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authorMichel Lespinasse <walken@google.com>2012-10-09 01:31:33 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-09 09:22:40 +0200
commit9c079add0d0f45220f4bb37febf0621137ec2d38 (patch)
treece6ba6d7e2d517a2004de856c882f2a08af12be2 /Documentation
parentprio_tree: remove (diff)
downloadlinux-9c079add0d0f45220f4bb37febf0621137ec2d38.tar.xz
linux-9c079add0d0f45220f4bb37febf0621137ec2d38.zip
rbtree: move augmented rbtree functionality to rbtree_augmented.h
Provide rb_insert_augmented() and rb_erase_augmented() through a new rbtree_augmented.h include file. rb_erase_augmented() is defined there as an __always_inline function, in order to allow inlining of augmented rbtree callbacks into it. Since this generates a relatively large function, each augmented rbtree user should make sure to have a single call site. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/rbtree.txt13
1 files changed, 13 insertions, 0 deletions
diff --git a/Documentation/rbtree.txt b/Documentation/rbtree.txt
index 0a0b6dce3e08..61b6c48871a0 100644
--- a/Documentation/rbtree.txt
+++ b/Documentation/rbtree.txt
@@ -202,6 +202,14 @@ An rbtree user who wants this feature will have to call the augmentation
functions with the user provided augmentation callback when inserting
and erasing nodes.
+C files implementing augmented rbtree manipulation must include
+<linux/rbtree_augmented.h> instead of <linus/rbtree.h>. Note that
+linux/rbtree_augmented.h exposes some rbtree implementations details
+you are not expected to rely on; please stick to the documented APIs
+there and do not include <linux/rbtree_augmented.h> from header files
+either so as to minimize chances of your users accidentally relying on
+such implementation details.
+
On insertion, the user must update the augmented information on the path
leading to the inserted node, then call rb_link_node() as usual and
rb_augment_inserted() instead of the usual rb_insert_color() call.
@@ -227,6 +235,11 @@ In both cases, the callbacks are provided through struct rb_augment_callbacks.
subtree to a newly assigned subtree root AND recomputes the augmented
information for the former subtree root.
+The compiled code for rb_erase_augmented() may inline the propagation and
+copy callbacks, which results in a large function, so each augmented rbtree
+user should have a single rb_erase_augmented() call site in order to limit
+compiled code size.
+
Sample usage: