Commit d662e037 authored by Phil Sutter's avatar Phil Sutter Committed by David S. Miller
Browse files

rhashtable-test: allow to retry even if -ENOMEM was returned 



This is rather a hack to expose the current issue with rhashtable to
under high pressure sometimes return -ENOMEM even though system memory
is not exhausted and a consecutive insert may succeed.

Signed-off-by: default avatarPhil Sutter <phil@nwl.cc>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 95e435af

lib/test_rhashtable.c

+13 −1
Original line number Diff line number Diff line
@@ -52,6 +52,10 @@ static int tcount = 10; 
module_param(tcount, int, 0);

MODULE_PARM_DESC(tcount, "Number of threads to spawn (default: 10)");



static bool enomem_retry = false;

module_param(enomem_retry, bool, 0);

MODULE_PARM_DESC(enomem_retry, "Retry insert even if -ENOMEM was returned (default: off)");



struct test_obj {

	int			value;

	struct rhash_head	node;
@@ -79,14 +83,22 @@ static struct semaphore startup_sem = __SEMAPHORE_INITIALIZER(startup_sem, 0); 
static int insert_retry(struct rhashtable *ht, struct rhash_head *obj,

                        const struct rhashtable_params params)

{

	int err, retries = -1;

	int err, retries = -1, enomem_retries = 0;



	do {

		retries++;

		cond_resched();

		err = rhashtable_insert_fast(ht, obj, params);

		if (err == -ENOMEM && enomem_retry) {

			enomem_retries++;

			err = -EBUSY;

		}

	} while (err == -EBUSY);



	if (enomem_retries)

		pr_info(" %u insertions retried after -ENOMEM\n",

			enomem_retries);



	return err ? : retries;

}