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Commit 147e615f authored by Michel Lespinasse's avatar Michel Lespinasse Committed by Linus Torvalds
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prio_tree: remove 

After both prio_tree users have been converted to use red-black trees,
there is no need to keep around the prio tree library anymore.
Signed-off-by: default avatarMichel 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: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 85d3a316
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Documentation/00-INDEX
View file @ 147e615f
......@@ -270,8 +270,6 @@ preempt-locking.txt
- info on locking under a preemptive kernel.
printk-formats.txt
- how to get printk format specifiers right
prio_tree.txt
- info on radix-priority-search-tree use for indexing vmas.
ramoops.txt
- documentation of the ramoops oops/panic logging module.
rbtree.txt
......
Documentation/prio_tree.txt deleted 100644 → 0
View file @ 85d3a316
The prio_tree.c code indexes vmas using 3 different indexes:
* heap_index = vm_pgoff + vm_size_in_pages : end_vm_pgoff
* radix_index = vm_pgoff : start_vm_pgoff
* size_index = vm_size_in_pages
A regular radix-priority-search-tree indexes vmas using only heap_index and
radix_index. The conditions for indexing are:
* ->heap_index >= ->left->heap_index &&
->heap_index >= ->right->heap_index
* if (->heap_index == ->left->heap_index)
then ->radix_index < ->left->radix_index;
* if (->heap_index == ->right->heap_index)
then ->radix_index < ->right->radix_index;
* nodes are hashed to left or right subtree using radix_index
similar to a pure binary radix tree.
A regular radix-priority-search-tree helps to store and query
intervals (vmas). However, a regular radix-priority-search-tree is only
suitable for storing vmas with different radix indices (vm_pgoff).
Therefore, the prio_tree.c extends the regular radix-priority-search-tree
to handle many vmas with the same vm_pgoff. Such vmas are handled in
2 different ways: 1) All vmas with the same radix _and_ heap indices are
linked using vm_set.list, 2) if there are many vmas with the same radix
index, but different heap indices and if the regular radix-priority-search
tree cannot index them all, we build an overflow-sub-tree that indexes such
vmas using heap and size indices instead of heap and radix indices. For
example, in the figure below some vmas with vm_pgoff = 0 (zero) are
indexed by regular radix-priority-search-tree whereas others are pushed
into an overflow-subtree. Note that all vmas in an overflow-sub-tree have
the same vm_pgoff (radix_index) and if necessary we build different
overflow-sub-trees to handle each possible radix_index. For example,
in figure we have 3 overflow-sub-trees corresponding to radix indices
0, 2, and 4.
In the final tree the first few (prio_tree_root->index_bits) levels
are indexed using heap and radix indices whereas the overflow-sub-trees below
those levels (i.e. levels prio_tree_root->index_bits + 1 and higher) are
indexed using heap and size indices. In overflow-sub-trees the size_index
is used for hashing the nodes to appropriate places.
Now, an example prio_tree:
vmas are represented [radix_index, size_index, heap_index]
i.e., [start_vm_pgoff, vm_size_in_pages, end_vm_pgoff]
level prio_tree_root->index_bits = 3
-----
_
0 [0,7,7] |
/ \ |
------------------ ------------ | Regular
/ \ | radix priority
1 [1,6,7] [4,3,7] | search tree
/ \ / \ |
------- ----- ------ ----- | heap-and-radix
/ \ / \ | indexed
2 [0,6,6] [2,5,7] [5,2,7] [6,1,7] |
/ \ / \ / \ / \ |
3 [0,5,5] [1,5,6] [2,4,6] [3,4,7] [4,2,6] [5,1,6] [6,0,6] [7,0,7] |
/ / / _
/ / / _
4 [0,4,4] [2,3,5] [4,1,5] |
/ / / |
5 [0,3,3] [2,2,4] [4,0,4] | Overflow-sub-trees
/ / |
6 [0,2,2] [2,1,3] | heap-and-size
/ / | indexed
7 [0,1,1] [2,0,2] |
/ |
8 [0,0,0] |
_
Note that we use prio_tree_root->index_bits to optimize the height
of the heap-and-radix indexed tree. Since prio_tree_root->index_bits is
set according to the maximum end_vm_pgoff mapped, we are sure that all
bits (in vm_pgoff) above prio_tree_root->index_bits are 0 (zero). Therefore,
we only use the first prio_tree_root->index_bits as radix_index.
