summaryrefslogtreecommitdiff
path: root/lib
diff options
context:
space:
mode:
Diffstat (limited to 'lib')
-rw-r--r--lib/Kconfig.debug23
-rw-r--r--lib/Makefile1
-rw-r--r--lib/netdev-notifier-error-inject.c55
-rw-r--r--lib/rhashtable.c3
-rw-r--r--lib/test_rhashtable.c76
5 files changed, 129 insertions, 29 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 8c15b29d5adc..0d76ecce27bb 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1484,6 +1484,29 @@ config OF_RECONFIG_NOTIFIER_ERROR_INJECT
If unsure, say N.
+config NETDEV_NOTIFIER_ERROR_INJECT
+ tristate "Netdev notifier error injection module"
+ depends on NET && NOTIFIER_ERROR_INJECTION
+ help
+ This option provides the ability to inject artificial errors to
+ netdevice notifier chain callbacks. It is controlled through debugfs
+ interface /sys/kernel/debug/notifier-error-inject/netdev
+
+ If the notifier call chain should be failed with some events
+ notified, write the error code to "actions/<notifier event>/error".
+
+ Example: Inject netdevice mtu change error (-22 = -EINVAL)
+
+ # cd /sys/kernel/debug/notifier-error-inject/netdev
+ # echo -22 > actions/NETDEV_CHANGEMTU/error
+ # ip link set eth0 mtu 1024
+ RTNETLINK answers: Invalid argument
+
+ To compile this code as a module, choose M here: the module will
+ be called netdev-notifier-error-inject.
+
+ If unsure, say N.
+
config FAULT_INJECTION
bool "Fault-injection framework"
depends on DEBUG_KERNEL
diff --git a/lib/Makefile b/lib/Makefile
index 7f1de26613d2..180dd4d0dd41 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -120,6 +120,7 @@ obj-$(CONFIG_FAULT_INJECTION) += fault-inject.o
obj-$(CONFIG_NOTIFIER_ERROR_INJECTION) += notifier-error-inject.o
obj-$(CONFIG_CPU_NOTIFIER_ERROR_INJECT) += cpu-notifier-error-inject.o
obj-$(CONFIG_PM_NOTIFIER_ERROR_INJECT) += pm-notifier-error-inject.o
+obj-$(CONFIG_NETDEV_NOTIFIER_ERROR_INJECT) += netdev-notifier-error-inject.o
obj-$(CONFIG_MEMORY_NOTIFIER_ERROR_INJECT) += memory-notifier-error-inject.o
obj-$(CONFIG_OF_RECONFIG_NOTIFIER_ERROR_INJECT) += \
of-reconfig-notifier-error-inject.o
diff --git a/lib/netdev-notifier-error-inject.c b/lib/netdev-notifier-error-inject.c
new file mode 100644
index 000000000000..13e9c62e216f
--- /dev/null
+++ b/lib/netdev-notifier-error-inject.c
@@ -0,0 +1,55 @@
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+
+#include "notifier-error-inject.h"
+
+static int priority;
+module_param(priority, int, 0);
+MODULE_PARM_DESC(priority, "specify netdevice notifier priority");
+
+static struct notifier_err_inject netdev_notifier_err_inject = {
+ .actions = {
+ { NOTIFIER_ERR_INJECT_ACTION(NETDEV_REGISTER) },
+ { NOTIFIER_ERR_INJECT_ACTION(NETDEV_CHANGEMTU) },
+ { NOTIFIER_ERR_INJECT_ACTION(NETDEV_CHANGENAME) },
+ { NOTIFIER_ERR_INJECT_ACTION(NETDEV_PRE_UP) },
+ { NOTIFIER_ERR_INJECT_ACTION(NETDEV_PRE_TYPE_CHANGE) },
+ { NOTIFIER_ERR_INJECT_ACTION(NETDEV_POST_INIT) },
+ { NOTIFIER_ERR_INJECT_ACTION(NETDEV_PRECHANGEMTU) },
+ { NOTIFIER_ERR_INJECT_ACTION(NETDEV_PRECHANGEUPPER) },
+ { NOTIFIER_ERR_INJECT_ACTION(NETDEV_CHANGEUPPER) },
+ {}
+ }
+};
+
+static struct dentry *dir;
+
+static int netdev_err_inject_init(void)
+{
+ int err;
+
+ dir = notifier_err_inject_init("netdev", notifier_err_inject_dir,
+ &netdev_notifier_err_inject, priority);
+ if (IS_ERR(dir))
+ return PTR_ERR(dir);
+
+ err = register_netdevice_notifier(&netdev_notifier_err_inject.nb);
+ if (err)
+ debugfs_remove_recursive(dir);
+
+ return err;
+}
+
+static void netdev_err_inject_exit(void)
+{
+ unregister_netdevice_notifier(&netdev_notifier_err_inject.nb);
+ debugfs_remove_recursive(dir);
+}
+
