/* Thread management routine
* Copyright (C) 1998, 2000 Kunihiro Ishiguro <kunihiro@zebra.org>
*
* This file is part of GNU Zebra.
*
* GNU Zebra is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2, or (at your option) any
* later version.
*
* GNU Zebra is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU Zebra; see the file COPYING. If not, write to the Free
* Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
* 02111-1307, USA.
*/
/* #define DEBUG */
#include <zebra.h>
#include "thread.h"
#include "memory.h"
#include "log.h"
#include "hash.h"
#include "command.h"
#include "sigevent.h"
static struct hash *cpu_record = NULL;
/* Struct timeval's tv_usec one second value. */
#define TIMER_SECOND_MICRO 1000000L
struct timeval
timeval_adjust (struct timeval a)
{
while (a.tv_usec >= TIMER_SECOND_MICRO)
{
a.tv_usec -= TIMER_SECOND_MICRO;
a.tv_sec++;
}
while (a.tv_usec < 0)
{
a.tv_usec += TIMER_SECOND_MICRO;
a.tv_sec--;
}
if (a.tv_sec < 0)
{
a.tv_sec = 0;
a.tv_usec = 10;
}
if (a.tv_sec > TIMER_SECOND_MICRO)
a.tv_sec = TIMER_SECOND_MICRO;
return a;
}
static struct timeval
timeval_subtract (struct timeval a, struct timeval b)
{
struct timeval ret;
ret.tv_usec = a.tv_usec - b.tv_usec;
ret.tv_sec = a.tv_sec - b.tv_sec;
return timeval_adjust (ret);
}
static int
timeval_cmp (struct timeval a, struct timeval b)
{
return (a.tv_sec == b.tv_sec
? a.tv_usec - b.tv_usec : a.tv_sec - b.tv_sec);
}
static unsigned long
timeval_elapsed (struct timeval a, struct timeval b)
{
return (((a.tv_sec - b.tv_sec) * TIMER_SECOND_MICRO)
+ (a.tv_usec - b.tv_usec));
}
static unsigned int
cpu_record_hash_key (struct cpu_thread_history *a)
{
return (unsigned int) a->func;
}
static int
cpu_record_hash_cmp (struct cpu_thread_history *a,
struct cpu_thread_history *b)
{
return a->func == b->func;
}
static void*
cpu_record_hash_alloc (struct cpu_thread_history *a)
{
struct cpu_thread_history *new;
new = XMALLOC( MTYPE_TMP/*XXX*/, sizeof *new);
memset(new, 0, sizeof *new);
new->func = a->func;
new->funcname = XSTRDUP(MTYPE_TMP/*XXX*/,a->funcname);
return new;
}
static inline void
vty_out_cpu_thread_history(struct vty* vty,
struct cpu_thread_history *a)
{
vty_out(vty, " %7ld.%03ld %9d %8ld %10ld %c%c%c%c%c %s%s",
a->total/1000, a->total%1000, a->total_calls,
a->total/a->total_calls, a->max,
a->types & (1 << THREAD_READ) ? 'R':' ',
a->types & (1 << THREAD_WRITE) ? 'W':' ',
a->types & (1 << THREAD_TIMER) ? 'T':' ',
a->types & (1 << THREAD_EVENT) ? 'E':' ',
a->types & (1 << THREAD_EXECUTE) ? 'X':' ',
a->funcname, VTY_NEWLINE);
}
static void
cpu_record_hash_print(struct hash_backet *bucket,
void *args[])
{
struct cpu_thread_history *totals = args[0];
struct vty *vty = args[1];
unsigned char *filter = args[2];
struct cpu_thread_history *a = bucket->data;
a = bucket->data;
if ( !(a->types & *filter) )
return;
vty_out_cpu_thread_history(vty,a);
totals->total += a->total;
totals->total_calls += a->total_calls;
if (totals->max < a->max)
totals->max = a->max;
}
static void
cpu_record_print(struct vty *vty, unsigned char filter)
{
struct cpu_thread_history tmp;
void *args[3] = {&tmp, vty, &filter};
memset(&tmp, 0, sizeof tmp);
tmp.funcname = "TOTAL";
tmp.types = filter;
vty_out(vty,
" Runtime(ms) Invoked Avg uSecs Max uSecs Type Thread%s",
VTY_NEWLINE);
hash_iterate(cpu_record,
(void(*)(struct hash_backet*,void*))cpu_record_hash_print,
args);
if (tmp.total_calls > 0)
vty_out_cpu_thread_history(vty, &tmp);
}
DEFUN(show_thread_cpu,
show_thread_cpu_cmd,
"show thread cpu [FILTER]",
SHOW_STR
"Thread information\n"
"Thread CPU usage\n"
"Display filter (rwtex)\n")
{
int i = 0;
unsigned char filter = 0xff;
if (argc > 0)
{
filter = 0;
while (argv[0][i] != '\0')
{
switch ( argv[0][i] )
{
case 'r':
case 'R':
