[ViewVC] Diff of: cvs/Coro/Coro.pm

Comparing Coro/Coro.pm (file contents):
Revision 1.121 by root, Fri Apr 13 12:56:55 2007 UTC vs.
Revision 1.144 by root, Wed Oct 3 01:48:05 2007 UTC

…		…
20		20
21	=head1 DESCRIPTION	21	=head1 DESCRIPTION
22		22
23	This module collection manages coroutines. Coroutines are similar	23	This module collection manages coroutines. Coroutines are similar
24	to threads but don't run in parallel at the same time even on SMP	24	to threads but don't run in parallel at the same time even on SMP
25	machines. The specific flavor of coroutine use din this module also	25	machines. The specific flavor of coroutine used in this module also
26	guarentees you that it will not switch between coroutines unless	26	guarantees you that it will not switch between coroutines unless
27	necessary, at easily-identified points in your program, so locking and	27	necessary, at easily-identified points in your program, so locking and
28	parallel access are rarely an issue, making coroutine programming much	28	parallel access are rarely an issue, making coroutine programming much
29	safer than threads programming.	29	safer than threads programming.
30		30
31	(Perl, however, does not natively support real threads but instead does a	31	(Perl, however, does not natively support real threads but instead does a
…		…
50		50
51	our $idle; # idle handler	51	our $idle; # idle handler
52	our $main; # main coroutine	52	our $main; # main coroutine
53	our $current; # current coroutine	53	our $current; # current coroutine
54		54
55	our $VERSION = '3.56';	55	our $VERSION = '4.0';
56		56
57	our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub);	57	our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub);
58	our %EXPORT_TAGS = (	58	our %EXPORT_TAGS = (
59	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],	59	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
60	);	60	);
…		…
108		108
109	The current coroutine (the last coroutine switched to). The initial value	109	The current coroutine (the last coroutine switched to). The initial value
110	is C<$main> (of course).	110	is C<$main> (of course).
111		111
112	This variable is B<strictly> I<read-only>. It is provided for performance	112	This variable is B<strictly> I<read-only>. It is provided for performance
113	reasons. If performance is not essentiel you are encouraged to use the	113	reasons. If performance is not essential you are encouraged to use the
114	C<Coro::current> function instead.	114	C<Coro::current> function instead.
115		115
116	=cut	116	=cut
117		117
		118	$main->{desc} = "[main::]";
		119
118	# maybe some other module used Coro::Specific before...	120	# maybe some other module used Coro::Specific before...
119	$main->{specific} = $current->{specific}	121	$main->{_specific} = $current->{_specific}
120	if $current;	122	if $current;
121		123
122	_set_current $main;	124	_set_current $main;
123		125
124	sub current() { $current }	126	sub current() { $current }
…		…
149	# free coroutine data and mark as destructed	151	# free coroutine data and mark as destructed
150	$self->_destroy	152	$self->_destroy
151	or return;	153	or return;
152		154
153	# call all destruction callbacks	155	# call all destruction callbacks
154	$_->(@{$self->{status}})	156	$_->(@{$self->{_status}})
155	for @{(delete $self->{destroy_cb}) \|\| []};	157	for @{(delete $self->{_on_destroy}) \|\| []};
156	}	158	}
157		159
158	# this coroutine is necessary because a coroutine	160	# this coroutine is necessary because a coroutine
159	# cannot destroy itself.	161	# cannot destroy itself.
160	my @destroy;	162	my @destroy;
…		…
166	while @destroy;	168	while @destroy;
167		169
168	&schedule;	170	&schedule;
169	}	171	}
170	};	172	};
171		173	$manager->desc ("[coro manager]");
172	$manager->prio (PRIO_MAX);	174	$manager->prio (PRIO_MAX);
173		175
174	# static methods. not really.	176	# static methods. not really.
175		177
176	=back	178	=back
…		…
185		187
186	Create a new asynchronous coroutine and return it's coroutine object	188	Create a new asynchronous coroutine and return it's coroutine object
187	(usually unused). When the sub returns the new coroutine is automatically	189	(usually unused). When the sub returns the new coroutine is automatically
188	terminated.	190	terminated.
