diff mbox series

rhashtable: make test actually random

Message ID 12102372.O9o76ZdvQC@eto.sf-tec.de (mailing list archive)
State Not Applicable
Headers show
Series rhashtable: make test actually random | expand

Checks

Context Check Description
netdev/tree_selection success Not a local patch

Commit Message

Rolf Eike Beer Oct. 21, 2022, 1:45 p.m. UTC 
The "random rhlist add/delete operations" actually wasn't very random, as all
cases tested the same bit. Since the later parts of this loop depend on the
first case execute this unconditionally, and then test on different bits for the
remaining tests. While at it only request as much random bits as are actually
used.

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
---
 lib/test_rhashtable.c | 58 ++++++++++++++++---------------------------
 1 file changed, 22 insertions(+), 36 deletions(-)
diff mbox series

Patch

diff --git a/lib/test_rhashtable.c b/lib/test_rhashtable.c
index b358a74ed7ed..f2ba5787055a 100644
--- a/lib/test_rhashtable.c
+++ b/lib/test_rhashtable.c
@@ -369,18 +369,10 @@  static int __init test_rhltable(unsigned int entries)
 	pr_info("test %d random rhlist add/delete operations\n", entries);
 	for (j = 0; j < entries; j++) {
 		u32 i = prandom_u32_max(entries);
-		u32 prand = get_random_u32();
+		u32 prand = prandom_u32_max(4);
 
 		cond_resched();
 
-		if (prand == 0)
-			prand = get_random_u32();
-
-		if (prand & 1) {
-			prand >>= 1;
-			continue;
-		}
-
 		err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 		if (test_bit(i, obj_in_table)) {
 			clear_bit(i, obj_in_table);
@@ -393,35 +385,29 @@  static int __init test_rhltable(unsigned int entries)
 		}
 
 		if (prand & 1) {
-			prand >>= 1;
-			continue;
-		}
-
-		err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
-		if (err == 0) {
-			if (WARN(test_and_set_bit(i, obj_in_table), "succeeded to insert same object %d", i))
-				continue;
-		} else {
-			if (WARN(!test_bit(i, obj_in_table), "failed to insert object %d", i))
-				continue;
-		}
-
-		if (prand & 1) {
-			prand >>= 1;
-			continue;
+			err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
+			if (err == 0) {
+				if (WARN(test_and_set_bit(i, obj_in_table), "succeeded to insert same object %d", i))
+					continue;
+			} else {
+				if (WARN(!test_bit(i, obj_in_table), "failed to insert object %d", i))
+					continue;
+			}
 		}
 
-		i = prandom_u32_max(entries);
-		if (test_bit(i, obj_in_table)) {
-			err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
-			WARN(err, "cannot remove element at slot %d", i);
-			if (err == 0)
-				clear_bit(i, obj_in_table);
-		} else {
-			err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
-			WARN(err, "failed to insert object %d", i);
-			if (err == 0)
-				set_bit(i, obj_in_table);
+		if (prand & 2) {
+			i = prandom_u32_max(entries);
+			if (test_bit(i, obj_in_table)) {
+				err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
+				WARN(err, "cannot remove element at slot %d", i);
+				if (err == 0)
+					clear_bit(i, obj_in_table);
+			} else {
+				err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
+				WARN(err, "failed to insert object %d", i);
+				if (err == 0)
+					set_bit(i, obj_in_table);
+			}
 		}
 	}