fs/dax.c: fix inefficiency in dax_writeback_mapping_range()
authorJan Kara <jack@suse.cz>
Fri, 23 Jun 2017 22:08:46 +0000 (15:08 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 23 Jun 2017 23:15:55 +0000 (16:15 -0700)
commit1eb643d02b21412e603b42cdd96010a2ac31c05f
treeaa77fd98679a5916f1dbc620d389f6d4146ff71e
parent9fa4eb8e490a28de40964b1b0e583d8db4c7e57c
fs/dax.c: fix inefficiency in dax_writeback_mapping_range()

dax_writeback_mapping_range() fails to update iteration index when
searching radix tree for entries needing cache flushing.  Thus each
pagevec worth of entries is searched starting from the start which is
inefficient and prone to livelocks.  Update index properly.

Link: http://lkml.kernel.org/r/20170619124531.21491-1-jack@suse.cz
Fixes: 9973c98ecfda3 ("dax: add support for fsync/sync")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/dax.c