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 along
  17  * with this program; see the file COPYING; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #ifndef _ZEBRA_THREAD_H
  22 #define _ZEBRA_THREAD_H
  23
  24 #include <zebra.h>
  25 #include <pthread.h>
  26 #include <poll.h>
  27 #include "monotime.h"
  28
  29 struct rusage_t
  30 {
  31   struct rusage cpu;
  32   struct timeval real;
  33 };
  34 #define RUSAGE_T        struct rusage_t
  35
  36 #define GETRUSAGE(X) thread_getrusage(X)
  37
  38 /* Linked list of thread. */
  39 struct thread_list
  40 {
  41   struct thread *head;
  42   struct thread *tail;
  43   int count;
  44 };
  45
  46 struct pqueue;
  47
  48 struct fd_handler
  49 {
  50   /* number of pfd stored in pfds */
  51   nfds_t pfdcount;
  52   /* number of pfd stored in pfds + number of snmp pfd */
  53   nfds_t pfdcountsnmp;
  54   /* number of pfd that fit in the allocated space of pfds */
  55   nfds_t pfdsize;
  56   /* file descriptors to monitor for i/o */
  57   struct pollfd *pfds;
  58   /* chunk used for temp copy of pollfds */
  59   struct pollfd *copy;
  60 };
  61
  62 /* Master of the theads. */
  63 struct thread_master
  64 {
  65   struct thread **read;
  66   struct thread **write;
  67   struct pqueue *timer;
  68   struct thread_list event;
  69   struct thread_list ready;
  70   struct thread_list unuse;
  71   int io_pipe[2];
  72   int fd_limit;
  73   struct fd_handler handler;
  74   unsigned long alloc;
  75   long selectpoll_timeout;
  76   bool spin;
  77   bool handle_signals;
  78   pthread_mutex_t mtx;
  79   pthread_t owner;
  80 };
  81
  82 typedef unsigned char thread_type;
  83
  84 /* Thread itself. */
  85 struct thread
  86 {
  87   thread_type type;                 /* thread type */
  88   thread_type add_type;             /* thread type */
  89   struct thread *next;              /* next pointer of the thread */
  90   struct thread *prev;              /* previous pointer of the thread */
  91   struct thread **ref;              /* external reference (if given) */
  92   struct thread_master *master;     /* pointer to the struct thread_master */
  93   int (*func) (struct thread *);    /* event function */
  94   void *arg;                        /* event argument */
  95   union {
  96     int val;                        /* second argument of the event. */
  97     int fd;                         /* file descriptor in case of r/w */
  98     struct timeval sands;           /* rest of time sands value. */
  99   } u;
 100   int index;                        /* queue position for timers */
 101   struct timeval real;
 102   struct cpu_thread_history *hist;  /* cache pointer to cpu_history */
 103   unsigned long yield;              /* yield time in microseconds */
 104   const char *funcname;             /* name of thread function */
 105   const char *schedfrom;            /* source file thread was scheduled from */
 106   int schedfrom_line;               /* line number of source file */
 107   pthread_mutex_t mtx;              /* mutex for thread.c functions */
 108 };
 109
 110 struct cpu_thread_history
 111 {
 112   int (*func)(struct thread *);
 113   unsigned int total_calls;
 114   unsigned int total_active;
 115   struct time_stats
 116   {
 117     unsigned long total, max;
 118   } real;
 119   struct time_stats cpu;
 120   thread_type types;
 121   const char *funcname;
 122 };
 123
 124 /* Struct timeval's tv_usec one second value.  */
 125 #define TIMER_SECOND_MICRO 1000000L
 126
 127 /* Thread types. */
 128 #define THREAD_READ           0
 129 #define THREAD_WRITE          1
 130 #define THREAD_TIMER          2
 131 #define THREAD_EVENT          3
 132 #define THREAD_READY          4
 133 #define THREAD_UNUSED         5
