Commit 95989c46 authored Jun 08, 2017 by Brian Foster Committed by Darrick J. Wong Jun 08, 2017

xfs: fix spurious spin_is_locked() assert failures on non-smp kernels



The 0-day kernel test robot reports assertion failures on
!CONFIG_SMP kernels due to failed spin_is_locked() checks. As it
turns out, spin_is_locked() is hardcoded to return zero on
!CONFIG_SMP kernels and so this function cannot be relied on to
verify spinlock state in this configuration.

To avoid this problem, replace the associated asserts with lockdep
variants that do the right thing regardless of kernel configuration.
Drop the one assert that checks for an unlocked lock as there is no
suitable lockdep variant for that case. This moves the spinlock
checks from XFS debug code to lockdep, but generally provides the
same level of protection.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

parent 63db7c81

fs/xfs/xfs_buf.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -117,7 +117,7 @@ static inline void
		__xfs_buf_ioacct_dec(
		struct xfs_buf *bp)
		{
		ASSERT(spin_is_locked(&bp->b_lock));
		lockdep_assert_held(&bp->b_lock);

		if (bp->b_state & XFS_BSTATE_IN_FLIGHT) {
		bp->b_state &= ~XFS_BSTATE_IN_FLIGHT;

fs/xfs/xfs_icache.c

+2 −3

Original line number	Diff line number	Diff line
		@@ -66,7 +66,6 @@ xfs_inode_alloc(

		XFS_STATS_INC(mp, vn_active);
		ASSERT(atomic_read(&ip->i_pincount) == 0);
		ASSERT(!spin_is_locked(&ip->i_flags_lock));
		ASSERT(!xfs_isiflocked(ip));
		ASSERT(ip->i_ino == 0);

		@@ -190,7 +189,7 @@ xfs_perag_set_reclaim_tag(
		{
		struct xfs_mount *mp = pag->pag_mount;

		ASSERT(spin_is_locked(&pag->pag_ici_lock));
		lockdep_assert_held(&pag->pag_ici_lock);
		if (pag->pag_ici_reclaimable++)
		return;

		@@ -212,7 +211,7 @@ xfs_perag_clear_reclaim_tag(
		{
		struct xfs_mount *mp = pag->pag_mount;

		ASSERT(spin_is_locked(&pag->pag_ici_lock));
		lockdep_assert_held(&pag->pag_ici_lock);
		if (--pag->pag_ici_reclaimable)
		return;

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