libceph: advance pagelist with list_rotate_left()
authorAlex Elder <elder@inktank.com>
Thu, 7 Mar 2013 05:39:38 +0000 (23:39 -0600)
committerSage Weil <sage@inktank.com>
Thu, 2 May 2013 04:16:34 +0000 (21:16 -0700)
commit35c7bfbcd4fabded090e5ab316a1cbf053a0a980
treedcb5139eebfc6a7e77f582d7f1eb0618e4885377
parente788182fa6c1a400076278a75d0efa0a8a08e4ec
libceph: advance pagelist with list_rotate_left()

While processing an outgoing pagelist (either the data pagelist or
trail) in a ceph message, the messenger cycles through each of the
pages on the list.  This is accomplished in out_msg_pos_next(), if
the end of the first page on the list is reached, the first page is
moved to the end of the list.

There is a list operation, list_rotate_left(), which performs
exactly this operation, and by using it, what's really going on
becomes more obvious.

So replace these two list_move_tail() calls with list_rotate_left().

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
net/ceph/messenger.c