lib/thread.h

   1 /* Thread management routine header.
   2  * Copyright (C) 1998 Kunihiro Ishiguro
   3  *
   4  * This file is part of GNU Zebra.
   5  *
   6  * GNU Zebra is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2, or (at your option) any
   9  * later version.
  10  *
  11  * GNU Zebra is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with GNU Zebra; see the file COPYING.  If not, write to the Free
  18  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  19  * 02111-1307, USA.
  20  */
  21
  22 #ifndef _ZEBRA_THREAD_H
  23 #define _ZEBRA_THREAD_H
  24
  25 struct rusage_t
  26 {
  27 #ifdef HAVE_RUSAGE
  28   struct rusage cpu;
  29 #endif
  30   struct timeval real;
  31 };
  32 #define RUSAGE_T        struct rusage_t
  33
  34 #ifdef HAVE_RUSAGE
  35 #define GETRUSAGE(X)    \
  36   getrusage(RUSAGE_SELF, &((X)->cpu));  \
  37   gettimeofday(&recent_time, NULL); (X)->real = recent_time
  38 #else
  39 #define GETRUSAGE(X)    \
  40   gettimeofday(&recent_time, NULL); (X)->real = recent_time
  41 #endif /* HAVE_RUSAGE */
  42
  43 /* Linked list of thread. */
  44 struct thread_list
  45 {
  46   struct thread *head;
  47   struct thread *tail;
  48   int count;
  49 };
  50
  51 /* Master of the theads. */
  52 struct thread_master
  53 {
  54   struct thread_list read;
  55   struct thread_list write;
  56   struct thread_list timer;
  57   struct thread_list event;
  58   struct thread_list ready;
  59   struct thread_list unuse;
  60   struct thread_list background;
  61   fd_set readfd;
  62   fd_set writefd;
  63   fd_set exceptfd;
  64   unsigned long alloc;
  65 };
  66
  67 /* Thread itself. */
  68 struct thread
  69 {
  70   unsigned char type;           /* thread type */
  71   unsigned char add_type;       /* thread type */
  72   struct thread *next;          /* next pointer of the thread */
  73   struct thread *prev;          /* previous pointer of the thread */
  74   struct thread_master *master; /* pointer to the struct thread_master. */
  75   int (*func) (struct thread *); /* event function */
  76   void *arg;                    /* event argument */
  77   union {
  78     int val;                    /* second argument of the event. */
  79     int fd;                     /* file descriptor in case of read/write. */
  80     struct timeval sands;       /* rest of time sands value. */
  81   } u;
  82   RUSAGE_T ru;                  /* Indepth usage info.  */
  83   struct cpu_thread_history *hist; /* cache pointer to cpu_history */
  84   char* funcname;
  85 };
  86
  87 struct cpu_thread_history
  88 {
  89   int (*func)(struct thread *);
  90   const char *funcname;
  91   unsigned int total_calls;
  92   struct time_stats
  93   {
  94     unsigned long total, max;
  95   } real;
  96 #ifdef HAVE_RUSAGE
  97   struct time_stats cpu;
  98 #endif
  99   unsigned char types;
 100 };
 101
 102 /* Thread types. */
 103 #define THREAD_READ           0
 104 #define THREAD_WRITE          1
 105 #define THREAD_TIMER          2
 106 #define THREAD_EVENT          3
 107 #define THREAD_READY          4
 108 #define THREAD_BACKGROUND     5
 109 #define THREAD_UNUSED         6
 110 #define THREAD_EXECUTE        7
 111
 112 /* Thread yield time.  */
 113 #define THREAD_YIELD_TIME_SLOT     10 * 1000L /* 10ms */
 114
 115 /* Macros. */
 116 #define THREAD_ARG(X) ((X)->arg)
 117 #define THREAD_FD(X)  ((X)->u.fd)
 118 #define THREAD_VAL(X) ((X)->u.val)
 119
 120 #define THREAD_READ_ON(master,thread,func,arg,sock) \
 121   do { \
 122     if (! thread) \
 123       thread = thread_add_read (master, func, arg, sock); \
 124   } while (0)
 125
 126 #define THREAD_WRITE_ON(master,thread,func,arg,sock) \
 127   do { \
 128     if (! thread) \
 129       thread = thread_add_write (master, func, arg, sock); \
 130   } while (0)
 131
 132 #define THREAD_TIMER_ON(master,thread,func,arg,time) \
 133   do { \
 134     if (! thread) \
 135       thread = thread_add_timer (master, func, arg, time); \
