… | |
… | |
14 | |
14 | |
15 | sub some_func : Coro { |
15 | sub some_func : Coro { |
16 | # some more async code |
16 | # some more async code |
17 | } |
17 | } |
18 | |
18 | |
19 | yield; |
19 | cede; |
20 | |
20 | |
21 | =head1 DESCRIPTION |
21 | =head1 DESCRIPTION |
22 | |
22 | |
23 | This module collection manages coroutines. Coroutines are similar to |
23 | This module collection manages coroutines. Coroutines are similar to |
24 | Threads but don't run in parallel. |
24 | threads but don't run in parallel. |
25 | |
25 | |
26 | This module is still experimental, see the BUGS section below. |
26 | In this module, coroutines are defined as "callchain + lexical variables |
|
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27 | + @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own |
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28 | callchain, it's own set of lexicals and it's own set of perl's most |
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29 | important global variables. |
27 | |
30 | |
28 | =cut |
31 | =cut |
29 | |
32 | |
30 | package Coro; |
33 | package Coro; |
31 | |
34 | |
|
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35 | use strict; |
|
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36 | no warnings "uninitialized"; |
|
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37 | |
32 | use Coro::State; |
38 | use Coro::State; |
33 | |
39 | |
34 | use base Exporter; |
40 | use base Exporter::; |
35 | |
41 | |
|
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42 | our $idle; # idle coroutine |
|
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43 | our $main; # main coroutine |
|
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44 | our $current; # current coroutine |
|
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45 | |
36 | $VERSION = 0.05; |
46 | our $VERSION = '2.5'; |
37 | |
47 | |
38 | @EXPORT = qw(async yield schedule terminate); |
48 | our @EXPORT = qw(async cede schedule terminate current); |
39 | @EXPORT_OK = qw($current); |
49 | our %EXPORT_TAGS = ( |
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50 | prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)], |
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51 | ); |
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52 | our @EXPORT_OK = @{$EXPORT_TAGS{prio}}; |
40 | |
53 | |
41 | { |
54 | { |
42 | use subs 'async'; |
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43 | |
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44 | my @async; |
55 | my @async; |
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56 | my $init; |
45 | |
57 | |
46 | # this way of handling attributes simply is NOT scalable ;() |
58 | # this way of handling attributes simply is NOT scalable ;() |
47 | sub import { |
59 | sub import { |
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60 | no strict 'refs'; |
|
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61 | |
48 | Coro->export_to_level(1, @_); |
62 | Coro->export_to_level(1, @_); |
|
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63 | |
49 | my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; |
64 | my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; |
50 | *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub { |
65 | *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub { |
51 | my ($package, $ref) = (shift, shift); |
66 | my ($package, $ref) = (shift, shift); |
52 | my @attrs; |
67 | my @attrs; |
53 | for (@_) { |
68 | for (@_) { |
54 | if ($_ eq "Coro") { |
69 | if ($_ eq "Coro") { |
55 | push @async, $ref; |
70 | push @async, $ref; |
|
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71 | unless ($init++) { |
|
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72 | eval q{ |
|
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73 | sub INIT { |
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74 | &async(pop @async) while @async; |
|
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75 | } |
|
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76 | }; |
|
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77 | } |
56 | } else { |
78 | } else { |
57 | push @attrs, @_; |
79 | push @attrs, $_; |
58 | } |
80 | } |
59 | } |
81 | } |
60 | return $old ? $old->($package, $name, @attrs) : @attrs; |
82 | return $old ? $old->($package, $ref, @attrs) : @attrs; |
61 | }; |
83 | }; |
62 | } |
84 | } |
63 | |
85 | |
64 | sub INIT { |
|
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65 | async pop @async while @async; |
|
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66 | } |
|
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67 | } |
86 | } |
|
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87 | |
|
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88 | =over 4 |
68 | |
89 | |
69 | =item $main |
90 | =item $main |
70 | |
91 | |
71 | This coroutine represents the main program. |
92 | This coroutine represents the main program. |
72 | |
93 | |
73 | =cut |
94 | =cut |
74 | |
95 | |
75 | our $main = new Coro; |
96 | $main = new Coro; |
76 | |
97 | |
77 | =item $current |
98 | =item $current (or as function: current) |
78 | |
99 | |
79 | The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). |
100 | The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). |
80 | |
101 | |
81 | =cut |
102 | =cut |
82 | |
103 | |
83 | # maybe some other module used Coro::Specific before... |
104 | # maybe some other module used Coro::Specific before... |