filter |= (1 << THREAD_READ);
break;
case 'w':
case 'W':
filter |= (1 << THREAD_WRITE);
break;
case 't':
case 'T':
filter |= (1 << THREAD_TIMER);
break;
case 'e':
case 'E':
filter |= (1 << THREAD_EVENT);
break;
case 'x':
case 'X':
filter |= (1 << THREAD_EXECUTE);
break;
default:
break;
}
++i;
}
if (filter == 0)
{
vty_out(vty, "Invalid filter \"%s\" specified, must contain at least one of 'RWTEX'%s",
argv[0], VTY_NEWLINE);
return CMD_WARNING;
}
}
cpu_record_print(vty, filter);
return CMD_SUCCESS;
}
/* List allocation and head/tail print out. */
static void
thread_list_debug (struct thread_list *list)
{
printf ("count [%d] head [%p] tail [%p]\n",
list->count, list->head, list->tail);
}
/* Debug print for thread_master. */
void
thread_master_debug (struct thread_master *m)
{
printf ("-----------\n");
printf ("readlist : ");
thread_list_debug (&m->read);
printf ("writelist : ");
thread_list_debug (&m->write);
printf ("timerlist : ");
thread_list_debug (&m->timer);
printf ("eventlist : ");
thread_list_debug (&m->event);
printf ("unuselist : ");
thread_list_debug (&m->unuse);
printf ("total alloc: [%ld]\n", m->alloc);
printf ("-----------\n");
}
/* Allocate new thread master. */
struct thread_master *
thread_master_create ()
{
if (cpu_record == NULL)
{
cpu_record = hash_create_size( 1011, cpu_record_hash_key, cpu_record_hash_cmp);
}
return (struct thread_master *) XCALLOC (MTYPE_THREAD_MASTER,
sizeof (struct thread_master));
}
/* Add a new thread to the list. */
static void
thread_list_add (struct thread_list *list, struct thread *thread)
{
thread->next = NULL;
thread->prev = list->tail;
if (list->tail)
list->tail->next = thread;
else
list->head = thread;
list->tail = thread;
list->count++;
}
/* Add a new thread just before the point. */
static void
thread_list_add_before (struct thread_list *list,
struct thread *point,
struct thread *thread)
{
thread->next = point;
thread->prev = point->prev;
if (point->prev)
point->prev->next = thread;
else
list->head = thread;
point->prev = thread;
list->count++;
}
/* Delete a thread from the list. */
static struct thread *
thread_list_delete (struct thread_list *list, struct thread *thread)
{
if (thread->next)
thread->next->prev = thread->prev;
else
list->tail = thread->prev;
if (thread->prev)
thread->prev->next = thread->next;
else
list->head = thread->next;
thread->next = thread->prev = NULL;
list->count--;
return thread;
}
/* Move thread to unuse list. */
static void
thread_add_unuse (struct thread_master *m, struct thread *thread)
{
assert (m != NULL);
assert (thread->next == NULL);
assert (thread->prev == NULL);
assert (thread->type == THREAD_UNUSED);
thread_list_add (&m->unuse, thread);
}
/* Free all unused thread. */
static void
thread_list_free (struct thread_master *m, struct thread_list *list)
{
struct thread *t;
struct thread *next;
for (t = list->head; t; t = next)
{
next = t->next;
XFREE (MTYPE_STRVEC, t->funcname);
XFREE (MTYPE_THREAD, t);
list->count--;
m->alloc--;
}
}
/* Stop thread scheduler. */
void
thread_master_free (struct thread_master *m)
{
thread_list_free (m, &m->read);
thread_list_free (m, &m->write);
thread_list_free (m, &m->timer);
thread_list_free (m, &m->event);
thread_list_free (m, &m->ready);
thread_list_free (m, &m->unuse);
XFREE (MTYPE_THREAD_MASTER, m);
}
/* Delete top of the list and return it. */
static struct thread *
thread_trim_head (struct thread_list *list)
{
if (list->head)
return thread_list_delete (list, list->head);
return NULL;
}
/* Thread list is empty or not. */
int
thread_empty (struct thread_list *list)
{
return list->head ? 0 : 1;
}
/* Return remain time in second. */
unsigned long
thread_timer_remain_second (struct thread *thread)
{
struct timeval timer_now;
