +    if (ma == NULL) {
>>> +        RTE_LOG(ERR, MEMAREA, "malloc memarea: %s management obj fail!\n", init->name);
>>> +        return NULL;
>>> +    }
>>> +
>>> +    ma->init = *init;
>>> +    rte_spinlock_init(&ma->lock);
>>> +    TAILQ_INIT(&ma->elem_list);
>>> +    TAILQ_INIT(&ma->free_list);
>>> +    ma->area_addr = addr;
>>> +    elem = addr;
>>> +    elem->size = init->total_sz - sizeof(struct memarea_elem);
>>> +    elem->cookie = MEMAREA_FREE_ELEM_COOKIE;
>>> +    elem->refcnt = 0;
>>> +    TAILQ_INSERT_TAIL(&ma->elem_list, elem, elem_node);
>>> +    TAILQ_INSERT_TAIL(&ma->free_list, elem, free_node);
>>> +
>>> +    return ma;
>>> +}
>>> +
>>> +static void
>>> +memarea_free_area(struct rte_memarea *ma)
>>> +{
>>> +    if (ma->init.source == RTE_MEMAREA_SOURCE_RTE_MEMORY)
>>> +        rte_free(ma->area_addr);
>>> +    else if (ma->init.source == RTE_MEMAREA_SOURCE_SYSTEM_API)
>>> +        free(ma->area_addr);
>>> +}
>>> +
>>> +void
>>> +rte_memarea_destroy(struct rte_memarea *ma)
>>> +{
>>> +    if (ma == NULL)
>>> +        return;
>>> +    memarea_free_area(ma);
>>> +    rte_free(ma);
>>> +}
>>> diff --git a/lib/memarea/rte_memarea.h b/lib/memarea/rte_memarea.h
>>> new file mode 100644
>>> index 0000000000..543cda4cac
>>> --- /dev/null
>>> +++ b/lib/memarea/rte_memarea.h
>>> @@ -0,0 +1,145 @@
>>> +/* SPDX-License-Identifier: BSD-3-Clause
>>> + * Copyright(c) 2022 HiSilicon Limited
>>> + */
>>> +
>>> +#ifndef RTE_MEMAREA_H
>>> +#define RTE_MEMAREA_H
>>> +
>>> +/**
>>> + * @file
>>> + * RTE Memarea.
>>> + *
>>> + * The memarea is an allocator of variable-size object which based on a memory
>>> + * region. It has the following features:
>>> + *
>>> + * - The default alignment size is RTE_CACHE_LINE_SIZE.
>>
>> This can be read as two things: the object size is aligned, or the start address is aligned.
> 
> It means the start address align, will define more clear in v6.
> 
>>
>>> + * - The memory region can be initialized from the following memory sources:
>>> + *   1. RTE memory: e.g. invoke rte_malloc_socket to obtain.
>>
>> Remove "to obtain", or add "memory" after "obtain". Do you really mean "e.g.", and not "i.e."?
> 
> will fix in v6.
> 
>>
>>> + *   2. System API: e.g. invoke posix_memalign to obtain.
>>> + *   3. User provided address: it can be from extended memory as long as it is
>>> + *      available. The address must be aligned to RTE_CACHE_LINE_SIZE.
>>
>> What is extended memory?
> 
> Like rte_extmen
> 
>>
>>> + *   4) User provided memarea: it can be from another memarea. So we can build
>>> + *      the following memory management structure:
>>> + *         \code{.unparsed}
>>> + *                           -------------
>>> + *                           | memarea-1 |
>>> + *                           -------------
>>> + *                                 |
>>> + *                                 v
>>> + *                  -------------------------------
>>> + *                  |               |             |
>>> + *                  v               v             v
>>> + *            -------------   -------------   ----------
>>> + *            | memarea-2 |   | memarea-3 |   | object |
>>> + *            -------------   -------------   ----------
>>> + *         \endcode
>>> + *      As shown above, the memarea-2/3 both create from memarea-1's memory.
>>> + * - It provides refcnt feature which could be useful in multi-reader scenario.
>>> + * - It supports MT-safe as long as it's specified at creation time. If not
>>> + *   specified, all the functions of the memarea API are lock-free, and assume
>>> + *   to not be invoked in parallel on different logical cores to work on the
>>> + *   same memarea.
>>> + */
>>> +
>>> +#include <stdbool.h>
>>> +#include <stdint.h>
>>> +#include <stdio.h>
>>> +
>>> +#include <rte_compat.h>
>>> +
>>> +#ifdef __cplusplus
>>> +extern "C" {
>>> +#endif
>>> +
>>> +#define RTE_MEMAREA_NAMESIZE    64
>>> +
>>> +/**
>>> + * Memarea memory source.
>>> + */
>>> +enum rte_memarea_source {
>>> +    /** Memory source comes from rte memory. */
>>> +    RTE_MEMAREA_SOURCE_RTE_MEMORY,
>>> +    /** Memory source comes from system API. */
>>> +    RTE_MEMAREA_SOURCE_SYSTEM_API,
>>> +    /** Memory source comes from user-provided address. */
>>> +    RTE_MEMAREA_SOURCE_USER_ADDR,
>>> +    /** Memory source comes from user-provided memarea. */
>>> +    RTE_MEMAREA_SOURCE_USER_MEMAREA,
>>> +};
>>> +
>>> +/**
>>> + * Memarea memory management algorithm.
>>> + */
>>> +enum rte_memarea_alg {
>>> +    /* The default management algorithm is a variant of the next fit
>>> +     * algorithm. It uses a free-list to apply for memory and uses an
>>> +     * element-list in ascending order of address to support merging
>>> +     * upon free.
>>> +     */
>>> +    RTE_MEMAREA_ALG_DEFAULT,
>>> +};

Do you need to expose the algorithm/management scheme option in the 
public API, if there is only one implementation to choose from?

You can always have a rte_memarea_create_alg(/../) in the future, or 
just change the signature between ABI-breaking releases.

Also, shouldn't the default algorithm have name? Rather than just 
DEFAULT. RTE_MEMAREA_ALG_NEXTFIT maybe.

>>> +
>>> +struct rte_memarea;
>>> +
>>> +struct rte_memarea_param {
>>
>> Does this struct need to be public?
> 
> Yes, the rte_memarea_param contains create parameters for create memarea which need be public.
> 

Why isn't the public API just a bunch of create-function parameters? Or, 
alternatively, you have an assortment of create functions, for different 
combinations of parameters. Then you don't have to think about having 
reserved bits or other kind of ABI-related issues due to the struct 
being public.

> And rte_memarea which pointer implementation struction which just a declare here.
> 
>>
>>> +    char name[RTE_MEMAREA_NAMESIZE]; /**< Name of memarea. */
>>> +    enum rte_memarea_source source;  /**< Memory source of memarea. */
>>> +    enum rte_memarea_alg alg;        /**< Memory management algorithm. */
>>> +    size_t total_sz;                 /**< total size (bytes) of memarea. */
>>> +    /** Indicates whether the memarea API should be MT-safe. */
>>> +    uint32_t mt_safe : 1;
>>
>> Why not bool?
> 
> Use bit field other than bool will provides more reserved field.
> 
>>
>>> +    union {
>>> +        /** Numa socket from which to apply for memarea's memory, this
>>> +         * field is valid only when the source is set to be
>>> +         * RTE_MEMAREA_SOURCE_RTE_MEMORY.
>>> +         */
>>> +        int numa_socket;
>>> +        /** User provided address, this field is valid only when the
>>> +         * source is set to be RTE_MEMAREA_SOURCE_USER_ADDR.
>>> +         * Note: the provided address must align at least
>>> +         * RTE_CACHE_LINE_SIZE.
>>> +         */
>>> +        void *user_addr;
>>> +        /** User provided memarea, this field is valid only when the
>>> +         * source is set to be RTE_MEMAREA_SOURCE_USER_MEMAREA.
>>> +         */
>>> +        struct rte_memarea *user_memarea;
>>> +    };
>>> +};
>>> +
>>> +/**
>>> + * @warning
>>> + * @b EXPERIMENTAL: this API may change without prior notice.
>>> + *
>>> + * Create memarea.
>>> + *
>>> + * Create one new memarea.
>>> + *
>>> + * @param init
>>> + *   The init parameter of memarea.
>>> + *
>>> + * @return
>>> + *   Non-NULL on success. Otherwise NULL is returned.
>>> + */
>>> +__rte_experimental
>>> +struct rte_memarea *rte_memarea_create(const struct rte_memarea_param *init);
>>> +
>>> +/**
>>> + * @warning
>>> + * @b EXPERIMENTAL: this API may change without prior notice.
>>> + *
>>> + * Destroy memarea.
>>> + *
>>> + * Destroy the memarea.
>>> + *
>>> + * @param ma
>>> + *   The pointer of memarea.
>>> + */
>>> +__rte_experimental
>>> +void rte_memarea_destroy(struct rte_memarea *ma);
>>> +
>>> +#ifdef __cplusplus
>>> +}
>>> +#endif
>>> +
>>> +#endif /* RTE_MEMAREA_H */
>>> diff --git a/lib/memarea/version.map b/lib/memarea/version.map
>>> new file mode 100644
>>> index 0000000000..f36a04d7cf
>>> --- /dev/null
>>> +++ b/lib/memarea/version.map
>>> @@ -0,0 +1,12 @@
>>> +EXPERIMENTAL {
>>> +    global:
>>> +
>>> +    rte_memarea_create;
>>> +    rte_memarea_destroy;
>>> +
>>> +    local: *;
>>> +};
>>> +
>>> +INTERNAL {
>>> +    local: *;
>>> +};
>>> diff --git a/lib/meson.build b/lib/meson.build
>>> index c648f7d800..521a25d6c0 100644
>>> --- a/lib/meson.build
>>> +++ b/lib/meson.build
>>> @@ -42,6 +42,7 @@ libraries = [
>>>            'kni',
>>>            'latencystats',
>>>            'lpm',
>>> +        'memarea',
>>>            'member',
>>>            'pcapng',
>>>            'power',
>>
>> .
  