Whenever index_bits is increased in prio_tree_expand, we shuffle the tree
to make sure that the first prio_tree_root->index_bits levels of the tree
is indexed properly using heap and radix indices.
We do not optimize the height of overflow-sub-trees using index_bits.
The reason is: there can be many such overflow-sub-trees and all of
them have to be suffled whenever the index_bits increases. This may involve
walking the whole prio_tree in prio_tree_insert->prio_tree_expand code
path which is not desirable. Hence, we do not optimize the height of the
heap-and-size indexed overflow-sub-trees using prio_tree->index_bits.
Instead the overflow sub-trees are indexed using full BITS_PER_LONG bits
of size_index. This may lead to skewed sub-trees because most of the
higher significant bits of the size_index are likely to be 0 (zero). In
the example above, all 3 overflow-sub-trees are skewed. This may marginally
affect the performance. However, processes rarely map many vmas with the
same start_vm_pgoff but different end_vm_pgoffs. Therefore, we normally
do not require overflow-sub-trees to index all vmas.
From the above discussion it is clear that the maximum height of
a prio_tree can be prio_tree_root->index_bits + BITS_PER_LONG.
However, in most of the common cases we do not need overflow-sub-trees,
so the tree height in the common cases will be prio_tree_root->index_bits.
It is fair to mention here that the prio_tree_root->index_bits
is increased on demand, however, the index_bits is not decreased when
vmas are removed from the prio_tree. That's tricky to do. Hence, it's
left as a home work problem.
include/linux/prio_tree.h deleted 100644 → 0
View file @ 85d3a316
#ifndef _LINUX_PRIO_TREE_H
#define _LINUX_PRIO_TREE_H
/*
* K&R 2nd ed. A8.3 somewhat obliquely hints that initial sequences of struct
* fields with identical types should end up at the same location. We'll use
* this until we can scrap struct raw_prio_tree_node.
*
* Note: all this could be done more elegantly by using unnamed union/struct
* fields. However, gcc 2.95.3 and apparently also gcc 3.0.4 don't support this
* language extension.
*/
struct raw_prio_tree_node {
struct prio_tree_node *left;
struct prio_tree_node *right;
struct prio_tree_node *parent;
};
struct prio_tree_node {
struct prio_tree_node *left;
struct prio_tree_node *right;
struct prio_tree_node *parent;
unsigned long start;
unsigned long last; /* last location _in_ interval */
};
struct prio_tree_root {
struct prio_tree_node *prio_tree_node;
unsigned short index_bits;
unsigned short raw;
/*
* 0: nodes are of type struct prio_tree_node
* 1: nodes are of type raw_prio_tree_node
*/
};
struct prio_tree_iter {
struct prio_tree_node *cur;
unsigned long mask;
unsigned long value;
int size_level;
struct prio_tree_root *root;
pgoff_t r_index;
pgoff_t h_index;
};
static inline void prio_tree_iter_init(struct prio_tree_iter *iter,
struct prio_tree_root *root, pgoff_t r_index, pgoff_t h_index)
{
iter->root = root;
iter->r_index = r_index;
iter->h_index = h_index;
iter->cur = NULL;
}
#define __INIT_PRIO_TREE_ROOT(ptr, _raw) \
do { \
(ptr)->prio_tree_node = NULL; \
(ptr)->index_bits = 1; \
(ptr)->raw = (_raw); \
} while (0)
#define INIT_PRIO_TREE_ROOT(ptr) __INIT_PRIO_TREE_ROOT(ptr, 0)
#define INIT_RAW_PRIO_TREE_ROOT(ptr) __INIT_PRIO_TREE_ROOT(ptr, 1)
#define INIT_PRIO_TREE_NODE(ptr) \
do { \
