From a48b4e6d074a4e61ce9e8bf78fdb8ea9c57c6e64 Mon Sep 17 00:00:00 2001 From: paul Date: Fri, 22 Apr 2005 00:43:47 +0000 Subject: 2005-04-22 Paul Jakma * thread.h: Add background thread type and thread_add_background macro and accompanying funcname_... function. export thread_should_yield, background threads can use it. Lower thread yield time to 10ms, 100ms is noticeable lag and a thread would only be /starting/ to finish sometime afterward. * thread.c: (general) Add background thread type and schedule nearly all thread types through the ready list for fairness. (timeval_adjust) static qualifier missing (vty_out_cpu_thread_history) add support for printout of background threads (show_thread_cpu) ditto. (thread_master_debug) add debug of background list (thread_master_create) fixup long line (thread_add_unuse) add asserts for required state. (thread_master_free) free background thread list (funcname_thread_add_timer_timeval) make generic, able to support arbitrary timer-like thread types. (funcname_thread_add_timer) pass thread type to .._add_timer_timeval (funcname_thread_add_timer_msec) ditto (funcname_thread_add_background) Add a background thread, with an optional millisecond delay factor, using .._add_timer_timeval. (thread_cancel) Add background thread type. Move the thread_list_delete common to all cases to bottom of function, after the switch statement.. (thread_cancel_event) indent (thread_timer_wait) Static qualifier, and make it able to cope with arbitrary timer-like thread lists, so its of use to background threads too. (thread_process_fd) static qualifier. Again, make it take a list reference rather than thread_master. Fix indentation. (thread_timer_process) Check for ready timer-like threads in the given list and move them on to the ready list - code originally embedded in thread_fetch. (thread_fetch) Schedule all threads, other than events, through the ready list, to ensure fairness. Timer readying code moved to thread_timer_process so it can be reused for background threads. Remove the unneeded quagga_sigevent_process, as pointed out by John Lin . (thread_should_yield) make this available. --- lib/thread.c | 283 ++++++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 184 insertions(+), 99 deletions(-) (limited to 'lib/thread.c') diff --git a/lib/thread.c b/lib/thread.c index d1c925c4..33331242 100644 --- a/lib/thread.c +++ b/lib/thread.c @@ -35,7 +35,7 @@ static struct hash *cpu_record = NULL; /* Struct timeval's tv_usec one second value. */ #define TIMER_SECOND_MICRO 1000000L -struct timeval +static struct timeval timeval_adjust (struct timeval a) { while (a.tv_usec >= TIMER_SECOND_MICRO) @@ -87,7 +87,7 @@ timeval_elapsed (struct timeval a, struct timeval b) + (a.tv_usec - b.tv_usec)); } -static unsigned int +static unsigned int cpu_record_hash_key (struct cpu_thread_history *a) { return (unsigned int) a->func; @@ -114,7 +114,7 @@ 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", + vty_out(vty, " %7ld.%03ld %9d %8ld %10ld %c%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':' ', @@ -122,6 +122,7 @@ vty_out_cpu_thread_history(struct vty* vty, a->types & (1 << THREAD_TIMER) ? 'T':' ', a->types & (1 << THREAD_EVENT) ? 'E':' ', a->types & (1 << THREAD_EXECUTE) ? 'X':' ', + a->types & (1 << THREAD_BACKGROUND) ? 'B' : ' ', a->funcname, VTY_NEWLINE); } @@ -133,8 +134,7 @@ cpu_record_hash_print(struct hash_backet *bucket, 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; @@ -172,7 +172,7 @@ DEFUN(show_thread_cpu, SHOW_STR "Thread information\n" "Thread CPU usage\n" - "Display filter (rwtex)\n") + "Display filter (rwtexb)\n") { int i = 0; unsigned char filter = 0xff; @@ -204,6 +204,10 @@ DEFUN(show_thread_cpu, case 'X': filter |= (1 << THREAD_EXECUTE); break; + case 'b': + case 'B': + filter |= (1 << THREAD_BACKGROUND); + break; default: break; } @@ -211,7 +215,8 @@ DEFUN(show_thread_cpu, } if (filter == 0) { - vty_out(vty, "Invalid filter \"%s\" specified, must contain at least one of 'RWTEX'%s", + vty_out(vty, "Invalid filter \"%s\" specified," + " must contain at least one of 'RWTEXB'%s", argv[0], VTY_NEWLINE); return CMD_WARNING; } @@ -244,6 +249,8 @@ thread_master_debug (struct thread_master *m) thread_list_debug (&m->event); printf ("unuselist : "); thread_list_debug (&m->unuse); + printf ("bgndlist : "); + thread_list_debug (&m->background); printf ("total alloc: [%ld]\n", m->alloc); printf ("-----------\n"); } @@ -253,9 +260,9 @@ struct thread_master * thread_master_create () { if (cpu_record == NULL) - { - cpu_record = hash_create_size( 1011, cpu_record_hash_key, cpu_record_hash_cmp); - } + 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)); } @@ -311,7 +318,7 @@ thread_list_delete (struct thread_list *list, struct thread *thread) static void thread_add_unuse (struct thread_master *m, struct thread *thread) { - assert (m != NULL); + assert (m != NULL && thread != NULL); assert (thread->next == NULL); assert (thread->prev == NULL); assert (thread->type == THREAD_UNUSED); @@ -346,7 +353,8 @@ thread_master_free (struct thread_master *m) thread_list_free (m, &m->event); thread_list_free (m, &m->ready); thread_list_free (m, &m->unuse); - + thread_list_free (m, &m->background); + XFREE (MTYPE_THREAD_MASTER, m); } @@ -485,19 +493,36 @@ funcname_thread_add_write (struct thread_master *m, static struct thread * funcname_thread_add_timer_timeval (struct thread_master *m, int (*func) (struct thread *), + int type, void *arg, struct timeval *time_relative, const char* funcname) { struct thread *thread; struct timeval timer_now; + struct thread_list *list; #ifndef TIMER_NO_SORT struct thread *tt; #endif /* TIMER_NO_SORT */ assert (m != NULL); - thread = thread_get (m, THREAD_TIMER, func, arg, funcname); + assert (type == THREAD_TIMER || THREAD_BACKGROUND); + assert (time_relative); + + switch (type) + { + case THREAD_TIMER: + list = &m->timer; + break; + case THREAD_BACKGROUND: + list = &m->background; + break; + default: + return NULL; + } + + thread = thread_get (m, type, func, arg, funcname); /* Do we need jitter here? */ gettimeofday (&timer_now, NULL); @@ -508,16 +533,16 @@ funcname_thread_add_timer_timeval (struct thread_master *m, /* Sort by timeval. */ #ifdef TIMER_NO_SORT - thread_list_add (&m->timer, thread); + thread_list_add (list, thread); #else - for (tt = m->timer.head; tt; tt = tt->next) + for (tt = list->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); + thread_list_add_before (list, tt, thread); else - thread_list_add (&m->timer, thread); + thread_list_add (list, thread); #endif /* TIMER_NO_SORT */ return thread; @@ -537,7 +562,8 @@ funcname_thread_add_timer (struct thread_master *m, trel.tv_sec = timer; trel.tv_usec = 0; - return funcname_thread_add_timer_timeval (m, func, arg, &trel, funcname); + return funcname_thread_add_timer_timeval (m, func, THREAD_TIMER, arg, + &trel, funcname); } /* Add timer event thread with "millisecond" resolution */ @@ -553,7 +579,34 @@ funcname_thread_add_timer_msec (struct thread_master *m, trel.tv_sec = timer / 1000; trel.tv_usec = 1000*(timer % 1000); - return funcname_thread_add_timer_timeval (m, func, arg, &trel, funcname); + return funcname_thread_add_timer_timeval (m, func, THREAD_TIMER, + arg, &trel, funcname); +} + +/* Add a background thread, with an optional millisec delay */ +struct thread * +funcname_thread_add_background (struct thread_master *m, + int (*func) (struct thread *), + void *arg, long delay, + const char *funcname) +{ + struct timeval trel; + + assert (m != NULL); + + if (delay) + { + trel.tv_sec = delay / 1000; + trel.tv_usec = 1000*(delay % 1000); + } + else + { + trel.tv_sec = 0; + trel.tv_usec = 0; + } + + return funcname_thread_add_timer_timeval (m, func, THREAD_BACKGROUND, + arg, &trel, funcname); } /* Add simple event thread. */ @@ -576,30 +629,36 @@ funcname_thread_add_event (struct thread_master *m, void thread_cancel (struct thread *thread) { + struct thread_list *list; + 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); + list = &thread->master->read; 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); + list = &thread->master->write; break; case THREAD_TIMER: - thread_list_delete (&thread->master->timer, thread); + list = &thread->master->timer; break; case THREAD_EVENT: - thread_list_delete (&thread->master->event, thread); + list = &thread->master->event; break; case THREAD_READY: - thread_list_delete (&thread->master->ready, thread); + list = &thread->master->ready; break; + case THREAD_BACKGROUND: + list = &thread->master->background; default: + return; break; } + thread_list_delete (list, thread); thread->type = THREAD_UNUSED; thread_add_unuse (thread->master, thread); } @@ -619,17 +678,17 @@ thread_cancel_event (struct thread_master *m, void *arg) thread = t->next; if (t->arg == arg) - { - thread_list_delete (&m->event, t); - t->type = THREAD_UNUSED; - thread_add_unuse (m, t); - } + { + 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) +static struct timeval * +thread_timer_wait (struct thread_list *tlist, struct timeval *timer_val) { struct timeval timer_now; struct timeval timer_min; @@ -638,7 +697,7 @@ thread_timer_wait (struct thread_master *m, struct timeval *timer_val) gettimeofday (&timer_now, NULL); timer_wait = NULL; - for (thread = m->timer.head; thread; thread = thread->next) + for (thread = tlist->head; thread; thread = thread->next) { if (! timer_wait) timer_wait = &thread->u.sands; @@ -646,7 +705,7 @@ thread_timer_wait (struct thread_master *m, struct timeval *timer_val) timer_wait = &thread->u.sands; } - if (m->timer.head) + if (tlist->head) { timer_min = *timer_wait; timer_min = timeval_subtract (timer_min, timer_now); @@ -668,16 +727,16 @@ thread_timer_wait (struct thread_master *m, struct timeval *timer_val) return NULL; } #else /* ! TIMER_NO_SORT */ -struct timeval * -thread_timer_wait (struct thread_master *m, struct timeval *timer_val) +static struct timeval * +thread_timer_wait (struct thread_list *tlist, struct timeval *timer_val) { struct timeval timer_now; struct timeval timer_min; - if (m->timer.head) + if (tlist->head) { gettimeofday (&timer_now, NULL); - timer_min = m->timer.head->u.sands; + timer_min = tlist->head->u.sands; timer_min = timeval_subtract (timer_min, timer_now); if (timer_min.tv_sec < 0) { @@ -701,105 +760,140 @@ thread_run (struct thread_master *m, struct thread *thread, return fetch; } -int -thread_process_fd (struct thread_master *m, struct thread_list *list, - fd_set *fdset, fd_set *mfdset) +static int +thread_process_fd (struct thread_list *list, fd_set *fdset, fd_set *mfdset) { struct thread *thread; struct thread *next; int ready = 0; - + + assert (list); + 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++; - } + { + assert (FD_ISSET (THREAD_FD (thread), mfdset)); + FD_CLR(THREAD_FD (thread), mfdset); + thread_list_delete (list, thread); + thread_list_add (&thread->master->ready, thread); + thread->type = THREAD_READY; + ready++; + } } return ready; } +/* fetch next timer-like thread thread from the list and return it */ +static unsigned int +thread_timer_process (struct thread_list *list, struct timeval *timenow) +{ + struct thread *thread; + unsigned int ready = 0; + + assert (list && timenow); + + for (thread = list->head; thread; thread = thread->next) + if (timeval_cmp (*timenow, thread->u.sands) >= 0) + { + thread_list_delete (list, thread); + assert (thread->next == thread->prev && thread->next == NULL); + thread->next = thread->prev = NULL; + thread->type = THREAD_READY; + thread_list_add (&thread->master->ready, thread); + 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_val_bg; struct timeval *timer_wait; - struct timeval timer_nowait; - - timer_nowait.tv_sec = 0; - timer_nowait.tv_usec = 0; + struct timeval *timer_wait_bg; while (1) { + int num = 0; + int ready = m->ready.count; + /* 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. */ + + /* Timer threads */ + ready += thread_timer_process (&m->timer, &timer_now); + + /* If there are any ready threads from previous scheduler runs, + * 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); - + + /* Calculate select wait timer if nothing else to do */ + if (ready == 0) + { + timer_wait = thread_timer_wait (&m->timer, &timer_val); + timer_wait_bg = thread_timer_wait (&m->background, &timer_val_bg); + + if (timer_wait && timer_wait_bg && + (timeval_cmp (*timer_wait, *timer_wait_bg) > 0)) + timer_wait = timer_wait_bg; + else if (!timer_wait && timer_wait_bg) + timer_wait = timer_wait_bg; + } + else + { + timer_val.tv_sec = timer_val.tv_usec = 0; + timer_wait = &timer_val; + } + num = select (FD_SETSIZE, &readfd, &writefd, &exceptfd, timer_wait); - - if (num == 0) - continue; - + + /* Signals should get quick treatment */ if (num < 0) { if (errno == EINTR) - { - /* signal received */ - quagga_sigevent_process (); - continue; - } - + continue; /* signal received - process it */ zlog_warn ("select() error: %s", safe_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) + + /* Got IO, process it */ + if (num > 0) + { + /* Normal priority read thead. */ + ready += thread_process_fd (&m->read, &readfd, &m->readfd); + /* Write thead. */ + ready += thread_process_fd (&m->write, &writefd, &m->writefd); + } + + /* Background timer/events, lowest priority */ + ready += thread_timer_process (&m->background, &timer_now); + + /* if any threads were made ready above.. */ + if ((ready > 0) && (thread = thread_trim_head (&m->ready)) != NULL) return thread_run (m, thread, fetch); } } @@ -821,10 +915,6 @@ thread_consumed_time (RUSAGE_T *now, RUSAGE_T *start) return thread_time; } -#if 0 - -/* This function is not currently used: threads never yield! */ - /* We should aim to yield after THREAD_YIELD_TIME_SLOT milliseconds. */ int @@ -833,15 +923,10 @@ 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; + + return (thread_consumed_time (&ru, &thread->ru) > THREAD_YIELD_TIME_SLOT); } -#endif - /* 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. */ -- cgit v1.2.1