- For kernel compiled only with KDTRACE_HOOKS and not any lock debugging

  option, unbreak the lock tracing release semantic by embedding
  calls to LOCKSTAT_PROFILE_RELEASE_LOCK() direclty in the inlined
  version of the releasing functions for mutex, rwlock and sxlock.
  Failing to do so skips the lockstat_probe_func invokation for
  unlocking.
- As part of the LOCKSTAT support is inlined in mutex operation, for
  kernel compiled without lock debugging options, potentially every
  consumer must be compiled including opt_kdtrace.h.
  Fix this by moving KDTRACE_HOOKS into opt_global.h and remove the
  dependency by opt_kdtrace.h for all files, as now only KDTRACE_FRAMES
  is linked there and it is only used as a compile-time stub [0].

[0] immediately shows some new bug as DTRACE-derived support for debug
in sfxge is broken and it was never really tested.  As it was not
including correctly opt_kdtrace.h before it was never enabled so it
was kept broken for a while.  Fix this by using a protection stub,
leaving sfxge driver authors the responsibility for fixing it
appropriately [1].

Sponsored by:	EMC / Isilon storage division
Discussed with:	rstone
[0] Reported by:	rstone
[1] Discussed with:	philip

1 files changed, 3 insertions, 0 deletions

diff --git a/sys/sys/mutex.h b/sys/sys/mutex.h
index 1c9d5d5..39d8f45 100644
--- a/sys/sys/mutex.h
+++ b/sys/sys/mutex.h
@@ -229,6 +229,9 @@ void	thread_lock_flags_(struct thread *, int, const char *, int);
 #define __mtx_unlock(mp, tid, opts, file, line) do {			\
 	uintptr_t _tid = (uintptr_t)(tid);				\
 									\
+	if ((mp)->mtx_recurse == 0)					\
+		 LOCKSTAT_PROFILE_RELEASE_LOCK(LS_MTX_UNLOCK_RELEASE,	\
+		    (mp));						\
 	if (!_mtx_release_lock((mp), _tid))				\
 		_mtx_unlock_sleep((mp), (opts), (file), (line));	\
 } while (0)