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

Comparing Coro/Coro.pm (file contents):
Revision 1.107 by root, Fri Jan 5 18:25:51 2007 UTC vs.
Revision 1.145 by root, Wed Oct 3 16:03:17 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 = '3.3';	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 not work correctly, so do not do that.	192	See the C<Coro::State::new> constructor for info about the coroutine
		193	environment.
191		194
192	When the coroutine dies, the program will exit, just as in the main	195	Calling C<exit> in a coroutine will do the same as calling exit outside
193	program.	196	the coroutine. Likewise, when the coroutine dies, the program will exit,
		197	just as it would in the main program.
194		198
195	# create a new coroutine that just prints its arguments	199	# create a new coroutine that just prints its arguments
196	async {	200	async {
197	print "@_\n";	201	print "@_\n";
198	} 1,2,3,4;	202	} 1,2,3,4;
…		…
210	Similar to C<async>, but uses a coroutine pool, so you should not call	214	Similar to C<async>, but uses a coroutine pool, so you should not call
211	terminate or join (although you are allowed to), and you get a coroutine	215	terminate or join (although you are allowed to), and you get a coroutine
212	that might have executed other code already (which can be good or bad :).	216	that might have executed other code already (which can be good or bad :).
213		217
214	Also, the block is executed in an C<eval> context and a warning will be	218	Also, the block is executed in an C<eval> context and a warning will be
215	issued in case of an exception instead of terminating the program, as C<async> does.	219	issued in case of an exception instead of terminating the program, as
		220	C<async> does. As the coroutine is being reused, stuff like C<on_destroy>
		221	will not work in the expected way, unless you call terminate or cancel,
		222	which somehow defeats the purpose of pooling.
216		223
217	The priority will be reset to C<0> after each job, otherwise the coroutine	224	The priority will be reset to C<0> after each job, otherwise the coroutine
218	will be re-used "as-is".	225	will be re-used "as-is".
219		226
220	The pool size is limited to 8 idle coroutines (this can be adjusted by	227	The pool size is limited to 8 idle coroutines (this can be adjusted by
221	changing $Coro::POOL_SIZE), and there can be as many non-idle coros as	228	changing $Coro::POOL_SIZE), and there can be as many non-idle coros as
222	required.	229	required.
223		230
224	If you are concerned about pooled coroutines growing a lot because a	231	If you are concerned about pooled coroutines growing a lot because a
225	single C<async_pool> used a lot of stackspace you can e.g. C<async_pool {	232	single C<async_pool> used a lot of stackspace you can e.g. C<async_pool
226	terminate }> once per second or so to slowly replenish the pool.	233	{ terminate }> once per second or so to slowly replenish the pool. In
		234	addition to that, when the stacks used by a handler grows larger than 16kb
		235	(adjustable with $Coro::POOL_RSS) it will also exit.
227		236
228	=cut	237	=cut
229		238
230	our $POOL_SIZE = 8;	239	our $POOL_SIZE = 8;
		240	our $POOL_RSS = 16 * 1024;
231	our @pool;	241	our @async_pool;
232		242
233	sub pool_handler {	243	sub pool_handler {
		244	my $cb;
		245
234	while () {	246	while () {
235	my ($cb, @arg) = @{ delete $current->{_invoke} };
236
237	eval {	247	eval {
238	$cb->(@arg);	248	while () {
		249	_pool_1 $cb;
		250	&$cb;
		251	_pool_2 $cb;
		252	&schedule;
		253	}
239	};	254	};
		255
		256	last if $@ eq "\3terminate\2\n";
240	warn $@ if $@;	257	warn $@ if $@;
241
242	last if @pool >= $POOL_SIZE;
243	push @pool, $current;
244
245	$current->prio (0);
246	schedule;
247	}	258	}
248	}	259	}
249		260
250	sub async_pool(&@) {	261	sub async_pool(&@) {
251	# this is also inlined into the unlock_scheduler	262	# this is also inlined into the unlock_scheduler
252	my $coro = (pop @pool or new Coro \&pool_handler);	263	my $coro = (pop @async_pool) \|\| new Coro \&pool_handler;
253		264
254	$coro->{_invoke} = [@_];	265	$coro->{_invoke} = [@_];
255	$coro->ready;	266	$coro->ready;
256		267
257	$coro	268	$coro
…		…
275	# wake up sleeping coroutine	286	# wake up sleeping coroutine
276	$current->ready;	287	$current->ready;
277	undef $current;	288	undef $current;
278	};	289	};
279		290
280	# call schedule until event occured.	291	# call schedule until event occurred.
281	# in case we are woken up for other reasons	292	# in case we are woken up for other reasons
282	# (current still defined), loop.	293	# (current still defined), loop.
283	Coro::schedule while $current;	294	Coro::schedule while $current;
284	}	295	}
285		296
…		…
300		311
301	=item terminate [arg...]	312	=item terminate [arg...]
302		313
303	Terminates the current coroutine with the given status values (see L<cancel>).	314	Terminates the current coroutine with the given status values (see L<cancel>).
