[PATCH 4.4 03/40] lib/rbtree_test.c: make input module parameters

From: Greg Kroah-Hartman
Date: Thu Dec 20 2018 - 04:44:22 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

[ Upstream commit 223f8911eace60c787f8767c25148b80ece9732a ]

Allows for more flexible debugging.

Link: http://lkml.kernel.org/r/20170719014603.19029-5-dave@xxxxxxxxxxxx
Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
lib/rbtree_test.c | 55 +++++++++++++++++++++++++++++------------------
1 file changed, 34 insertions(+), 21 deletions(-)

diff --git a/lib/rbtree_test.c b/lib/rbtree_test.c
index 8b3c9dc88262..e83331aa1b7f 100644
--- a/lib/rbtree_test.c
+++ b/lib/rbtree_test.c
@@ -1,11 +1,18 @@
#include <linux/module.h>
+#include <linux/moduleparam.h>
#include <linux/rbtree_augmented.h>
#include <linux/random.h>
+#include <linux/slab.h>
#include <asm/timex.h>

-#define NODES 100
-#define PERF_LOOPS 100000
-#define CHECK_LOOPS 100
+#define __param(type, name, init, msg) \
+ static type name = init; \
+ module_param(name, type, 0444); \
+ MODULE_PARM_DESC(name, msg);
+
+__param(int, nnodes, 100, "Number of nodes in the rb-tree");
+__param(int, perf_loops, 100000, "Number of iterations modifying the rb-tree");
+__param(int, check_loops, 100, "Number of iterations modifying and verifying the rb-tree");

struct test_node {
u32 key;
@@ -17,7 +24,7 @@ struct test_node {
};

static struct rb_root root = RB_ROOT;
-static struct test_node nodes[NODES];
+static struct test_node *nodes = NULL;

static struct rnd_state rnd;

@@ -95,7 +102,7 @@ static void erase_augmented(struct test_node *node, struct rb_root *root)
static void init(void)
{
int i;
- for (i = 0; i < NODES; i++) {
+ for (i = 0; i < nnodes; i++) {
nodes[i].key = prandom_u32_state(&rnd);
nodes[i].val = prandom_u32_state(&rnd);
}
@@ -177,6 +184,10 @@ static int __init rbtree_test_init(void)
int i, j;
cycles_t time1, time2, time;

+ nodes = kmalloc(nnodes * sizeof(*nodes), GFP_KERNEL);
+ if (!nodes)
+ return -ENOMEM;
+
printk(KERN_ALERT "rbtree testing");

prandom_seed_state(&rnd, 3141592653589793238ULL);
@@ -184,27 +195,27 @@ static int __init rbtree_test_init(void)

time1 = get_cycles();

- for (i = 0; i < PERF_LOOPS; i++) {
- for (j = 0; j < NODES; j++)
+ for (i = 0; i < perf_loops; i++) {
+ for (j = 0; j < nnodes; j++)
insert(nodes + j, &root);
- for (j = 0; j < NODES; j++)
+ for (j = 0; j < nnodes; j++)
erase(nodes + j, &root);
}

time2 = get_cycles();
time = time2 - time1;

- time = div_u64(time, PERF_LOOPS);
+ time = div_u64(time, perf_loops);
printk(" -> %llu cycles\n", (unsigned long long)time);

- for (i = 0; i < CHECK_LOOPS; i++) {
+ for (i = 0; i < check_loops; i++) {
init();
- for (j = 0; j < NODES; j++) {
+ for (j = 0; j < nnodes; j++) {
check(j);
insert(nodes + j, &root);
}
- for (j = 0; j < NODES; j++) {
- check(NODES - j);
+ for (j = 0; j < nnodes; j++) {
+ check(nnodes - j);
erase(nodes + j, &root);
}
check(0);
@@ -216,32 +227,34 @@ static int __init rbtree_test_init(void)

time1 = get_cycles();

- for (i = 0; i < PERF_LOOPS; i++) {
- for (j = 0; j < NODES; j++)
+ for (i = 0; i < perf_loops; i++) {
+ for (j = 0; j < nnodes; j++)
insert_augmented(nodes + j, &root);
- for (j = 0; j < NODES; j++)
+ for (j = 0; j < nnodes; j++)
erase_augmented(nodes + j, &root);
}

time2 = get_cycles();
time = time2 - time1;

- time = div_u64(time, PERF_LOOPS);
+ time = div_u64(time, perf_loops);
printk(" -> %llu cycles\n", (unsigned long long)time);

- for (i = 0; i < CHECK_LOOPS; i++) {
+ for (i = 0; i < check_loops; i++) {
init();
- for (j = 0; j < NODES; j++) {
+ for (j = 0; j < nnodes; j++) {
check_augmented(j);
insert_augmented(nodes + j, &root);
}
- for (j = 0; j < NODES; j++) {
- check_augmented(NODES - j);
+ for (j = 0; j < nnodes; j++) {
+ check_augmented(nnodes - j);
erase_augmented(nodes + j, &root);
}
check_augmented(0);
}

+ kfree(nodes);
+
return -EAGAIN; /* Fail will directly unload the module */
}

--
2.19.1