49641f1acf
When we release the iclog, we do an atomic_dec_and_lock to determine if we are the last reference and need to trigger update of log headers and writeout. However, in xlog_state_get_iclog_space() we also need to check if we have the last reference count there. If we do, we release the log buffer, otherwise we decrement the reference count. But the compare and decrement in xlog_state_get_iclog_space() is not atomic, so both places can see a reference count of 2 and neither will release the iclog. That leads to a filesystem hang. Close the race by replacing the atomic_read() and atomic_dec() pair with atomic_add_unless() to ensure that they are executed atomically. Signed-off-by: Dave Chinner <david@fromorbit.com> Reviewed-by: Tim Shimmin <tes@sgi.com> Tested-by: Eric Sandeen <sandeen@sandeen.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| linux-2.6 | ||
| quota | ||
| support | ||
| Kconfig | ||
| Makefile | ||
| xfs.h | ||
| xfs_acl.c | ||
| xfs_acl.h | ||
| xfs_ag.h | ||
| xfs_alloc.c | ||
| xfs_alloc.h | ||
| xfs_alloc_btree.c | ||
| xfs_alloc_btree.h | ||
| xfs_arch.h | ||
| xfs_attr.c | ||
| xfs_attr.h | ||
| xfs_attr_leaf.c | ||
| xfs_attr_leaf.h | ||
| xfs_attr_sf.h | ||
| xfs_bit.c | ||
| xfs_bit.h | ||
| xfs_bmap.c | ||
| xfs_bmap.h | ||
| xfs_bmap_btree.c | ||
| xfs_bmap_btree.h | ||
| xfs_btree.c | ||
| xfs_btree.h | ||
| xfs_buf_item.c | ||
| xfs_buf_item.h | ||
| xfs_clnt.h | ||
| xfs_da_btree.c | ||
| xfs_da_btree.h | ||
| xfs_dfrag.c | ||
| xfs_dfrag.h | ||
| xfs_dinode.h | ||
| xfs_dir2.c | ||
| xfs_dir2.h | ||
| xfs_dir2_block.c | ||
| xfs_dir2_block.h | ||
| xfs_dir2_data.c | ||
| xfs_dir2_data.h | ||
| xfs_dir2_leaf.c | ||
| xfs_dir2_leaf.h | ||
| xfs_dir2_node.c | ||
| xfs_dir2_node.h | ||
| xfs_dir2_sf.c | ||
| xfs_dir2_sf.h | ||
| xfs_dir2_trace.c | ||
| xfs_dir2_trace.h | ||
| xfs_dmapi.h | ||
| xfs_dmops.c | ||
| xfs_error.c | ||
| xfs_error.h | ||
| xfs_extfree_item.c | ||
| xfs_extfree_item.h | ||
| xfs_filestream.c | ||
| xfs_filestream.h | ||
| xfs_fs.h | ||
| xfs_fsops.c | ||
| xfs_fsops.h | ||
| xfs_ialloc.c | ||
| xfs_ialloc.h | ||
| xfs_ialloc_btree.c | ||
| xfs_ialloc_btree.h | ||
| xfs_iget.c | ||
| xfs_imap.h | ||
| xfs_inode.c | ||
| xfs_inode.h | ||
| xfs_inode_item.c | ||
| xfs_inode_item.h | ||
| xfs_inum.h | ||
| xfs_iomap.c | ||
| xfs_iomap.h | ||
| xfs_itable.c | ||
| xfs_itable.h | ||
| xfs_log.c | ||
| xfs_log.h | ||
| xfs_log_priv.h | ||
| xfs_log_recover.c | ||
| xfs_log_recover.h | ||
| xfs_mount.c | ||
| xfs_mount.h | ||
| xfs_mru_cache.c | ||
| xfs_mru_cache.h | ||
| xfs_qmops.c | ||
| xfs_quota.h | ||
| xfs_refcache.h | ||
| xfs_rename.c | ||
| xfs_rtalloc.c | ||
| xfs_rtalloc.h | ||
| xfs_rw.c | ||
| xfs_rw.h | ||
| xfs_sb.h | ||
| xfs_trans.c | ||
| xfs_trans.h | ||
| xfs_trans_ail.c | ||
| xfs_trans_buf.c | ||
| xfs_trans_extfree.c | ||
| xfs_trans_inode.c | ||
| xfs_trans_item.c | ||
| xfs_trans_priv.h | ||
| xfs_trans_space.h | ||
| xfs_types.h | ||
| xfs_utils.c | ||
| xfs_utils.h | ||
| xfs_vfsops.c | ||
| xfs_vfsops.h | ||
| xfs_vnodeops.c | ||
| xfs_vnodeops.h | ||