304		315
		316	=item killall
		317
		318	Kills/terminates/cancels all coroutines except the currently running
		319	one. This is useful after a fork, either in the child or the parent, as
		320	usually only one of them should inherit the running coroutines.
		321
305	=cut	322	=cut
306		323
307	sub terminate {	324	sub terminate {
308	$current->cancel (@_);	325	$current->cancel (@_);
		326	}
		327
		328	sub killall {
		329	for (Coro::State::list) {
		330	$_->cancel
		331	if $_ != $current && UNIVERSAL::isa $_, "Coro";
		332	}
309	}	333	}
310		334
311	=back	335	=back
312		336
313	# dynamic methods	337	# dynamic methods
…		…
323	Create a new coroutine and return it. When the sub returns the coroutine	347	Create a new coroutine and return it. When the sub returns the coroutine
324	automatically terminates as if C<terminate> with the returned values were	348	automatically terminates as if C<terminate> with the returned values were
325	called. To make the coroutine run you must first put it into the ready queue	349	called. To make the coroutine run you must first put it into the ready queue
326	by calling the ready method.	350	by calling the ready method.
327		351
328	Calling C<exit> in a coroutine will not work correctly, so do not do that.	352	See C<async> and C<Coro::State::new> for additional info about the
		353	coroutine environment.
329		354
330	=cut	355	=cut
331		356
332	sub _run_coro {	357	sub _run_coro {
333	terminate &{+shift};	358	terminate &{+shift};
…		…
357		382
358	=cut	383	=cut
359		384
360	sub cancel {	385	sub cancel {
361	my $self = shift;	386	my $self = shift;
362	$self->{status} = [@_];	387	$self->{_status} = [@_];
363		388
364	if ($current == $self) {	389	if ($current == $self) {
365	push @destroy, $self;	390	push @destroy, $self;
366	$manager->ready;	391	$manager->ready;
367	&schedule while 1;	392	&schedule while 1;
…		…
371	}	396	}
372		397
373	=item $coroutine->join	398	=item $coroutine->join
374		399
375	Wait until the coroutine terminates and return any values given to the	400	Wait until the coroutine terminates and return any values given to the
376	C<terminate> or C<cancel> functions. C<join> can be called multiple times	401	C<terminate> or C<cancel> functions. C<join> can be called concurrently
377	from multiple coroutine.	402	from multiple coroutines.
378		403
379	=cut	404	=cut
380		405
381	sub join {	406	sub join {
382	my $self = shift;	407	my $self = shift;
383		408
384	unless ($self->{status}) {	409	unless ($self->{_status}) {
385	my $current = $current;	410	my $current = $current;
386		411
387	push @{$self->{destroy_cb}}, sub {	412	push @{$self->{_on_destroy}}, sub {
388	$current->ready;	413	$current->ready;
389	undef $current;	414	undef $current;
390	};	415	};
391		416
392	&schedule while $current;	417	&schedule while $current;
393	}	418	}
394		419
395	wantarray ? @{$self->{status}} : $self->{status}[0];	420	wantarray ? @{$self->{_status}} : $self->{_status}[0];
396	}	421	}
397		422
398	=item $coroutine->on_destroy (\&cb)	423	=item $coroutine->on_destroy (\&cb)
399		424
400	Registers a callback that is called when this coroutine gets destroyed,	425	Registers a callback that is called when this coroutine gets destroyed,
…		…
404	=cut	429	=cut
405		430
406	sub on_destroy {	431	sub on_destroy {
407	my ($self, $cb) = @_;	432	my ($self, $cb) = @_;
408		433
409	push @{ $self->{destroy_cb} }, $cb;	434	push @{ $self->{_on_destroy} }, $cb;
410	}	435	}
411		436
412	=item $oldprio = $coroutine->prio ($newprio)	437	=item $oldprio = $coroutine->prio ($newprio)
413		438
414	Sets (or gets, if the argument is missing) the priority of the	439	Sets (or gets, if the argument is missing) the priority of the
…		…
439	=item $olddesc = $coroutine->desc ($newdesc)	464	=item $olddesc = $coroutine->desc ($newdesc)
440		465
441	Sets (or gets in case the argument is missing) the description for this	466	Sets (or gets in case the argument is missing) the description for this
442	coroutine. This is just a free-form string you can associate with a coroutine.	467	coroutine. This is just a free-form string you can associate with a coroutine.
443		468
		469	This method simply sets the C<< $coroutine->{desc} >> member to the given string. You
		470	can modify this member directly if you wish.
		471
444	=cut	472	=cut
445		473
446	sub desc {	474	sub desc {
447	my $old = $_[0]{desc};	475	my $old = $_[0]{desc};
448	$_[0]{desc} = $_[1] if @_ > 1;	476	$_[0]{desc} = $_[1] if @_ > 1;
…		…
456	=over 4	484	=over 4
457		485
458	=item Coro::nready	486	=item Coro::nready
459		487
460	Returns the number of coroutines that are currently in the ready state,	488	Returns the number of coroutines that are currently in the ready state,
461	i.e. that can be swicthed to. The value C<0> means that the only runnable	489	i.e. that can be switched to. The value C<0> means that the only runnable
462	coroutine is the currently running one, so C<cede> would have no effect,	490	coroutine is the currently running one, so C<cede> would have no effect,
463	and C<schedule> would cause a deadlock unless there is an idle handler	491	and C<schedule> would cause a deadlock unless there is an idle handler
464	that wakes up some coroutines.	492	that wakes up some coroutines.
