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 #include "frratomic.h"
  29 #include "typesafe.h"
  30 #include "xref.h"
  31
  32 #ifdef __cplusplus
  33 extern "C" {
  34 #endif
  35
  36 struct rusage_t {
  37         struct rusage cpu;
  38         struct timeval real;
  39 };
  40 #define RUSAGE_T        struct rusage_t
  41
  42 #define GETRUSAGE(X) thread_getrusage(X)
  43
  44 PREDECL_LIST(thread_list);
  45 PREDECL_HEAP(thread_timer_list);
  46
  47 struct fd_handler {
  48         /* number of pfd that fit in the allocated space of pfds. This is a
  49          * constant and is the same for both pfds and copy.
  50          */
  51         nfds_t pfdsize;
  52
  53         /* file descriptors to monitor for i/o */
  54         struct pollfd *pfds;
  55         /* number of pollfds stored in pfds */
  56         nfds_t pfdcount;
  57
  58         /* chunk used for temp copy of pollfds */
  59         struct pollfd *copy;
  60         /* number of pollfds stored in copy */
  61         nfds_t copycount;
  62 };
  63
  64 struct xref_threadsched {
  65         struct xref xref;
  66
  67         const char *funcname;
  68         const char *dest;
  69         uint32_t thread_type;
  70 };
  71
  72 /* Master of the theads. */
  73 struct thread_master {
  74         char *name;
  75
  76         struct thread **read;
  77         struct thread **write;
  78         struct thread_timer_list_head timer;
  79         struct thread_list_head event, ready, unuse;
  80         struct list *cancel_req;
  81         bool canceled;
  82         pthread_cond_t cancel_cond;
  83         struct hash *cpu_record;
  84         int io_pipe[2];
  85         int fd_limit;
  86         struct fd_handler handler;
  87         unsigned long alloc;
  88         long selectpoll_timeout;
  89         bool spin;
  90         bool handle_signals;
  91         pthread_mutex_t mtx;
  92         pthread_t owner;
  93
  94         bool ready_run_loop;
  95         RUSAGE_T last_getrusage;
  96 };
  97
  98 /* Thread itself. */
  99 struct thread {
 100         uint8_t type;             /* thread type */
 101         uint8_t add_type;         /* thread type */
 102         struct thread_list_item threaditem;
 103         struct thread_timer_list_item timeritem;
 104         struct thread **ref;      /* external reference (if given) */
 105         struct thread_master *master; /* pointer to the struct thread_master */
 106         int (*func)(struct thread *); /* event function */
 107         void *arg;                    /* event argument */
 108         union {
 109                 int val;              /* second argument of the event. */
 110                 int fd;               /* file descriptor in case of r/w */
 111                 struct timeval sands; /* rest of time sands value. */
 112         } u;
 113         struct timeval real;
 114         struct cpu_thread_history *hist; /* cache pointer to cpu_history */
 115         unsigned long yield;             /* yield time in microseconds */
 116         const struct xref_threadsched *xref;   /* origin location */
 117         pthread_mutex_t mtx;   /* mutex for thread.c functions */
 118 };
 119
 120 struct cpu_thread_history {
 121         int (*func)(struct thread *);
 122         atomic_size_t total_calls;
 123         atomic_size_t total_active;
 124         struct time_stats {
 125                 atomic_size_t total, max;
 126         } real;
 127         struct time_stats cpu;
 128         atomic_uint_fast32_t types;
 129         const char *funcname;
 130 };
 131
 132 /* Struct timeval's tv_usec one second value.  */
 133 #define TIMER_SECOND_MICRO 1000000L
 134
 135 /* Thread types. */
 136 #define THREAD_READ           0
 137 #define THREAD_WRITE          1
 138 #define THREAD_TIMER          2
 139 #define THREAD_EVENT          3
 140 #define THREAD_READY          4
 141 #define THREAD_UNUSED         5
 142 #define THREAD_EXECUTE        6
 143
 144 /* Thread yield time.  */
 145 #define THREAD_YIELD_TIME_SLOT     10 * 1000L /* 10ms */
 146
 147 #define THREAD_TIMER_STRLEN 12
 148
 149 /* Macros. */
 150 #define THREAD_ARG(X) ((X)->arg)
 151 #define THREAD_FD(X)  ((X)->u.fd)
 152 #define THREAD_VAL(X) ((X)->u.val)
 153
 154 /*
 155  * Please consider this macro deprecated, and do not use it in new code.
 156  */
 157 #define THREAD_OFF(thread)                                             \
 158         do {                                                           \
 159                 if ((thread))                                          \
 160                         thread_cancel(&(thread));                      \
 161         } while (0)
 162
 163 /*
 164  * Macro wrappers to generate xrefs for all thread add calls.  Includes
 165  * file/line/function info for debugging/tracing.