Chengwen Feng Oct. 10, 2022, 11:33 p.m. UTC | #4
On 2022/10/11 0:53, Mattias Rönnblom wrote:
> On 2022-10-08 09:53, fengchengwen wrote:
>> Hi Mattias, Thanks for your review, most will fix in v6.
>>
>> On 2022/10/7 4:15, Mattias Rönnblom wrote:
>>> On 2022-10-05 06:09, datshan wrote:
>>>> From: Chengwen Feng <fengchengwen@huawei.com>
>>>>
>>>> The memarea library is an allocator of variable-size object which 
>>>> based
>>>> on a memory region.
>>>>
>>>> This patch provides create/destroy API.
>>>>
>>>> Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
>>>> ---
>>>>    MAINTAINERS                            |   5 +
>>>>    doc/api/doxy-api-index.md              |   3 +-
>>>>    doc/api/doxy-api.conf.in               |   1 +
>>>>    doc/guides/prog_guide/index.rst        |   1 +
>>>>    doc/guides/prog_guide/memarea_lib.rst  |  39 ++++++
>>>>    doc/guides/rel_notes/release_22_11.rst |   6 +
>>>>    lib/eal/common/eal_common_log.c        |   1 +
>>>>    lib/eal/include/rte_log.h              |   1 +
>>>>    lib/memarea/memarea_private.h          |  30 +++++
>>>>    lib/memarea/meson.build                |  16 +++
>>>>    lib/memarea/rte_memarea.c              | 157 
>>>> +++++++++++++++++++++++++
>>>>    lib/memarea/rte_memarea.h              | 145 
>>>> +++++++++++++++++++++++
>>>>    lib/memarea/version.map                |  12 ++
>>>>    lib/meson.build                        |   1 +
>>>>    14 files changed, 417 insertions(+), 1 deletion(-)
>>>>    create mode 100644 doc/guides/prog_guide/memarea_lib.rst
>>>>    create mode 100644 lib/memarea/memarea_private.h
>>>>    create mode 100644 lib/memarea/meson.build
>>>>    create mode 100644 lib/memarea/rte_memarea.c
>>>>    create mode 100644 lib/memarea/rte_memarea.h
>>>>    create mode 100644 lib/memarea/version.map
>>>>
>>>> diff --git a/MAINTAINERS b/MAINTAINERS
>>>> index a55b379d73..b9c638221d 100644
>>>> --- a/MAINTAINERS
>>>> +++ b/MAINTAINERS
>>>> @@ -1550,6 +1550,11 @@ F: app/test/test_lpm*
>>>>    F: app/test/test_func_reentrancy.c
>>>>    F: app/test/test_xmmt_ops.h
>>>>    +Memarea - EXPERIMENTAL
>>>> +M: Chengwen Feng <fengchengwen@huawei.com>
>>>> +F: lib/memarea
>>>> +F: doc/guides/prog_guide/memarea_lib.rst
>>>> +
>>>>    Membership - EXPERIMENTAL
>>>>    M: Yipeng Wang <yipeng1.wang@intel.com>
>>>>    M: Sameh Gobriel <sameh.gobriel@intel.com>
>>>> diff --git a/doc/api/doxy-api-index.md b/doc/api/doxy-api-index.md
>>>> index de488c7abf..24456604f8 100644
>>>> --- a/doc/api/doxy-api-index.md
>>>> +++ b/doc/api/doxy-api-index.md
>>>> @@ -62,7 +62,8 @@ The public API headers are grouped by topics:
>>>>      [memzone](@ref rte_memzone.h),
>>>>      [mempool](@ref rte_mempool.h),
>>>>      [malloc](@ref rte_malloc.h),
>>>> -  [memcpy](@ref rte_memcpy.h)
>>>> +  [memcpy](@ref rte_memcpy.h),
>>>> +  [memarea](@ref rte_memarea.h)
>>>>      - **timers**:
>>>>      [cycles](@ref rte_cycles.h),
>>>> diff --git a/doc/api/doxy-api.conf.in b/doc/api/doxy-api.conf.in
>>>> index f0886c3bd1..8334ebcbd6 100644
>>>> --- a/doc/api/doxy-api.conf.in
>>>> +++ b/doc/api/doxy-api.conf.in
>>>> @@ -53,6 +53,7 @@ INPUT                   = 
>>>> @TOPDIR@/doc/api/doxy-api-index.md \
>>>>                              @TOPDIR@/lib/latencystats \
>>>>                              @TOPDIR@/lib/lpm \
>>>>                              @TOPDIR@/lib/mbuf \
>>>> +                          @TOPDIR@/lib/memarea \
>>>>                              @TOPDIR@/lib/member \
>>>>                              @TOPDIR@/lib/mempool \
>>>>                              @TOPDIR@/lib/meter \
>>>> diff --git a/doc/guides/prog_guide/index.rst 
>>>> b/doc/guides/prog_guide/index.rst
>>>> index 8564883018..e9015d65e3 100644
>>>> --- a/doc/guides/prog_guide/index.rst
>>>> +++ b/doc/guides/prog_guide/index.rst
>>>> @@ -37,6 +37,7 @@ Programmer's Guide
>>>>        hash_lib
>>>>        toeplitz_hash_lib
>>>>        efd_lib
>>>> +    memarea_lib
>>>>        member_lib
>>>>        lpm_lib
>>>>        lpm6_lib
>>>> diff --git a/doc/guides/prog_guide/memarea_lib.rst 
>>>> b/doc/guides/prog_guide/memarea_lib.rst
>>>> new file mode 100644
>>>> index 0000000000..b96dad15f6
>>>> --- /dev/null
>>>> +++ b/doc/guides/prog_guide/memarea_lib.rst
>>>> @@ -0,0 +1,39 @@
>>>> +..  SPDX-License-Identifier: BSD-3-Clause
>>>> +    Copyright(c) 2022 HiSilicon Limited
>>>> +
>>>> +Memarea Library
>>>> +===============
>>>> +
>>>> +Introduction
>>>> +------------
>>>> +
>>>> +The memarea library provides an allocator of variable-size 
>>>> objects, it is
>>>> +oriented towards the application layer, which could provides 
>>>> 'region-based
>>>> +memory management' function [1].
>>>> +
>>>> +The main features are as follows:
>>>> +
>>>> +* The default aligement size is ``RTE_CACHE_LINE_SIZE``.
>>>> +
>>>> +* The memory region can be initialized from the following memory 
>>>> sources:
>>>> +  a) RTE memory: e.g. invoke ``rte_malloc_socket`` to obtain. b) 
>>>> System API:
>>>> +  e.g. invoke posix_memalign to obtain. c) User provided address: 
>>>> it can be from
>>>> +  extendedd memory as long as it is available. d) User provided 
>>>> memarea: it can
>>>> +  be from another memarea.
>>>> +
>>>> +* It provides refcnt feature which could be useful in multi-reader 
>>>> scenario.
>>>> +
>>>> +* It supports MT-safe as long as it's specified at creation time.
>>>> +
>>>> +Library API Overview
>>>> +--------------------
>>>> +
>>>> +The ``rte_memarea_create()`` function is used to create a memarea, 
>>>> the function
>>>> +returns the pointer to the created memarea or ``NULL`` if the 
>>>> creation failed.
>>>> +
>>>> +The ``rte_memarea_destroy()`` function is used to destroy a memarea.
>>>> +
>>>> +Reference
>>>> +---------
>>>> +
>>>> +[1] https://en.wikipedia.org/wiki/Region-based_memory_management
>>>> diff --git a/doc/guides/rel_notes/release_22_11.rst 
>>>> b/doc/guides/rel_notes/release_22_11.rst
>>>> index 5d8ef669b8..4c1f760b98 100644
>>>> --- a/doc/guides/rel_notes/release_22_11.rst
>>>> +++ b/doc/guides/rel_notes/release_22_11.rst
>>>> @@ -55,6 +55,12 @@ New Features
>>>>         Also, make sure to start the actual text at the margin.
>>>> =======================================================
>>>>    +* **Added memarea library.**
>>>> +
>>>> +  The memarea library is an allocator of variable-size objects, it 
>>>> is oriented
>>>> +  towards the application layer, which could provides 
>>>> 'region-based memory
>>>> +  management' function.
>>>> +
>>>>    * **Added configuration for asynchronous flow connection 
>>>> tracking.**
>>>>        Added connection tracking action number hint to 
>>>> ``rte_flow_configure``
>>>> diff --git a/lib/eal/common/eal_common_log.c 
>>>> b/lib/eal/common/eal_common_log.c
>>>> index bd7b188ceb..3d62af59c6 100644
>>>> --- a/lib/eal/common/eal_common_log.c
>>>> +++ b/lib/eal/common/eal_common_log.c
>>>> @@ -369,6 +369,7 @@ static const struct logtype logtype_strings[] = {
>>>>        {RTE_LOGTYPE_EFD,        "lib.efd"},
>>>>        {RTE_LOGTYPE_EVENTDEV,   "lib.eventdev"},
>>>>        {RTE_LOGTYPE_GSO,        "lib.gso"},
>>>> +    {RTE_LOGTYPE_MEMAREA,    "lib.memarea"},
>>>>        {RTE_LOGTYPE_USER1,      "user1"},
>>>>        {RTE_LOGTYPE_USER2,      "user2"},
>>>>        {RTE_LOGTYPE_USER3,      "user3"},
>>>> diff --git a/lib/eal/include/rte_log.h b/lib/eal/include/rte_log.h
>>>> index 25ce42cdfc..708f3a39dd 100644
>>>> --- a/lib/eal/include/rte_log.h
>>>> +++ b/lib/eal/include/rte_log.h
>>>> @@ -48,6 +48,7 @@ extern "C" {
>>>>    #define RTE_LOGTYPE_EFD       18 /**< Log related to EFD. */
>>>>    #define RTE_LOGTYPE_EVENTDEV  19 /**< Log related to eventdev. */
>>>>    #define RTE_LOGTYPE_GSO       20 /**< Log related to GSO. */
>>>> +#define RTE_LOGTYPE_MEMAREA   21 /**< Log related to memarea. */
>>>>      /* these log types can be used in an application */
>>>>    #define RTE_LOGTYPE_USER1     24 /**< User-defined log type 1. */
>>>> diff --git a/lib/memarea/memarea_private.h 
>>>> b/lib/memarea/memarea_private.h
>>>> new file mode 100644
>>>> index 0000000000..c76392d3e6
>>>> --- /dev/null
>>>> +++ b/lib/memarea/memarea_private.h
>>>> @@ -0,0 +1,30 @@
>>>> +/* SPDX-License-Identifier: BSD-3-Clause
>>>> + * Copyright(c) 2022 HiSilicon Limited
>>>> + */
>>>> +
>>>> +#ifndef MEMAREA_PRIVATE_H
>>>> +#define MEMAREA_PRIVATE_H
>>>> +
>>>> +#include <rte_memarea.h>
>>>> +
>>>> +#define MEMAREA_FREE_ELEM_COOKIE    0xFFFFFFFF
>>>> +
>>>> +struct memarea_elem {
>>>> +    size_t   size;
>>>> +    uint32_t cookie;
>>>> +    int32_t  refcnt; /* Non-zero indicates that it has been 
>>>> allocated */
>>>> +    TAILQ_ENTRY(memarea_elem) elem_node;
>>>> +    TAILQ_ENTRY(memarea_elem) free_node;
>>>> +} __rte_cache_aligned;
>>>> +
>>>
>>> Why is the elem type cache line aligned? Need the elem data start be 
>>> cache line aligned?
>>
>> Yes, the elem data align at cache-line default.
>>
>>>
>>>> +TAILQ_HEAD(memarea_elem_list, memarea_elem);
>>>> +
>>>> +struct rte_memarea {
>>>> +    struct rte_memarea_param init;
>>>> +    rte_spinlock_t           lock;
>>>> +    void                    *area_addr;
>>>> +    struct memarea_elem_list elem_list;
>>>> +    struct memarea_elem_list free_list;
>>>> +} __rte_cache_aligned;
>>>> +
>>>> +#endif /* MEMAREA_PRIVATE_H */
>>>> diff --git a/lib/memarea/meson.build b/lib/memarea/meson.build
>>>> new file mode 100644
>>>> index 0000000000..0a74fb4cd1
>>>> --- /dev/null
>>>> +++ b/lib/memarea/meson.build
>>>> @@ -0,0 +1,16 @@
>>>> +# SPDX-License-Identifier: BSD-3-Clause
>>>> +# Copyright(c) 2022 HiSilicon Limited
>>>> +
>>>> +if is_windows
>>>> +    build = false
>>>> +    reason = 'not supported on Windows'
>>>> +    subdir_done()
>>>> +endif
>>>> +
>>>> +sources = files(
>>>> +        'rte_memarea.c',
>>>> +)
>>>> +headers = files(
>>>> +        'rte_memarea.h',
>>>> +)
>>>> +deps += []