(ptr)->left = (ptr)->right = (ptr)->parent = (ptr); \
} while (0)
#define INIT_PRIO_TREE_ITER(ptr) \
do { \
(ptr)->cur = NULL; \
(ptr)->mask = 0UL; \
(ptr)->value = 0UL; \
(ptr)->size_level = 0; \
} while (0)
#define prio_tree_entry(ptr, type, member) \
((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member)))
static inline int prio_tree_empty(const struct prio_tree_root *root)
{
return root->prio_tree_node == NULL;
}
static inline int prio_tree_root(const struct prio_tree_node *node)
{
return node->parent == node;
}
static inline int prio_tree_left_empty(const struct prio_tree_node *node)
{
return node->left == node;
}
static inline int prio_tree_right_empty(const struct prio_tree_node *node)
{
return node->right == node;
}
struct prio_tree_node *prio_tree_replace(struct prio_tree_root *root,
struct prio_tree_node *old, struct prio_tree_node *node);
struct prio_tree_node *prio_tree_insert(struct prio_tree_root *root,
struct prio_tree_node *node);
void prio_tree_remove(struct prio_tree_root *root, struct prio_tree_node *node);
struct prio_tree_node *prio_tree_next(struct prio_tree_iter *iter);
#define raw_prio_tree_replace(root, old, node) \
prio_tree_replace(root, (struct prio_tree_node *) (old), \
(struct prio_tree_node *) (node))
#define raw_prio_tree_insert(root, node) \
prio_tree_insert(root, (struct prio_tree_node *) (node))
#define raw_prio_tree_remove(root, node) \
prio_tree_remove(root, (struct prio_tree_node *) (node))
#endif /* _LINUX_PRIO_TREE_H */
init/main.c
View file @ 147e615f
......@@ -86,7 +86,6 @@ extern void init_IRQ(void);
extern void fork_init(unsigned long);
extern void mca_init(void);
extern void sbus_init(void);
extern void prio_tree_init(void);
extern void radix_tree_init(void);
#ifndef CONFIG_DEBUG_RODATA
static inline void mark_rodata_ro(void) { }
......@@ -547,7 +546,6 @@ asmlinkage void __init start_kernel(void)
/* init some links before init_ISA_irqs() */
early_irq_init();
init_IRQ();
prio_tree_init();
init_timers();
hrtimers_init();
softirq_init();
......
lib/Kconfig.debug
View file @ 147e615f
......@@ -1289,12 +1289,6 @@ config RBTREE_TEST
A benchmark measuring the performance of the rbtree library.
Also includes rbtree invariant checks.
config PRIO_TREE_TEST
tristate "Prio tree test"
depends on m && DEBUG_KERNEL
help
A benchmark measuring the performance of the prio tree library
config INTERVAL_TREE_TEST
tristate "Interval tree test"
depends on m && DEBUG_KERNEL
......
lib/Makefile
View file @ 147e615f
......@@ -9,7 +9,7 @@ endif
lib-y := ctype.o string.o vsprintf.o cmdline.o \
rbtree.o radix-tree.o dump_stack.o timerqueue.o\
idr.o int_sqrt.o extable.o prio_tree.o \
idr.o int_sqrt.o extable.o \
sha1.o md5.o irq_regs.o reciprocal_div.o argv_split.o \
proportions.o flex_proportions.o prio_heap.o ratelimit.o show_mem.o \
is_single_threaded.o plist.o decompress.o
......@@ -141,7 +141,6 @@ $(foreach file, $(libfdt_files), \
lib-$(CONFIG_LIBFDT) += $(libfdt_files)
obj-$(CONFIG_RBTREE_TEST) += rbtree_test.o
obj-$(CONFIG_PRIO_TREE_TEST) += prio_tree_test.o
obj-$(CONFIG_INTERVAL_TREE_TEST) += interval_tree_test.o
interval_tree_test-objs := interval_tree_test_main.o interval_tree.o
......
lib/prio_tree.c deleted 100644 → 0
View file @ 85d3a316
/*
* lib/prio_tree.c - priority search tree
*
* Copyright (C) 2004, Rajesh Venkatasubramanian <vrajesh@umich.edu>
*
* This file is released under the GPL v2.