189		191
190	Calling C<exit> in a coroutine will try to do the same as calling exit	192	Calling C<exit> in a coroutine will do the same as calling exit outside
191	outside the coroutine, but this is experimental. It is best not to rely on	193	the coroutine. Likewise, when the coroutine dies, the program will exit,
192	exit doing any cleanups or even not crashing.	194	just as it would in the main program.
193
194	When the coroutine dies, the program will exit, just as in the main
195	program.
196		195
197	# create a new coroutine that just prints its arguments	196	# create a new coroutine that just prints its arguments
198	async {	197	async {
199	print "@_\n";	198	print "@_\n";
200	} 1,2,3,4;	199	} 1,2,3,4;
…		…
225	The pool size is limited to 8 idle coroutines (this can be adjusted by	224	The pool size is limited to 8 idle coroutines (this can be adjusted by
226	changing $Coro::POOL_SIZE), and there can be as many non-idle coros as	225	changing $Coro::POOL_SIZE), and there can be as many non-idle coros as
227	required.	226	required.
228		227
229	If you are concerned about pooled coroutines growing a lot because a	228	If you are concerned about pooled coroutines growing a lot because a
230	single C<async_pool> used a lot of stackspace you can e.g. C<async_pool {	229	single C<async_pool> used a lot of stackspace you can e.g. C<async_pool
231	terminate }> once per second or so to slowly replenish the pool.	230	{ terminate }> once per second or so to slowly replenish the pool. In
		231	addition to that, when the stacks used by a handler grows larger than 16kb
		232	(adjustable with $Coro::POOL_RSS) it will also exit.
232		233
233	=cut	234	=cut
234		235
235	our $POOL_SIZE = 8;	236	our $POOL_SIZE = 8;
		237	our $POOL_RSS = 16 * 1024;
236	our @pool;	238	our @async_pool;
237		239
238	sub pool_handler {	240	sub pool_handler {
		241	my $cb;
		242
239	while () {	243	while () {
240	eval {	244	eval {
241	my ($cb, @arg) = @{ delete $current->{_invoke} or return };	245	while () {
242	$cb->(@arg);	246	_pool_1 $cb;
		247	&$cb;
		248	_pool_2 $cb;
		249	&schedule;
		250	}
243	};	251	};
		252
		253	last if $@ eq "\3terminate\2\n";
244	warn $@ if $@;	254	warn $@ if $@;
245
246	last if @pool >= $POOL_SIZE;
247	push @pool, $current;
248
249	$current->save (Coro::State::SAVE_DEF);
250	$current->prio (0);
251	schedule;
252	}	255	}
253	}	256	}
254		257
255	sub async_pool(&@) {	258	sub async_pool(&@) {
256	# this is also inlined into the unlock_scheduler	259	# this is also inlined into the unlock_scheduler
257	my $coro = (pop @pool or new Coro \&pool_handler);	260	my $coro = (pop @async_pool) \|\| new Coro \&pool_handler;
258		261
259	$coro->{_invoke} = [@_];	262	$coro->{_invoke} = [@_];
260	$coro->ready;	263	$coro->ready;
261		264
262	$coro	265	$coro
…		…
280	# wake up sleeping coroutine	283	# wake up sleeping coroutine
281	$current->ready;	284	$current->ready;
282	undef $current;	285	undef $current;
283	};	286	};
284		287
285	# call schedule until event occured.	288	# call schedule until event occurred.
286	# in case we are woken up for other reasons	289	# in case we are woken up for other reasons
287	# (current still defined), loop.	290	# (current still defined), loop.
288	Coro::schedule while $current;	291	Coro::schedule while $current;
289	}	292	}
290		293
…		…
305		308
306	=item terminate [arg...]	309	=item terminate [arg...]
307		310
308	Terminates the current coroutine with the given status values (see L<cancel>).	311	Terminates the current coroutine with the given status values (see L<cancel>).
309		312
		313	=item killall
		314
		315	Kills/terminates/cancels all coroutines except the currently running
		316	one. This is useful after a fork, either in the child or the parent, as
		317	usually only one of them should inherit the running coroutines.