>>>> diff --git a/lib/memarea/rte_memarea.c b/lib/memarea/rte_memarea.c
>>>> new file mode 100644
>>>> index 0000000000..868da7661d
>>>> --- /dev/null
>>>> +++ b/lib/memarea/rte_memarea.c
>>>> @@ -0,0 +1,157 @@
>>>> +/* SPDX-License-Identifier: BSD-3-Clause
>>>> + * Copyright(c) 2022 HiSilicon Limited
>>>> + */
>>>> +
>>>> +#include <stdio.h>
>>>> +#include <stdlib.h>
>>>> +
>>>> +#include <rte_common.h>
>>>> +#include <rte_log.h>
>>>> +#include <rte_malloc.h>
>>>> +#include <rte_spinlock.h>
>>>> +
>>>> +#include "rte_memarea.h"
>>>> +#include "memarea_private.h"
>>>> +
>>>> +static int
>>>> +memarea_check_param(const struct rte_memarea_param *init)
>>>> +{
>>>> +    size_t len;
>>>> +
>>>> +    if (init == NULL) {
>>>> +        RTE_LOG(ERR, MEMAREA, "memarea init param is NULL!\n");
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    len = strnlen(init->name, RTE_MEMAREA_NAMESIZE);
>>>> +    if (len == 0 || len >= RTE_MEMAREA_NAMESIZE) {
>>>> +        RTE_LOG(ERR, MEMAREA, "memarea name size %zu invalid!\n", 
>>>> len);
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    if (init->source != RTE_MEMAREA_SOURCE_RTE_MEMORY &&
>>>> +        init->source != RTE_MEMAREA_SOURCE_SYSTEM_API &&
>>>> +        init->source != RTE_MEMAREA_SOURCE_USER_ADDR &&
>>>> +        init->source != RTE_MEMAREA_SOURCE_USER_MEMAREA) {
>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s source: %d not 
>>>> supported!\n",
>>>> +            init->name, init->source);
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    if (init->total_sz <= sizeof(struct memarea_elem)) {
>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s total-size: %zu too 
>>>> small!\n",
>>>> +            init->name, init->total_sz);
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR && 
>>>> init->user_addr == NULL) {
>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s user provided addr is 
>>>> NULL!\n", init->name);
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR &&
>>>> +        ((uintptr_t)init->user_addr & (RTE_CACHE_LINE_SIZE - 1))) {
>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s user provided addr 
>>>> should align: %d!\n",
>>>> +            init->name, RTE_CACHE_LINE_SIZE);
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    if (init->source == RTE_MEMAREA_SOURCE_USER_MEMAREA && 
>>>> init->user_memarea == NULL) {
>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s user provided memarea 
>>>> is NULL!\n", init->name);
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    if (init->alg != RTE_MEMAREA_ALG_DEFAULT) {
>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s alg: %d not supported!\n",
>>>> +            init->name, init->alg);
>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +static void *
>>>> +memarea_alloc_from_system_api(size_t size)
>>>> +{
>>>> +    void *ptr = NULL;
>>>> +    int ret;
>>>> +
>>>> +    ret = posix_memalign(&ptr, RTE_CACHE_LINE_SIZE, size);
>>>> +    if (ret)
>>>> +        return NULL;
>>>> +    return ptr;
>>>> +}
>>>> +
>>>> +static void *
>>>> +memarea_alloc_area(const struct rte_memarea_param *init)
>>>> +{
>>>> +    void *ptr = NULL;
>>>> +
>>>> +    if (init->source == RTE_MEMAREA_SOURCE_RTE_MEMORY)
>>>
>>> Delete MEMORY. Of course it's memory. What else? If you want to make 
>>> it clear it's from the RTE heap, it should spell out HEAP. Or MALLOC.
>>
>> HEAP seem better.
>>
>>>
>>>> +        ptr = rte_malloc_socket(NULL, init->total_sz, 
>>>> RTE_CACHE_LINE_SIZE,
>>>> +                    init->numa_socket);
>>>> +    else if (init->source == RTE_MEMAREA_SOURCE_SYSTEM_API)
>>>> +        ptr = memarea_alloc_from_system_api(init->total_sz);
>>>
>>> "SYSTEM_API" doesn't strike me as a good name.
>>>
>>> RTE_MEMAREA_SOURCE_LIBC
>>
>> LIBC seem better.
>>
>>> RTE_MEMAREA_SOURCE_STD_HEAP
>>> or at least remove API so it'll be
>>> RTE_MEMAREA_SOURCE_SYSTEM
>>>
>>>> +    else if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR)
>>>
>>> I would delete "ADDR".
>>
>> +1
>>
>>>
>>>> +        ptr = init->user_addr;
>>>> +
>>>> +    if (ptr == NULL)
>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s alloc memory area 
>>>> fail!\n", init->name);
>>>> +
>>>> +    return ptr;
>>>> +}
>>>> +
>>>> +struct rte_memarea *
>>>> +rte_memarea_create(const struct rte_memarea_param *init)
>>>> +{
>>>> +    struct memarea_elem *elem;
>>>> +    struct rte_memarea *ma;
>>>> +    void *addr;
>>>> +    int ret;
>>>> +
>>>> +    ret = memarea_check_param(init);
>>>> +    if (ret)
>>>> +        return NULL;
>>>> +
>>>> +    addr = memarea_alloc_area(init);
>>>> +    if (addr == NULL)
>>>> +        return NULL;
>>>> +
>>>> +    ma = rte_zmalloc(NULL, sizeof(struct rte_memarea), 
>>>> RTE_CACHE_LINE_SIZE);
>>>> +    if (ma == NULL) {
>>>> +        RTE_LOG(ERR, MEMAREA, "malloc memarea: %s management obj 
>>>> fail!\n", init->name);
>>>> +        return NULL;
>>>> +    }
>>>> +
>>>> +    ma->init = *init;
>>>> +    rte_spinlock_init(&ma->lock);
>>>> +    TAILQ_INIT(&ma->elem_list);
>>>> +    TAILQ_INIT(&ma->free_list);
>>>> +    ma->area_addr = addr;
>>>> +    elem = addr;
>>>> +    elem->size = init->total_sz - sizeof(struct memarea_elem);
>>>> +    elem->cookie = MEMAREA_FREE_ELEM_COOKIE;
>>>> +    elem->refcnt = 0;
>>>> +    TAILQ_INSERT_TAIL(&ma->elem_list, elem, elem_node);
>>>> +    TAILQ_INSERT_TAIL(&ma->free_list, elem, free_node);
>>>> +
>>>> +    return ma;
>>>> +}
>>>> +
>>>> +static void
>>>> +memarea_free_area(struct rte_memarea *ma)
>>>> +{
>>>> +    if (ma->init.source == RTE_MEMAREA_SOURCE_RTE_MEMORY)
>>>> +        rte_free(ma->area_addr);
>>>> +    else if (ma->init.source == RTE_MEMAREA_SOURCE_SYSTEM_API)
>>>> +        free(ma->area_addr);
>>>> +}
>>>> +
>>>> +void
>>>> +rte_memarea_destroy(struct rte_memarea *ma)
>>>> +{
>>>> +    if (ma == NULL)
>>>> +        return;
>>>> +    memarea_free_area(ma);
>>>> +    rte_free(ma);
>>>> +}
>>>> diff --git a/lib/memarea/rte_memarea.h b/lib/memarea/rte_memarea.h
>>>> new file mode 100644
>>>> index 0000000000..543cda4cac
>>>> --- /dev/null
>>>> +++ b/lib/memarea/rte_memarea.h
>>>> @@ -0,0 +1,145 @@
>>>> +/* SPDX-License-Identifier: BSD-3-Clause
>>>> + * Copyright(c) 2022 HiSilicon Limited
>>>> + */
>>>> +
>>>> +#ifndef RTE_MEMAREA_H
>>>> +#define RTE_MEMAREA_H
>>>> +
>>>> +/**
>>>> + * @file
>>>> + * RTE Memarea.
>>>> + *
>>>> + * The memarea is an allocator of variable-size object which based 
>>>> on a memory
>>>> + * region. It has the following features:
>>>> + *
>>>> + * - The default alignment size is RTE_CACHE_LINE_SIZE.
>>>
>>> This can be read as two things: the object size is aligned, or the 
>>> start address is aligned.
>>
>> It means the start address align, will define more clear in v6.
>>
>>>
>>>> + * - The memory region can be initialized from the following 
>>>> memory sources:
>>>> + *   1. RTE memory: e.g. invoke rte_malloc_socket to obtain.
>>>
>>> Remove "to obtain", or add "memory" after "obtain". Do you really 
>>> mean "e.g.", and not "i.e."?
>>
>> will fix in v6.
>>
>>>
>>>> + *   2. System API: e.g. invoke posix_memalign to obtain.
>>>> + *   3. User provided address: it can be from extended memory as 
>>>> long as it is
>>>> + *      available. The address must be aligned to 
>>>> RTE_CACHE_LINE_SIZE.
>>>
>>> What is extended memory?
>>
>> Like rte_extmen
>>
>>>
>>>> + *   4) User provided memarea: it can be from another memarea. So 
>>>> we can build
>>>> + *      the following memory management structure:
>>>> + *         \code{.unparsed}
>>>> + *                           -------------
>>>> + *                           | memarea-1 |
>>>> + *                           -------------
>>>> + *                                 |
>>>> + *                                 v
>>>> + *                  -------------------------------
>>>> + *                  |               |             |
>>>> + *                  v               v             v
>>>> + *            -------------   -------------   ----------
>>>> + *            | memarea-2 |   | memarea-3 |   | object |
>>>> + *            -------------   -------------   ----------
>>>> + *         \endcode
>>>> + *      As shown above, the memarea-2/3 both create from 
>>>> memarea-1's memory.
>>>> + * - It provides refcnt feature which could be useful in 
>>>> multi-reader scenario.
>>>> + * - It supports MT-safe as long as it's specified at creation 
>>>> time. If not
>>>> + *   specified, all the functions of the memarea API are 
>>>> lock-free, and assume
>>>> + *   to not be invoked in parallel on different logical cores to 
>>>> work on the
>>>> + *   same memarea.
>>>> + */
>>>> +
>>>> +#include <stdbool.h>
>>>> +#include <stdint.h>
>>>> +#include <stdio.h>
>>>> +
>>>> +#include <rte_compat.h>
>>>> +
>>>> +#ifdef __cplusplus
>>>> +extern "C" {
>>>> +#endif
>>>> +
>>>> +#define RTE_MEMAREA_NAMESIZE    64
>>>> +
>>>> +/**
>>>> + * Memarea memory source.
>>>> + */
>>>> +enum rte_memarea_source {
>>>> +    /** Memory source comes from rte memory. */
>>>> +    RTE_MEMAREA_SOURCE_RTE_MEMORY,
>>>> +    /** Memory source comes from system API. */
>>>> +    RTE_MEMAREA_SOURCE_SYSTEM_API,
>>>> +    /** Memory source comes from user-provided address. */
>>>> +    RTE_MEMAREA_SOURCE_USER_ADDR,
>>>> +    /** Memory source comes from user-provided memarea. */
>>>> +    RTE_MEMAREA_SOURCE_USER_MEMAREA,
>>>> +};
>>>> +
>>>> +/**
>>>> + * Memarea memory management algorithm.
>>>> + */
>>>> +enum rte_memarea_alg {
>>>> +    /* The default management algorithm is a variant of the next fit
>>>> +     * algorithm. It uses a free-list to apply for memory and uses an
>>>> +     * element-list in ascending order of address to support merging
>>>> +     * upon free.
>>>> +     */
>>>> +    RTE_MEMAREA_ALG_DEFAULT,
>>>> +};
>
> Do you need to expose the algorithm/management scheme option in the 
> public API, if there is only one implementation to choose from?


