[dpdk-dev] [PATCH 05/40] pipeline: add extern objects and functions

[Cristian Dumitrescu <cristian.dumitrescu@intel.com>]

Add extern objects and functions to plug in functions that cannot be
efficiently implemented with existing instructions, e.g. special
checksum/ECC, crypto, meters, stats arrays, heuristics, etc. In/out
arguments are passed through mailbox with format defined by struct.

Signed-off-by: Cristian Dumitrescu <cristian.dumitrescu@intel.com>
---
 lib/librte_pipeline/Makefile                 |   1 +
 lib/librte_pipeline/meson.build              |   3 +-
 lib/librte_pipeline/rte_pipeline_version.map |   4 +
 lib/librte_pipeline/rte_swx_extern.h         |  98 ++++
 lib/librte_pipeline/rte_swx_pipeline.c       | 477 +++++++++++++++++++
 lib/librte_pipeline/rte_swx_pipeline.h       | 113 +++++
 6 files changed, 695 insertions(+), 1 deletion(-)
 create mode 100644 lib/librte_pipeline/rte_swx_extern.h

diff --git a/lib/librte_pipeline/Makefile b/lib/librte_pipeline/Makefile
index 32582db9e..23bfd88e6 100644
--- a/lib/librte_pipeline/Makefile
+++ b/lib/librte_pipeline/Makefile
@@ -25,6 +25,7 @@ SRCS-$(CONFIG_RTE_LIBRTE_PIPELINE) += rte_swx_pipeline.c
 
 # install includes
 SYMLINK-$(CONFIG_RTE_LIBRTE_PIPELINE)-include += rte_pipeline.h rte_port_in_action.h rte_table_action.h
+SYMLINK-$(CONFIG_RTE_LIBRTE_PIPELINE)-include += rte_swx_extern.h
 SYMLINK-$(CONFIG_RTE_LIBRTE_PIPELINE)-include += rte_swx_pipeline.h
 
