disksim_disk.h

目前最精确的磁盘模拟器的第3版

/*
 * DiskSim Storage Subsystem Simulation Environment (Version 3.0)
 * Revision Authors: John Bucy, Greg Ganger
 * Contributors: John Griffin, Jiri Schindler, Steve Schlosser
 *
 * Copyright (c) of Carnegie Mellon University, 2001, 2002, 2003.
 *
 * This software is being provided by the copyright holders under the
 * following license. By obtaining, using and/or copying this software,
 * you agree that you have read, understood, and will comply with the
 * following terms and conditions:
 *
 * Permission to reproduce, use, and prepare derivative works of this
 * software is granted provided the copyright and "No Warranty" statements
 * are included with all reproductions and derivative works and associated
 * documentation. This software may also be redistributed without charge
 * provided that the copyright and "No Warranty" statements are included
 * in all redistributions.
 *
 * NO WARRANTY. THIS SOFTWARE IS FURNISHED ON AN "AS IS" BASIS.
 * CARNEGIE MELLON UNIVERSITY MAKES NO WARRANTIES OF ANY KIND, EITHER
 * EXPRESSED OR IMPLIED AS TO THE MATTER INCLUDING, BUT NOT LIMITED
 * TO: WARRANTY OF FITNESS FOR PURPOSE OR MERCHANTABILITY, EXCLUSIVITY
 * OF RESULTS OR RESULTS OBTAINED FROM USE OF THIS SOFTWARE. CARNEGIE
 * MELLON UNIVERSITY DOES NOT MAKE ANY WARRANTY OF ANY KIND WITH RESPECT
 * TO FREEDOM FROM PATENT, TRADEMARK, OR COPYRIGHT INFRINGEMENT.
 * COPYRIGHT HOLDERS WILL BEAR NO LIABILITY FOR ANY USE OF THIS SOFTWARE
 * OR DOCUMENTATION.
 *
 */



/*
 * DiskSim Storage Subsystem Simulation Environment (Version 2.0)
 * Revision Authors: Greg Ganger
 * Contributors: Ross Cohen, John Griffin, Steve Schlosser
 *
 * Copyright (c) of Carnegie Mellon University, 1999.
 *
 * Permission to reproduce, use, and prepare derivative works of
 * this software for internal use is granted provided the copyright
 * and "No Warranty" statements are included with all reproductions
 * and derivative works. This software may also be redistributed
 * without charge provided that the copyright and "No Warranty"
 * statements are included in all redistributions.
 *
 * NO WARRANTY. THIS SOFTWARE IS FURNISHED ON AN "AS IS" BASIS.
 * CARNEGIE MELLON UNIVERSITY MAKES NO WARRANTIES OF ANY KIND, EITHER
 * EXPRESSED OR IMPLIED AS TO THE MATTER INCLUDING, BUT NOT LIMITED
 * TO: WARRANTY OF FITNESS FOR PURPOSE OR MERCHANTABILITY, EXCLUSIVITY
 * OF RESULTS OR RESULTS OBTAINED FROM USE OF THIS SOFTWARE. CARNEGIE
 * MELLON UNIVERSITY DOES NOT MAKE ANY WARRANTY OF ANY KIND WITH RESPECT
 * TO FREEDOM FROM PATENT, TRADEMARK, OR COPYRIGHT INFRINGEMENT.
 */