84 | if ($current) { |
105 | if ($current) { |
85 | $main->{specific} = $current->{specific}; |
106 | $main->{specific} = $current->{specific}; |
86 | } |
107 | } |
87 | |
108 | |
88 | our $current = $main; |
109 | $current = $main; |
|
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110 | |
|
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111 | sub current() { $current } |
89 | |
112 | |
90 | =item $idle |
113 | =item $idle |
91 | |
114 | |
92 | The coroutine to switch to when no other coroutine is running. The default |
115 | The coroutine to switch to when no other coroutine is running. The default |
93 | implementation prints "FATAL: deadlock detected" and exits. |
116 | implementation prints "FATAL: deadlock detected" and exits. |
94 | |
117 | |
95 | =cut |
118 | =cut |
96 | |
119 | |
97 | # should be done using priorities :( |
120 | # should be done using priorities :( |
98 | our $idle = new Coro sub { |
121 | $idle = new Coro sub { |
99 | print STDERR "FATAL: deadlock detected\n"; |
122 | print STDERR "FATAL: deadlock detected\n"; |
100 | exit(51); |
123 | exit(51); |
101 | }; |
124 | }; |
102 | |
125 | |
103 | # we really need priorities... |
126 | # this coroutine is necessary because a coroutine |
104 | ## my @ready; #d# |
127 | # cannot destroy itself. |
105 | our @ready = (); # the ready queue. hehe, rather broken ;) |
128 | my @destroy; |
|
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129 | my $manager; |
|
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130 | $manager = new Coro sub { |
|
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131 | while () { |
|
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132 | # by overwriting the state object with the manager we destroy it |
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133 | # while still being able to schedule this coroutine (in case it has |
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134 | # been readied multiple times. this is harmless since the manager |
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135 | # can be called as many times as neccessary and will always |
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136 | # remove itself from the runqueue |
|
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137 | while (@destroy) { |
|
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138 | my $coro = pop @destroy; |
|
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139 | $coro->{status} ||= []; |
|
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140 | $_->ready for @{delete $coro->{join} || []}; |
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141 | |
|
|
142 | # the next line destroys the _coro_state, but keeps the |
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143 | # process itself intact (we basically make it a zombie |
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144 | # process that always runs the manager thread, so it's possible |
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145 | # to transfer() to this process). |
|
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146 | $coro->{_coro_state} = $manager->{_coro_state}; |
|
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147 | } |
|
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148 | &schedule; |
|
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149 | } |
|
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150 | }; |
106 | |
151 | |
107 | # static methods. not really. |
152 | # static methods. not really. |
|
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153 | |
|
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154 | =back |
108 | |
155 | |
109 | =head2 STATIC METHODS |
156 | =head2 STATIC METHODS |
110 | |
157 | |
111 | Static methods are actually functions that operate on the current process only. |
158 | Static methods are actually functions that operate on the current process only. |
112 | |
159 | |
… | |
… | |
115 | =item async { ... } [@args...] |
162 | =item async { ... } [@args...] |
116 | |
163 | |
117 | Create a new asynchronous process and return it's process object |
164 | Create a new asynchronous process and return it's process object |
118 | (usually unused). When the sub returns the new process is automatically |
165 | (usually unused). When the sub returns the new process is automatically |
119 | terminated. |
166 | terminated. |
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167 | |
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168 | When the coroutine dies, the program will exit, just as in the main |
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169 | program. |
120 | |
170 | |
121 | # create a new coroutine that just prints its arguments |
171 | # create a new coroutine that just prints its arguments |
122 | async { |
172 | async { |
123 | print "@_\n"; |
173 | print "@_\n"; |
124 | } 1,2,3,4; |
174 | } 1,2,3,4; |
125 | |
175 | |
126 | The coderef you submit MUST NOT be a closure that refers to variables |
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127 | in an outer scope. This does NOT work. Pass arguments into it instead. |
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128 | |
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129 | =cut |
176 | =cut |
130 | |
177 | |
131 | sub async(&@) { |
178 | sub async(&@) { |
132 | my $pid = new Coro @_; |
179 | my $pid = new Coro @_; |
|
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180 | $manager->ready; # this ensures that the stack is cloned from the manager |