*
* Based on the radix priority search tree proposed by Edward M. McCreight
* SIAM Journal of Computing, vol. 14, no.2, pages 257-276, May 1985
*
* 02Feb2004 Initial version
*/
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/prio_tree.h>
#include <linux/export.h>
/*
* A clever mix of heap and radix trees forms a radix priority search tree (PST)
* which is useful for storing intervals, e.g, we can consider a vma as a closed
* interval of file pages [offset_begin, offset_end], and store all vmas that
* map a file in a PST. Then, using the PST, we can answer a stabbing query,
* i.e., selecting a set of stored intervals (vmas) that overlap with (map) a
* given input interval X (a set of consecutive file pages), in "O(log n + m)"
* time where 'log n' is the height of the PST, and 'm' is the number of stored
* intervals (vmas) that overlap (map) with the input interval X (the set of
* consecutive file pages).
*
* In our implementation, we store closed intervals of the form [radix_index,
* heap_index]. We assume that always radix_index <= heap_index. McCreight's PST
* is designed for storing intervals with unique radix indices, i.e., each
* interval have different radix_index. However, this limitation can be easily
* overcome by using the size, i.e., heap_index - radix_index, as part of the
* index, so we index the tree using [(radix_index,size), heap_index].
*
* When the above-mentioned indexing scheme is used, theoretically, in a 32 bit
* machine, the maximum height of a PST can be 64. We can use a balanced version
* of the priority search tree to optimize the tree height, but the balanced
* tree proposed by McCreight is too complex and memory-hungry for our purpose.
*/
/*
* The following macros are used for implementing prio_tree for i_mmap
*/
static void get_index(const struct prio_tree_root *root,
const struct prio_tree_node *node,
unsigned long *radix, unsigned long *heap)
{
*radix = node->start;
*heap = node->last;
}
static unsigned long index_bits_to_maxindex[BITS_PER_LONG];
void __init prio_tree_init(void)
{
unsigned int i;
for (i = 0; i < ARRAY_SIZE(index_bits_to_maxindex) - 1; i++)
index_bits_to_maxindex[i] = (1UL << (i + 1)) - 1;
index_bits_to_maxindex[ARRAY_SIZE(index_bits_to_maxindex) - 1] = ~0UL;
}
/*
* Maximum heap_index that can be stored in a PST with index_bits bits
*/
static inline unsigned long prio_tree_maxindex(unsigned int bits)
{
return index_bits_to_maxindex[bits - 1];
}
static void prio_set_parent(struct prio_tree_node *parent,
struct prio_tree_node *child, bool left)
{
if (left)
parent->left = child;
else
parent->right = child;
child->parent = parent;
}
/*
* Extend a priority search tree so that it can store a node with heap_index
* max_heap_index. In the worst case, this algorithm takes O((log n)^2).
* However, this function is used rarely and the common case performance is
* not bad.