/*
 * DiskSim Storage Subsystem Simulation Environment
 * Authors: Greg Ganger, Bruce Worthington, Yale Patt
 *
 * Copyright (C) 1993, 1995, 1997 The Regents of the University of Michigan 
 *
 * This software is being provided by the copyright holders under the
 * following license. By obtaining, using and/or copying this software,
 * you agree that you have read, understood, and will comply with the
 * following terms and conditions:
 *
 * Permission to use, copy, modify, distribute, and sell this software
 * and its documentation for any purpose and without fee or royalty is
 * hereby granted, provided that the full text of this NOTICE appears on
 * ALL copies of the software and documentation or portions thereof,
 * including modifications, that you make.
 *
 * THIS SOFTWARE IS PROVIDED "AS IS," AND COPYRIGHT HOLDERS MAKE NO
 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED. BY WAY OF EXAMPLE,
 * BUT NOT LIMITATION, COPYRIGHT HOLDERS MAKE NO REPRESENTATIONS OR
 * WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR
 * THAT THE USE OF THE SOFTWARE OR DOCUMENTATION WILL NOT INFRINGE ANY
 * THIRD PARTY PATENTS, COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS. COPYRIGHT
 * HOLDERS WILL BEAR NO LIABILITY FOR ANY USE OF THIS SOFTWARE OR
 * DOCUMENTATION.
 *
 *  This software is provided AS IS, WITHOUT REPRESENTATION FROM THE
 * UNIVERSITY OF MICHIGAN AS TO ITS FITNESS FOR ANY PURPOSE, AND
 * WITHOUT WARRANTY BY THE UNIVERSITY OF MICHIGAN OF ANY KIND, EITHER
 * EXPRESSED OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE REGENTS
 * OF THE UNIVERSITY OF MICHIGAN SHALL NOT BE LIABLE FOR ANY DAMAGES,
 * INCLUDING SPECIAL , INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES,
 * WITH RESPECT TO ANY CLAIM ARISING OUT OF OR IN CONNECTION WITH THE
 * USE OF OR IN CONNECTION WITH THE USE OF THE SOFTWARE, EVEN IF IT HAS
 * BEEN OR IS HEREAFTER ADVISED OF THE POSSIBILITY OF SUCH DAMAGES
 *
 * The names and trademarks of copyright holders or authors may NOT be
 * used in advertising or publicity pertaining to the software without
 * specific, written prior permission. Title to copyright in this software
 * and any associated documentation will at all times remain with copyright
 * holders.
 */

#ifndef DISKSIM_DISK_H
#define DISKSIM_DISK_H

#include "disksim_stat.h"
#include "disksim_ioqueue.h"
#include "config.h"

#include <diskmodel/dm.h>

// Disk states
typedef enum {
  DISK_IDLE                = 1,
  DISK_TRANSFERING         = 2,
  DISK_WAIT_FOR_CONTROLLER = 3
} disk_state_t;

// Disk buffer states (both internal and external) 
typedef enum {
  BUFFER_EMPTY             = 1,
  BUFFER_CLEAN             = 2,
  BUFFER_DIRTY             = 3,
  BUFFER_READING           = 4,
  BUFFER_WRITING           = 5,
  BUFFER_PREEMPT           = 6,
  BUFFER_IDLE              = 7,
  BUFFER_CONTACTING        = 8,
  BUFFER_TRANSFERING       = 9
} disk_buffer_state_t;

// Disk buffer content match types 
typedef enum {
  BUFFER_COLLISION         = -1,
  BUFFER_NOMATCH	   = 0,
  BUFFER_WHOLE	           = 1,     // read 
  BUFFER_PARTIAL	   = 2,     // read 
  BUFFER_PREPEND           = 3,     // write 
  BUFFER_APPEND            = 4     // write 
} disk_cache_hit_t;

/* Extra disk buffer flag variable */
/* *** MAKE SURE THIS DOESN"T CONFLICT WITH ANY FLAGS IN global.h *** */

#define BUFFER_BACKGROUND	0x10000000

/* Disk buffer continuous read types */
typedef enum {
  BUFFER_NO_READ_AHEAD		= 0,
  BUFFER_READ_UNTIL_TRACK_END	= 1,
  BUFFER_READ_UNTIL_CYL_END	= 2,
  BUFFER_READ_UNTIL_SEG_END	= 3,
  BUFFER_DEC_PREFETCH_SCHEME    = 4
} disk_cont_read_t;

/* Disk request flags */
#define SEG_OWNED			0x00000001
#define HDA_OWNED			0x00000002
#define EXTRA_WRITE_DISCONNECT          0x00000004
#define COMPLETION_SENT                 0x00000008
#define COMPLETION_RECEIVED             0x00000010
#define FINAL_WRITE_RECONNECTION_1      0x00000020
#define FINAL_WRITE_RECONNECTION_2      0x00000040

/* Disk preseeking levels */
typedef enum {
  NO_PRESEEK                     = 0,
  PRESEEK_DURING_COMPLETION      = 1,
  PRESEEK_BEFORE_COMPLETION      = 2        /* implies 1 as well */
} disk_preseek_t;

/* Disk fastwrites levels */
typedef enum {
  NO_FASTWRITE			= 0,
  LIMITED_FASTWRITE		= 1,
  FULL_FASTWRITE	        = 2
} disk_fastwrite_t;