133 | $pid->ready; |
181 | $pid->ready; |
134 | $pid; |
182 | $pid; |
135 | } |
183 | } |
136 | |
184 | |
137 | =item schedule |
185 | =item schedule |
… | |
… | |
140 | into the ready queue, so calling this function usually means you will |
188 | into the ready queue, so calling this function usually means you will |
141 | never be called again. |
189 | never be called again. |
142 | |
190 | |
143 | =cut |
191 | =cut |
144 | |
192 | |
145 | my $prev; |
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146 | |
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147 | sub schedule { |
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148 | # should be done using priorities :( |
|
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149 | ($prev, $current) = ($current, shift @ready || $idle); |
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150 | Coro::State::transfer($prev, $current); |
|
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151 | } |
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152 | |
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153 | =item yield |
193 | =item cede |
154 | |
194 | |
155 | Yield to other processes. This function puts the current process into the |
195 | "Cede" to other processes. This function puts the current process into the |
156 | ready queue and calls C<schedule>. |
196 | ready queue and calls C<schedule>, which has the effect of giving up the |
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197 | current "timeslice" to other coroutines of the same or higher priority. |
157 | |
198 | |
158 | =cut |
199 | =cut |
159 | |
200 | |
160 | sub yield { |
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161 | $current->ready; |
|
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162 | &schedule; |
|
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163 | } |
|
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164 | |
|
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165 | =item terminate |
201 | =item terminate [arg...] |
166 | |
202 | |
167 | Terminates the current process. |
203 | Terminates the current process with the given status values (see L<cancel>). |
168 | |
|
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169 | Future versions of this function will allow result arguments. |
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170 | |
204 | |
171 | =cut |
205 | =cut |
172 | |
206 | |
173 | sub terminate { |
207 | sub terminate { |
174 | $current->{_results} = [@_]; |
208 | $current->cancel (@_); |
175 | &schedule; |
|
|
176 | } |
209 | } |
177 | |
210 | |
178 | =back |
211 | =back |
179 | |
212 | |
180 | # dynamic methods |
213 | # dynamic methods |
… | |
… | |
186 | =over 4 |
219 | =over 4 |
187 | |
220 | |
188 | =item new Coro \&sub [, @args...] |
221 | =item new Coro \&sub [, @args...] |
189 | |
222 | |
190 | Create a new process and return it. When the sub returns the process |
223 | Create a new process and return it. When the sub returns the process |
191 | automatically terminates. To start the process you must first put it into |
224 | automatically terminates as if C<terminate> with the returned values were |
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225 | called. To make the process run you must first put it into the ready queue |
192 | the ready queue by calling the ready method. |
226 | by calling the ready method. |
193 | |
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194 | The coderef you submit MUST NOT be a closure that refers to variables |
|
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195 | in an outer scope. This does NOT work. Pass arguments into it instead. |
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196 | |
227 | |
197 | =cut |
228 | =cut |
198 | |
229 | |
199 | sub _newcoro { |
230 | sub _newcoro { |
200 | terminate &{+shift}; |
231 | terminate &{+shift}; |
… | |
… | |
207 | }, $class; |
238 | }, $class; |
208 | } |
239 | } |
209 | |
240 | |
210 | =item $process->ready |
241 | =item $process->ready |
211 | |
242 | |
212 | Put the current process into the ready queue. |
243 | Put the given process into the ready queue. |
213 | |
244 | |
214 | =cut |
245 | =cut |
215 | |
246 | |
216 | sub ready { |
247 | =item $process->cancel (arg...) |
217 | push @ready, $_[0]; |
248 | |
|
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249 | Terminates the given process and makes it return the given arguments as |
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250 | status (default: the empty list). |
|
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251 | |
|
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252 | =cut |
|
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253 | |
|
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254 | sub cancel { |
|
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255 | my $self = shift; |
|
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256 | $self->{status} = [@_]; |
|
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257 | push @destroy, $self; |
|
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258 | $manager->ready; |
|
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259 | &schedule if $current == $self; |
|
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260 | } |
|
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261 | |
|
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262 | =item $process->join |