gettimeofday (&timer_now, NULL);
if (thread->u.sands.tv_sec - timer_now.tv_sec > 0)
return thread->u.sands.tv_sec - timer_now.tv_sec;
else
return 0;
}
/* Trim blankspace and "()"s */
static char *
strip_funcname (char *funcname)
{
char buff[100];
char tmp, *ret, *e, *b = buff;
strncpy(buff, funcname, sizeof(buff));
buff[ sizeof(buff) -1] = '\0';
e = buff +strlen(buff) -1;
/* Wont work for funcname == "Word (explanation)" */
while (*b == ' ' || *b == '(')
++b;
while (*e == ' ' || *e == ')')
--e;
e++;
tmp = *e;
*e = '\0';
ret = XSTRDUP (MTYPE_STRVEC, b);
*e = tmp;
return ret;
}
/* Get new thread. */
static struct thread *
thread_get (struct thread_master *m, u_char type,
int (*func) (struct thread *), void *arg, char* funcname)
{
struct thread *thread;
if (m->unuse.head)
{
thread = thread_trim_head (&m->unuse);
if (thread->funcname)
XFREE(MTYPE_STRVEC, thread->funcname);
}
else
{
thread = XCALLOC (MTYPE_THREAD, sizeof (struct thread));
m->alloc++;
}
thread->type = type;
thread->add_type = type;
thread->master = m;
thread->func = func;
thread->arg = arg;
thread->funcname = strip_funcname(funcname);
return thread;
}
/* Add new read thread. */
struct thread *
funcname_thread_add_read (struct thread_master *m,
int (*func) (struct thread *), void *arg, int fd, char* funcname)
{
struct thread *thread;
assert (m != NULL);
if (FD_ISSET (fd, &m->readfd))
{
zlog (NULL, LOG_WARNING, "There is already read fd [%d]", fd);
return NULL;
}
thread = thread_get (m, THREAD_READ, func, arg, funcname);
FD_SET (fd, &m->readfd);
thread->u.fd = fd;
thread_list_add (&m->read, thread);
return thread;
}
/* Add new write thread. */
struct thread *
funcname_thread_add_write (struct thread_master *m,
int (*func) (struct thread *), void *arg, int fd, char* funcname)
{
struct thread *thread;
assert (m != NULL);
if (FD_ISSET (fd, &m->writefd))
{
zlog (NULL, LOG_WARNING, "There is already write fd [%d]", fd);
return NULL;
}
thread = thread_get (m, THREAD_WRITE, func, arg, funcname);
FD_SET (fd, &m->writefd);
thread->u.fd = fd;
thread_list_add (&m->write, thread);
return thread;
}
/* Add timer event thread. */
struct thread *
funcname_thread_add_timer (struct thread_master *m,
int (*func) (struct thread *), void *arg, long timer, char* funcname)
{
struct timeval timer_now;
struct thread *thread;
#ifndef TIMER_NO_SORT
struct thread *tt;
#endif /* TIMER_NO_SORT */
assert (m != NULL);
thread = thread_get (m, THREAD_TIMER, func, arg, funcname);
/* Do we need jitter here? */
gettimeofday (&timer_now, NULL);
timer_now.tv_sec += timer;
thread->u.sands = timer_now;
/* Sort by timeval. */
#ifdef TIMER_NO_SORT
thread_list_add (&m->timer, thread);
#else
for (tt = m->timer.head; tt; tt = tt->next)
if (timeval_cmp (thread->u.sands, tt->u.sands) <= 0)
break;
if (tt)
thread_list_add_before (&m->timer, tt, thread);
else
thread_list_add (&m->timer, thread);
#endif /* TIMER_NO_SORT */
return thread;
}
/* Add timer event thread with "millisecond" resolution */
struct thread *
funcname_thread_add_timer_msec (struct thread_master *m,
int (*func) (struct thread *), void *arg, long timer, char* funcname)
{
struct timeval timer_now;
struct thread *thread;
#ifndef TIMER_NO_SORT
struct thread *tt;
#endif /* TIMER_NO_SORT */
assert (m != NULL);
thread = thread_get (m, THREAD_TIMER, func, arg, funcname);
timer = 1000*timer; /* milli -> micro */
/* Do we need jitter here? */
gettimeofday (&timer_now, NULL);
timer_now.tv_sec += timer / TIMER_SECOND_MICRO;
timer_now.tv_usec += (timer % TIMER_SECOND_MICRO);
thread->u.sands = timer_now;
/* Sort by timeval. */
#ifdef TIMER_NO_SORT
thread_list_add (&m->timer, thread);
#else
for (tt = m->timer.head; tt; tt = tt->next)
if (timeval_cmp (thread->u.sands, tt->u.sands) <= 0)
