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

Comparing Coro/Coro.pm (file contents):
Revision 1.102 by root, Fri Dec 29 11:37:49 2006 UTC vs.
Revision 1.107 by root, Fri Jan 5 18:25:51 2007 UTC

…		…
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 $VERSION = '3.3';
56		56
57	our @EXPORT = qw(async cede schedule terminate current unblock_sub);	57	our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub);
58	our %EXPORT_TAGS = (	58	our %EXPORT_TAGS = (
59	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],	59	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
60	);	60	);
61	our @EXPORT_OK = (@{$EXPORT_TAGS{prio}}, qw(nready));	61	our @EXPORT_OK = (@{$EXPORT_TAGS{prio}}, qw(nready));
62		62
…		…
141	$idle = sub {	141	$idle = sub {
142	require Carp;	142	require Carp;
143	Carp::croak ("FATAL: deadlock detected");	143	Carp::croak ("FATAL: deadlock detected");
144	};	144	};
145		145
		146	sub _cancel {
		147	my ($self) = @_;
		148
		149	# free coroutine data and mark as destructed
		150	$self->_destroy
		151	or return;
		152
		153	# call all destruction callbacks
		154	$_->(@{$self->{status}})
		155	for @{(delete $self->{destroy_cb}) \|\| []};
		156	}
		157
146	# this coroutine is necessary because a coroutine	158	# this coroutine is necessary because a coroutine
147	# cannot destroy itself.	159	# cannot destroy itself.
148	my @destroy;	160	my @destroy;
		161	my $manager;
		162
149	my $manager; $manager = new Coro sub {	163	$manager = new Coro sub {
150	while () {	164	while () {
151	# by overwriting the state object with the manager we destroy it	165	(shift @destroy)->_cancel
152	# while still being able to schedule this coroutine (in case it has
153	# been readied multiple times. this is harmless since the manager
154	# can be called as many times as neccessary and will always
155	# remove itself from the runqueue
156	while (@destroy) {	166	while @destroy;
157	my $coro = pop @destroy;
158		167
159	$coro->{status} \|\|= [];
160
161	$_->ready for @{(delete $coro->{join} ) \|\| []};
162	$_->(@{$coro->{status}}) for @{(delete $coro->{destroy_cb}) \|\| []};
163
164	# the next line destroys the coro state, but keeps the
165	# coroutine itself intact (we basically make it a zombie
166	# coroutine that always runs the manager thread, so it's possible
167	# to transfer() to this coroutine).
168	$coro->_clone_state_from ($manager);
169	}
170	&schedule;	168	&schedule;
171	}	169	}
172	};	170	};
		171
		172	$manager->prio (PRIO_MAX);
173		173
174	# static methods. not really.	174	# static methods. not really.
175		175
176	=back	176	=back
177		177
…		…
198	} 1,2,3,4;	198	} 1,2,3,4;
199		199
200	=cut	200	=cut
201		201
202	sub async(&@) {	202	sub async(&@) {
203	my $pid = new Coro @_;	203	my $coro = new Coro @_;
204	$pid->ready;	204	$coro->ready;
205	$pid	205	$coro
		206	}
		207
		208	=item async_pool { ... } [@args...]
		209
		210	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
		212	that might have executed other code already (which can be good or bad :).
		213
		214	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.
		216
		217	The priority will be reset to C<0> after each job, otherwise the coroutine
		218	will be re-used "as-is".
		219
		220	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
		222	required.
		223
		224	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 {
		226	terminate }> once per second or so to slowly replenish the pool.