*/
static struct prio_tree_node *prio_tree_expand(struct prio_tree_root *root,
struct prio_tree_node *node, unsigned long max_heap_index)
{
struct prio_tree_node *prev;
if (max_heap_index > prio_tree_maxindex(root->index_bits))
root->index_bits++;
prev = node;
INIT_PRIO_TREE_NODE(node);
while (max_heap_index > prio_tree_maxindex(root->index_bits)) {
struct prio_tree_node *tmp = root->prio_tree_node;
root->index_bits++;
if (prio_tree_empty(root))
continue;
prio_tree_remove(root, root->prio_tree_node);
INIT_PRIO_TREE_NODE(tmp);
prio_set_parent(prev, tmp, true);
prev = tmp;
}
if (!prio_tree_empty(root))
prio_set_parent(prev, root->prio_tree_node, true);
root->prio_tree_node = node;
return node;
}
/*
* Replace a prio_tree_node with a new node and return the old node
*/
struct prio_tree_node *prio_tree_replace(struct prio_tree_root *root,
struct prio_tree_node *old, struct prio_tree_node *node)
{
INIT_PRIO_TREE_NODE(node);
if (prio_tree_root(old)) {
BUG_ON(root->prio_tree_node != old);
/*
* We can reduce root->index_bits here. However, it is complex
* and does not help much to improve performance (IMO).
*/
root->prio_tree_node = node;
} else
prio_set_parent(old->parent, node, old->parent->left == old);
if (!prio_tree_left_empty(old))
prio_set_parent(node, old->left, true);
if (!prio_tree_right_empty(old))
prio_set_parent(node, old->right, false);
return old;
}
/*
* Insert a prio_tree_node @node into a radix priority search tree @root. The
* algorithm typically takes O(log n) time where 'log n' is the number of bits
* required to represent the maximum heap_index. In the worst case, the algo
* can take O((log n)^2) - check prio_tree_expand.
*
* If a prior node with same radix_index and heap_index is already found in
* the tree, then returns the address of the prior node. Otherwise, inserts
* @node into the tree and returns @node.
*/
struct prio_tree_node *prio_tree_insert(struct prio_tree_root *root,
struct prio_tree_node *node)
{
struct prio_tree_node *cur, *res = node;
unsigned long radix_index, heap_index;
unsigned long r_index, h_index, index, mask;
int size_flag = 0;
get_index(root, node, &radix_index, &heap_index);
if (prio_tree_empty(root) ||
heap_index > prio_tree_maxindex(root->index_bits))
return prio_tree_expand(root, node, heap_index);
cur = root->prio_tree_node;
mask = 1UL << (root->index_bits - 1);
while (mask) {
get_index(root, cur, &r_index, &h_index);
if (r_index == radix_index && h_index == heap_index)
return cur;
if (h_index < heap_index ||
(h_index == heap_index && r_index > radix_index)) {
struct prio_tree_node *tmp = node;
node = prio_tree_replace(root, cur, node);
cur = tmp;
/* swap indices */
index = r_index;
r_index = radix_index;
radix_index = index;
index = h_index;
h_index = heap_index;
heap_index = index;
}
if (size_flag)
index = heap_index - radix_index;
else
index = radix_index;
if (index & mask) {
if (prio_tree_right_empty(cur)) {
INIT_PRIO_TREE_NODE(node);
prio_set_parent(cur, node, false);
return res;
} else
cur = cur->right;
} else {
if (prio_tree_left_empty(cur)) {
INIT_PRIO_TREE_NODE(node);
prio_set_parent(cur, node, true);
return res;
} else
cur = cur->left;
}
mask >>= 1;
if (!mask) {
mask = 1UL << (BITS_PER_LONG - 1);
size_flag = 1;
}
}
/* Should not reach here */
BUG();
return NULL;
}
EXPORT_SYMBOL(prio_tree_insert);
/*
* Remove a prio_tree_node @node from a radix priority search tree @root. The
* algorithm takes O(log n) time where 'log n' is the number of bits required
* to represent the maximum heap_index.
