lib/event.h

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* Thread management routine header.
   3  * Copyright (C) 1998 Kunihiro Ishiguro
   4  */
   5
   6 #ifndef _ZEBRA_THREAD_H
   7 #define _ZEBRA_THREAD_H
   8
   9 #include <zebra.h>
  10 #include <pthread.h>
  11 #include <poll.h>
  12 #include "monotime.h"
  13 #include "frratomic.h"
  14 #include "typesafe.h"
  15 #include "xref.h"
  16
  17 #ifdef __cplusplus
  18 extern "C" {
  19 #endif
  20
  21 extern bool cputime_enabled;
  22 extern unsigned long cputime_threshold;
  23 /* capturing wallclock time is always enabled since it is fast (reading
  24  * hardware TSC w/o syscalls)
  25  */
  26 extern unsigned long walltime_threshold;
  27
  28 struct rusage_t {
  29 #ifdef HAVE_CLOCK_THREAD_CPUTIME_ID
  30         struct timespec cpu;
  31 #else
  32         struct rusage cpu;
  33 #endif
  34         struct timeval real;
  35 };
  36 #define RUSAGE_T        struct rusage_t
  37
  38 #define GETRUSAGE(X) thread_getrusage(X)
  39
  40 PREDECL_LIST(thread_list);
  41 PREDECL_HEAP(thread_timer_list);
  42
  43 struct fd_handler {
  44         /* number of pfd that fit in the allocated space of pfds. This is a
  45          * constant and is the same for both pfds and copy.
  46          */
  47         nfds_t pfdsize;
  48
  49         /* file descriptors to monitor for i/o */
  50         struct pollfd *pfds;
  51         /* number of pollfds stored in pfds */
  52         nfds_t pfdcount;
  53
  54         /* chunk used for temp copy of pollfds */
  55         struct pollfd *copy;
  56         /* number of pollfds stored in copy */
  57         nfds_t copycount;
  58 };
  59
  60 struct xref_threadsched {
  61         struct xref xref;
  62
  63         const char *funcname;
  64         const char *dest;
  65         uint32_t thread_type;
  66 };
  67
  68 /* Master of the theads. */
  69 struct thread_master {
  70         char *name;
  71
  72         struct event **read;
  73         struct event **write;
  74         struct thread_timer_list_head timer;
  75         struct thread_list_head event, ready, unuse;
  76         struct list *cancel_req;
  77         bool canceled;
  78         pthread_cond_t cancel_cond;
  79         struct hash *cpu_record;
  80         int io_pipe[2];
  81         int fd_limit;
  82         struct fd_handler handler;
  83         unsigned long alloc;
  84         long selectpoll_timeout;
  85         bool spin;
  86         bool handle_signals;
  87         pthread_mutex_t mtx;
  88         pthread_t owner;
  89
  90         bool ready_run_loop;
  91         RUSAGE_T last_getrusage;
  92 };
  93
  94 /* Thread itself. */
  95 struct event {
  96         uint8_t type;             /* thread type */
  97         uint8_t add_type;         /* thread type */
  98         struct thread_list_item threaditem;
  99         struct thread_timer_list_item timeritem;
 100         struct event **ref;           /* external reference (if given) */
 101         struct thread_master *master; /* pointer to the struct thread_master */
 102         void (*func)(struct event *); /* event function */
 103         void *arg;                    /* event argument */
 104         union {
 105                 int val;              /* second argument of the event. */
 106                 int fd;               /* file descriptor in case of r/w */
 107                 struct timeval sands; /* rest of time sands value. */
 108         } u;
 109         struct timeval real;
 110         struct cpu_thread_history *hist; /* cache pointer to cpu_history */
 111         unsigned long yield;             /* yield time in microseconds */
 112         const struct xref_threadsched *xref;   /* origin location */
 113         pthread_mutex_t mtx;   /* mutex for thread.c functions */
 114         bool ignore_timer_late;
 115 };
 116
 117 #ifdef _FRR_ATTRIBUTE_PRINTFRR
 118 #pragma FRR printfrr_ext "%pTH"(struct event *)
 119 #endif
 120
 121 struct cpu_thread_history {
 122         void (*func)(struct event *);
 123         atomic_size_t total_cpu_warn;
 124         atomic_size_t total_wall_warn;