 include $(RTE_SDK)/mk/rte.lib.mk
diff --git a/lib/librte_pipeline/meson.build b/lib/librte_pipeline/meson.build
index 880c2b274..bea406848 100644
--- a/lib/librte_pipeline/meson.build
+++ b/lib/librte_pipeline/meson.build
@@ -8,5 +8,6 @@ sources = files('rte_pipeline.c',
 headers = files('rte_pipeline.h',
 	'rte_port_in_action.h',
 	'rte_table_action.h',
-	'rte_swx_pipeline.h',)
+	'rte_swx_pipeline.h',
+	'rte_swx_extern.h',)
 deps += ['port', 'table', 'meter', 'sched', 'cryptodev']
diff --git a/lib/librte_pipeline/rte_pipeline_version.map b/lib/librte_pipeline/rte_pipeline_version.map
index 6a48c3666..4297e185d 100644
--- a/lib/librte_pipeline/rte_pipeline_version.map
+++ b/lib/librte_pipeline/rte_pipeline_version.map
@@ -60,6 +60,10 @@ EXPERIMENTAL {
 	rte_swx_pipeline_port_in_config;
 	rte_swx_pipeline_port_out_type_register;
 	rte_swx_pipeline_port_out_config;
+	rte_swx_pipeline_extern_type_register;
+	rte_swx_pipeline_extern_type_member_func_register;
+	rte_swx_pipeline_extern_object_config;
+	rte_swx_pipeline_extern_func_register;
 	rte_swx_pipeline_struct_type_register;
 	rte_swx_pipeline_packet_header_register;
 	rte_swx_pipeline_packet_metadata_register;
diff --git a/lib/librte_pipeline/rte_swx_extern.h b/lib/librte_pipeline/rte_swx_extern.h
new file mode 100644
index 000000000..e10e963d6
--- /dev/null
+++ b/lib/librte_pipeline/rte_swx_extern.h
@@ -0,0 +1,98 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2020 Intel Corporation
+ */
+#ifndef __INCLUDE_RTE_SWX_EXTERN_H__
+#define __INCLUDE_RTE_SWX_EXTERN_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @file
+ * RTE SWX Extern objects and functions
+ *
+ * Extern object and extern function interfaces. The extern objects and extern
+ * functions provide the mechanisms to hook external functionality into the
+ * packet processing pipeline.
+ */
+
+#include <stdint.h>
+
+/*
+ * Extern type
+ */
+
+/**
+ * Extern object constructor
+ *
+ * @param[in] args
+ *   Extern object constructor arguments. It may be NULL.
+ * @return
+ *   Extern object handle.
+ */
+typedef void *
+(*rte_swx_extern_type_constructor_t)(const char *args);
+
+/**
+ * Extern object destructor
+ *
+ * @param[in] object
+ *   Extern object handle.
+ */
+typedef void
+(*rte_swx_extern_type_destructor_t)(void *object);
+
+/**
+ * Extern object member function
+ *
+ * The mailbox is used to pass input arguments to the member function and
+ * retrieve the output results. The mailbox mechanism allows for multiple
+ * concurrent executions of the same member function for the same extern object.
+ *
+ * Multiple invocations of the same member function may be required in order for
+ * the associated operation to complete. The completion is flagged by a return
+ * value of 1, in which case the results are available in the mailbox; in case
+ * of a return value of 0, the operation is not yet completed, so the member
+ * function must be invoked again with exactly the same object and mailbox
+ * arguments.
+ *
+ * @param[in] object
+ *   Extern object handle.
+ * @param[in] mailbox
+ *   Extern object mailbox.
+ * @return
+ *   0 when the operation is not yet completed, and 1 when the operation is
+ *   completed. No other return values are allowed.
+ */
+typedef int
+(*rte_swx_extern_type_member_func_t)(void *object, void *mailbox);
+
+/*
+ * Extern function
+ */
+
+/** The mailbox is used to pass input arguments to the extern function and
+ * retrieve the output results. The mailbox mechanism allows for multiple
+ * concurrent executions of the same extern function.
+ *
+ * Multiple invocations of the same extern function may be required in order for
+ * the associated operation to complete. The completion is flagged by a return
+ * value of 1, in which case the results are available in the mailbox; in case
+ * of a return value of 0, the operation is not yet completed, so the extern
+ * function must be invoked again with exactly the same mailbox argument.
+ *
+ * @param[in] mailbox
+ *   Extern object mailbox.
+ * @return
+ *   0 when the operation is not yet completed, and 1 when the operation is
+ *   completed. No other return values are allowed.
+ */
+typedef int
+(*rte_swx_extern_func_t)(void *mailbox);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/lib/librte_pipeline/rte_swx_pipeline.c b/lib/librte_pipeline/rte_swx_pipeline.c
index cb2e32b83..2335831bf 100644
--- a/lib/librte_pipeline/rte_swx_pipeline.c
+++ b/lib/librte_pipeline/rte_swx_pipeline.c
@@ -90,6 +90,70 @@ struct port_out_runtime {
 	void *obj;
 };
 
+/*
+ * Extern object.
+ */
+struct extern_type_member_func {
+	TAILQ_ENTRY(extern_type_member_func) node;
+	char name[RTE_SWX_NAME_SIZE];
+	rte_swx_extern_type_member_func_t func;
+	uint32_t id;
+};
+
+TAILQ_HEAD(extern_type_member_func_tailq, extern_type_member_func);
+
+struct extern_type {
+	TAILQ_ENTRY(extern_type) node;
+	char name[RTE_SWX_NAME_SIZE];
+	struct struct_type *mailbox_struct_type;
+	rte_swx_extern_type_constructor_t constructor;
+	rte_swx_extern_type_destructor_t destructor;
+	struct extern_type_member_func_tailq funcs;
+	uint32_t n_funcs;
+};
+
+TAILQ_HEAD(extern_type_tailq, extern_type);
+
+struct extern_obj {
+	TAILQ_ENTRY(extern_obj) node;
+	char name[RTE_SWX_NAME_SIZE];
+	struct extern_type *type;
+	void *obj;
+	uint32_t struct_id;
+	uint32_t id;
+};
+
+TAILQ_HEAD(extern_obj_tailq, extern_obj);
+
+#ifndef RTE_SWX_EXTERN_TYPE_MEMBER_FUNCS_MAX
+#define RTE_SWX_EXTERN_TYPE_MEMBER_FUNCS_MAX 8
+#endif
+
+struct extern_obj_runtime {
+	void *obj;
+	uint8_t *mailbox;
+	rte_swx_extern_type_member_func_t funcs[RTE_SWX_EXTERN_TYPE_MEMBER_FUNCS_MAX];
+};
+
+/*
+ * Extern function.
+ */
+struct extern_func {
+	TAILQ_ENTRY(extern_func) node;
+	char name[RTE_SWX_NAME_SIZE];
+	struct struct_type *mailbox_struct_type;
+	rte_swx_extern_func_t func;
+	uint32_t struct_id;
+	uint32_t id;
+};
+
+TAILQ_HEAD(extern_func_tailq, extern_func);
+
+struct extern_func_runtime {
+	uint8_t *mailbox;
+	rte_swx_extern_func_t func;
+};
+
 /*
  * Header.
  */
@@ -130,6 +194,10 @@ struct thread {
 