465		493
466	=item my $guard = Coro::guard { ... }	494	=item my $guard = Coro::guard { ... }
467		495
468	This creates and returns a guard object. Nothing happens until the objetc	496	This creates and returns a guard object. Nothing happens until the object
469	gets destroyed, in which case the codeblock given as argument will be	497	gets destroyed, in which case the codeblock given as argument will be
470	executed. This is useful to free locks or other resources in case of a	498	executed. This is useful to free locks or other resources in case of a
471	runtime error or when the coroutine gets canceled, as in both cases the	499	runtime error or when the coroutine gets canceled, as in both cases the
472	guard block will be executed. The guard object supports only one method,	500	guard block will be executed. The guard object supports only one method,
473	C<< ->cancel >>, which will keep the codeblock from being executed.	501	C<< ->cancel >>, which will keep the codeblock from being executed.
…		…
502	This utility function takes a BLOCK or code reference and "unblocks" it,	530	This utility function takes a BLOCK or code reference and "unblocks" it,
503	returning the new coderef. This means that the new coderef will return	531	returning the new coderef. This means that the new coderef will return
504	immediately without blocking, returning nothing, while the original code	532	immediately without blocking, returning nothing, while the original code
505	ref will be called (with parameters) from within its own coroutine.	533	ref will be called (with parameters) from within its own coroutine.
506		534
507	The reason this fucntion exists is that many event libraries (such as the	535	The reason this function exists is that many event libraries (such as the
508	venerable L<Event\|Event> module) are not coroutine-safe (a weaker form	536	venerable L<Event\|Event> module) are not coroutine-safe (a weaker form
509	of thread-safety). This means you must not block within event callbacks,	537	of thread-safety). This means you must not block within event callbacks,
510	otherwise you might suffer from crashes or worse.	538	otherwise you might suffer from crashes or worse.
511		539
512	This function allows your callbacks to block by executing them in another	540	This function allows your callbacks to block by executing them in another
…		…
523		551
524	# we create a special coro because we want to cede,	552	# we create a special coro because we want to cede,
525	# to reduce pressure on the coro pool (because most callbacks	553	# to reduce pressure on the coro pool (because most callbacks
526	# return immediately and can be reused) and because we cannot cede	554	# return immediately and can be reused) and because we cannot cede
527	# inside an event callback.	555	# inside an event callback.
528	our $unblock_scheduler = async {	556	our $unblock_scheduler = new Coro sub {
529	while () {	557	while () {
530	while (my $cb = pop @unblock_queue) {	558	while (my $cb = pop @unblock_queue) {
531	# this is an inlined copy of async_pool	559	# this is an inlined copy of async_pool
532	my $coro = (pop @pool or new Coro \&pool_handler);	560	my $coro = (pop @async_pool) \|\| new Coro \&pool_handler;
533		561
534	$coro->{_invoke} = $cb;	562	$coro->{_invoke} = $cb;
535	$coro->ready;	563	$coro->ready;
536	cede; # for short-lived callbacks, this reduces pressure on the coro pool	564	cede; # for short-lived callbacks, this reduces pressure on the coro pool
537	}	565	}
538	schedule; # sleep well	566	schedule; # sleep well
539	}	567	}
540	};	568	};
		569	$unblock_scheduler->desc ("[unblock_sub scheduler]");
541		570
542	sub unblock_sub(&) {	571	sub unblock_sub(&) {
543	my $cb = shift;	572	my $cb = shift;
544		573
545	sub {	574	sub {
…		…
558		587
559	- you must make very sure that no coro is still active on global	588	- you must make very sure that no coro is still active on global
560	destruction. very bad things might happen otherwise (usually segfaults).	589	destruction. very bad things might happen otherwise (usually segfaults).
561		590
562	- this module is not thread-safe. You should only ever use this module	591	- this module is not thread-safe. You should only ever use this module
563	from the same thread (this requirement might be losened in the future	592	from the same thread (this requirement might be loosened in the future
564	to allow per-thread schedulers, but Coro::State does not yet allow	593	to allow per-thread schedulers, but Coro::State does not yet allow
565	this).	594	this).
566		595
567	=head1 SEE ALSO	596	=head1 SEE ALSO
568		597

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Comparing Coro/Coro.pm (file contents): Revision 1.107 by root, Fri Jan 5 18:25:51 2007 UTC vs. Revision 1.145 by root, Wed Oct 3 16:03:17 2007 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.107 by root, Fri Jan 5 18:25:51 2007 UTC vs.
Revision 1.145 by root, Wed Oct 3 16:03:17 2007 UTC