*/
void prio_tree_remove(struct prio_tree_root *root, struct prio_tree_node *node)
{
struct prio_tree_node *cur;
unsigned long r_index, h_index_right, h_index_left;
cur = node;
while (!prio_tree_left_empty(cur) || !prio_tree_right_empty(cur)) {
if (!prio_tree_left_empty(cur))
get_index(root, cur->left, &r_index, &h_index_left);
else {
cur = cur->right;
continue;
}
if (!prio_tree_right_empty(cur))
get_index(root, cur->right, &r_index, &h_index_right);
else {
cur = cur->left;
continue;
}
/* both h_index_left and h_index_right cannot be 0 */
if (h_index_left >= h_index_right)
cur = cur->left;
else
cur = cur->right;
}
if (prio_tree_root(cur)) {
BUG_ON(root->prio_tree_node != cur);
__INIT_PRIO_TREE_ROOT(root, root->raw);
return;
}
if (cur->parent->right == cur)
cur->parent->right = cur->parent;
else
cur->parent->left = cur->parent;
while (cur != node)
cur = prio_tree_replace(root, cur->parent, cur);
}
EXPORT_SYMBOL(prio_tree_remove);
static void iter_walk_down(struct prio_tree_iter *iter)
{
iter->mask >>= 1;
if (iter->mask) {
if (iter->size_level)
iter->size_level++;
return;
}
if (iter->size_level) {
BUG_ON(!prio_tree_left_empty(iter->cur));
BUG_ON(!prio_tree_right_empty(iter->cur));
iter->size_level++;
iter->mask = ULONG_MAX;
} else {
iter->size_level = 1;
iter->mask = 1UL << (BITS_PER_LONG - 1);
}
}
static void iter_walk_up(struct prio_tree_iter *iter)
{
if (iter->mask == ULONG_MAX)
iter->mask = 1UL;
else if (iter->size_level == 1)
iter->mask = 1UL;
else
iter->mask <<= 1;
if (iter->size_level)
iter->size_level--;
if (!iter->size_level && (iter->value & iter->mask))
iter->value ^= iter->mask;
}
/*
* Following functions help to enumerate all prio_tree_nodes in the tree that
* overlap with the input interval X [radix_index, heap_index]. The enumeration
* takes O(log n + m) time where 'log n' is the height of the tree (which is
* proportional to # of bits required to represent the maximum heap_index) and
* 'm' is the number of prio_tree_nodes that overlap the interval X.
*/
static struct prio_tree_node *prio_tree_left(struct prio_tree_iter *iter,
unsigned long *r_index, unsigned long *h_index)
{
if (prio_tree_left_empty(iter->cur))
return NULL;
get_index(iter->root, iter->cur->left, r_index, h_index);
if (iter->r_index <= *h_index) {
iter->cur = iter->cur->left;
iter_walk_down(iter);
return iter->cur;
}
return NULL;
}
static struct prio_tree_node *prio_tree_right(struct prio_tree_iter *iter,
unsigned long *r_index, unsigned long *h_index)
{
unsigned long value;
if (prio_tree_right_empty(iter->cur))
return NULL;
if (iter->size_level)
value = iter->value;
else
value = iter->value | iter->mask;
if (iter->h_index < value)
return NULL;
get_index(iter->root, iter->cur->right, r_index, h_index);
if (iter->r_index <= *h_index) {
iter->cur = iter->cur->right;
iter_walk_down(iter);
return iter->cur;
}
return NULL;
}
static struct prio_tree_node *prio_tree_parent(struct prio_tree_iter *iter)
{
iter->cur = iter->cur->parent;
iter_walk_up(iter);
return iter->cur;
}
static inline int overlap(struct prio_tree_iter *iter,
unsigned long r_index, unsigned long h_index)
{
return iter->h_index >= r_index && iter->r_index <= h_index;
}
/*
* prio_tree_first:
*
* Get the first prio_tree_node that overlaps with the interval [radix_index,
* heap_index]. Note that always radix_index <= heap_index. We do a pre-order
* traversal of the tree.
