/*
   Copyright (c) 2006-2009 Gluster, Inc. <http://www.gluster.com>
   This file is part of GlusterFS.

   GlusterFS is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published
   by the Free Software Foundation; either version 3 of the License,
   or (at your option) any later version.

   GlusterFS is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see
   <http://www.gnu.org/licenses/>.
*/

#ifndef _ALU_H
#define _ALU_H

#ifndef _CONFIG_H
#define _CONFIG_H
#include "config.h"
#endif

#include "scheduler.h"

struct alu_sched;

struct alu_sched_struct {
  xlator_t *xl;
  struct xlator_stats stats;
  unsigned char eligible;
};

// Write better name for these functions
struct alu_limits {
  struct alu_limits *next;
  int64_t (*max_value) (struct xlator_stats *); /* Max limit, specified by the user */
  int64_t (*min_value) (struct xlator_stats *); /* Min limit, specified by the user */
  int64_t (*cur_value) (struct xlator_stats *); /* Current values of variables got from stats call */
};

struct alu_threshold {
  struct alu_threshold *next;
  int64_t (*diff_value) (struct xlator_stats *max, struct xlator_stats *min); /* Diff b/w max and min */
  int64_t (*entry_value) (struct xlator_stats *); /* Limit specified user */
  int64_t (*exit_value) (struct xlator_stats *); /* Exit point for the limit */
  int64_t (*sched_value) (struct xlator_stats *); /* This will return the index of the child area */
};

struct alu_sched_node {
  struct alu_sched_node *next;
  int32_t index;
};

struct alu_sched {
  struct alu_limits *limits_fn;
  struct alu_threshold *threshold_fn;
  struct alu_sched_struct *array;
  struct alu_sched_node *sched_node;
  struct alu_threshold *sched_method;
  struct xlator_stats max_limit;
  struct xlator_stats min_limit;
  struct xlator_stats entry_limit;
  struct xlator_stats exit_limit;
  struct xlator_stats spec_limit;     /* User given limit */

  pthread_mutex_t alu_mutex;
  struct timeval last_stat_fetch;
  uint32_t refresh_interval;      /* in seconds */
  uint32_t refresh_create_count;  /* num-file-create */

  int32_t sched_nodes_pending;

  int32_t sched_index;  /* used for round robin scheduling in case of many nodes getting the criteria match. */
  int32_t child_count;

};

struct _alu_local_t {
  int32_t call_count;
};

typedef struct _alu_local_t alu_local_t;

#endif /* _ALU_H */