Spdk/include/spdk_internal/event.h

/*-
 *   BSD LICENSE
 *
 *   Copyright (c) Intel Corporation.
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
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 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef SPDK_INTERNAL_EVENT_H
#define SPDK_INTERNAL_EVENT_H

#include "spdk/stdinc.h"

#ifdef __cplusplus
extern "C" {
#endif

#include "spdk/event.h"
#include "spdk/json.h"
#include "spdk/thread.h"
#include "spdk/util.h"

struct spdk_event {
	uint32_t		lcore;
	spdk_event_fn		fn;
	void			*arg1;
	void			*arg2;
};

enum spdk_reactor_state {
	SPDK_REACTOR_STATE_UNINITIALIZED = 0,
	SPDK_REACTOR_STATE_INITIALIZED = 1,
	SPDK_REACTOR_STATE_RUNNING = 2,
	SPDK_REACTOR_STATE_EXITING = 3,
	SPDK_REACTOR_STATE_SHUTDOWN = 4,
};

struct spdk_lw_thread {
	TAILQ_ENTRY(spdk_lw_thread)	link;
	bool				resched;
};

struct spdk_reactor {
	/* Lightweight threads running on this reactor */
	TAILQ_HEAD(, spdk_lw_thread)			threads;
	uint32_t					thread_count;

	/* Logical core number for this reactor. */
	uint32_t					lcore;

	struct {
		uint32_t				is_valid : 1;
		uint32_t				reserved : 31;
	} flags;

	struct spdk_ring				*events;

	/* The last known rusage values */
	struct rusage					rusage;
	uint64_t					last_rusage;
} __attribute__((aligned(SPDK_CACHE_LINE_SIZE)));

int spdk_reactors_init(void);
void spdk_reactors_fini(void);

void spdk_reactors_start(void);
void spdk_reactors_stop(void *arg1);

struct spdk_reactor *spdk_reactor_get(uint32_t lcore);

/**
 * Allocate and pass an event to each reactor, serially.
 *
 * The allocated event is processed asynchronously - i.e. spdk_for_each_reactor
 * will return prior to `fn` being called on each reactor.
 *
 * \param fn This is the function that will be called on each reactor.
 * \param arg1 Argument will be passed to fn when called.
 * \param arg2 Argument will be passed to fn when called.
 * \param cpl This will be called on the originating reactor after `fn` has been
 * called on each reactor.
 */
void spdk_for_each_reactor(spdk_event_fn fn, void *arg1, void *arg2, spdk_event_fn cpl);

struct spdk_subsystem {
	const char *name;
	/* User must call spdk_subsystem_init_next() when they are done with their initialization. */
	void (*init)(void);
	void (*fini)(void);
	void (*config)(FILE *fp);

	/**
	 * Write JSON configuration handler.
	 *
	 * \param w JSON write context
	 */
	void (*write_config_json)(struct spdk_json_write_ctx *w);
	TAILQ_ENTRY(spdk_subsystem) tailq;
};

TAILQ_HEAD(spdk_subsystem_list, spdk_subsystem);
extern struct spdk_subsystem_list g_subsystems;

struct spdk_subsystem *spdk_subsystem_find(struct spdk_subsystem_list *list, const char *name);

struct spdk_subsystem_depend {
	const char *name;
	const char *depends_on;
	TAILQ_ENTRY(spdk_subsystem_depend) tailq;
};

TAILQ_HEAD(spdk_subsystem_depend_list, spdk_subsystem_depend);
extern struct spdk_subsystem_depend_list g_subsystems_deps;

void spdk_add_subsystem(struct spdk_subsystem *subsystem);
void spdk_add_subsystem_depend(struct spdk_subsystem_depend *depend);

typedef void (*spdk_subsystem_init_fn)(int rc, void *ctx);
void spdk_subsystem_init(spdk_subsystem_init_fn cb_fn, void *cb_arg);
void spdk_subsystem_fini(spdk_msg_fn cb_fn, void *cb_arg);
void spdk_subsystem_init_next(int rc);
void spdk_subsystem_fini_next(void);
void spdk_subsystem_config(FILE *fp);
void spdk_app_json_config_load(const char *json_config_file, const char *rpc_addr,
			       spdk_subsystem_init_fn cb_fn, void *cb_arg,
			       bool stop_on_error);

/**
 * Save pointed \c subsystem configuration to the JSON write context \c w. In case of
 * error \c null is written to the JSON context.
 *
 * \param w JSON write context
 * \param subsystem the subsystem to query
 */
void spdk_subsystem_config_json(struct spdk_json_write_ctx *w, struct spdk_subsystem *subsystem);

void spdk_rpc_initialize(const char *listen_addr);
void spdk_rpc_finish(void);

/**
 * \brief Register a new subsystem
 */
#define SPDK_SUBSYSTEM_REGISTER(_name) \
	__attribute__((constructor)) static void _name ## _register(void)	\
	{									\
		spdk_add_subsystem(&_name);					\
	}

/**
 * \brief Declare that a subsystem depends on another subsystem.
 */
#define SPDK_SUBSYSTEM_DEPEND(_name, _depends_on)						\
	static struct spdk_subsystem_depend __subsystem_ ## _name ## _depend_on ## _depends_on = { \
	.name = #_name,										\
	.depends_on = #_depends_on,								\
	};											\
	__attribute__((constructor)) static void _name ## _depend_on ## _depends_on(void)	\
	{											\
		spdk_add_subsystem_depend(&__subsystem_ ## _name ## _depend_on ## _depends_on); \
	}

#ifdef __cplusplus
}
#endif

#endif /* SPDK_INTERNAL_EVENT_H */