 	/* Packet meta-data. */
 	uint8_t *metadata;
+
+	/* Extern objects and functions. */
+	struct extern_obj_runtime *extern_objs;
+	struct extern_func_runtime *extern_funcs;
 };
 
 #ifndef RTE_SWX_PIPELINE_THREADS_MAX
@@ -142,6 +210,9 @@ struct rte_swx_pipeline {
 	struct port_in_tailq ports_in;
 	struct port_out_type_tailq port_out_types;
 	struct port_out_tailq ports_out;
+	struct extern_type_tailq extern_types;
+	struct extern_obj_tailq extern_objs;
+	struct extern_func_tailq extern_funcs;
 	struct header_tailq headers;
 	struct struct_type *metadata_st;
 	uint32_t metadata_struct_id;
@@ -153,6 +224,8 @@ struct rte_swx_pipeline {
 	uint32_t n_structs;
 	uint32_t n_ports_in;
 	uint32_t n_ports_out;
+	uint32_t n_extern_objs;
+	uint32_t n_extern_funcs;
 	uint32_t n_headers;
 	int build_done;
 	int numa_node;
@@ -606,6 +679,395 @@ port_out_free(struct rte_swx_pipeline *p)
 	}
 }
 
+/*
+ * Extern object.
+ */
+static struct extern_type *
+extern_type_find(struct rte_swx_pipeline *p, const char *name)
+{
+	struct extern_type *elem;
+
+	TAILQ_FOREACH(elem, &p->extern_types, node)
+		if (strcmp(elem->name, name) == 0)
+			return elem;
+
+	return NULL;
+}
+
+static struct extern_type_member_func *
+extern_type_member_func_find(struct extern_type *type, const char *name)
+{
+	struct extern_type_member_func *elem;
+
+	TAILQ_FOREACH(elem, &type->funcs, node)
+		if (strcmp(elem->name, name) == 0)
+			return elem;
+
+	return NULL;
+}
+
+static struct extern_obj *
+extern_obj_find(struct rte_swx_pipeline *p, const char *name)
+{
+	struct extern_obj *elem;
+
+	TAILQ_FOREACH(elem, &p->extern_objs, node)
+		if (strcmp(elem->name, name) == 0)
+			return elem;
+
+	return NULL;
+}
+
+int
+rte_swx_pipeline_extern_type_register(struct rte_swx_pipeline *p,
+	const char *name,
+	const char *mailbox_struct_type_name,
+	rte_swx_extern_type_constructor_t constructor,
+	rte_swx_extern_type_destructor_t destructor)
+{
+	struct extern_type *elem;
+	struct struct_type *mailbox_struct_type;
+
+	CHECK(p, EINVAL);
+
+	CHECK_NAME(name, EINVAL);
+	CHECK(!extern_type_find(p, name), EEXIST);
+
+	CHECK_NAME(mailbox_struct_type_name, EINVAL);
+	mailbox_struct_type = struct_type_find(p, mailbox_struct_type_name);
+	CHECK(mailbox_struct_type, EINVAL);
+
+	CHECK(constructor, EINVAL);
+	CHECK(destructor, EINVAL);
+
+	/* Node allocation. */
+	elem = calloc(1, sizeof(struct extern_type));
+	CHECK(elem, ENOMEM);
+
+	/* Node initialization. */
+	strcpy(elem->name, name);
+	elem->mailbox_struct_type = mailbox_struct_type;
+	elem->constructor = constructor;
+	elem->destructor = destructor;
+	TAILQ_INIT(&elem->funcs);
+
+	/* Node add to tailq. */
+	TAILQ_INSERT_TAIL(&p->extern_types, elem, node);
+
+	return 0;
+}
+
+int
+rte_swx_pipeline_extern_type_member_func_register(struct rte_swx_pipeline *p,
+	const char *extern_type_name,
+	const char *name,
+	rte_swx_extern_type_member_func_t member_func)
+{
+	struct extern_type *type;
+	struct extern_type_member_func *type_member;
+
+	CHECK(p, EINVAL);
+
+	CHECK(extern_type_name, EINVAL);
+	type = extern_type_find(p, extern_type_name);
+	CHECK(type, EINVAL);
+	CHECK(type->n_funcs < RTE_SWX_EXTERN_TYPE_MEMBER_FUNCS_MAX, ENOSPC);
+
+	CHECK(name, EINVAL);
+	CHECK(!extern_type_member_func_find(type, name), EEXIST);
