This is a note to let you know that I've just added the patch titled

test_rhashtable: add test case for rhltable with duplicate objects

to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: test_rhashtable-add-test-case-for-rhltable-with-duplicate-objects.patch and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Wed Mar 28 18:37:51 CEST 2018

From: Paul Blakey paulb@mellanox.com Date: Sun, 4 Mar 2018 17:29:49 +0200 Subject: test_rhashtable: add test case for rhltable with duplicate objects

From: Paul Blakey paulb@mellanox.com

[ Upstream commit 499ac3b60f657dae82055fc81c7b01e6242ac9bc ]

Tries to insert duplicates in the middle of bucket's chain: bucket 1: [[val 21 (tid=1)]] -> [[ val 1 (tid=2), val 1 (tid=0) ]]

Reuses tid to distinguish the elements insertion order.

Signed-off-by: Paul Blakey paulb@mellanox.com Acked-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- lib/test_rhashtable.c | 134 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 134 insertions(+)

--- a/lib/test_rhashtable.c +++ b/lib/test_rhashtable.c @@ -79,6 +79,21 @@ struct thread_data { struct test_obj *objs; };

+static u32 my_hashfn(const void *data, u32 len, u32 seed) +{ + const struct test_obj_rhl *obj = data; + + return (obj->value.id % 10) << RHT_HASH_RESERVED_SPACE; +} + +static int my_cmpfn(struct rhashtable_compare_arg *arg, const void *obj) +{ + const struct test_obj_rhl *test_obj = obj; + const struct test_obj_val *val = arg->key; + + return test_obj->value.id - val->id; +} + static struct rhashtable_params test_rht_params = { .head_offset = offsetof(struct test_obj, node), .key_offset = offsetof(struct test_obj, value), @@ -87,6 +102,17 @@ static struct rhashtable_params test_rht .nulls_base = (3U << RHT_BASE_SHIFT), };

+static struct rhashtable_params test_rht_params_dup = { + .head_offset = offsetof(struct test_obj_rhl, list_node), + .key_offset = offsetof(struct test_obj_rhl, value), + .key_len = sizeof(struct test_obj_val), + .hashfn = jhash, + .obj_hashfn = my_hashfn, + .obj_cmpfn = my_cmpfn, + .nelem_hint = 128, + .automatic_shrinking = false, +}; + static struct semaphore prestart_sem; static struct semaphore startup_sem = __SEMAPHORE_INITIALIZER(startup_sem, 0);

@@ -469,6 +495,112 @@ static int __init test_rhashtable_max(st return err; }

+static unsigned int __init print_ht(struct rhltable *rhlt) +{ + struct rhashtable *ht; + const struct bucket_table *tbl; + char buff[512] = ""; + unsigned int i, cnt = 0; + + ht = &rhlt->ht; + tbl = rht_dereference(ht->tbl, ht); + for (i = 0; i < tbl->size; i++) { + struct rhash_head *pos, *next; + struct test_obj_rhl *p; + + pos = rht_dereference(tbl->buckets[i], ht); + next = !rht_is_a_nulls(pos) ? rht_dereference(pos->next, ht) : NULL; + + if (!rht_is_a_nulls(pos)) { + sprintf(buff, "%s\nbucket[%d] -> ", buff, i); + } + + while (!rht_is_a_nulls(pos)) { + struct rhlist_head *list = container_of(pos, struct rhlist_head, rhead); + sprintf(buff, "%s[[", buff); + do { + pos = &list->rhead; + list = rht_dereference(list->next, ht); + p = rht_obj(ht, pos); + + sprintf(buff, "%s val %d (tid=%d)%s", buff, p->value.id, p->value.tid, + list? ", " : " "); + cnt++; + } while (list); + + pos = next, + next = !rht_is_a_nulls(pos) ? + rht_dereference(pos->next, ht) : NULL; + + sprintf(buff, "%s]]%s", buff, !rht_is_a_nulls(pos) ? " -> " : ""); + } + } + printk(KERN_ERR "\n---- ht: ----%s\n-------------\n", buff); + + return cnt; +} + +static int __init test_insert_dup(struct test_obj_rhl *rhl_test_objects, + int cnt, bool slow) +{ + struct rhltable rhlt; + unsigned int i, ret; + const char *key; + int err = 0; + + err = rhltable_init(&rhlt, &test_rht_params_dup); + if (WARN_ON(err)) + return err; + + for (i = 0; i < cnt; i++) { + rhl_test_objects[i].value.tid = i; + key = rht_obj(&rhlt.ht, &rhl_test_objects[i].list_node.rhead); + key += test_rht_params_dup.key_offset; + + if (slow) { + err = PTR_ERR(rhashtable_insert_slow(&rhlt.ht, key, + &rhl_test_objects[i].list_node.rhead)); + if (err == -EAGAIN) + err = 0; + } else + err = rhltable_insert(&rhlt, + &rhl_test_objects[i].list_node, + test_rht_params_dup); + if (WARN(err, "error %d on element %d/%d (%s)\n", err, i, cnt, slow? "slow" : "fast")) + goto skip_print; + } + + ret = print_ht(&rhlt); + WARN(ret != cnt, "missing rhltable elements (%d != %d, %s)\n", ret, cnt, slow? "slow" : "fast"); + +skip_print: + rhltable_destroy(&rhlt); + + return 0; +} + +static int __init test_insert_duplicates_run(void) +{ + struct test_obj_rhl rhl_test_objects[3] = {}; + + pr_info("test inserting duplicates\n"); + + /* two different values that map to same bucket */ + rhl_test_objects[0].value.id = 1; + rhl_test_objects[1].value.id = 21; + + /* and another duplicate with same as [0] value + * which will be second on the bucket list */ + rhl_test_objects[2].value.id = rhl_test_objects[0].value.id; + + test_insert_dup(rhl_test_objects, 2, false); + test_insert_dup(rhl_test_objects, 3, false); + test_insert_dup(rhl_test_objects, 2, true); + test_insert_dup(rhl_test_objects, 3, true); + + return 0; +} + static int thread_lookup_test(struct thread_data *tdata) { unsigned int entries = tdata->entries; @@ -617,6 +749,8 @@ static int __init test_rht_init(void) do_div(total_time, runs); pr_info("Average test time: %llu\n", total_time);

+ test_insert_duplicates_run(); + if (!tcount) return 0;

Patches currently in stable-queue which might be from paulb@mellanox.com are

queue-4.15/rhashtable-fix-rhlist-duplicates-insertion.patch queue-4.15/test_rhashtable-add-test-case-for-rhltable-with-duplicate-objects.patch