Introduce macro stubs in the mutex implementation that will be always

defined and will allow consumers, willing to provide options, file and
line to locking requests, to not worry about options redefining the
interfaces.
This is typically useful when there is the need to build another
locking interface on top of the mutex one.

The introduced functions that consumers can use are:
- mtx_lock_flags_
- mtx_unlock_flags_
- mtx_lock_spin_flags_
- mtx_unlock_spin_flags_
- mtx_assert_
- thread_lock_flags_

Spare notes:
- Likely we can get rid of all the 'INVARIANTS' specification in the
  ppbus code by using the same macro as done in this patch (but this is
  left to the ppbus maintainer)
- all the other locking interfaces may require a similar cleanup, where
  the most notable case is sx which will allow a further cleanup of
  vm_map locking facilities
- The patch should be fully compatible with older branches, thus a MFC
  is previewed (infact it uses all the underlying mechanisms already
  present).

Comments review by:	eadler, Ben Kaduk
Discussed with:		kib, jhb
MFC after:	1 month

1 files changed, 1 insertions, 4 deletions

diff --git a/sys/dev/ppbus/ppb_base.c b/sys/dev/ppbus/ppb_base.c
index 30c42a4..62769b0 100644
--- a/sys/dev/ppbus/ppb_base.c
+++ b/sys/dev/ppbus/ppb_base.c
@@ -236,11 +236,8 @@ ppb_unlock(device_t bus)
 void
 _ppb_assert_locked(device_t bus, const char *file, int line)
 {
-#ifdef INVARIANTS
-	struct ppb_data *ppb = DEVTOSOFTC(bus);
 
-	_mtx_assert(ppb->ppc_lock, MA_OWNED, file, line);
-#endif
+	mtx_assert_(DEVTOSOFTC(bus)->ppc_lock, MA_OWNED, file, line);
 }
 
 void