+
+	CHECK(member_func, EINVAL);
+
+	/* Node allocation. */
+	type_member = calloc(1, sizeof(struct extern_type_member_func));
+	CHECK(type_member, ENOMEM);
+
+	/* Node initialization. */
+	strcpy(type_member->name, name);
+	type_member->func = member_func;
+	type_member->id = type->n_funcs;
+
+	/* Node add to tailq. */
+	TAILQ_INSERT_TAIL(&type->funcs, type_member, node);
+	type->n_funcs++;
+
+	return 0;
+}
+
+int
+rte_swx_pipeline_extern_object_config(struct rte_swx_pipeline *p,
+				      const char *extern_type_name,
+				      const char *name,
+				      const char *args)
+{
+	struct extern_type *type;
+	struct extern_obj *obj;
+	void *obj_handle;
+
+	CHECK(p, EINVAL);
+
+	CHECK_NAME(extern_type_name, EINVAL);
+	type = extern_type_find(p, extern_type_name);
+	CHECK(type, EINVAL);
+
+	CHECK_NAME(name, EINVAL);
+	CHECK(!extern_obj_find(p, name), EEXIST);
+
+	/* Node allocation. */
+	obj = calloc(1, sizeof(struct extern_obj));
+	CHECK(obj, ENOMEM);
+
+	/* Object construction. */
+	obj_handle = type->constructor(args);
+	if (!obj_handle) {
+		free(obj);
+		CHECK(0, ENODEV);
+	}
+
+	/* Node initialization. */
+	strcpy(obj->name, name);
+	obj->type = type;
+	obj->obj = obj_handle;
+	obj->struct_id = p->n_structs;
+	obj->id = p->n_extern_objs;
+
+	/* Node add to tailq. */
+	TAILQ_INSERT_TAIL(&p->extern_objs, obj, node);
+	p->n_extern_objs++;
+	p->n_structs++;
+
+	return 0;
+}
+
+static int
+extern_obj_build(struct rte_swx_pipeline *p)
+{
+	uint32_t i;
+
+	for (i = 0; i < RTE_SWX_PIPELINE_THREADS_MAX; i++) {
+		struct thread *t = &p->threads[i];
+		struct extern_obj *obj;
+
+		t->extern_objs = calloc(p->n_extern_objs,
+					sizeof(struct extern_obj_runtime));
+		CHECK(t->extern_objs, ENOMEM);
+
+		TAILQ_FOREACH(obj, &p->extern_objs, node) {
+			struct extern_obj_runtime *r =
+				&t->extern_objs[obj->id];
+			struct extern_type_member_func *func;
+			uint32_t mailbox_size =
+				obj->type->mailbox_struct_type->n_bits / 8;
+
+			r->obj = obj->obj;
+
+			r->mailbox = calloc(1, mailbox_size);
+			CHECK(r->mailbox, ENOMEM);
+
+			TAILQ_FOREACH(func, &obj->type->funcs, node)
+				r->funcs[func->id] = func->func;
+
+			t->structs[obj->struct_id] = r->mailbox;
+		}
+	}
+
+	return 0;
+}
+
+static void
+extern_obj_build_free(struct rte_swx_pipeline *p)
+{
+	uint32_t i;
+
+	for (i = 0; i < RTE_SWX_PIPELINE_THREADS_MAX; i++) {
+		struct thread *t = &p->threads[i];
+		uint32_t j;
+
+		if (!t->extern_objs)
+			continue;
+
+		for (j = 0; j < p->n_extern_objs; j++) {
+			struct extern_obj_runtime *r = &t->extern_objs[j];
+
+			free(r->mailbox);
+		}
+
+		free(t->extern_objs);
+		t->extern_objs = NULL;
+	}
+}
+
+static void
+extern_obj_free(struct rte_swx_pipeline *p)
+{
+	extern_obj_build_free(p);
+
+	/* Extern objects. */
+	for ( ; ; ) {
+		struct extern_obj *elem;
+
+		elem = TAILQ_FIRST(&p->extern_objs);
+		if (!elem)
+			break;
+
+		TAILQ_REMOVE(&p->extern_objs, elem, node);
+		if (elem->obj)
+			elem->type->destructor(elem->obj);
+		free(elem);
+	}
+
+	/* Extern types. */
+	for ( ; ; ) {
+		struct extern_type *elem;
+
+		elem = TAILQ_FIRST(&p->extern_types);
+		if (!elem)
+			break;
+
+		TAILQ_REMOVE(&p->extern_types, elem, node);
+
+		for ( ; ; ) {
+			struct extern_type_member_func *func;
