validation/sm_locking3.c

   1 int _spin_trylock(int name);
   2 void _spin_lock(int name);
   3 void _spin_unlock(int name);
   4
   5 int func (void)
   6 {
   7         int mylock = 1;
   8
   9         if (!({frob(); frob(); _spin_trylock(mylock);}))
  10                 return;
  11
  12         frob();
  13         _spin_unlock(mylock);
  14
  15         if (((_spin_trylock(mylock)?1:0)?1:0))
  16                 return;
  17         frob_somemore();
  18         _spin_unlock(mylock);
  19
  20         return;
  21 }
  22 /*
  23  * check-name: Smatch locking #3
  24  * check-command: smatch --project=kernel -DCONFIG_SMP=y sm_locking3.c
  25  *
  26  * check-output-start
  27 sm_locking3.c:18 func() error: double unlocked 'mylock' (orig line 13)
  28 sm_locking3.c:20 func() warn: inconsistent returns 'mylock'.
  29   Locked on  : 16
  30   Unlocked on: 20
  31  * check-output-end
  32  */