		318
310	=cut	319	=cut
311		320
312	sub terminate {	321	sub terminate {
313	$current->cancel (@_);	322	$current->cancel (@_);
		323	}
		324
		325	sub killall {
		326	for (Coro::State::list) {
		327	$_->cancel
		328	if $_ != $current && UNIVERSAL::isa $_, "Coro";
		329	}
314	}	330	}
315		331
316	=back	332	=back
317		333
318	# dynamic methods	334	# dynamic methods
…		…
362		378
363	=cut	379	=cut
364		380
365	sub cancel {	381	sub cancel {
366	my $self = shift;	382	my $self = shift;
367	$self->{status} = [@_];	383	$self->{_status} = [@_];
368		384
369	if ($current == $self) {	385	if ($current == $self) {
370	push @destroy, $self;	386	push @destroy, $self;
371	$manager->ready;	387	$manager->ready;
372	&schedule while 1;	388	&schedule while 1;
…		…
376	}	392	}
377		393
378	=item $coroutine->join	394	=item $coroutine->join
379		395
380	Wait until the coroutine terminates and return any values given to the	396	Wait until the coroutine terminates and return any values given to the
381	C<terminate> or C<cancel> functions. C<join> can be called multiple times	397	C<terminate> or C<cancel> functions. C<join> can be called concurrently
382	from multiple coroutine.	398	from multiple coroutines.
383		399
384	=cut	400	=cut
385		401
386	sub join {	402	sub join {
387	my $self = shift;	403	my $self = shift;
388		404
389	unless ($self->{status}) {	405	unless ($self->{_status}) {
390	my $current = $current;	406	my $current = $current;
391		407
392	push @{$self->{destroy_cb}}, sub {	408	push @{$self->{_on_destroy}}, sub {
393	$current->ready;	409	$current->ready;
394	undef $current;	410	undef $current;
395	};	411	};
396		412
397	&schedule while $current;	413	&schedule while $current;
398	}	414	}
399		415
400	wantarray ? @{$self->{status}} : $self->{status}[0];	416	wantarray ? @{$self->{_status}} : $self->{_status}[0];
401	}	417	}
402		418
403	=item $coroutine->on_destroy (\&cb)	419	=item $coroutine->on_destroy (\&cb)
404		420
405	Registers a callback that is called when this coroutine gets destroyed,	421	Registers a callback that is called when this coroutine gets destroyed,
…		…
409	=cut	425	=cut
410		426
411	sub on_destroy {	427	sub on_destroy {
412	my ($self, $cb) = @_;	428	my ($self, $cb) = @_;
413		429
414	push @{ $self->{destroy_cb} }, $cb;	430	push @{ $self->{_on_destroy} }, $cb;
415	}	431	}
416		432
417	=item $oldprio = $coroutine->prio ($newprio)	433	=item $oldprio = $coroutine->prio ($newprio)
418		434
419	Sets (or gets, if the argument is missing) the priority of the	435	Sets (or gets, if the argument is missing) the priority of the
…		…
444	=item $olddesc = $coroutine->desc ($newdesc)	460	=item $olddesc = $coroutine->desc ($newdesc)
445		461
446	Sets (or gets in case the argument is missing) the description for this	462	Sets (or gets in case the argument is missing) the description for this
447	coroutine. This is just a free-form string you can associate with a coroutine.	463	coroutine. This is just a free-form string you can associate with a coroutine.
448		464
		465	This method simply sets the C<< $coroutine->{desc} >> member to the given string. You
		466	can modify this member directly if you wish.
		467
449	=cut	468	=cut
450		469
451	sub desc {	470	sub desc {
452	my $old = $_[0]{desc};	471	my $old = $_[0]{desc};
453	$_[0]{desc} = $_[1] if @_ > 1;	472	$_[0]{desc} = $_[1] if @_ > 1;
…		…
461	=over 4	480	=over 4
462		481
463	=item Coro::nready	482	=item Coro::nready
464		483
465	Returns the number of coroutines that are currently in the ready state,	484	Returns the number of coroutines that are currently in the ready state,
466	i.e. that can be swicthed to. The value C<0> means that the only runnable	485	i.e. that can be switched to. The value C<0> means that the only runnable
467	coroutine is the currently running one, so C<cede> would have no effect,	486	coroutine is the currently running one, so C<cede> would have no effect,
468	and C<schedule> would cause a deadlock unless there is an idle handler	487	and C<schedule> would cause a deadlock unless there is an idle handler
469	that wakes up some coroutines.	488	that wakes up some coroutines.
