>>> On 21.11.17 at 16:19, <[email protected]> wrote: > From: Michel Lespinasse <[email protected]> > > Empty nodes have no color. We can make use of this property to simplify > the code emitted by the RB_EMPTY_NODE and RB_CLEAR_NODE macros. Also, > we can get rid of the rb_init_node function which had been introduced by > commit 88d19cf37952 ("timers: Add rb_init_node() to allow for stack > allocated rb nodes") to avoid some issue with the empty node's color not > being initialized. > > I'm not sure what the RB_EMPTY_NODE checks in rb_prev() / rb_next() are > doing there, though. axboe introduced them in commit 10fd48f2376d > ("rbtree: fixed reversed RB_EMPTY_NODE and rb_next/prev"). The way I > see it, the 'empty node' abstraction is only used by rbtree users to > flag nodes that they haven't inserted in any rbtree, so asking the > predecessor or successor of such nodes doesn't make any sense. > > One final rb_init_node() caller was recently added in sysctl code to > implement faster sysctl name lookups. This code doesn't make use of > RB_EMPTY_NODE at all, and from what I could see it only called > rb_init_node() under the mistaken assumption that such initialization was > required before node insertion. > > [[email protected]: fix net/ceph/osd_client.c build] > Signed-off-by: Michel Lespinasse <[email protected]> > Cc: Andrea Arcangeli <[email protected]> > Acked-by: David Woodhouse <[email protected]> > Cc: Rik van Riel <[email protected]> > Cc: Peter Zijlstra <[email protected]> > Cc: Daniel Santos <[email protected]> > Cc: Jens Axboe <[email protected]> > Cc: "Eric W. Biederman" <[email protected]> > Cc: John Stultz <[email protected]> > Signed-off-by: Stephen Rothwell <[email protected]> > Signed-off-by: Andrew Morton <[email protected]> > Signed-off-by: Linus Torvalds <[email protected]> > [Linux commit 4c199a93a2d36b277a9fd209a0f2793f8460a215] > > Ported rbtree.h and rbtree.c changes which are relevant to Xen. > > Signed-off-by: Praveen Kumar <[email protected]>
Acked-by: Jan Beulich <[email protected]> _______________________________________________ Xen-devel mailing list [email protected] https://lists.xenproject.org/mailman/listinfo/xen-devel