Yes, we plan to support SLAB algorithm in future by adding a new alg.


>
> You can always have a rte_memarea_create_alg(/../) in the future, or 
> just change the signature between ABI-breaking releases.


I don't think add a new API is a good idea.

You can see that, we put all init parameter in one struct in this 
design, and could extend function by adding new field .


>
>
> Also, shouldn't the default algorithm have name? Rather than just 
> DEFAULT. RTE_MEMAREA_ALG_NEXTFIT maybe.


Yes, will fix in next version.


>
>>>> +
>>>> +struct rte_memarea;
>>>> +
>>>> +struct rte_memarea_param {
>>>
>>> Does this struct need to be public?
>>
>> Yes, the rte_memarea_param contains create parameters for create 
>> memarea which need be public.
>>
>
> Why isn't the public API just a bunch of create-function parameters? 
> Or, alternatively, you have an assortment of create functions, for 
> different combinations of parameters. Then you don't have to think 
> about having reserved bits or other kind of ABI-related issues due to 
> the struct being public.


These are two API design styles,and I prefer the one create-function API 
style just it seem simple (by inner usage voice).


>
>> And rte_memarea which pointer implementation struction which just a 
>> declare here.
>>
>>>
>>>> +    char name[RTE_MEMAREA_NAMESIZE]; /**< Name of memarea. */
>>>> +    enum rte_memarea_source source;  /**< Memory source of 
>>>> memarea. */
>>>> +    enum rte_memarea_alg alg;        /**< Memory management 
>>>> algorithm. */
>>>> +    size_t total_sz;                 /**< total size (bytes) of 
>>>> memarea. */
>>>> +    /** Indicates whether the memarea API should be MT-safe. */
>>>> +    uint32_t mt_safe : 1;
>>>
>>> Why not bool?
>>
>> Use bit field other than bool will provides more reserved field.
>>
>>>
>>>> +    union {
>>>> +        /** Numa socket from which to apply for memarea's memory, 
>>>> this
>>>> +         * field is valid only when the source is set to be
>>>> +         * RTE_MEMAREA_SOURCE_RTE_MEMORY.
>>>> +         */
>>>> +        int numa_socket;
>>>> +        /** User provided address, this field is valid only when the
>>>> +         * source is set to be RTE_MEMAREA_SOURCE_USER_ADDR.
>>>> +         * Note: the provided address must align at least
>>>> +         * RTE_CACHE_LINE_SIZE.
>>>> +         */
>>>> +        void *user_addr;
>>>> +        /** User provided memarea, this field is valid only when the
>>>> +         * source is set to be RTE_MEMAREA_SOURCE_USER_MEMAREA.
>>>> +         */
>>>> +        struct rte_memarea *user_memarea;
>>>> +    };
>>>> +};
>>>> +
>>>> +/**
>>>> + * @warning
>>>> + * @b EXPERIMENTAL: this API may change without prior notice.
>>>> + *
>>>> + * Create memarea.
>>>> + *
>>>> + * Create one new memarea.
>>>> + *
>>>> + * @param init
>>>> + *   The init parameter of memarea.
>>>> + *
>>>> + * @return
>>>> + *   Non-NULL on success. Otherwise NULL is returned.
>>>> + */
>>>> +__rte_experimental
>>>> +struct rte_memarea *rte_memarea_create(const struct 
>>>> rte_memarea_param *init);
>>>> +
>>>> +/**
>>>> + * @warning
>>>> + * @b EXPERIMENTAL: this API may change without prior notice.
>>>> + *
>>>> + * Destroy memarea.
>>>> + *
>>>> + * Destroy the memarea.
>>>> + *
>>>> + * @param ma
>>>> + *   The pointer of memarea.
>>>> + */
>>>> +__rte_experimental
>>>> +void rte_memarea_destroy(struct rte_memarea *ma);
>>>> +
>>>> +#ifdef __cplusplus
>>>> +}
>>>> +#endif
>>>> +
>>>> +#endif /* RTE_MEMAREA_H */
>>>> diff --git a/lib/memarea/version.map b/lib/memarea/version.map
>>>> new file mode 100644
>>>> index 0000000000..f36a04d7cf
>>>> --- /dev/null
>>>> +++ b/lib/memarea/version.map
>>>> @@ -0,0 +1,12 @@
>>>> +EXPERIMENTAL {
>>>> +    global:
>>>> +
>>>> +    rte_memarea_create;
>>>> +    rte_memarea_destroy;
>>>> +
>>>> +    local: *;
>>>> +};
>>>> +
>>>> +INTERNAL {
>>>> +    local: *;
>>>> +};
>>>> diff --git a/lib/meson.build b/lib/meson.build
>>>> index c648f7d800..521a25d6c0 100644
>>>> --- a/lib/meson.build
>>>> +++ b/lib/meson.build
>>>> @@ -42,6 +42,7 @@ libraries = [
>>>>            'kni',
>>>>            'latencystats',
>>>>            'lpm',
>>>> +        'memarea',
>>>>            'member',
>>>>            'pcapng',
>>>>            'power',
>>>
>>> .
>
  