470		489
471	=item my $guard = Coro::guard { ... }	490	=item my $guard = Coro::guard { ... }
…		…
507	This utility function takes a BLOCK or code reference and "unblocks" it,	526	This utility function takes a BLOCK or code reference and "unblocks" it,
508	returning the new coderef. This means that the new coderef will return	527	returning the new coderef. This means that the new coderef will return
509	immediately without blocking, returning nothing, while the original code	528	immediately without blocking, returning nothing, while the original code
510	ref will be called (with parameters) from within its own coroutine.	529	ref will be called (with parameters) from within its own coroutine.
511		530
512	The reason this fucntion exists is that many event libraries (such as the	531	The reason this function exists is that many event libraries (such as the
513	venerable L<Event\|Event> module) are not coroutine-safe (a weaker form	532	venerable L<Event\|Event> module) are not coroutine-safe (a weaker form
514	of thread-safety). This means you must not block within event callbacks,	533	of thread-safety). This means you must not block within event callbacks,
515	otherwise you might suffer from crashes or worse.	534	otherwise you might suffer from crashes or worse.
516		535
517	This function allows your callbacks to block by executing them in another	536	This function allows your callbacks to block by executing them in another
…		…
528		547
529	# we create a special coro because we want to cede,	548	# we create a special coro because we want to cede,
530	# to reduce pressure on the coro pool (because most callbacks	549	# to reduce pressure on the coro pool (because most callbacks
531	# return immediately and can be reused) and because we cannot cede	550	# return immediately and can be reused) and because we cannot cede
532	# inside an event callback.	551	# inside an event callback.
533	our $unblock_scheduler = async {	552	our $unblock_scheduler = new Coro sub {
534	while () {	553	while () {
535	while (my $cb = pop @unblock_queue) {	554	while (my $cb = pop @unblock_queue) {
536	# this is an inlined copy of async_pool	555	# this is an inlined copy of async_pool
537	my $coro = (pop @pool or new Coro \&pool_handler);	556	my $coro = (pop @async_pool) \|\| new Coro \&pool_handler;
538		557
539	$coro->{_invoke} = $cb;	558	$coro->{_invoke} = $cb;
540	$coro->ready;	559	$coro->ready;
541	cede; # for short-lived callbacks, this reduces pressure on the coro pool	560	cede; # for short-lived callbacks, this reduces pressure on the coro pool
542	}	561	}
543	schedule; # sleep well	562	schedule; # sleep well
544	}	563	}
545	};	564	};
		565	$unblock_scheduler->desc ("[unblock_sub scheduler]");
546		566
547	sub unblock_sub(&) {	567	sub unblock_sub(&) {
548	my $cb = shift;	568	my $cb = shift;
549		569
550	sub {	570	sub {
…		…
563		583
564	- you must make very sure that no coro is still active on global	584	- you must make very sure that no coro is still active on global
565	destruction. very bad things might happen otherwise (usually segfaults).	585	destruction. very bad things might happen otherwise (usually segfaults).
566		586
567	- this module is not thread-safe. You should only ever use this module	587	- this module is not thread-safe. You should only ever use this module
568	from the same thread (this requirement might be losened in the future	588	from the same thread (this requirement might be loosened in the future
569	to allow per-thread schedulers, but Coro::State does not yet allow	589	to allow per-thread schedulers, but Coro::State does not yet allow
570	this).	590	this).
571		591
572	=head1 SEE ALSO	592	=head1 SEE ALSO
573		593

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Comparing Coro/Coro.pm (file contents): Revision 1.121 by root, Fri Apr 13 12:56:55 2007 UTC vs. Revision 1.144 by root, Wed Oct 3 01:48:05 2007 UTC

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Comparing Coro/Coro.pm (file contents):
Revision 1.121 by root, Fri Apr 13 12:56:55 2007 UTC vs.
Revision 1.144 by root, Wed Oct 3 01:48:05 2007 UTC