lglock: Update lockdep annotations to report recursive local locks

Oleg Nesterov recently noticed that the lockdep annotations in lglock.c
are not sufficient to detect some obvious deadlocks, such as
lg_local_lock(LOCK) + lg_local_lock(LOCK) or spin_lock(X) +
lg_local_lock(Y) vs lg_local_lock(Y) + spin_lock(X).

Both issues are easily fixed by indicating to lockdep that lglock's local
locks are not recursive.  We shouldn't use the rwlock acquire/release
functions here, as lglock doesn't share the same semantics.  Instead we
can base our lockdep annotations on the lock_acquire_shared (for local
lglock) and lock_acquire_exclusive (for global lglock) helpers.

I am not proposing new lglock specific helpers as I don't see the point of
the existing second level of helpers :)

Noticed-by: Oleg Nesterov <[email protected]>
Signed-off-by: Michel Lespinasse <[email protected]>
Cc: Lai Jiangshan <[email protected]>
Cc: "Srivatsa S. Bhat" <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: "Paul E. McKenney" <[email protected]>
Cc: Steven Rostedt <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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