Mattias Rönnblom Oct. 11, 2022, 3:35 p.m. UTC | #5
On 2022-10-11 01:33, fengchengwen wrote:
> On 2022/10/11 0:53, Mattias Rönnblom wrote:
>> On 2022-10-08 09:53, fengchengwen wrote:
>>> Hi Mattias, Thanks for your review, most will fix in v6.
>>>
>>> On 2022/10/7 4:15, Mattias Rönnblom wrote:
>>>> On 2022-10-05 06:09, datshan wrote:
>>>>> From: Chengwen Feng <fengchengwen@huawei.com>
>>>>>
>>>>> The memarea library is an allocator of variable-size object which 
>>>>> based
>>>>> on a memory region.
>>>>>
>>>>> This patch provides create/destroy API.
>>>>>
>>>>> Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
>>>>> ---
>>>>>    MAINTAINERS                            |   5 +
>>>>>    doc/api/doxy-api-index.md              |   3 +-
>>>>>    doc/api/doxy-api.conf.in               |   1 +
>>>>>    doc/guides/prog_guide/index.rst        |   1 +
>>>>>    doc/guides/prog_guide/memarea_lib.rst  |  39 ++++++
>>>>>    doc/guides/rel_notes/release_22_11.rst |   6 +
>>>>>    lib/eal/common/eal_common_log.c        |   1 +
>>>>>    lib/eal/include/rte_log.h              |   1 +
>>>>>    lib/memarea/memarea_private.h          |  30 +++++
>>>>>    lib/memarea/meson.build                |  16 +++
>>>>>    lib/memarea/rte_memarea.c              | 157 
>>>>> +++++++++++++++++++++++++
>>>>>    lib/memarea/rte_memarea.h              | 145 
>>>>> +++++++++++++++++++++++
>>>>>    lib/memarea/version.map                |  12 ++
>>>>>    lib/meson.build                        |   1 +
>>>>>    14 files changed, 417 insertions(+), 1 deletion(-)
>>>>>    create mode 100644 doc/guides/prog_guide/memarea_lib.rst
>>>>>    create mode 100644 lib/memarea/memarea_private.h
>>>>>    create mode 100644 lib/memarea/meson.build
>>>>>    create mode 100644 lib/memarea/rte_memarea.c
>>>>>    create mode 100644 lib/memarea/rte_memarea.h
>>>>>    create mode 100644 lib/memarea/version.map
>>>>>
>>>>> diff --git a/MAINTAINERS b/MAINTAINERS
>>>>> index a55b379d73..b9c638221d 100644
>>>>> --- a/MAINTAINERS
>>>>> +++ b/MAINTAINERS
>>>>> @@ -1550,6 +1550,11 @@ F: app/test/test_lpm*
>>>>>    F: app/test/test_func_reentrancy.c
>>>>>    F: app/test/test_xmmt_ops.h
>>>>>    +Memarea - EXPERIMENTAL
>>>>> +M: Chengwen Feng <fengchengwen@huawei.com>
>>>>> +F: lib/memarea
>>>>> +F: doc/guides/prog_guide/memarea_lib.rst
>>>>> +
>>>>>    Membership - EXPERIMENTAL
>>>>>    M: Yipeng Wang <yipeng1.wang@intel.com>
>>>>>    M: Sameh Gobriel <sameh.gobriel@intel.com>
>>>>> diff --git a/doc/api/doxy-api-index.md b/doc/api/doxy-api-index.md
>>>>> index de488c7abf..24456604f8 100644
>>>>> --- a/doc/api/doxy-api-index.md
>>>>> +++ b/doc/api/doxy-api-index.md
>>>>> @@ -62,7 +62,8 @@ The public API headers are grouped by topics:
>>>>>      [memzone](@ref rte_memzone.h),
>>>>>      [mempool](@ref rte_mempool.h),
>>>>>      [malloc](@ref rte_malloc.h),
>>>>> -  [memcpy](@ref rte_memcpy.h)
>>>>> +  [memcpy](@ref rte_memcpy.h),
>>>>> +  [memarea](@ref rte_memarea.h)
>>>>>      - **timers**:
>>>>>      [cycles](@ref rte_cycles.h),
>>>>> diff --git a/doc/api/doxy-api.conf.in b/doc/api/doxy-api.conf.in
>>>>> index f0886c3bd1..8334ebcbd6 100644
>>>>> --- a/doc/api/doxy-api.conf.in
>>>>> +++ b/doc/api/doxy-api.conf.in
>>>>> @@ -53,6 +53,7 @@ INPUT                   = 
>>>>> @TOPDIR@/doc/api/doxy-api-index.md \
>>>>>                              @TOPDIR@/lib/latencystats \
>>>>>                              @TOPDIR@/lib/lpm \
>>>>>                              @TOPDIR@/lib/mbuf \
>>>>> +                          @TOPDIR@/lib/memarea \
>>>>>                              @TOPDIR@/lib/member \
>>>>>                              @TOPDIR@/lib/mempool \
>>>>>                              @TOPDIR@/lib/meter \
>>>>> diff --git a/doc/guides/prog_guide/index.rst 
>>>>> b/doc/guides/prog_guide/index.rst
>>>>> index 8564883018..e9015d65e3 100644
>>>>> --- a/doc/guides/prog_guide/index.rst
>>>>> +++ b/doc/guides/prog_guide/index.rst
>>>>> @@ -37,6 +37,7 @@ Programmer's Guide
>>>>>        hash_lib
>>>>>        toeplitz_hash_lib
>>>>>        efd_lib
>>>>> +    memarea_lib
>>>>>        member_lib
>>>>>        lpm_lib
>>>>>        lpm6_lib
>>>>> diff --git a/doc/guides/prog_guide/memarea_lib.rst 
>>>>> b/doc/guides/prog_guide/memarea_lib.rst
>>>>> new file mode 100644
>>>>> index 0000000000..b96dad15f6
>>>>> --- /dev/null
>>>>> +++ b/doc/guides/prog_guide/memarea_lib.rst
>>>>> @@ -0,0 +1,39 @@
>>>>> +..  SPDX-License-Identifier: BSD-3-Clause
>>>>> +    Copyright(c) 2022 HiSilicon Limited
>>>>> +
>>>>> +Memarea Library
>>>>> +===============
>>>>> +
>>>>> +Introduction
>>>>> +------------
>>>>> +
>>>>> +The memarea library provides an allocator of variable-size 
>>>>> objects, it is
>>>>> +oriented towards the application layer, which could provides 
>>>>> 'region-based
>>>>> +memory management' function [1].
>>>>> +
>>>>> +The main features are as follows:
>>>>> +
>>>>> +* The default aligement size is ``RTE_CACHE_LINE_SIZE``.
>>>>> +
>>>>> +* The memory region can be initialized from the following memory 
>>>>> sources:
>>>>> +  a) RTE memory: e.g. invoke ``rte_malloc_socket`` to obtain. b) 
>>>>> System API:
>>>>> +  e.g. invoke posix_memalign to obtain. c) User provided address: 
>>>>> it can be from
>>>>> +  extendedd memory as long as it is available. d) User provided 
>>>>> memarea: it can
>>>>> +  be from another memarea.
>>>>> +
>>>>> +* It provides refcnt feature which could be useful in multi-reader 
>>>>> scenario.
>>>>> +
>>>>> +* It supports MT-safe as long as it's specified at creation time.
>>>>> +
>>>>> +Library API Overview
>>>>> +--------------------
>>>>> +
>>>>> +The ``rte_memarea_create()`` function is used to create a memarea, 
>>>>> the function
>>>>> +returns the pointer to the created memarea or ``NULL`` if the 
>>>>> creation failed.
>>>>> +
>>>>> +The ``rte_memarea_destroy()`` function is used to destroy a memarea.
>>>>> +
>>>>> +Reference
>>>>> +---------
>>>>> +
>>>>> +[1] https://en.wikipedia.org/wiki/Region-based_memory_management
>>>>> diff --git a/doc/guides/rel_notes/release_22_11.rst 
>>>>> b/doc/guides/rel_notes/release_22_11.rst
>>>>> index 5d8ef669b8..4c1f760b98 100644
>>>>> --- a/doc/guides/rel_notes/release_22_11.rst
>>>>> +++ b/doc/guides/rel_notes/release_22_11.rst
>>>>> @@ -55,6 +55,12 @@ New Features
>>>>>         Also, make sure to start the actual text at the margin.
>>>>> =======================================================
>>>>>    +* **Added memarea library.**
>>>>> +
>>>>> +  The memarea library is an allocator of variable-size objects, it 
>>>>> is oriented
>>>>> +  towards the application layer, which could provides 
>>>>> 'region-based memory
>>>>> +  management' function.
>>>>> +
>>>>>    * **Added configuration for asynchronous flow connection 
>>>>> tracking.**
>>>>>        Added connection tracking action number hint to 
>>>>> ``rte_flow_configure``
>>>>> diff --git a/lib/eal/common/eal_common_log.c 
>>>>> b/lib/eal/common/eal_common_log.c
>>>>> index bd7b188ceb..3d62af59c6 100644
>>>>> --- a/lib/eal/common/eal_common_log.c
>>>>> +++ b/lib/eal/common/eal_common_log.c
>>>>> @@ -369,6 +369,7 @@ static const struct logtype logtype_strings[] = {
>>>>>        {RTE_LOGTYPE_EFD,        "lib.efd"},
>>>>>        {RTE_LOGTYPE_EVENTDEV,   "lib.eventdev"},
>>>>>        {RTE_LOGTYPE_GSO,        "lib.gso"},
>>>>> +    {RTE_LOGTYPE_MEMAREA,    "lib.memarea"},
>>>>>        {RTE_LOGTYPE_USER1,      "user1"},
>>>>>        {RTE_LOGTYPE_USER2,      "user2"},
>>>>>        {RTE_LOGTYPE_USER3,      "user3"},
>>>>> diff --git a/lib/eal/include/rte_log.h b/lib/eal/include/rte_log.h
>>>>> index 25ce42cdfc..708f3a39dd 100644
>>>>> --- a/lib/eal/include/rte_log.h
>>>>> +++ b/lib/eal/include/rte_log.h
>>>>> @@ -48,6 +48,7 @@ extern "C" {
>>>>>    #define RTE_LOGTYPE_EFD       18 /**< Log related to EFD. */
>>>>>    #define RTE_LOGTYPE_EVENTDEV  19 /**< Log related to eventdev. */
>>>>>    #define RTE_LOGTYPE_GSO       20 /**< Log related to GSO. */
>>>>> +#define RTE_LOGTYPE_MEMAREA   21 /**< Log related to memarea. */
>>>>>      /* these log types can be used in an application */
>>>>>    #define RTE_LOGTYPE_USER1     24 /**< User-defined log type 1. */
>>>>> diff --git a/lib/memarea/memarea_private.h 
>>>>> b/lib/memarea/memarea_private.h
>>>>> new file mode 100644
>>>>> index 0000000000..c76392d3e6
>>>>> --- /dev/null
>>>>> +++ b/lib/memarea/memarea_private.h
>>>>> @@ -0,0 +1,30 @@
>>>>> +/* SPDX-License-Identifier: BSD-3-Clause
>>>>> + * Copyright(c) 2022 HiSilicon Limited
>>>>> + */
>>>>> +
>>>>> +#ifndef MEMAREA_PRIVATE_H
>>>>> +#define MEMAREA_PRIVATE_H
>>>>> +
>>>>> +#include <rte_memarea.h>
>>>>> +
>>>>> +#define MEMAREA_FREE_ELEM_COOKIE    0xFFFFFFFF
>>>>> +
>>>>> +struct memarea_elem {
>>>>> +    size_t   size;
>>>>> +    uint32_t cookie;
>>>>> +    int32_t  refcnt; /* Non-zero indicates that it has been 
>>>>> allocated */
>>>>> +    TAILQ_ENTRY(memarea_elem) elem_node;
>>>>> +    TAILQ_ENTRY(memarea_elem) free_node;
>>>>> +} __rte_cache_aligned;
>>>>> +
>>>>
>>>> Why is the elem type cache line aligned? Need the elem data start be 
>>>> cache line aligned?
>>>
>>> Yes, the elem data align at cache-line default.
>>>
>>>>
>>>>> +TAILQ_HEAD(memarea_elem_list, memarea_elem);
>>>>> +
>>>>> +struct rte_memarea {
>>>>> +    struct rte_memarea_param init;
>>>>> +    rte_spinlock_t           lock;
>>>>> +    void                    *area_addr;
>>>>> +    struct memarea_elem_list elem_list;
>>>>> +    struct memarea_elem_list free_list;
>>>>> +} __rte_cache_aligned;
>>>>> +
>>>>> +#endif /* MEMAREA_PRIVATE_H */
>>>>> diff --git a/lib/memarea/meson.build b/lib/memarea/meson.build
>>>>> new file mode 100644
>>>>> index 0000000000..0a74fb4cd1
>>>>> --- /dev/null
>>>>> +++ b/lib/memarea/meson.build
>>>>> @@ -0,0 +1,16 @@
>>>>> +# SPDX-License-Identifier: BSD-3-Clause
>>>>> +# Copyright(c) 2022 HiSilicon Limited
>>>>> +
>>>>> +if is_windows
>>>>> +    build = false
>>>>> +    reason = 'not supported on Windows'
>>>>> +    subdir_done()
>>>>> +endif
>>>>> +
>>>>> +sources = files(
>>>>> +        'rte_memarea.c',
>>>>> +)
>>>>> +headers = files(
>>>>> +        'rte_memarea.h',
>>>>> +)
>>>>> +deps += []
>>>>> diff --git a/lib/memarea/rte_memarea.c b/lib/memarea/rte_memarea.c
>>>>> new file mode 100644
>>>>> index 0000000000..868da7661d
>>>>> --- /dev/null
>>>>> +++ b/lib/memarea/rte_memarea.c
>>>>> @@ -0,0 +1,157 @@
>>>>> +/* SPDX-License-Identifier: BSD-3-Clause
>>>>> + * Copyright(c) 2022 HiSilicon Limited
>>>>> + */
>>>>> +
>>>>> +#include <stdio.h>
>>>>> +#include <stdlib.h>
>>>>> +
>>>>> +#include <rte_common.h>
>>>>> +#include <rte_log.h>
>>>>> +#include <rte_malloc.h>
>>>>> +#include <rte_spinlock.h>
>>>>> +
>>>>> +#include "rte_memarea.h"
>>>>> +#include "memarea_private.h"
>>>>> +
>>>>> +static int
>>>>> +memarea_check_param(const struct rte_memarea_param *init)
>>>>> +{
>>>>> +    size_t len;
>>>>> +
>>>>> +    if (init == NULL) {
