From a88cc108f6f39e56577793f66ac69eb0e18ae099 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Mon, 17 Mar 2014 12:21:54 +0000
Subject: [PATCH] lib: Export interval_tree
lib/interval_tree.c provides a simple interface for an interval-tree
(an augmented red-black tree) but is only built when testing the generic
macros for building interval-trees. For drivers with modest needs,
export the simple interval-tree library as is.
v2: Lots of help from Michel Lespinasse to only compile the code
as required:
- make INTERVAL_TREE a config option
- make INTERVAL_TREE_TEST select the library functions
and sanitize the filenames & Makefile
- prepare interval_tree for being built as a module if required
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Lespinasse <walken@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Michel Lespinasse <walken@google.com>
[Acked for inclusion via drm/i915 by Andrew Morton.]
[danvet: switch to _GPL as per the mailing list discussion.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---
lib/Kconfig | 14 ++++++++++++++
lib/Kconfig.debug | 1 +
lib/Makefile | 3 +--
lib/interval_tree.c | 6 ++++++
...erval_tree_test_main.c => interval_tree_test.c} | 0
5 files changed, 22 insertions(+), 2 deletions(-)
rename lib/{interval_tree_test_main.c => interval_tree_test.c} (100%)
diff --git a/lib/Kconfig b/lib/Kconfig
index 4771fb3f4da4d..334f7722a9992 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -331,6 +331,20 @@ config TEXTSEARCH_FSM
config BTREE
boolean
+config INTERVAL_TREE
+ boolean
+ help
+ Simple, embeddable, interval-tree. Can find the start of an
+ overlapping range in log(n) time and then iterate over all
+ overlapping nodes. The algorithm is implemented as an
+ augmented rbtree.
+
+ See:
+
+ Documentation/rbtree.txt
+
+ for more information.
+
config ASSOCIATIVE_ARRAY
bool
help
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 819ac51202c01..4bff173fef0a9 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1496,6 +1496,7 @@ config RBTREE_TEST
config INTERVAL_TREE_TEST
tristate "Interval tree test"
depends on m && DEBUG_KERNEL
+ select INTERVAL_TREE
help
A benchmark measuring the performance of the interval tree library
diff --git a/lib/Makefile b/lib/Makefile
index 0cd7b68e1382d..2c6c1a42e1d2f 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -50,6 +50,7 @@ CFLAGS_hweight.o = $(subst $(quote),,$(CONFIG_ARCH_HWEIGHT_CFLAGS))
obj-$(CONFIG_GENERIC_HWEIGHT) += hweight.o
obj-$(CONFIG_BTREE) += btree.o
+obj-$(CONFIG_INTERVAL_TREE) += interval_tree.o
obj-$(CONFIG_ASSOCIATIVE_ARRAY) += assoc_array.o
obj-$(CONFIG_DEBUG_PREEMPT) += smp_processor_id.o
obj-$(CONFIG_DEBUG_LIST) += list_debug.o
@@ -156,8 +157,6 @@ lib-$(CONFIG_LIBFDT) += $(libfdt_files)
obj-$(CONFIG_RBTREE_TEST) += rbtree_test.o
obj-$(CONFIG_INTERVAL_TREE_TEST) += interval_tree_test.o
-interval_tree_test-objs := interval_tree_test_main.o interval_tree.o
-
obj-$(CONFIG_PERCPU_TEST) += percpu_test.o
obj-$(CONFIG_ASN1) += asn1_decoder.o
diff --git a/lib/interval_tree.c b/lib/interval_tree.c
index e6eb406f2d65d..f367f9ad544c3 100644
--- a/lib/interval_tree.c
+++ b/lib/interval_tree.c
@@ -1,6 +1,7 @@
#include <linux/init.h>
#include <linux/interval_tree.h>
#include <linux/interval_tree_generic.h>
+#include <linux/module.h>
#define START(node) ((node)->start)
#define LAST(node) ((node)->last)
@@ -8,3 +9,8 @@
INTERVAL_TREE_DEFINE(struct interval_tree_node, rb,
unsigned long, __subtree_last,
START, LAST,, interval_tree)
+
+EXPORT_SYMBOL_GPL(interval_tree_insert);
+EXPORT_SYMBOL_GPL(interval_tree_remove);
+EXPORT_SYMBOL_GPL(interval_tree_iter_first);
+EXPORT_SYMBOL_GPL(interval_tree_iter_next);
diff --git a/lib/interval_tree_test_main.c b/lib/interval_tree_test.c
similarity index 100%
rename from lib/interval_tree_test_main.c
rename to lib/interval_tree_test.c
--
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