 125         atomic_size_t total_starv_warn;
 126         atomic_size_t total_calls;
 127         atomic_size_t total_active;
 128         struct time_stats {
 129                 atomic_size_t total, max;
 130         } real;
 131         struct time_stats cpu;
 132         atomic_uint_fast32_t types;
 133         const char *funcname;
 134 };
 135
 136 /* Struct timeval's tv_usec one second value.  */
 137 #define TIMER_SECOND_MICRO 1000000L
 138
 139 /* Thread types. */
 140 #define THREAD_READ           0
 141 #define THREAD_WRITE          1
 142 #define THREAD_TIMER          2
 143 #define THREAD_EVENT          3
 144 #define THREAD_READY          4
 145 #define THREAD_UNUSED         5
 146 #define THREAD_EXECUTE        6
 147
 148 /* Thread yield time.  */
 149 #define THREAD_YIELD_TIME_SLOT     10 * 1000L /* 10ms */
 150
 151 #define THREAD_TIMER_STRLEN 12
 152
 153 /* Macros. */
 154 #define THREAD_ARG(X) ((X)->arg)
 155 #define THREAD_FD(X)  ((X)->u.fd)
 156 #define THREAD_VAL(X) ((X)->u.val)
 157
 158 /*
 159  * Please consider this macro deprecated, and do not use it in new code.
 160  */
 161 #define THREAD_OFF(thread)                                                     \
 162         do {                                                                   \
 163                 if ((thread))                                                  \
 164                         event_cancel(&(thread));                               \
 165         } while (0)
 166
 167 /*
 168  * Macro wrappers to generate xrefs for all thread add calls.  Includes
 169  * file/line/function info for debugging/tracing.
 170  */
 171 #include "lib/xref.h"
 172
 173 #define _xref_t_a(addfn, type, m, f, a, v, t)                                  \
 174         ({                                                                     \
 175                 static const struct xref_threadsched _xref __attribute__(      \
 176                         (used)) = {                                            \
 177                         .xref = XREF_INIT(XREFT_THREADSCHED, NULL, __func__),  \
 178                         .funcname = #f,                                        \
 179                         .dest = #t,                                            \
 180                         .thread_type = THREAD_##type,                          \
 181                 };                                                             \
 182                 XREF_LINK(_xref.xref);                                         \
 183                 _event_add_##addfn(&_xref, m, f, a, v, t);                     \
 184         }) /* end */
 185
 186 #define event_add_read(m, f, a, v, t) _xref_t_a(read_write, READ, m, f, a, v, t)
 187 #define event_add_write(m, f, a, v, t)                                         \
 188         _xref_t_a(read_write, WRITE, m, f, a, v, t)
 189 #define event_add_timer(m, f, a, v, t) _xref_t_a(timer, TIMER, m, f, a, v, t)
 190 #define event_add_timer_msec(m, f, a, v, t)                                    \
 191         _xref_t_a(timer_msec, TIMER, m, f, a, v, t)
 192 #define event_add_timer_tv(m, f, a, v, t)                                      \
 193         _xref_t_a(timer_tv, TIMER, m, f, a, v, t)
 194 #define event_add_event(m, f, a, v, t) _xref_t_a(event, EVENT, m, f, a, v, t)
 195
 196 #define thread_execute(m,f,a,v)                                                \
 197         ({                                                                     \
 198                 static const struct xref_threadsched _xref                     \
 199                                 __attribute__((used)) = {                      \
 200                         .xref = XREF_INIT(XREFT_THREADSCHED, NULL, __func__),  \
 201                         .funcname = #f,                                        \
 202                         .dest = NULL,                                          \
 203                         .thread_type = THREAD_EXECUTE,                         \
 204                 };                                                             \