>>>>> +        RTE_LOG(ERR, MEMAREA, "memarea init param is NULL!\n");
>>>>> +        return -EINVAL;
>>>>> +    }
>>>>> +
>>>>> +    len = strnlen(init->name, RTE_MEMAREA_NAMESIZE);
>>>>> +    if (len == 0 || len >= RTE_MEMAREA_NAMESIZE) {
>>>>> +        RTE_LOG(ERR, MEMAREA, "memarea name size %zu invalid!\n", 
>>>>> len);
>>>>> +        return -EINVAL;
>>>>> +    }
>>>>> +
>>>>> +    if (init->source != RTE_MEMAREA_SOURCE_RTE_MEMORY &&
>>>>> +        init->source != RTE_MEMAREA_SOURCE_SYSTEM_API &&
>>>>> +        init->source != RTE_MEMAREA_SOURCE_USER_ADDR &&
>>>>> +        init->source != RTE_MEMAREA_SOURCE_USER_MEMAREA) {
>>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s source: %d not 
>>>>> supported!\n",
>>>>> +            init->name, init->source);
>>>>> +        return -EINVAL;
>>>>> +    }
>>>>> +
>>>>> +    if (init->total_sz <= sizeof(struct memarea_elem)) {
>>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s total-size: %zu too 
>>>>> small!\n",
>>>>> +            init->name, init->total_sz);
>>>>> +        return -EINVAL;
>>>>> +    }
>>>>> +
>>>>> +    if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR && 
>>>>> init->user_addr == NULL) {
>>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s user provided addr is 
>>>>> NULL!\n", init->name);
>>>>> +        return -EINVAL;
>>>>> +    }
>>>>> +
>>>>> +    if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR &&
>>>>> +        ((uintptr_t)init->user_addr & (RTE_CACHE_LINE_SIZE - 1))) {
>>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s user provided addr 
>>>>> should align: %d!\n",
>>>>> +            init->name, RTE_CACHE_LINE_SIZE);
>>>>> +        return -EINVAL;
>>>>> +    }
>>>>> +
>>>>> +    if (init->source == RTE_MEMAREA_SOURCE_USER_MEMAREA && 
>>>>> init->user_memarea == NULL) {
>>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s user provided memarea 
>>>>> is NULL!\n", init->name);
>>>>> +        return -EINVAL;
>>>>> +    }
>>>>> +
>>>>> +    if (init->alg != RTE_MEMAREA_ALG_DEFAULT) {
>>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s alg: %d not supported!\n",
>>>>> +            init->name, init->alg);
>>>>> +        return -EINVAL;
>>>>> +    }
>>>>> +
>>>>> +    return 0;
>>>>> +}
>>>>> +
>>>>> +static void *
>>>>> +memarea_alloc_from_system_api(size_t size)
>>>>> +{
>>>>> +    void *ptr = NULL;
>>>>> +    int ret;
>>>>> +
>>>>> +    ret = posix_memalign(&ptr, RTE_CACHE_LINE_SIZE, size);
>>>>> +    if (ret)
>>>>> +        return NULL;
>>>>> +    return ptr;
>>>>> +}
>>>>> +
>>>>> +static void *
>>>>> +memarea_alloc_area(const struct rte_memarea_param *init)
>>>>> +{
>>>>> +    void *ptr = NULL;
>>>>> +
>>>>> +    if (init->source == RTE_MEMAREA_SOURCE_RTE_MEMORY)
>>>>
>>>> Delete MEMORY. Of course it's memory. What else? If you want to make 
>>>> it clear it's from the RTE heap, it should spell out HEAP. Or MALLOC.
>>>
>>> HEAP seem better.
>>>
>>>>
>>>>> +        ptr = rte_malloc_socket(NULL, init->total_sz, 
>>>>> RTE_CACHE_LINE_SIZE,
>>>>> +                    init->numa_socket);
>>>>> +    else if (init->source == RTE_MEMAREA_SOURCE_SYSTEM_API)
>>>>> +        ptr = memarea_alloc_from_system_api(init->total_sz);
>>>>
>>>> "SYSTEM_API" doesn't strike me as a good name.
>>>>
>>>> RTE_MEMAREA_SOURCE_LIBC
>>>
>>> LIBC seem better.
>>>
>>>> RTE_MEMAREA_SOURCE_STD_HEAP
>>>> or at least remove API so it'll be
>>>> RTE_MEMAREA_SOURCE_SYSTEM
>>>>
>>>>> +    else if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR)
>>>>
>>>> I would delete "ADDR".
>>>
>>> +1
>>>
>>>>
>>>>> +        ptr = init->user_addr;
>>>>> +
>>>>> +    if (ptr == NULL)
>>>>> +        RTE_LOG(ERR, MEMAREA, "memarea: %s alloc memory area 
>>>>> fail!\n", init->name);
>>>>> +
>>>>> +    return ptr;
>>>>> +}
>>>>> +
>>>>> +struct rte_memarea *
>>>>> +rte_memarea_create(const struct rte_memarea_param *init)
>>>>> +{
>>>>> +    struct memarea_elem *elem;
>>>>> +    struct rte_memarea *ma;
>>>>> +    void *addr;
>>>>> +    int ret;
>>>>> +
>>>>> +    ret = memarea_check_param(init);
>>>>> +    if (ret)
>>>>> +        return NULL;
>>>>> +
>>>>> +    addr = memarea_alloc_area(init);
>>>>> +    if (addr == NULL)
>>>>> +        return NULL;
>>>>> +
>>>>> +    ma = rte_zmalloc(NULL, sizeof(struct rte_memarea), 
>>>>> RTE_CACHE_LINE_SIZE);
>>>>> +    if (ma == NULL) {
>>>>> +        RTE_LOG(ERR, MEMAREA, "malloc memarea: %s management obj 
>>>>> fail!\n", init->name);
>>>>> +        return NULL;
>>>>> +    }
>>>>> +
>>>>> +    ma->init = *init;
>>>>> +    rte_spinlock_init(&ma->lock);
>>>>> +    TAILQ_INIT(&ma->elem_list);
>>>>> +    TAILQ_INIT(&ma->free_list);
>>>>> +    ma->area_addr = addr;
>>>>> +    elem = addr;
>>>>> +    elem->size = init->total_sz - sizeof(struct memarea_elem);
>>>>> +    elem->cookie = MEMAREA_FREE_ELEM_COOKIE;
>>>>> +    elem->refcnt = 0;
>>>>> +    TAILQ_INSERT_TAIL(&ma->elem_list, elem, elem_node);
>>>>> +    TAILQ_INSERT_TAIL(&ma->free_list, elem, free_node);
>>>>> +
>>>>> +    return ma;
>>>>> +}
>>>>> +
>>>>> +static void
>>>>> +memarea_free_area(struct rte_memarea *ma)
>>>>> +{
>>>>> +    if (ma->init.source == RTE_MEMAREA_SOURCE_RTE_MEMORY)
>>>>> +        rte_free(ma->area_addr);
>>>>> +    else if (ma->init.source == RTE_MEMAREA_SOURCE_SYSTEM_API)
>>>>> +        free(ma->area_addr);
>>>>> +}
>>>>> +
>>>>> +void
>>>>> +rte_memarea_destroy(struct rte_memarea *ma)
>>>>> +{
>>>>> +    if (ma == NULL)
>>>>> +        return;
>>>>> +    memarea_free_area(ma);
>>>>> +    rte_free(ma);
>>>>> +}
>>>>> diff --git a/lib/memarea/rte_memarea.h b/lib/memarea/rte_memarea.h
>>>>> new file mode 100644
>>>>> index 0000000000..543cda4cac
>>>>> --- /dev/null
>>>>> +++ b/lib/memarea/rte_memarea.h
>>>>> @@ -0,0 +1,145 @@
>>>>> +/* SPDX-License-Identifier: BSD-3-Clause
>>>>> + * Copyright(c) 2022 HiSilicon Limited
>>>>> + */
>>>>> +
>>>>> +#ifndef RTE_MEMAREA_H
>>>>> +#define RTE_MEMAREA_H
>>>>> +
>>>>> +/**
>>>>> + * @file
>>>>> + * RTE Memarea.
>>>>> + *
>>>>> + * The memarea is an allocator of variable-size object which based 
>>>>> on a memory
>>>>> + * region. It has the following features:
>>>>> + *
>>>>> + * - The default alignment size is RTE_CACHE_LINE_SIZE.
>>>>
>>>> This can be read as two things: the object size is aligned, or the 
>>>> start address is aligned.
>>>
>>> It means the start address align, will define more clear in v6.
>>>
>>>>
>>>>> + * - The memory region can be initialized from the following 
>>>>> memory sources:
>>>>> + *   1. RTE memory: e.g. invoke rte_malloc_socket to obtain.
>>>>
>>>> Remove "to obtain", or add "memory" after "obtain". Do you really 
>>>> mean "e.g.", and not "i.e."?
>>>
>>> will fix in v6.
>>>
>>>>
>>>>> + *   2. System API: e.g. invoke posix_memalign to obtain.
>>>>> + *   3. User provided address: it can be from extended memory as 
>>>>> long as it is
>>>>> + *      available. The address must be aligned to 
>>>>> RTE_CACHE_LINE_SIZE.
>>>>
>>>> What is extended memory?
>>>
>>> Like rte_extmen
>>>
>>>>
>>>>> + *   4) User provided memarea: it can be from another memarea. So 
>>>>> we can build
>>>>> + *      the following memory management structure:
>>>>> + *         \code{.unparsed}
>>>>> + *                           -------------
>>>>> + *                           | memarea-1 |
>>>>> + *                           -------------
>>>>> + *                                 |
>>>>> + *                                 v
>>>>> + *                  -------------------------------
>>>>> + *                  |               |             |
>>>>> + *                  v               v             v
>>>>> + *            -------------   -------------   ----------
>>>>> + *            | memarea-2 |   | memarea-3 |   | object |
>>>>> + *            -------------   -------------   ----------
>>>>> + *         \endcode
>>>>> + *      As shown above, the memarea-2/3 both create from 
>>>>> memarea-1's memory.
>>>>> + * - It provides refcnt feature which could be useful in 
>>>>> multi-reader scenario.
>>>>> + * - It supports MT-safe as long as it's specified at creation 
>>>>> time. If not
>>>>> + *   specified, all the functions of the memarea API are 
>>>>> lock-free, and assume
>>>>> + *   to not be invoked in parallel on different logical cores to 
>>>>> work on the
>>>>> + *   same memarea.
>>>>> + */
>>>>> +
>>>>> +#include <stdbool.h>
>>>>> +#include <stdint.h>
>>>>> +#include <stdio.h>
>>>>> +
>>>>> +#include <rte_compat.h>
>>>>> +
>>>>> +#ifdef __cplusplus
>>>>> +extern "C" {
>>>>> +#endif
>>>>> +
>>>>> +#define RTE_MEMAREA_NAMESIZE    64
>>>>> +
>>>>> +/**
>>>>> + * Memarea memory source.
>>>>> + */
>>>>> +enum rte_memarea_source {
>>>>> +    /** Memory source comes from rte memory. */
>>>>> +    RTE_MEMAREA_SOURCE_RTE_MEMORY,
>>>>> +    /** Memory source comes from system API. */
>>>>> +    RTE_MEMAREA_SOURCE_SYSTEM_API,
>>>>> +    /** Memory source comes from user-provided address. */
>>>>> +    RTE_MEMAREA_SOURCE_USER_ADDR,
>>>>> +    /** Memory source comes from user-provided memarea. */
>>>>> +    RTE_MEMAREA_SOURCE_USER_MEMAREA,
>>>>> +};
>>>>> +
>>>>> +/**
>>>>> + * Memarea memory management algorithm.
>>>>> + */
>>>>> +enum rte_memarea_alg {
>>>>> +    /* The default management algorithm is a variant of the next fit
>>>>> +     * algorithm. It uses a free-list to apply for memory and uses an
>>>>> +     * element-list in ascending order of address to support merging
>>>>> +     * upon free.
>>>>> +     */
>>>>> +    RTE_MEMAREA_ALG_DEFAULT,
>>>>> +};
>>
>> Do you need to expose the algorithm/management scheme option in the 
>> public API, if there is only one implementation to choose from?
> 
> 
> Yes, we plan to support SLAB algorithm in future by adding a new alg.
> 
> 
>>
>> You can always have a rte_memarea_create_alg(/../) in the future, or 
>> just change the signature between ABI-breaking releases.
> 
> 
> I don't think add a new API is a good idea.
> 
> You can see that, we put all init parameter in one struct in this 
> design, and could extend function by adding new field .
> 
> 
>>
>>
>> Also, shouldn't the default algorithm have name? Rather than just 
>> DEFAULT. RTE_MEMAREA_ALG_NEXTFIT maybe.
> 
> 
> Yes, will fix in next version.
> 
> 
>>
>>>>> +
>>>>> +struct rte_memarea;
>>>>> +
>>>>> +struct rte_memarea_param {
>>>>
>>>> Does this struct need to be public?
>>>
>>> Yes, the rte_memarea_param contains create parameters for create 
>>> memarea which need be public.
>>>
>>
>> Why isn't the public API just a bunch of create-function parameters? 
>> Or, alternatively, you have an assortment of create functions, for 
>> different combinations of parameters. Then you don't have to think 
>> about having reserved bits or other kind of ABI-related issues due to 
>> the struct being public.
> 
> 
> These are two API design styles,and I prefer the one create-function 
> API style just it seem simple (by inner usage voice).
> 
> 