+
+			func = TAILQ_FIRST(&elem->funcs);
+			if (!func)
+				break;
+
+			TAILQ_REMOVE(&elem->funcs, func, node);
+			free(func);
+		}
+
+		free(elem);
+	}
+}
+
+/*
+ * Extern function.
+ */
+static struct extern_func *
+extern_func_find(struct rte_swx_pipeline *p, const char *name)
+{
+	struct extern_func *elem;
+
+	TAILQ_FOREACH(elem, &p->extern_funcs, node)
+		if (strcmp(elem->name, name) == 0)
+			return elem;
+
+	return NULL;
+}
+
+int
+rte_swx_pipeline_extern_func_register(struct rte_swx_pipeline *p,
+				      const char *name,
+				      const char *mailbox_struct_type_name,
+				      rte_swx_extern_func_t func)
+{
+	struct extern_func *f;
+	struct struct_type *mailbox_struct_type;
+
+	CHECK(p, EINVAL);
+
+	CHECK_NAME(name, EINVAL);
+	CHECK(!extern_func_find(p, name), EEXIST);
+
+	CHECK_NAME(mailbox_struct_type_name, EINVAL);
+	mailbox_struct_type = struct_type_find(p, mailbox_struct_type_name);
+	CHECK(mailbox_struct_type, EINVAL);
+
+	CHECK(func, EINVAL);
+
+	/* Node allocation. */
+	f = calloc(1, sizeof(struct extern_func));
+	CHECK(func, ENOMEM);
+
+	/* Node initialization. */
+	strcpy(f->name, name);
+	f->mailbox_struct_type = mailbox_struct_type;
+	f->func = func;
+	f->struct_id = p->n_structs;
+	f->id = p->n_extern_funcs;
+
+	/* Node add to tailq. */
+	TAILQ_INSERT_TAIL(&p->extern_funcs, f, node);
+	p->n_extern_funcs++;
+	p->n_structs++;
+
+	return 0;
+}
+
+static int
+extern_func_build(struct rte_swx_pipeline *p)
+{
+	uint32_t i;
+
+	for (i = 0; i < RTE_SWX_PIPELINE_THREADS_MAX; i++) {
+		struct thread *t = &p->threads[i];
+		struct extern_func *func;
+
+		/* Memory allocation. */
+		t->extern_funcs = calloc(p->n_extern_funcs,
+					 sizeof(struct extern_func_runtime));
+		CHECK(t->extern_funcs, ENOMEM);
+
+		/* Extern function. */
+		TAILQ_FOREACH(func, &p->extern_funcs, node) {
+			struct extern_func_runtime *r =
+				&t->extern_funcs[func->id];
+			uint32_t mailbox_size =
+				func->mailbox_struct_type->n_bits / 8;
+
+			r->func = func->func;
+
+			r->mailbox = calloc(1, mailbox_size);
+			CHECK(r->mailbox, ENOMEM);
+
+			t->structs[func->struct_id] = r->mailbox;
+		}
+	}
+
+	return 0;
+}
+
+static void
+extern_func_build_free(struct rte_swx_pipeline *p)
+{
+	uint32_t i;
+
+	for (i = 0; i < RTE_SWX_PIPELINE_THREADS_MAX; i++) {
+		struct thread *t = &p->threads[i];
+		uint32_t j;
+
+		if (!t->extern_funcs)
+			continue;
+
+		for (j = 0; j < p->n_extern_funcs; j++) {
+			struct extern_func_runtime *r = &t->extern_funcs[j];
+
+			free(r->mailbox);
+		}
+
+		free(t->extern_funcs);
+		t->extern_funcs = NULL;
+	}
+}
+
+static void
+extern_func_free(struct rte_swx_pipeline *p)
+{
+	extern_func_build_free(p);
+
+	for ( ; ; ) {
+		struct extern_func *elem;
+
+		elem = TAILQ_FIRST(&p->extern_funcs);
+		if (!elem)
+			break;
+
+		TAILQ_REMOVE(&p->extern_funcs, elem, node);
+		free(elem);
+	}
+}
+
 /*
  * Header.
  */
@@ -826,6 +1288,9 @@ rte_swx_pipeline_config(struct rte_swx_pipeline **p, int numa_node)
 	TAILQ_INIT(&pipeline->ports_in);
 	TAILQ_INIT(&pipeline->port_out_types);
 	TAILQ_INIT(&pipeline->ports_out);
+	TAILQ_INIT(&pipeline->extern_types);
+	TAILQ_INIT(&pipeline->extern_objs);
+	TAILQ_INIT(&pipeline->extern_funcs);
 	TAILQ_INIT(&pipeline->headers);
 