 166  */
 167 #include "lib/xref.h"
 168
 169 #define _xref_t_a(addfn, type, m, f, a, v, t)                                  \
 170         ({                                                                     \
 171                 static const struct xref_threadsched _xref                     \
 172                                 __attribute__((used)) = {                      \
 173                         .xref = XREF_INIT(XREFT_THREADSCHED, NULL, __func__),  \
 174                         .funcname = #f,                                        \
 175                         .dest = #t,                                            \
 176                         .thread_type = THREAD_ ## type,                        \
 177                 };                                                             \
 178                 XREF_LINK(_xref.xref);                                         \
 179                 _thread_add_ ## addfn(&_xref, m, f, a, v, t);                  \
 180         })                                                                     \
 181         /* end */
 182
 183 #define thread_add_read(m,f,a,v,t)       _xref_t_a(read_write, READ,  m,f,a,v,t)
 184 #define thread_add_write(m,f,a,v,t)      _xref_t_a(read_write, WRITE, m,f,a,v,t)
 185 #define thread_add_timer(m,f,a,v,t)      _xref_t_a(timer,      TIMER, m,f,a,v,t)
 186 #define thread_add_timer_msec(m,f,a,v,t) _xref_t_a(timer_msec, TIMER, m,f,a,v,t)
 187 #define thread_add_timer_tv(m,f,a,v,t)   _xref_t_a(timer_tv,   TIMER, m,f,a,v,t)
 188 #define thread_add_event(m,f,a,v,t)      _xref_t_a(event,      EVENT, m,f,a,v,t)
 189
 190 #define thread_execute(m,f,a,v)                                                \
 191         ({                                                                     \
 192                 static const struct xref_threadsched _xref                     \
 193                                 __attribute__((used)) = {                      \
 194                         .xref = XREF_INIT(XREFT_THREADSCHED, NULL, __func__),  \
 195                         .funcname = #f,                                        \
 196                         .dest = NULL,                                          \
 197                         .thread_type = THREAD_EXECUTE,                         \
 198                 };                                                             \
 199                 XREF_LINK(_xref.xref);                                         \
 200                 _thread_execute(&_xref, m, f, a, v);                           \
 201         }) /* end */
 202
 203 /* Prototypes. */
 204 extern struct thread_master *thread_master_create(const char *);
 205 void thread_master_set_name(struct thread_master *master, const char *name);
 206 extern void thread_master_free(struct thread_master *);
 207 extern void thread_master_free_unused(struct thread_master *);
 208
 209 extern struct thread *_thread_add_read_write(
 210         const struct xref_threadsched *xref, struct thread_master *master,
 211         int (*fn)(struct thread *), void *arg, int fd, struct thread **tref);
 212
 213 extern struct thread *_thread_add_timer(
 214         const struct xref_threadsched *xref, struct thread_master *master,
 215         int (*fn)(struct thread *), void *arg, long t, struct thread **tref);
 216
 217 extern struct thread *_thread_add_timer_msec(
 218         const struct xref_threadsched *xref, struct thread_master *master,
 219         int (*fn)(struct thread *), void *arg, long t, struct thread **tref);
 220
 221 extern struct thread *_thread_add_timer_tv(
 222         const struct xref_threadsched *xref, struct thread_master *master,
 223         int (*fn)(struct thread *), void *arg, struct timeval *tv,
 224         struct thread **tref);
 225
 226 extern struct thread *_thread_add_event(
 227         const struct xref_threadsched *xref, struct thread_master *master,
 228         int (*fn)(struct thread *), void *arg, int val, struct thread **tref);
 229
 230 extern void _thread_execute(const struct xref_threadsched *xref,
 231                             struct thread_master *master,
 232                             int (*fn)(struct thread *), void *arg, int val);
 233
 234 extern void thread_cancel(struct thread **event);
 235 extern void thread_cancel_async(struct thread_master *, struct thread **,
 236                                 void *);
 237 /* Cancel ready tasks with an arg matching 'arg' */
 238 extern void thread_cancel_event_ready(struct thread_master *m, void *arg);
 239 /* Cancel all tasks with an arg matching 'arg', including timers and io */
 240 extern void thread_cancel_event(struct thread_master *m, void *arg);
 241 extern struct thread *thread_fetch(struct thread_master *, struct thread *);
 242 extern void thread_call(struct thread *);
 243 extern unsigned long thread_timer_remain_second(struct thread *);
 244 extern struct timeval thread_timer_remain(struct thread *);
 245 extern unsigned long thread_timer_remain_msec(struct thread *);
 246 extern int thread_should_yield(struct thread *);
 247 /* set yield time for thread */
 248 extern void thread_set_yield_time(struct thread *, unsigned long);
 249
 250 /* Internal libfrr exports */
 251 extern void thread_getrusage(RUSAGE_T *);
 252 extern void thread_cmd_init(void);
 253
 254 /* Returns elapsed real (wall clock) time. */
 255 extern unsigned long thread_consumed_time(RUSAGE_T *after, RUSAGE_T *before,
 256                                           unsigned long *cpu_time_elapsed);
 257
 258 /* only for use in logging functions! */
 259 extern pthread_key_t thread_current;
 260 extern char *thread_timer_to_hhmmss(char *buf, int buf_size,
 261                 struct thread *t_timer);
 262
 263 /* Debug signal mask */
 264 void debug_signals(const sigset_t *sigs);
 265
 266 #ifdef __cplusplus
 267 }
 268 #endif
 269
 270 #endif /* _ZEBRA_THREAD_H */