My reaction when I saw the test code, was that it was needlessly 
complicated to create a memarea. Intuitions vary, I suppose.

Anyway, the style you prefer is represented elsewhere in DPDK already, 
so I'm good with this.

>>
>>> And rte_memarea which pointer implementation struction which just a 
>>> declare here.
>>>
>>>>
>>>>> +    char name[RTE_MEMAREA_NAMESIZE]; /**< Name of memarea. */
>>>>> +    enum rte_memarea_source source;  /**< Memory source of 
>>>>> memarea. */
>>>>> +    enum rte_memarea_alg alg;        /**< Memory management 
>>>>> algorithm. */
>>>>> +    size_t total_sz;                 /**< total size (bytes) of 
>>>>> memarea. */
>>>>> +    /** Indicates whether the memarea API should be MT-safe. */
>>>>> +    uint32_t mt_safe : 1;
>>>>
>>>> Why not bool?
>>>
>>> Use bit field other than bool will provides more reserved field.
>>>
>>>>
>>>>> +    union {
>>>>> +        /** Numa socket from which to apply for memarea's memory, 
>>>>> this
>>>>> +         * field is valid only when the source is set to be
>>>>> +         * RTE_MEMAREA_SOURCE_RTE_MEMORY.
>>>>> +         */
>>>>> +        int numa_socket;
>>>>> +        /** User provided address, this field is valid only when the
>>>>> +         * source is set to be RTE_MEMAREA_SOURCE_USER_ADDR.
>>>>> +         * Note: the provided address must align at least
>>>>> +         * RTE_CACHE_LINE_SIZE.
>>>>> +         */
>>>>> +        void *user_addr;
>>>>> +        /** User provided memarea, this field is valid only when the
>>>>> +         * source is set to be RTE_MEMAREA_SOURCE_USER_MEMAREA.
>>>>> +         */
>>>>> +        struct rte_memarea *user_memarea;
>>>>> +    };
>>>>> +};
>>>>> +
>>>>> +/**
>>>>> + * @warning
>>>>> + * @b EXPERIMENTAL: this API may change without prior notice.
>>>>> + *
>>>>> + * Create memarea.
>>>>> + *
>>>>> + * Create one new memarea.
>>>>> + *
>>>>> + * @param init
>>>>> + *   The init parameter of memarea.
>>>>> + *
>>>>> + * @return
>>>>> + *   Non-NULL on success. Otherwise NULL is returned.
>>>>> + */
>>>>> +__rte_experimental
>>>>> +struct rte_memarea *rte_memarea_create(const struct 
>>>>> rte_memarea_param *init);
>>>>> +
>>>>> +/**
>>>>> + * @warning
>>>>> + * @b EXPERIMENTAL: this API may change without prior notice.
>>>>> + *
>>>>> + * Destroy memarea.
>>>>> + *
>>>>> + * Destroy the memarea.
>>>>> + *
>>>>> + * @param ma
>>>>> + *   The pointer of memarea.
>>>>> + */
>>>>> +__rte_experimental
>>>>> +void rte_memarea_destroy(struct rte_memarea *ma);
>>>>> +
>>>>> +#ifdef __cplusplus
>>>>> +}
>>>>> +#endif
>>>>> +
>>>>> +#endif /* RTE_MEMAREA_H */
>>>>> diff --git a/lib/memarea/version.map b/lib/memarea/version.map
>>>>> new file mode 100644
>>>>> index 0000000000..f36a04d7cf
>>>>> --- /dev/null
>>>>> +++ b/lib/memarea/version.map
>>>>> @@ -0,0 +1,12 @@
>>>>> +EXPERIMENTAL {
>>>>> +    global:
>>>>> +
>>>>> +    rte_memarea_create;
>>>>> +    rte_memarea_destroy;
>>>>> +
>>>>> +    local: *;
>>>>> +};
>>>>> +
>>>>> +INTERNAL {
>>>>> +    local: *;
>>>>> +};
>>>>> diff --git a/lib/meson.build b/lib/meson.build
>>>>> index c648f7d800..521a25d6c0 100644
>>>>> --- a/lib/meson.build
>>>>> +++ b/lib/meson.build
>>>>> @@ -42,6 +42,7 @@ libraries = [
>>>>>            'kni',
>>>>>            'latencystats',
>>>>>            'lpm',
>>>>> +        'memarea',
>>>>>            'member',
>>>>>            'pcapng',
>>>>>            'power',
>>>>
>>>> .
>>
  

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index a55b379d73..b9c638221d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1550,6 +1550,11 @@  F: app/test/test_lpm*
 F: app/test/test_func_reentrancy.c
 F: app/test/test_xmmt_ops.h
 
+Memarea - EXPERIMENTAL
+M: Chengwen Feng <fengchengwen@huawei.com>
+F: lib/memarea
+F: doc/guides/prog_guide/memarea_lib.rst
+
 Membership - EXPERIMENTAL
 M: Yipeng Wang <yipeng1.wang@intel.com>
 M: Sameh Gobriel <sameh.gobriel@intel.com>
diff --git a/doc/api/doxy-api-index.md b/doc/api/doxy-api-index.md
index de488c7abf..24456604f8 100644
--- a/doc/api/doxy-api-index.md
+++ b/doc/api/doxy-api-index.md
@@ -62,7 +62,8 @@  The public API headers are grouped by topics:
   [memzone](@ref rte_memzone.h),
   [mempool](@ref rte_mempool.h),
   [malloc](@ref rte_malloc.h),
-  [memcpy](@ref rte_memcpy.h)
+  [memcpy](@ref rte_memcpy.h),
+  [memarea](@ref rte_memarea.h)
 
 - **timers**:
   [cycles](@ref rte_cycles.h),
diff --git a/doc/api/doxy-api.conf.in b/doc/api/doxy-api.conf.in
index f0886c3bd1..8334ebcbd6 100644
--- a/doc/api/doxy-api.conf.in
+++ b/doc/api/doxy-api.conf.in
@@ -53,6 +53,7 @@  INPUT                   = @TOPDIR@/doc/api/doxy-api-index.md \
                           @TOPDIR@/lib/latencystats \
                           @TOPDIR@/lib/lpm \
                           @TOPDIR@/lib/mbuf \
+                          @TOPDIR@/lib/memarea \
                           @TOPDIR@/lib/member \
                           @TOPDIR@/lib/mempool \
                           @TOPDIR@/lib/meter \
diff --git a/doc/guides/prog_guide/index.rst b/doc/guides/prog_guide/index.rst
index 8564883018..e9015d65e3 100644
--- a/doc/guides/prog_guide/index.rst
+++ b/doc/guides/prog_guide/index.rst
@@ -37,6 +37,7 @@  Programmer's Guide
     hash_lib
     toeplitz_hash_lib
     efd_lib
+    memarea_lib
     member_lib
     lpm_lib
     lpm6_lib
diff --git a/doc/guides/prog_guide/memarea_lib.rst b/doc/guides/prog_guide/memarea_lib.rst
new file mode 100644
index 0000000000..b96dad15f6
--- /dev/null
+++ b/doc/guides/prog_guide/memarea_lib.rst
@@ -0,0 +1,39 @@ 
+..  SPDX-License-Identifier: BSD-3-Clause
+    Copyright(c) 2022 HiSilicon Limited
+
+Memarea Library
+===============
+
+Introduction
+------------
+
+The memarea library provides an allocator of variable-size objects, it is
+oriented towards the application layer, which could provides 'region-based
+memory management' function [1].
+
+The main features are as follows:
+
+* The default aligement size is ``RTE_CACHE_LINE_SIZE``.
+
+* The memory region can be initialized from the following memory sources:
+  a) RTE memory: e.g. invoke ``rte_malloc_socket`` to obtain. b) System API:
+  e.g. invoke posix_memalign to obtain. c) User provided address: it can be from
+  extendedd memory as long as it is available. d) User provided memarea: it can
+  be from another memarea.
+
+* It provides refcnt feature which could be useful in multi-reader scenario.
+
+* It supports MT-safe as long as it's specified at creation time.
+
+Library API Overview
+--------------------
+
+The ``rte_memarea_create()`` function is used to create a memarea, the function
+returns the pointer to the created memarea or ``NULL`` if the creation failed.
+
+The ``rte_memarea_destroy()`` function is used to destroy a memarea.
+
+Reference
+---------
+
+[1] https://en.wikipedia.org/wiki/Region-based_memory_management
diff --git a/doc/guides/rel_notes/release_22_11.rst b/doc/guides/rel_notes/release_22_11.rst
index 5d8ef669b8..4c1f760b98 100644
--- a/doc/guides/rel_notes/release_22_11.rst
+++ b/doc/guides/rel_notes/release_22_11.rst
@@ -55,6 +55,12 @@  New Features
      Also, make sure to start the actual text at the margin.
      =======================================================
 
+* **Added memarea library.**
+
+  The memarea library is an allocator of variable-size objects, it is oriented
+  towards the application layer, which could provides 'region-based memory
+  management' function.
+
 * **Added configuration for asynchronous flow connection tracking.**
 
   Added connection tracking action number hint to ``rte_flow_configure``
diff --git a/lib/eal/common/eal_common_log.c b/lib/eal/common/eal_common_log.c
index bd7b188ceb..3d62af59c6 100644
--- a/lib/eal/common/eal_common_log.c
+++ b/lib/eal/common/eal_common_log.c
@@ -369,6 +369,7 @@  static const struct logtype logtype_strings[] = {
 	{RTE_LOGTYPE_EFD,        "lib.efd"},
 	{RTE_LOGTYPE_EVENTDEV,   "lib.eventdev"},
 	{RTE_LOGTYPE_GSO,        "lib.gso"},
+	{RTE_LOGTYPE_MEMAREA,    "lib.memarea"},
 	{RTE_LOGTYPE_USER1,      "user1"},
 	{RTE_LOGTYPE_USER2,      "user2"},
 	{RTE_LOGTYPE_USER3,      "user3"},
diff --git a/lib/eal/include/rte_log.h b/lib/eal/include/rte_log.h
index 25ce42cdfc..708f3a39dd 100644
--- a/lib/eal/include/rte_log.h
+++ b/lib/eal/include/rte_log.h
@@ -48,6 +48,7 @@  extern "C" {
 #define RTE_LOGTYPE_EFD       18 /**< Log related to EFD. */
 #define RTE_LOGTYPE_EVENTDEV  19 /**< Log related to eventdev. */
 #define RTE_LOGTYPE_GSO       20 /**< Log related to GSO. */
+#define RTE_LOGTYPE_MEMAREA   21 /**< Log related to memarea. */
 
