lib/kernel/time/timer.cc

   1 // lib/kernel/time/timer.cc -- Generic timer multiplexing
   2 //
   3 // This software is copyright (c) 2006 Scott Wood <scott@buserror.net>.
   4 //
   5 // Permission is hereby granted, free of charge, to any person obtaining a copy of
   6 // this software and associated documentation files (the "Software"), to deal with
   7 // the Software without restriction, including without limitation the rights to
   8 // use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
   9 // of the Software, and to permit persons to whom the Software is furnished to do
  10 // so, subject to the following conditions:
  11 //
  12 //     * Redistributions of source code must retain the above copyright notice,
  13 //       this list of conditions and the following disclaimers.
  14 //
  15 //     * Redistributions in binary form must reproduce the above copyright notice,
  16 //       this list of conditions and the following disclaimers in the
  17 //       documentation and/or other materials provided with the distribution.
  18 //
  19 //     * The names of the Software's authors and/or contributors
  20 //       may not be used to endorse or promote products derived from
  21 //       this Software without specific prior written permission.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  24 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
  25 // FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
  26 // CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  27 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  28 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS WITH THE
  29 // SOFTWARE.
  30
  31 #include <kernel/time.h>
  32 #include <lowlevel/clock.h>
  33
  34 namespace Time {
  35         void TimerMux::arm(TimerEntry *entry, Time expiry)
  36         {
  37                 AutoSpinLockRecIRQ autolock(lock);
  38
  39                 bool was_empty = heap.empty();
  40                 Time oldexpiry;
  41
  42                 if (!was_empty) {
  43                         oldexpiry = heap.get_top()->expiry;
  44                 } else {
  45                         // Shut up the compiler
  46                         oldexpiry.seconds = 0;
  47                         oldexpiry.nanos = 0;
  48                 }
  49
  50                 entry->expiry = expiry;
  51
  52                 if (entry->is_armed())
  53                         heap.requeue(entry);
  54                 else
  55                         heap.add(entry);
  56
  57                 Time newexpiry = heap.get_top()->expiry;
  58                 if (was_empty || oldexpiry != newexpiry)
  59                         parent.arm(newexpiry);
  60         }
  61
  62         void TimerMux::disarm(TimerEntry *entry)
  63         {
  64                 AutoSpinLockRecIRQ autolock(lock);
  65
  66                 if (entry->is_armed()) {
  67                         bool was_top = entry == heap.get_top();
  68
  69                         heap.del(entry);
  70
  71                         if (was_top)
  72                                 parent.arm(heap.get_top()->expiry);
  73                 }
  74         }
  75
  76         void TimerMux::run()
  77         {
  78                 DroppableAutoSpinLockRecIRQ autolock(lock);
  79
  80                 while (true) {
  81                         TimerEntry *top = heap.get_top();
  82                         Time now;
  83                         clock.get_time(&now);
  84
  85                         if (now < top->expiry)
  86                                 break;
  87
  88                         heap.del(top);
  89
  90                         autolock.unlock();
  91                         top->action();
  92                         autolock.lock();
  93                 }
  94
  95                 if (!heap.empty())
  96                         parent.arm(heap.get_top()->expiry);
  97         }
  98
  99         void TimerEntry::set_action(System::Events::Event *event)
 100         {
 101                 // FIXME
 102         }
 103
 104         void TimerEntry::action()
 105         {
 106                 // FIXME
 107         }
 108 }
 109
 110 #include _KERNEL_SERVER(time/timer/footer.cc)