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 condition:
  11 //
  12 // The above copyright notice and this permission notice shall be
  13 // included in all copies or substantial portions of the Software.
  14 //
  15 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
  17 // FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
  18 // CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS WITH THE
  21 // SOFTWARE.
  22
  23 #include <kernel/time.h>
  24 #include <lowlevel/clock.h>
  25
  26 namespace Time {
  27         void TimerMux::arm(TimerEntry *entry, Time expiry)
  28         {
  29                 AutoSpinLockRecIRQ autolock(lock);
  30
  31                 bool was_empty = heap.empty();
  32                 Time oldexpiry;
  33
  34                 if (!was_empty) {
  35                         oldexpiry = heap.get_top()->expiry;
  36                 } else {
  37                         // Shut up the compiler
  38                         oldexpiry.seconds = 0;
  39                         oldexpiry.nanos = 0;
  40                 }
  41
  42                 entry->expiry = expiry;
  43
  44                 if (entry->is_armed())
  45                         heap.requeue(entry);
  46                 else
  47                         heap.add(entry);
  48
  49                 Time newexpiry = heap.get_top()->expiry;
  50                 if (was_empty || oldexpiry != newexpiry)
  51                         parent.arm(newexpiry);
  52         }
  53
  54         void TimerMux::disarm(TimerEntry *entry)
  55         {
  56                 AutoSpinLockRecIRQ autolock(lock);
  57
  58                 if (entry->is_armed()) {
  59                         bool was_top = entry == heap.get_top();
  60
  61                         heap.del(entry);
  62
  63                         if (was_top)
  64                                 parent.arm(heap.get_top()->expiry);
  65                 }
  66         }
  67
  68         void TimerMux::run()
  69         {
  70                 DroppableAutoSpinLockRecIRQ autolock(lock);
  71
  72                 while (true) {
  73                         TimerEntry *top = heap.get_top();
  74                         Time now;
  75                         clock.get_time(&now);
  76
  77                         if (now < top->expiry)
  78                                 break;
  79
  80                         heap.del(top);
  81
  82                         autolock.unlock();
  83                         top->action();
  84                         autolock.lock();
  85                 }
  86
  87                 if (!heap.empty())
  88                         parent.arm(heap.get_top()->expiry);
  89         }
  90
  91         void TimerEntry::set_action(System::Events::Event *event)
  92         {
  93                 // FIXME
  94         }
  95
  96         void TimerEntry::action()
  97         {
  98                 // FIXME
  99         }
 100 }
 101
 102 #include _KERNEL_SERVER(time/timer/footer.cc)