Commit Graph

6 Commits

Author SHA1 Message Date
Artem Bityutskiy f4b477c473 rbtree: add const qualifier to some functions
The 'rb_first()', 'rb_last()', 'rb_next()' and 'rb_prev()' calls
take a pointer to an RB node or RB root. They do not change the
pointed objects, so add a 'const' qualifier in order to make life
of the users of these functions easier.

Indeed, if I have my own constant pointer &const struct my_type *p,
and I call 'rb_next(&p->rb)', I get a GCC warning:

warning: passing argument 1 of ‘rb_next’ discards qualifiers from pointer target type

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-10 06:04:33 -08:00
Jens Axboe 10fd48f237 [PATCH] rbtree: fixed reversed RB_EMPTY_NODE and rb_next/prev
The conditions got reserved. Also make rb_next() and rb_prev() check
for the empty condition.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:26:56 +02:00
David Woodhouse 2f3243aebd [RBTREE] Switch rb_colour() et al to en_US spelling of 'color' for consistency
Since rb_insert_color() is part of the _public_ API, while the others are
purely internal, switch to be consistent with that.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-06-05 20:19:05 +01:00
David Woodhouse 55a981027f [RBTREE] Merge colour and parent fields of struct rb_node.
We only used a single bit for colour information, so having a whole
machine word of space allocated for it was a bit wasteful. Instead,
store it in the lowest bit of the 'parent' pointer, since that was
always going to be aligned anyway.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-04-21 13:35:51 +01:00
David Woodhouse 1975e59375 [RBTREE] Remove dead code in rb_erase()
Observe rb_erase(), when the victim node 'old' has two children so
neither of the simple cases at the beginning are taken.

Observe that it effectively does an 'rb_next()' operation to find the
next (by value) node in the tree. That is; we go to the victim's
right-hand child and then follow left-hand pointers all the way
down the tree as far as we can until we find the next node 'node'. We
end up with 'node' being either the same immediate right-hand child of
'old', or one of its descendants on the far left-hand side.

For a start, we _know_ that 'node' has a parent. We can drop that check.

We also know that if 'node's parent is 'old', then 'node' is the
right-hand child of its parent. And that if 'node's parent is _not_
'old', then 'node' is the left-hand child of its parent.

So instead of checking for 'node->rb_parent == old' in one place and
also checking 'node's heritage separately when we're trying to change
its link from its parent, we can shuffle things around a bit and do
it like this...

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-04-21 13:30:36 +01:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00