lib/rbtree_test.c: make input module parameters

Allows for more flexible debugging.

Link: http://lkml.kernel.org/r/20170719014603.19029-5-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files 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 */
 }