|
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263 | |
|
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264 | Wait until the coroutine terminates and return any values given to the |
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265 | C<terminate> or C<cancel> functions. C<join> can be called multiple times |
|
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266 | from multiple processes. |
|
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267 | |
|
|
268 | =cut |
|
|
269 | |
|
|
270 | sub join { |
|
|
271 | my $self = shift; |
|
|
272 | unless ($self->{status}) { |
|
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273 | push @{$self->{join}}, $current; |
|
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274 | &schedule; |
|
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275 | } |
|
|
276 | wantarray ? @{$self->{status}} : $self->{status}[0]; |
|
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277 | } |
|
|
278 | |
|
|
279 | =item $oldprio = $process->prio($newprio) |
|
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280 | |
|
|
281 | Sets (or gets, if the argument is missing) the priority of the |
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282 | process. Higher priority processes get run before lower priority |
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283 | processes. Priorities are small signed integers (currently -4 .. +3), |
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284 | that you can refer to using PRIO_xxx constants (use the import tag :prio |
|
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285 | to get then): |
|
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286 | |
|
|
287 | PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN |
|
|
288 | 3 > 1 > 0 > -1 > -3 > -4 |
|
|
289 | |
|
|
290 | # set priority to HIGH |
|
|
291 | current->prio(PRIO_HIGH); |
|
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292 | |
|
|
293 | The idle coroutine ($Coro::idle) always has a lower priority than any |
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294 | existing coroutine. |
|
|
295 | |
|
|
296 | Changing the priority of the current process will take effect immediately, |
|
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297 | but changing the priority of processes in the ready queue (but not |
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298 | running) will only take effect after the next schedule (of that |
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299 | process). This is a bug that will be fixed in some future version. |
|
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300 | |
|
|
301 | =cut |
|
|
302 | |
|
|
303 | sub prio { |
|
|
304 | my $old = $_[0]{prio}; |
|
|
305 | $_[0]{prio} = $_[1] if @_ > 1; |
|
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306 | $old; |
|
|
307 | } |
|
|
308 | |
|
|
309 | =item $newprio = $process->nice($change) |
|
|
310 | |
|
|
311 | Similar to C<prio>, but subtract the given value from the priority (i.e. |
|
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312 | higher values mean lower priority, just as in unix). |
|
|
313 | |
|
|
314 | =cut |
|
|
315 | |
|
|
316 | sub nice { |
|
|
317 | $_[0]{prio} -= $_[1]; |
|
|
318 | } |
|
|
319 | |
|
|
320 | =item $olddesc = $process->desc($newdesc) |
|
|
321 | |
|
|
322 | Sets (or gets in case the argument is missing) the description for this |
|
|
323 | process. This is just a free-form string you can associate with a process. |
|
|
324 | |
|
|
325 | =cut |
|
|
326 | |
|
|
327 | sub desc { |
|
|
328 | my $old = $_[0]{desc}; |
|
|
329 | $_[0]{desc} = $_[1] if @_ > 1; |
|
|
330 | $old; |
218 | } |
331 | } |
219 | |
332 | |
220 | =back |
333 | =back |
221 | |
334 | |
222 | =cut |
335 | =cut |
223 | |
336 | |
224 | 1; |
337 | 1; |
225 | |
338 | |
226 | =head1 BUGS |
339 | =head1 BUGS/LIMITATIONS |
227 | |
340 | |
228 | - could be faster, especially when the core would introduce special |
341 | - you must make very sure that no coro is still active on global |
229 | support for coroutines (like it does for threads). |
342 | destruction. very bad things might happen otherwise (usually segfaults). |
230 | - there is still a memleak on coroutine termination that I could not |
343 | |
231 | identify. Could be as small as a single SV. |
344 | - this module is not thread-safe. You should only ever use this module |
232 | - this module is not well-tested. |
345 | from the same thread (this requirement might be losened in the future |
|
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346 | to allow per-thread schedulers, but Coro::State does not yet allow |
|
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347 | this). |
233 | |
348 | |
234 | =head1 SEE ALSO |
349 | =head1 SEE ALSO |
235 | |
350 | |
236 | L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, |
351 | Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>. |
237 | L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. |
352 | |
|
|
353 | Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>. |
|
|
354 | |
|
|
355 | Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>. |
|
|
356 | |
|
|
357 | Embedding: L<Coro:MakeMaker> |
238 | |
358 | |
239 | =head1 AUTHOR |
359 | =head1 AUTHOR |
240 | |
360 | |
241 | Marc Lehmann <pcg@goof.com> |
361 | Marc Lehmann <schmorp@schmorp.de> |
242 | http://www.goof.com/pcg/marc/ |
362 | http://home.schmorp.de/ |
243 | |
363 | |
244 | =cut |
364 | =cut |
245 | |
365 | |