 136   } while (0)
 137
 138 #define THREAD_OFF(thread) \
 139   do { \
 140     if (thread) \
 141       { \
 142         thread_cancel (thread); \
 143         thread = NULL; \
 144       } \
 145   } while (0)
 146
 147 #define THREAD_READ_OFF(thread)  THREAD_OFF(thread)
 148 #define THREAD_WRITE_OFF(thread)  THREAD_OFF(thread)
 149 #define THREAD_TIMER_OFF(thread)  THREAD_OFF(thread)
 150
 151 #define thread_add_read(m,f,a,v) funcname_thread_add_read(m,f,a,v,#f)
 152 #define thread_add_write(m,f,a,v) funcname_thread_add_write(m,f,a,v,#f)
 153 #define thread_add_timer(m,f,a,v) funcname_thread_add_timer(m,f,a,v,#f)
 154 #define thread_add_timer_msec(m,f,a,v) funcname_thread_add_timer_msec(m,f,a,v,#f)
 155 #define thread_add_event(m,f,a,v) funcname_thread_add_event(m,f,a,v,#f)
 156 #define thread_execute(m,f,a,v) funcname_thread_execute(m,f,a,v,#f)
 157
 158 /* The 4th arg to thread_add_background is the # of milliseconds to delay. */
 159 #define thread_add_background(m,f,a,v) funcname_thread_add_background(m,f,a,v,#f)
 160
 161 /* Prototypes. */
 162 extern struct thread_master *thread_master_create (void);
 163 extern void thread_master_free (struct thread_master *);
 164
 165 extern struct thread *funcname_thread_add_read (struct thread_master *,
 166                                                 int (*)(struct thread *),
 167                                                 void *, int, const char*);
 168 extern struct thread *funcname_thread_add_write (struct thread_master *,
 169                                                  int (*)(struct thread *),
 170                                                  void *, int, const char*);
 171 extern struct thread *funcname_thread_add_timer (struct thread_master *,
 172                                                  int (*)(struct thread *),
 173                                                  void *, long, const char*);
 174 extern struct thread *funcname_thread_add_timer_msec (struct thread_master *,
 175                                                       int (*)(struct thread *),
 176                                                       void *, long, const char*);
 177 extern struct thread *funcname_thread_add_event (struct thread_master *,
 178                                                  int (*)(struct thread *),
 179                                                  void *, int, const char*);
 180 extern struct thread *funcname_thread_add_background (struct thread_master *,
 181                                                int (*func)(struct thread *),
 182                                                void *arg,
 183                                                long milliseconds_to_delay,
 184                                                const char *funcname);
 185 extern struct thread *funcname_thread_execute (struct thread_master *,
 186                                                int (*)(struct thread *),
 187                                                void *, int, const char *);
 188 extern void thread_cancel (struct thread *);
 189 extern unsigned int thread_cancel_event (struct thread_master *, void *);
 190 extern struct thread *thread_fetch (struct thread_master *, struct thread *);
 191 extern void thread_call (struct thread *);
 192 extern unsigned long thread_timer_remain_second (struct thread *);
 193 extern int thread_should_yield (struct thread *);
 194
 195 extern struct cmd_element show_thread_cpu_cmd;
 196
 197 /* Returns elapsed real (wall clock) time. */
 198 extern unsigned long thread_consumed_time(RUSAGE_T *after, RUSAGE_T *before,
 199                                           unsigned long *cpu_time_elapsed);
 200
 201 /* Global variable containing a recent result from gettimeofday.  This can
 202    be used instead of calling gettimeofday if a recent value is sufficient.
 203    This is guaranteed to be refreshed before a thread is called. */
 204 extern struct timeval recent_time;
 205
 206 #endif /* _ZEBRA_THREAD_H */