/* aliases */
#define ioreq_hold_disk tempptr1
#define ioreq_hold_diskreq tempptr2

/* free blocks added may change later */
#define MAXSTATS 10
#define MAXDISKS 100


typedef struct seg {
   double       time;
   disk_buffer_state_t state;
   struct seg  *next;
   struct seg  *prev;
   int          startblkno;
   int          endblkno;
   disk_buffer_state_t outstate;
   int		outbcount;
   int		minreadaheadblkno;      /* min prefetch blkno + 1 */
   int		maxreadaheadblkno;      /* max prefetch blkno + 1 */

   struct diskreq_t *diskreqlist;       /* sorted by ascendingly first blkno */
   int          size;
                                        /* diskreqlist normally starts
					 * as a single request, more
					 * can be added by read hits
					 * on the segment and write
					 * combining */

   ioreq_event *access;                 /* copy of the active ioreq
                                         * using this seg -rcohen */
   int		hold_blkno; 		/* used for prepending */
   int		hold_bcount;		/* sequential writes   */
   struct diskreq_t *recyclereq;        /* diskreq to recycle this seg */
} segment;


typedef struct diskreq_t {
   int			flags;
   ioreq_event 	       *ioreqlist;	/* sorted by ascending blkno */
   struct diskreq_t    *seg_next;	/* list attached to a segment */
   struct diskreq_t    *bus_next;
   int			outblkno;
   int			inblkno;
   segment	       *seg;		/* associated cache segment */
   int          	watermark;
   disk_cache_hit_t     hittype;	/* for cache use */
   double		overhead_done;
   char			space[20];
} diskreq;


typedef struct {
   double  seektime;
   double  latency;
   double  xfertime;
   int     seekdistance;
   int     zeroseeks;
   int     zerolatency;
   int     highblkno;
   statgen seekdiststats;
   statgen seektimestats;
   statgen rotlatstats;
   statgen xfertimestats;
   statgen postimestats;
   statgen acctimestats;
   int     writecombs;
   int     readmisses;
   int     writemisses;
   int     fullreadhits;
   int     appendhits;
   int     prependhits;
   int     readinghits;
   double  runreadingsize;
   double  remreadingsize;
   int     parthits;
   double  runpartsize;
   double  rempartsize;
   int     interfere[2];
   double  requestedbus;
   double  waitingforbus;
   int     numbuswaits;
} diskstat;


// replaces currangle/currtime/... foo
struct disk_currstate {
  struct dm_mech_state s;
  dm_time_t t;
};

typedef struct disk {
  struct device_header hdr;
  struct dm_disk_if    *model;
  struct dm_mech_state mech_state;

  int	               devno;

  // if true, uses constant access-time model,
  // bypasses some of mech model
  int       const_acctime; 
  // constant access time; only meaningful if const_acctime is true
  double          acctime;

  // if true, uses constant seek-time model,
  // bypasses some of mech model
  int       const_seektime;
  // constant seek time; only meaningful if const_seektime set
  double          seektime;

  // "Per-request overhead time"
  double       overhead;
  double       timescale;
  
  // which syncset we're in; only really used to sync up disks in
  // syncsets once at beginning of simulation
  int          syncset;

  // list of io's not completed 
  struct ioq  *queue;	       
  // "Avg" value used in suboptimal schedulers 
  int	       sectpercyl;    

  // controller stuff
  int		hold_bus_for_whole_read_xfer;
  int		hold_bus_for_whole_write_xfer;

  // cache stuff
  int		almostreadhits;
  int		sneakyfullreadhits;
  int		sneakypartialreadhits;
  int		sneakyintermediatereadhits;
  int		readhitsonwritedata;
  int		writeprebuffering;

  // diskctlr
  int		preseeking;
  // ctlr/cache
  int		neverdisconnect;

  // doesn't appear to be used
  // int           qlen;
  int           maxqlen;

  int           busy;

  // cache/controller 
  int		prev_readahead_min;
  int		write_hit_stop_readahead;
  int		read_direct_to_buffer;
  int		immedtrans_any_readhit;
  int		readanyfreeblocks;

  int		numsegs;
  int		numwritesegs;
  segment *	dedicatedwriteseg;
  int		segsize;
  double	writewater;
  double	readwater;