break;
if (tt)
thread_list_add_before (&m->timer, tt, thread);
else
thread_list_add (&m->timer, thread);
#endif /* TIMER_NO_SORT */
return thread;
}
/* Add simple event thread. */
struct thread *
funcname_thread_add_event (struct thread_master *m,
int (*func) (struct thread *), void *arg, int val, char* funcname)
{
struct thread *thread;
assert (m != NULL);
thread = thread_get (m, THREAD_EVENT, func, arg, funcname);
thread->u.val = val;
thread_list_add (&m->event, thread);
return thread;
}
/* Cancel thread from scheduler. */
void
thread_cancel (struct thread *thread)
{
switch (thread->type)
{
case THREAD_READ:
assert (FD_ISSET (thread->u.fd, &thread->master->readfd));
FD_CLR (thread->u.fd, &thread->master->readfd);
thread_list_delete (&thread->master->read, thread);
break;
case THREAD_WRITE:
assert (FD_ISSET (thread->u.fd, &thread->master->writefd));
FD_CLR (thread->u.fd, &thread->master->writefd);
thread_list_delete (&thread->master->write, thread);
break;
case THREAD_TIMER:
thread_list_delete (&thread->master->timer, thread);
break;
case THREAD_EVENT:
thread_list_delete (&thread->master->event, thread);
break;
case THREAD_READY:
thread_list_delete (&thread->master->ready, thread);
break;
default:
break;
}
thread->type = THREAD_UNUSED;
thread_add_unuse (thread->master, thread);
}
/* Delete all events which has argument value arg. */
void
thread_cancel_event (struct thread_master *m, void *arg)
{
struct thread *thread;
thread = m->event.head;
while (thread)
{
struct thread *t;
t = thread;
thread = t->next;
if (t->arg == arg)
{
thread_list_delete (&m->event, t);
t->type = THREAD_UNUSED;
thread_add_unuse (m, t);
}
}
}
#ifdef TIMER_NO_SORT
struct timeval *
thread_timer_wait (struct thread_master *m, struct timeval *timer_val)
{
struct timeval timer_now;
struct timeval timer_min;
struct timeval *timer_wait;
gettimeofday (&timer_now, NULL);
timer_wait = NULL;
for (thread = m->timer.head; thread; thread = thread->next)
{
if (! timer_wait)
timer_wait = &thread->u.sands;
else if (timeval_cmp (thread->u.sands, *timer_wait) < 0)
timer_wait = &thread->u.sands;
}
if (m->timer.head)
{
timer_min = *timer_wait;
timer_min = timeval_subtract (timer_min, timer_now);
if (timer_min.tv_sec < 0)
{
timer_min.tv_sec = 0;
timer_min.tv_usec = 10;
}
timer_wait = &timer_min;
}
else
timer_wait = NULL;
if (timer_wait)
{
*timer_val = timer_wait;
return timer_val;
}
return NULL;
}
#else /* ! TIMER_NO_SORT */
struct timeval *
thread_timer_wait (struct thread_master *m, struct timeval *timer_val)
{
struct timeval timer_now;
struct timeval timer_min;
if (m->timer.head)
{
gettimeofday (&timer_now, NULL);
timer_min = m->timer.head->u.sands;
timer_min = timeval_subtract (timer_min, timer_now);
if (timer_min.tv_sec < 0)
{
timer_min.tv_sec = 0;
timer_min.tv_usec = 10;
}
*timer_val = timer_min;
return timer_val;
}
return NULL;
}
#endif /* TIMER_NO_SORT */
struct thread *
thread_run (struct thread_master *m, struct thread *thread,
struct thread *fetch)
{
*fetch = *thread;
thread->type = THREAD_UNUSED;
thread_add_unuse (m, thread);
return fetch;
}
int
thread_process_fd (struct thread_master *m, struct thread_list *list,
fd_set *fdset, fd_set *mfdset)
{
struct thread *thread;
struct thread *next;
int ready = 0;
for (thread = list->head; thread; thread = next)
{
next = thread->next;
if (FD_ISSET (THREAD_FD (thread), fdset))
{
assert (FD_ISSET (THREAD_FD (thread), mfdset));
FD_CLR(THREAD_FD (thread), mfdset);
thread_list_delete (list, thread);
thread_list_add (&m->ready, thread);
thread->type = THREAD_READY;
ready++;
}
}
return ready;
}
/* Fetch next ready thread. */
struct thread *
thread_fetch (struct thread_master *m, struct thread *fetch)
{
int num;
int ready;
struct thread *thread;
fd_set readfd;