		227
		228	=cut
		229
		230	our $POOL_SIZE = 8;
		231	our @pool;
		232
		233	sub pool_handler {
		234	while () {
		235	my ($cb, @arg) = @{ delete $current->{_invoke} };
		236
		237	eval {
		238	$cb->(@arg);
		239	};
		240	warn $@ if $@;
		241
		242	last if @pool >= $POOL_SIZE;
		243	push @pool, $current;
		244
		245	$current->prio (0);
		246	schedule;
		247	}
		248	}
		249
		250	sub async_pool(&@) {
		251	# this is also inlined into the unlock_scheduler
		252	my $coro = (pop @pool or new Coro \&pool_handler);
		253
		254	$coro->{_invoke} = [@_];
		255	$coro->ready;
		256
		257	$coro
206	}	258	}
207		259
208	=item schedule	260	=item schedule
209		261
210	Calls the scheduler. Please note that the current coroutine will not be put	262	Calls the scheduler. Please note that the current coroutine will not be put
…		…
235		287
236	"Cede" to other coroutines. This function puts the current coroutine into the	288	"Cede" to other coroutines. This function puts the current coroutine into the
237	ready queue and calls C<schedule>, which has the effect of giving up the	289	ready queue and calls C<schedule>, which has the effect of giving up the
238	current "timeslice" to other coroutines of the same or higher priority.	290	current "timeslice" to other coroutines of the same or higher priority.
239		291
		292	Returns true if at least one coroutine switch has happened.
		293
240	=item Coro::cede_notself	294	=item Coro::cede_notself
241		295
242	Works like cede, but is not exported by default and will cede to any	296	Works like cede, but is not exported by default and will cede to any
243	coroutine, regardless of priority, once.	297	coroutine, regardless of priority, once.
		298
		299	Returns true if at least one coroutine switch has happened.
244		300
245	=item terminate [arg...]	301	=item terminate [arg...]
246		302
247	Terminates the current coroutine with the given status values (see L<cancel>).	303	Terminates the current coroutine with the given status values (see L<cancel>).
248		304
…		…
294	Return wether the coroutine is currently the ready queue or not,	350	Return wether the coroutine is currently the ready queue or not,
295		351
296	=item $coroutine->cancel (arg...)	352	=item $coroutine->cancel (arg...)
297		353
298	Terminates the given coroutine and makes it return the given arguments as	354	Terminates the given coroutine and makes it return the given arguments as
299	status (default: the empty list).	355	status (default: the empty list). Never returns if the coroutine is the
		356	current coroutine.
300		357
301	=cut	358	=cut
302		359
303	sub cancel {	360	sub cancel {
304	my $self = shift;	361	my $self = shift;
305	$self->{status} = [@_];	362	$self->{status} = [@_];
		363
		364	if ($current == $self) {
306	push @destroy, $self;	365	push @destroy, $self;
307	$manager->ready;	366	$manager->ready;
308	&schedule if $current == $self;	367	&schedule while 1;
		368	} else {
		369	$self->_cancel;
		370	}
309	}	371	}
310		372
311	=item $coroutine->join	373	=item $coroutine->join
312		374
313	Wait until the coroutine terminates and return any values given to the	375	Wait until the coroutine terminates and return any values given to the
…		…
316		378
317	=cut	379	=cut
318		380
319	sub join {	381	sub join {
320	my $self = shift;	382	my $self = shift;
		383
321	unless ($self->{status}) {	384	unless ($self->{status}) {
322	push @{$self->{join}}, $current;	385	my $current = $current;
323	&schedule;	386
		387	push @{$self->{destroy_cb}}, sub {
		388	$current->ready;
		389	undef $current;
		390	};
		391
		392	&schedule while $current;
324	}	393	}
		394
325	wantarray ? @{$self->{status}} : $self->{status}[0];	395	wantarray ? @{$self->{status}} : $self->{status}[0];
326	}	396	}
327		397
328	=item $coroutine->on_destroy (\&cb)	398	=item $coroutine->on_destroy (\&cb)
329		399
…		…
391	i.e. that can be swicthed to. The value C<0> means that the only runnable	461	i.e. that can be swicthed to. The value C<0> means that the only runnable
392	coroutine is the currently running one, so C<cede> would have no effect,	462	coroutine is the currently running one, so C<cede> would have no effect,
393	and C<schedule> would cause a deadlock unless there is an idle handler	463	and C<schedule> would cause a deadlock unless there is an idle handler
394	that wakes up some coroutines.	464	that wakes up some coroutines.