 	pipeline->n_structs = 1; /* Struct 0 is reserved for action_data. */
@@ -843,6 +1308,8 @@ rte_swx_pipeline_free(struct rte_swx_pipeline *p)
 
 	metadata_free(p);
 	header_free(p);
+	extern_func_free(p);
+	extern_obj_free(p);
 	port_out_free(p);
 	port_in_free(p);
 	struct_free(p);
@@ -870,6 +1337,14 @@ rte_swx_pipeline_build(struct rte_swx_pipeline *p)
 	if (status)
 		goto error;
 
+	status = extern_obj_build(p);
+	if (status)
+		goto error;
+
+	status = extern_func_build(p);
+	if (status)
+		goto error;
+
 	status = header_build(p);
 	if (status)
 		goto error;
@@ -884,6 +1359,8 @@ rte_swx_pipeline_build(struct rte_swx_pipeline *p)
 error:
 	metadata_build_free(p);
 	header_build_free(p);
+	extern_func_build_free(p);
+	extern_obj_build_free(p);
 	port_out_build_free(p);
 	port_in_build_free(p);
 	struct_build_free(p);
diff --git a/lib/librte_pipeline/rte_swx_pipeline.h b/lib/librte_pipeline/rte_swx_pipeline.h
index 4a7b679a4..2e8a6cdf8 100644
--- a/lib/librte_pipeline/rte_swx_pipeline.h
+++ b/lib/librte_pipeline/rte_swx_pipeline.h
@@ -19,6 +19,7 @@ extern "C" {
 #include <rte_compat.h>
 
 #include "rte_swx_port.h"
+#include "rte_swx_extern.h"
 
 /** Name size. */
 #ifndef RTE_SWX_NAME_SIZE
@@ -147,6 +148,118 @@ rte_swx_pipeline_port_out_config(struct rte_swx_pipeline *p,
 				 const char *port_type_name,
 				 void *args);
 