fd_set writefd;
fd_set exceptfd;
struct timeval timer_now;
struct timeval timer_val;
struct timeval *timer_wait;
struct timeval timer_nowait;
timer_nowait.tv_sec = 0;
timer_nowait.tv_usec = 0;
while (1)
{
/* Signals are highest priority */
quagga_sigevent_process ();
/* Normal event are the next highest priority. */
if ((thread = thread_trim_head (&m->event)) != NULL)
return thread_run (m, thread, fetch);
/* Execute timer. */
gettimeofday (&timer_now, NULL);
for (thread = m->timer.head; thread; thread = thread->next)
if (timeval_cmp (timer_now, thread->u.sands) >= 0)
{
thread_list_delete (&m->timer, thread);
return thread_run (m, thread, fetch);
}
/* If there are any ready threads, process top of them. */
if ((thread = thread_trim_head (&m->ready)) != NULL)
return thread_run (m, thread, fetch);
/* Structure copy. */
readfd = m->readfd;
writefd = m->writefd;
exceptfd = m->exceptfd;
/* Calculate select wait timer. */
timer_wait = thread_timer_wait (m, &timer_val);
num = select (FD_SETSIZE, &readfd, &writefd, &exceptfd, timer_wait);
if (num == 0)
continue;
if (num < 0)
{
if (errno == EINTR)
{
/* signal received */
quagga_sigevent_process ();
continue;
}
zlog_warn ("select() error: %s", strerror (errno));
return NULL;
}
/* Normal priority read thead. */
ready = thread_process_fd (m, &m->read, &readfd, &m->readfd);
/* Write thead. */
ready = thread_process_fd (m, &m->write, &writefd, &m->writefd);
if ((thread = thread_trim_head (&m->ready)) != NULL)
return thread_run (m, thread, fetch);
}
}
static unsigned long
thread_consumed_time (RUSAGE_T *now, RUSAGE_T *start)
{
unsigned long thread_time;
#ifdef HAVE_RUSAGE
/* This is 'user + sys' time. */
thread_time = timeval_elapsed (now->ru_utime, start->ru_utime);
thread_time += timeval_elapsed (now->ru_stime, start->ru_stime);
#else
/* When rusage is not available, simple elapsed time is used. */
thread_time = timeval_elapsed (*now, *start);
#endif /* HAVE_RUSAGE */
return thread_time;
}
/* We should aim to yield after THREAD_YIELD_TIME_SLOT
milliseconds. */
int
thread_should_yield (struct thread *thread)
{
RUSAGE_T ru;
GETRUSAGE (&ru);
if (thread_consumed_time (&ru, &thread->ru) > THREAD_YIELD_TIME_SLOT)
return 1;
else
return 0;
}
/* We check thread consumed time. If the system has getrusage, we'll
use that to get indepth stats on the performance of the thread. If
not - we'll use gettimeofday for some guestimation. */
void
thread_call (struct thread *thread)
{
unsigned long thread_time;
RUSAGE_T ru;
struct cpu_thread_history tmp, *cpu;
tmp.func = thread->func;
tmp.funcname = thread->funcname;
cpu = hash_get(cpu_record, &tmp, cpu_record_hash_alloc);
GETRUSAGE (&thread->ru);
(*thread->func) (thread);
GETRUSAGE (&ru);
thread_time = thread_consumed_time (&ru, &thread->ru);
cpu->total += thread_time;
if (cpu->max < thread_time)
cpu->max = thread_time;
++cpu->total_calls;
cpu->types |= (1 << thread->add_type);
#ifdef THREAD_CONSUMED_TIME_CHECK
if (thread_time > 200000L)
{
/*
* We have a CPU Hog on our hands.
* Whinge about it now, so we're aware this is yet another task
* to fix.
*/
zlog_err ("CPU HOG task %s (%lx) ran for %ldms",
thread->funcname,
(unsigned long) thread->func,
thread_time / 1000L);
}
#endif /* THREAD_CONSUMED_TIME_CHECK */
}
/* Execute thread */
struct thread *
funcname_thread_execute (struct thread_master *m,
int (*func)(struct thread *),
void *arg,
int val,
char* funcname)
{
struct thread dummy;
memset (&dummy, 0, sizeof (struct thread));
dummy.type = THREAD_EVENT;
dummy.add_type = THREAD_EXECUTE;
dummy.master = NULL;
dummy.func = func;
dummy.arg = arg;
dummy.u.val = val;
dummy.funcname = strip_funcname (funcname);
thread_call (&dummy);
XFREE (MTYPE_STRVEC, dummy.funcname);
return NULL;
}