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 can be fixed by indicating to lockdep that lglock's local locks are not recursive. Patch 1 introduces helper macros for lockdep annotations. Patch 2 makes sure to use the appropriate helper macros to indicate that the lglock local lock is a shared, non-recursive lock. Michel Lespinasse (2): lockdep: introduce lock_acquire_exclusive/shared helper macros lglock: update lockdep annotations to report recursive local locks include/linux/lockdep.h | 92 +++++++++++++------------------------------------ kernel/lglock.c | 12 +++---- 2 files changed, 29 insertions(+), 75 deletions(-) -- 1.8.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