 134 #define THREAD_EXECUTE        6
 135
 136 /* Thread yield time.  */
 137 #define THREAD_YIELD_TIME_SLOT     10 * 1000L /* 10ms */
 138
 139 /* Macros. */
 140 #define THREAD_ARG(X) ((X)->arg)
 141 #define THREAD_FD(X)  ((X)->u.fd)
 142 #define THREAD_VAL(X) ((X)->u.val)
 143
 144 #define THREAD_OFF(thread) \
 145   do { \
 146     if (thread) \
 147       { \
 148         thread_cancel (thread); \
 149         thread = NULL; \
 150       } \
 151   } while (0)
 152
 153 #define THREAD_READ_OFF(thread)  THREAD_OFF(thread)
 154 #define THREAD_WRITE_OFF(thread)  THREAD_OFF(thread)
 155 #define THREAD_TIMER_OFF(thread)  THREAD_OFF(thread)
 156
 157 #define debugargdef  const char *funcname, const char *schedfrom, int fromln
 158
 159 #define thread_add_read(m,f,a,v,t) funcname_thread_add_read_write(THREAD_READ,m,f,a,v,t,#f,__FILE__,__LINE__)
 160 #define thread_add_write(m,f,a,v,t) funcname_thread_add_read_write(THREAD_WRITE,m,f,a,v,t,#f,__FILE__,__LINE__)
 161 #define thread_add_timer(m,f,a,v,t) funcname_thread_add_timer(m,f,a,v,t,#f,__FILE__,__LINE__)
 162 #define thread_add_timer_msec(m,f,a,v,t) funcname_thread_add_timer_msec(m,f,a,v,t,#f,__FILE__,__LINE__)
 163 #define thread_add_timer_tv(m,f,a,v,t) funcname_thread_add_timer_tv(m,f,a,v,t,#f,__FILE__,__LINE__)
 164 #define thread_add_event(m,f,a,v,t) funcname_thread_add_event(m,f,a,v,t,#f,__FILE__,__LINE__)
 165 #define thread_execute(m,f,a,v) funcname_thread_execute(m,f,a,v,#f,__FILE__,__LINE__)
 166
 167 /* Prototypes. */
 168 extern struct thread_master *thread_master_create (void);
 169 extern void thread_master_free (struct thread_master *);
 170 extern void thread_master_free_unused(struct thread_master *);
 171
 172 extern struct thread * funcname_thread_add_read_write (int dir, struct thread_master *,
 173     int (*)(struct thread *), void *, int, struct thread **, debugargdef);
 174
 175 extern struct thread * funcname_thread_add_timer (struct thread_master *,
 176     int (*)(struct thread *), void *, long, struct thread **, debugargdef);
 177
 178 extern struct thread * funcname_thread_add_timer_msec (struct thread_master *,
 179     int (*)(struct thread *), void *, long, struct thread **, debugargdef);
 180
 181 extern struct thread * funcname_thread_add_timer_tv (struct thread_master *,
 182     int (*)(struct thread *), void *, struct timeval *, struct thread **, debugargdef);
 183
 184 extern struct thread * funcname_thread_add_event (struct thread_master *,
 185     int (*)(struct thread *), void *, int, struct thread **, debugargdef);
 186
 187 extern void funcname_thread_execute (struct thread_master *,
 188     int (*)(struct thread *), void *, int, debugargdef);
 189 #undef debugargdef
 190
 191 extern void thread_cancel (struct thread *);
 192 extern unsigned int thread_cancel_event (struct thread_master *, void *);
 193 extern struct thread *thread_fetch (struct thread_master *, struct thread *);
 194 extern void thread_call (struct thread *);
 195 extern unsigned long thread_timer_remain_second (struct thread *);
 196 extern struct timeval thread_timer_remain(struct thread*);
 197 extern int thread_should_yield (struct thread *);
 198 /* set yield time for thread */
 199 extern void thread_set_yield_time (struct thread *, unsigned long);
 200
 201 /* Internal libfrr exports */
 202 extern void thread_getrusage (RUSAGE_T *);
 203 extern void thread_cmd_init (void);
 204
 205 /* Returns elapsed real (wall clock) time. */
 206 extern unsigned long thread_consumed_time(RUSAGE_T *after, RUSAGE_T *before,
 207                                           unsigned long *cpu_time_elapsed);
 208
 209 /* only for use in logging functions! */
 210 extern struct thread *thread_current;
 211
 212 #endif /* _ZEBRA_THREAD_H */