 /* these log types can be used in an application */
 #define RTE_LOGTYPE_USER1     24 /**< User-defined log type 1. */
diff --git a/lib/memarea/memarea_private.h b/lib/memarea/memarea_private.h
new file mode 100644
index 0000000000..c76392d3e6
--- /dev/null
+++ b/lib/memarea/memarea_private.h
@@ -0,0 +1,30 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2022 HiSilicon Limited
+ */
+
+#ifndef MEMAREA_PRIVATE_H
+#define MEMAREA_PRIVATE_H
+
+#include <rte_memarea.h>
+
+#define MEMAREA_FREE_ELEM_COOKIE	0xFFFFFFFF
+
+struct memarea_elem {
+	size_t   size;
+	uint32_t cookie;
+	int32_t  refcnt; /* Non-zero indicates that it has been allocated */
+	TAILQ_ENTRY(memarea_elem) elem_node;
+	TAILQ_ENTRY(memarea_elem) free_node;
+} __rte_cache_aligned;
+
+TAILQ_HEAD(memarea_elem_list, memarea_elem);
+
+struct rte_memarea {
+	struct rte_memarea_param init;
+	rte_spinlock_t           lock;
+	void                    *area_addr;
+	struct memarea_elem_list elem_list;
+	struct memarea_elem_list free_list;
+} __rte_cache_aligned;
+
+#endif /* MEMAREA_PRIVATE_H */
diff --git a/lib/memarea/meson.build b/lib/memarea/meson.build
new file mode 100644
index 0000000000..0a74fb4cd1
--- /dev/null
+++ b/lib/memarea/meson.build
@@ -0,0 +1,16 @@ 
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2022 HiSilicon Limited
+
+if is_windows
+    build = false
+    reason = 'not supported on Windows'
+    subdir_done()
+endif
+
+sources = files(
+        'rte_memarea.c',
+)
+headers = files(
+        'rte_memarea.h',
+)
+deps += []
diff --git a/lib/memarea/rte_memarea.c b/lib/memarea/rte_memarea.c
new file mode 100644
index 0000000000..868da7661d
--- /dev/null
+++ b/lib/memarea/rte_memarea.c
@@ -0,0 +1,157 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2022 HiSilicon Limited
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <rte_common.h>
+#include <rte_log.h>
+#include <rte_malloc.h>
+#include <rte_spinlock.h>
+
+#include "rte_memarea.h"
+#include "memarea_private.h"
+
+static int
+memarea_check_param(const struct rte_memarea_param *init)
+{
+	size_t len;
+
+	if (init == NULL) {
+		RTE_LOG(ERR, MEMAREA, "memarea init param is NULL!\n");
+		return -EINVAL;
+	}
+
+	len = strnlen(init->name, RTE_MEMAREA_NAMESIZE);
+	if (len == 0 || len >= RTE_MEMAREA_NAMESIZE) {
+		RTE_LOG(ERR, MEMAREA, "memarea name size %zu invalid!\n", len);
+		return -EINVAL;
+	}
+
+	if (init->source != RTE_MEMAREA_SOURCE_RTE_MEMORY &&
+	    init->source != RTE_MEMAREA_SOURCE_SYSTEM_API &&
+	    init->source != RTE_MEMAREA_SOURCE_USER_ADDR &&
+	    init->source != RTE_MEMAREA_SOURCE_USER_MEMAREA) {
+		RTE_LOG(ERR, MEMAREA, "memarea: %s source: %d not supported!\n",
+			init->name, init->source);
+		return -EINVAL;
+	}
+
+	if (init->total_sz <= sizeof(struct memarea_elem)) {
+		RTE_LOG(ERR, MEMAREA, "memarea: %s total-size: %zu too small!\n",
+			init->name, init->total_sz);
+		return -EINVAL;
+	}
+
+	if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR && init->user_addr == NULL) {
+		RTE_LOG(ERR, MEMAREA, "memarea: %s user provided addr is NULL!\n", init->name);
+		return -EINVAL;
+	}
+
+	if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR &&
+	    ((uintptr_t)init->user_addr & (RTE_CACHE_LINE_SIZE - 1))) {
+		RTE_LOG(ERR, MEMAREA, "memarea: %s user provided addr should align: %d!\n",
+			init->name, RTE_CACHE_LINE_SIZE);
+		return -EINVAL;
+	}
+
+	if (init->source == RTE_MEMAREA_SOURCE_USER_MEMAREA && init->user_memarea == NULL) {
+		RTE_LOG(ERR, MEMAREA, "memarea: %s user provided memarea is NULL!\n", init->name);
+		return -EINVAL;
+	}
+
+	if (init->alg != RTE_MEMAREA_ALG_DEFAULT) {
+		RTE_LOG(ERR, MEMAREA, "memarea: %s alg: %d not supported!\n",
+			init->name, init->alg);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void *
+memarea_alloc_from_system_api(size_t size)
+{
+	void *ptr = NULL;
+	int ret;
+
+	ret = posix_memalign(&ptr, RTE_CACHE_LINE_SIZE, size);
+	if (ret)
+		return NULL;
+	return ptr;
+}
+
+static void *
+memarea_alloc_area(const struct rte_memarea_param *init)
+{
+	void *ptr = NULL;
+
+	if (init->source == RTE_MEMAREA_SOURCE_RTE_MEMORY)
+		ptr = rte_malloc_socket(NULL, init->total_sz, RTE_CACHE_LINE_SIZE,
+					init->numa_socket);
+	else if (init->source == RTE_MEMAREA_SOURCE_SYSTEM_API)
+		ptr = memarea_alloc_from_system_api(init->total_sz);
+	else if (init->source == RTE_MEMAREA_SOURCE_USER_ADDR)
+		ptr = init->user_addr;
+
+	if (ptr == NULL)
+		RTE_LOG(ERR, MEMAREA, "memarea: %s alloc memory area fail!\n", init->name);
+
+	return ptr;
+}
+
+struct rte_memarea *
+rte_memarea_create(const struct rte_memarea_param *init)
+{
+	struct memarea_elem *elem;
+	struct rte_memarea *ma;
+	void *addr;
+	int ret;
+
+	ret = memarea_check_param(init);
+	if (ret)
+		return NULL;
+
+	addr = memarea_alloc_area(init);
+	if (addr == NULL)
+		return NULL;
+
+	ma = rte_zmalloc(NULL, sizeof(struct rte_memarea), RTE_CACHE_LINE_SIZE);
+	if (ma == NULL) {
+		RTE_LOG(ERR, MEMAREA, "malloc memarea: %s management obj fail!\n", init->name);
+		return NULL;
+	}
+
+	ma->init = *init;
+	rte_spinlock_init(&ma->lock);
+	TAILQ_INIT(&ma->elem_list);
+	TAILQ_INIT(&ma->free_list);
+	ma->area_addr = addr;
+	elem = addr;
+	elem->size = init->total_sz - sizeof(struct memarea_elem);
+	elem->cookie = MEMAREA_FREE_ELEM_COOKIE;
+	elem->refcnt = 0;
+	TAILQ_INSERT_TAIL(&ma->elem_list, elem, elem_node);
+	TAILQ_INSERT_TAIL(&ma->free_list, elem, free_node);
+
+	return ma;
+}
+
+static void
+memarea_free_area(struct rte_memarea *ma)
+{
+	if (ma->init.source == RTE_MEMAREA_SOURCE_RTE_MEMORY)
+		rte_free(ma->area_addr);
+	else if (ma->init.source == RTE_MEMAREA_SOURCE_SYSTEM_API)
+		free(ma->area_addr);
+}
+
+void
+rte_memarea_destroy(struct rte_memarea *ma)
+{
+	if (ma == NULL)
+		return;
+	memarea_free_area(ma);
+	rte_free(ma);
+}
diff --git a/lib/memarea/rte_memarea.h b/lib/memarea/rte_memarea.h
new file mode 100644
index 0000000000..543cda4cac
--- /dev/null
+++ b/lib/memarea/rte_memarea.h
@@ -0,0 +1,145 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2022 HiSilicon Limited
+ */
+
+#ifndef RTE_MEMAREA_H
+#define RTE_MEMAREA_H
+
+/**
+ * @file
+ * RTE Memarea.
+ *
+ * The memarea is an allocator of variable-size object which based on a memory
+ * region. It has the following features:
+ *
+ * - The default alignment size is RTE_CACHE_LINE_SIZE.
+ * - The memory region can be initialized from the following memory sources:
+ *   1. RTE memory: e.g. invoke rte_malloc_socket to obtain.
+ *   2. System API: e.g. invoke posix_memalign to obtain.
+ *   3. User provided address: it can be from extended memory as long as it is
+ *      available. The address must be aligned to RTE_CACHE_LINE_SIZE.
+ *   4) User provided memarea: it can be from another memarea. So we can build
+ *      the following memory management structure:
+ *         \code{.unparsed}
+ *                           -------------
+ *                           | memarea-1 |
+ *                           -------------
+ *                                 |
+ *                                 v
+ *                  -------------------------------
+ *                  |               |             |
+ *                  v               v             v
+ *            -------------   -------------   ----------
+ *            | memarea-2 |   | memarea-3 |   | object |
+ *            -------------   -------------   ----------
+ *         \endcode
+ *      As shown above, the memarea-2/3 both create from memarea-1's memory.
+ * - It provides refcnt feature which could be useful in multi-reader scenario.
+ * - It supports MT-safe as long as it's specified at creation time. If not
+ *   specified, all the functions of the memarea API are lock-free, and assume
+ *   to not be invoked in parallel on different logical cores to work on the
+ *   same memarea.
+ */
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include <rte_compat.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define RTE_MEMAREA_NAMESIZE	64
+
+/**
+ * Memarea memory source.
+ */
+enum rte_memarea_source {
+	/** Memory source comes from rte memory. */
+	RTE_MEMAREA_SOURCE_RTE_MEMORY,
+	/** Memory source comes from system API. */
+	RTE_MEMAREA_SOURCE_SYSTEM_API,
+	/** Memory source comes from user-provided address. */
+	RTE_MEMAREA_SOURCE_USER_ADDR,
+	/** Memory source comes from user-provided memarea. */
+	RTE_MEMAREA_SOURCE_USER_MEMAREA,
+};
+
+/**
+ * Memarea memory management algorithm.
+ */
+enum rte_memarea_alg {
+	/* The default management algorithm is a variant of the next fit
+	 * algorithm. It uses a free-list to apply for memory and uses an
+	 * element-list in ascending order of address to support merging
+	 * upon free.
+	 */
+	RTE_MEMAREA_ALG_DEFAULT,
+};
+
+struct rte_memarea;
+
+struct rte_memarea_param {
+	char name[RTE_MEMAREA_NAMESIZE]; /**< Name of memarea. */
+	enum rte_memarea_source source;  /**< Memory source of memarea. */
+	enum rte_memarea_alg alg;        /**< Memory management algorithm. */
+	size_t total_sz;                 /**< total size (bytes) of memarea. */
+	/** Indicates whether the memarea API should be MT-safe. */
+	uint32_t mt_safe : 1;
+	union {
+		/** Numa socket from which to apply for memarea's memory, this
+		 * field is valid only when the source is set to be
+		 * RTE_MEMAREA_SOURCE_RTE_MEMORY.
+		 */
+		int numa_socket;
+		/** User provided address, this field is valid only when the
+		 * source is set to be RTE_MEMAREA_SOURCE_USER_ADDR.
+		 * Note: the provided address must align at least
+		 * RTE_CACHE_LINE_SIZE.
+		 */
+		void *user_addr;
+		/** User provided memarea, this field is valid only when the
+		 * source is set to be RTE_MEMAREA_SOURCE_USER_MEMAREA.
+		 */
+		struct rte_memarea *user_memarea;
+	};
+};
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Create memarea.
+ *
+ * Create one new memarea.
+ *
+ * @param init
+ *   The init parameter of memarea.
+ *
+ * @return
+ *   Non-NULL on success. Otherwise NULL is returned.
+ */
+__rte_experimental
+struct rte_memarea *rte_memarea_create(const struct rte_memarea_param *init);
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Destroy memarea.
+ *
+ * Destroy the memarea.
+ *
+ * @param ma
+ *   The pointer of memarea.
+ */
+__rte_experimental
+void rte_memarea_destroy(struct rte_memarea *ma);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* RTE_MEMAREA_H */
diff --git a/lib/memarea/version.map b/lib/memarea/version.map
new file mode 100644
index 0000000000..f36a04d7cf
--- /dev/null
+++ b/lib/memarea/version.map
@@ -0,0 +1,12 @@ 
+EXPERIMENTAL {
+	global:
+
+	rte_memarea_create;
+	rte_memarea_destroy;
+
+	local: *;
+};
+
+INTERNAL {
+	local: *;
+};
diff --git a/lib/meson.build b/lib/meson.build
index c648f7d800..521a25d6c0 100644
--- a/lib/meson.build
+++ b/lib/meson.build
@@ -42,6 +42,7 @@  libraries = [
         'kni',
         'latencystats',
         'lpm',
+        'memarea',
         'member',
         'pcapng',
         'power',