spin_is_locked always returns 0 on non-SMP systems, which causes btrfs to fail the mount. There is documentation pending as to why checking for spin_is_locked is a bad idea:
https://lkml.org/lkml/2012/3/27/413 The suggested lockdep_assert_held() is not appropriate in this case, as what get_restripe_target() is checking for is that either volume_mutex is held or balance_lock is held. Luckily lockdep_assert_held() is a simple macro: WARN_ON(debug_locks && !lockdep_is_held(l)) We can mimic the structure in get_restripe_target(), but we need to make sure lockdep_is_held() is defined for the !LOCKDEP case. CC: Ilya Dryomov <idryo...@gmail.com> CC: Chris Mason <chris.ma...@oracle.com> CC: Andi Kleen <a...@linux.intel.com> CC: Jeff Mahoney <je...@suse.de> CC: Ingo Molnar <mi...@redhat.com> CC: linux-ker...@vger.kernel.org Signed-off-by: Bobby Powers <bobbypow...@gmail.com> --- fs/btrfs/extent-tree.c | 5 +++-- include/linux/lockdep.h | 1 + 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index a844204..4d13eb1 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -24,6 +24,7 @@ #include <linux/kthread.h> #include <linux/slab.h> #include <linux/ratelimit.h> +#include <linux/lockdep.h> #include "compat.h" #include "hash.h" #include "ctree.h" @@ -3158,8 +3159,8 @@ static u64 get_restripe_target(struct btrfs_fs_info *fs_info, u64 flags) struct btrfs_balance_control *bctl = fs_info->balance_ctl; u64 target = 0; - BUG_ON(!mutex_is_locked(&fs_info->volume_mutex) && - !spin_is_locked(&fs_info->balance_lock)); + BUG_ON(debug_locks && !lockdep_is_held(&fs_info->volume_mutex) && + !lockdep_is_held(&fs_info->balance_lock)); if (!bctl) return 0; diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index d36619e..94c0edb 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -392,6 +392,7 @@ struct lock_class_key { }; #define lockdep_depth(tsk) (0) +#define lockdep_is_held(l) (0) #define lockdep_assert_held(l) do { } while (0) #define lockdep_recursing(tsk) (0) -- 1.7.10.rc3.3.g19a6c -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