*/
static struct prio_tree_node *prio_tree_first(struct prio_tree_iter *iter)
{
struct prio_tree_root *root;
unsigned long r_index, h_index;
INIT_PRIO_TREE_ITER(iter);
root = iter->root;
if (prio_tree_empty(root))
return NULL;
get_index(root, root->prio_tree_node, &r_index, &h_index);
if (iter->r_index > h_index)
return NULL;
iter->mask = 1UL << (root->index_bits - 1);
iter->cur = root->prio_tree_node;
while (1) {
if (overlap(iter, r_index, h_index))
return iter->cur;
if (prio_tree_left(iter, &r_index, &h_index))
continue;
if (prio_tree_right(iter, &r_index, &h_index))
continue;
break;
}
return NULL;
}
/*
* prio_tree_next:
*
* Get the next prio_tree_node that overlaps with the input interval in iter
*/
struct prio_tree_node *prio_tree_next(struct prio_tree_iter *iter)
{
unsigned long r_index, h_index;
if (iter->cur == NULL)
return prio_tree_first(iter);
repeat:
while (prio_tree_left(iter, &r_index, &h_index))
if (overlap(iter, r_index, h_index))
return iter->cur;
while (!prio_tree_right(iter, &r_index, &h_index)) {
while (!prio_tree_root(iter->cur) &&
iter->cur->parent->right == iter->cur)
prio_tree_parent(iter);
if (prio_tree_root(iter->cur))
return NULL;
prio_tree_parent(iter);
}
if (overlap(iter, r_index, h_index))
return iter->cur;
goto repeat;
}
EXPORT_SYMBOL(prio_tree_next);
lib/prio_tree_test.c deleted 100644 → 0
View file @ 85d3a316
#include <linux/module.h>
#include <linux/prio_tree.h>
#include <linux/random.h>
#include <asm/timex.h>
#define NODES 100
#define PERF_LOOPS 100000
#define SEARCHES 100
#define SEARCH_LOOPS 10000
static struct prio_tree_root root;
static struct prio_tree_node nodes[NODES];
static u32 queries[SEARCHES];
static struct rnd_state rnd;
static inline unsigned long
search(unsigned long query, struct prio_tree_root *root)
{
struct prio_tree_iter iter;
unsigned long results = 0;
prio_tree_iter_init(&iter, root, query, query);
while (prio_tree_next(&iter))
results++;
return results;
}
static void init(void)
{
int i;
for (i = 0; i < NODES; i++) {
u32 a = prandom32(&rnd), b = prandom32(&rnd);
if (a <= b) {
nodes[i].start = a;
nodes[i].last = b;
} else {
nodes[i].start = b;
nodes[i].last = a;
}
}
for (i = 0; i < SEARCHES; i++)
queries[i] = prandom32(&rnd);
}
static int prio_tree_test_init(void)
{
int i, j;
unsigned long results;
cycles_t time1, time2, time;
printk(KERN_ALERT "prio tree insert/remove");
prandom32_seed(&rnd, 3141592653589793238ULL);
INIT_PRIO_TREE_ROOT(&root);
init();
time1 = get_cycles();
for (i = 0; i < PERF_LOOPS; i++) {
for (j = 0; j < NODES; j++)
prio_tree_insert(&root, nodes + j);
for (j = 0; j < NODES; j++)
prio_tree_remove(&root, nodes + j);
}
time2 = get_cycles();
time = time2 - time1;
time = div_u64(time, PERF_LOOPS);
printk(" -> %llu cycles\n", (unsigned long long)time);
printk(KERN_ALERT "prio tree search");
for (j = 0; j < NODES; j++)
prio_tree_insert(&root, nodes + j);
time1 = get_cycles();
results = 0;
for (i = 0; i < SEARCH_LOOPS; i++)
for (j = 0; j < SEARCHES; j++)
results += search(queries[j], &root);
time2 = get_cycles();
time = time2 - time1;
time = div_u64(time, SEARCH_LOOPS);
results = div_u64(results, SEARCH_LOOPS);
printk(" -> %llu cycles (%lu results)\n",
(unsigned long long)time, results);
return -EAGAIN; /* Fail will directly unload the module */
}
static void prio_tree_test_exit(void)
{
printk(KERN_ALERT "test exit\n");
}
module_init(prio_tree_test_init)
module_exit(prio_tree_test_exit)
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Michel Lespinasse");
MODULE_DESCRIPTION("Prio Tree test");
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