+/*
+ * Extern objects and functions
+ */
+
+/**
+ * Pipeline extern type register
+ *
+ * @param[in] p
+ *   Pipeline handle.
+ * @param[in] name
+ *   Extern type name.
+ * @param[in] mailbox_struct_type_name
+ *   Name of existing struct type used to define the mailbox size and layout for
+ *   the extern objects that are instances of this type. Each extern object gets
+ *   its own mailbox, which is used to pass the input arguments to the member
+ *   functions and retrieve the output results.
+ * @param[in] constructor
+ *   Function used to create the extern objects that are instances of this type.
+ * @param[in] destructor
+ *   Function used to free the extern objects that are instances of  this type.
+ * @return
+ *   0 on success or the following error codes otherwise:
+ *   -EINVAL: Invalid argument;
+ *   -ENOMEM: Not enough space/cannot allocate memory;
+ *   -EEXIST: Extern type with this name already exists.
+ */
+__rte_experimental
+int
+rte_swx_pipeline_extern_type_register(struct rte_swx_pipeline *p,
+	const char *name,
+	const char *mailbox_struct_type_name,
+	rte_swx_extern_type_constructor_t constructor,
+	rte_swx_extern_type_destructor_t destructor);
+
+/**
+ * Pipeline extern type member function register
+ *
+ * @param[in] p
+ *   Pipeline handle.
+ * @param[in] extern_type_name
+ *   Existing extern type name.
+ * @param[in] name
+ *   Name for the new member function to be added to the extern type.
+ * @param[in] member_func
+ *   The new member function.
+ * @return
+ *   0 on success or the following error codes otherwise:
+ *   -EINVAL: Invalid argument;
+ *   -ENOMEM: Not enough space/cannot allocate memory;
+ *   -EEXIST: Member function with this name already exists for this type;
+ *   -ENOSPC: Maximum number of member functions reached for this type.
+ */
+__rte_experimental
+int
+rte_swx_pipeline_extern_type_member_func_register(struct rte_swx_pipeline *p,
+	const char *extern_type_name,
+	const char *name,
+	rte_swx_extern_type_member_func_t member_func);
+
+/**
+ * Pipeline extern object configure
+ *
+ * Instantiate a given extern type to create new extern object.
+ *
+ * @param[in] p
+ *   Pipeline handle.
+ * @param[in] extern_type_name
+ *   Existing extern type name.
+ * @param[in] name
+ *   Name for the new object instantiating the extern type.
+ * @param[in] args
+ *   Extern object constructor arguments.
+ * @return
+ *   0 on success or the following error codes otherwise:
+ *   -EINVAL: Invalid argument;
+ *   -ENOMEM: Not enough space/cannot allocate memory;
+ *   -EEXIST: Extern object with this name already exists;
+ *   -ENODEV: Extern object constructor error.
+ */
+__rte_experimental
+int
+rte_swx_pipeline_extern_object_config(struct rte_swx_pipeline *p,
+				      const char *extern_type_name,
+				      const char *name,
+				      const char *args);
+
+/**
+ * Pipeline extern function register
+ *
+ * @param[in] p
+ *   Pipeline handle.
+ * @param[in] name
+ *   Extern function name.
+ * @param[in] mailbox_struct_type_name
+ *   Name of existing struct type used to define the mailbox size and layout for
+ *   this extern function. The mailbox is used to pass the input arguments to
+ *   the extern function and retrieve the output results.
+ * @param[in] func
+ *   The extern function.
+ * @return
+ *   0 on success or the following error codes otherwise:
+ *   -EINVAL: Invalid argument;
+ *   -ENOMEM: Not enough space/cannot allocate memory;
+ *   -EEXIST: Extern function with this name already exists.
+ */
+__rte_experimental
+int
+rte_swx_pipeline_extern_func_register(struct rte_swx_pipeline *p,
+				      const char *name,
+				      const char *mailbox_struct_type_name,
+				      rte_swx_extern_func_t func);
+
 /*
  * Packet headers and meta-data
  */
-- 
2.17.1