395		465
		466	=item my $guard = Coro::guard { ... }
		467
		468	This creates and returns a guard object. Nothing happens until the objetc
		469	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
		471	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,
		473	C<< ->cancel >>, which will keep the codeblock from being executed.
		474
		475	Example: set some flag and clear it again when the coroutine gets canceled
		476	or the function returns:
		477
		478	sub do_something {
		479	my $guard = Coro::guard { $busy = 0 };
		480	$busy = 1;
		481
		482	# do something that requires $busy to be true
		483	}
		484
		485	=cut
		486
		487	sub guard(&) {
		488	bless \(my $cb = $_[0]), "Coro::guard"
		489	}
		490
		491	sub Coro::guard::cancel {
		492	${$_[0]} = sub { };
		493	}
		494
		495	sub Coro::guard::DESTROY {
		496	${$_[0]}->();
		497	}
		498
		499
396	=item unblock_sub { ... }	500	=item unblock_sub { ... }
397		501
398	This utility function takes a BLOCK or code reference and "unblocks" it,	502	This utility function takes a BLOCK or code reference and "unblocks" it,
399	returning the new coderef. This means that the new coderef will return	503	returning the new coderef. This means that the new coderef will return
400	immediately without blocking, returning nothing, while the original code	504	immediately without blocking, returning nothing, while the original code
…		…
413	In short: simply use C<unblock_sub { ... }> instead of C<sub { ... }> when	517	In short: simply use C<unblock_sub { ... }> instead of C<sub { ... }> when
414	creating event callbacks that want to block.	518	creating event callbacks that want to block.
415		519
416	=cut	520	=cut
417		521
418	our @unblock_pool;
419	our @unblock_queue;	522	our @unblock_queue;
420	our $UNBLOCK_POOL_SIZE = 2;
421		523
422	sub unblock_handler_ {	524	# we create a special coro because we want to cede,
423	while () {	525	# to reduce pressure on the coro pool (because most callbacks
424	my ($cb, @arg) = @{ delete $Coro::current->{arg} };	526	# return immediately and can be reused) and because we cannot cede
425	$cb->(@arg);	527	# inside an event callback.
426
427	last if @unblock_pool >= $UNBLOCK_POOL_SIZE;
428	push @unblock_pool, $Coro::current;
429	schedule;
430	}
431	}
432
433	our $unblock_scheduler = async {	528	our $unblock_scheduler = async {
434	while () {	529	while () {
435	while (my $cb = pop @unblock_queue) {	530	while (my $cb = pop @unblock_queue) {
		531	# this is an inlined copy of async_pool
436	my $handler = (pop @unblock_pool or new Coro \&unblock_handler_);	532	my $coro = (pop @pool or new Coro \&pool_handler);
437	$handler->{arg} = $cb;	533
		534	$coro->{_invoke} = $cb;
438	$handler->ready;	535	$coro->ready;
439	cede;	536	cede; # for short-lived callbacks, this reduces pressure on the coro pool
440	}	537	}
441		538	schedule; # sleep well
442	schedule;
443	}	539	}
444	};	540	};
445		541
446	sub unblock_sub(&) {	542	sub unblock_sub(&) {
447	my $cb = shift;	543	my $cb = shift;
448		544
449	sub {	545	sub {
450	push @unblock_queue, [$cb, @_];	546	unshift @unblock_queue, [$cb, @_];
451	$unblock_scheduler->ready;	547	$unblock_scheduler->ready;
452	}	548	}
453	}	549	}
454		550
455	=back	551	=back

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Comparing Coro/Coro.pm (file contents): Revision 1.102 by root, Fri Dec 29 11:37:49 2006 UTC vs. Revision 1.107 by root, Fri Jan 5 18:25:51 2007 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.102 by root, Fri Dec 29 11:37:49 2006 UTC vs.
Revision 1.107 by root, Fri Jan 5 18:25:51 2007 UTC