 205                 XREF_LINK(_xref.xref);                                         \
 206                 _thread_execute(&_xref, m, f, a, v);                           \
 207         }) /* end */
 208
 209 /* Prototypes. */
 210 extern struct thread_master *thread_master_create(const char *);
 211 void thread_master_set_name(struct thread_master *master, const char *name);
 212 extern void thread_master_free(struct thread_master *);
 213 extern void thread_master_free_unused(struct thread_master *);
 214
 215 extern void _event_add_read_write(const struct xref_threadsched *xref,
 216                                   struct thread_master *master,
 217                                   void (*fn)(struct event *), void *arg, int fd,
 218                                   struct event **tref);
 219
 220 extern void _event_add_timer(const struct xref_threadsched *xref,
 221                              struct thread_master *master,
 222                              void (*fn)(struct event *), void *arg, long t,
 223                              struct event **tref);
 224
 225 extern void _event_add_timer_msec(const struct xref_threadsched *xref,
 226                                   struct thread_master *master,
 227                                   void (*fn)(struct event *), void *arg, long t,
 228                                   struct event **tref);
 229
 230 extern void _event_add_timer_tv(const struct xref_threadsched *xref,
 231                                 struct thread_master *master,
 232                                 void (*fn)(struct event *), void *arg,
 233                                 struct timeval *tv, struct event **tref);
 234
 235 extern void _event_add_event(const struct xref_threadsched *xref,
 236                              struct thread_master *master,
 237                              void (*fn)(struct event *), void *arg, int val,
 238                              struct event **tref);
 239
 240 extern void _thread_execute(const struct xref_threadsched *xref,
 241                             struct thread_master *master,
 242                             void (*fn)(struct event *), void *arg, int val);
 243
 244 extern void event_cancel(struct event **event);
 245 extern void event_cancel_async(struct thread_master *, struct event **, void *);
 246 /* Cancel ready tasks with an arg matching 'arg' */
 247 extern void event_cancel_event_ready(struct thread_master *m, void *arg);
 248 /* Cancel all tasks with an arg matching 'arg', including timers and io */
 249 extern void event_cancel_event(struct thread_master *m, void *arg);
 250 extern struct event *thread_fetch(struct thread_master *, struct event *event);
 251 extern void thread_call(struct event *event);
 252 extern unsigned long thread_timer_remain_second(struct event *event);
 253 extern struct timeval thread_timer_remain(struct event *event);
 254 extern unsigned long thread_timer_remain_msec(struct event *event);
 255 extern int thread_should_yield(struct event *event);
 256 /* set yield time for thread */
 257 extern void thread_set_yield_time(struct event *event, unsigned long);
 258
 259 /* Internal libfrr exports */
 260 extern void thread_getrusage(RUSAGE_T *);
 261 extern void thread_cmd_init(void);
 262
 263 /* Returns elapsed real (wall clock) time. */
 264 extern unsigned long thread_consumed_time(RUSAGE_T *after, RUSAGE_T *before,
 265                                           unsigned long *cpu_time_elapsed);
 266
 267 /* only for use in logging functions! */
 268 extern pthread_key_t thread_current;
 269 extern char *thread_timer_to_hhmmss(char *buf, int buf_size,
 270                                     struct event *t_timer);
 271
 272 static inline bool thread_is_scheduled(struct event *thread)
 273 {
 274         if (thread)
 275                 return true;
 276
 277         return false;
 278 }
 279
 280 /* Debug signal mask */
 281 void debug_signals(const sigset_t *sigs);
 282
 283 static inline void thread_ignore_late_timer(struct event *event)
 284 {
 285         event->ignore_timer_late = true;
 286 }
 287
 288 #ifdef __cplusplus
 289 }
 290 #endif
 291
 292 #endif /* _ZEBRA_THREAD_H */