+module_init(netdev_err_inject_init);
+module_exit(netdev_err_inject_exit);
+
+MODULE_DESCRIPTION("Netdevice notifier error injection module");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Nikolay Aleksandrov <razor@blackwall.org>");
diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index eb9240c458fa..1c149e9a5cd5 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -231,9 +231,6 @@ static int rhashtable_rehash_attach(struct rhashtable *ht,
*/
rcu_assign_pointer(old_tbl->future_tbl, new_tbl);
- /* Ensure the new table is visible to readers. */
- smp_wmb();
-
spin_unlock_bh(old_tbl->locks);
return 0;
diff --git a/lib/test_rhashtable.c b/lib/test_rhashtable.c
index 8c1ad1ced72c..270bf7289b1e 100644
--- a/lib/test_rhashtable.c
+++ b/lib/test_rhashtable.c
@@ -36,9 +36,9 @@ static int runs = 4;
module_param(runs, int, 0);
MODULE_PARM_DESC(runs, "Number of test runs per variant (default: 4)");
-static int max_size = 65536;
+static int max_size = 0;
module_param(max_size, int, 0);
-MODULE_PARM_DESC(runs, "Maximum table size (default: 65536)");
+MODULE_PARM_DESC(runs, "Maximum table size (default: calculated)");
static bool shrinking = false;
module_param(shrinking, bool, 0);
@@ -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;
@@ -76,6 +80,28 @@ static struct rhashtable_params test_rht_params = {
static struct semaphore prestart_sem;
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, 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;
+}
+
static int __init test_rht_lookup(struct rhashtable *ht)
{
unsigned int i;
@@ -157,7 +183,7 @@ static s64 __init test_rhashtable(struct rhashtable *ht)
{
struct test_obj *obj;
int err;
- unsigned int i, insert_fails = 0;
+ unsigned int i, insert_retries = 0;
s64 start, end;
/*
@@ -170,22 +196,16 @@ static s64 __init test_rhashtable(struct rhashtable *ht)
struct test_obj *obj = &array[i];
obj->value = i * 2;
-
- err = rhashtable_insert_fast(ht, &obj->node, test_rht_params);
- if (err == -ENOMEM || err == -EBUSY) {
- /* Mark failed inserts but continue */
- obj->value = TEST_INSERT_FAIL;
- insert_fails++;
- } else if (err) {
+ err = insert_retry(ht, &obj->node, test_rht_params);
+ if (err > 0)
+ insert_retries += err;
+ else if (err)
return err;
- }
-
- cond_resched();
}
- if (insert_fails)
- pr_info(" %u insertions failed due to memory pressure\n",
- insert_fails);
+ if (insert_retries)
+ pr_info(" %u insertions retried due to memory pressure\n",
+ insert_retries);
test_bucket_stats(ht);
rcu_read_lock();
@@ -236,13 +256,15 @@ static int thread_lookup_test(struct thread_data *tdata)
obj->value, key);
err++;
}
+
+ cond_resched();
}
return err;
}
static int threadfunc(void *data)
{
- int i, step, err = 0, insert_fails = 0;
+ int i, step, err = 0, insert_retries = 0;
struct thread_data *tdata = data;
up(&prestart_sem);
@@ -251,20 +273,18 @@ static int threadfunc(void *data)
for (i = 0; i < entries; i++) {
tdata->objs[i].value = (tdata->id << 16) | i;
- err = rhashtable_insert_fast(&ht, &tdata->objs[i].node,
- test_rht_params);
- if (err == -ENOMEM || err == -EBUSY) {
- tdata->objs[i].value = TEST_INSERT_FAIL;
- insert_fails++;
+ err = insert_retry(&ht, &tdata->objs[i].node, test_rht_params);
+ if (err > 0) {
+ insert_retries += err;
} else if (err) {
pr_err(" thread[%d]: rhashtable_insert_fast failed\n",
tdata->id);
goto out;
}
}
- if (insert_fails)
- pr_info(" thread[%d]: %d insert failures\n",
- tdata->id, insert_fails);
+ if (insert_retries)
+ pr_info(" thread[%d]: %u insertions retried due to memory pressure\n",
+ tdata->id, insert_retries);
err = thread_lookup_test(tdata);
if (err) {
@@ -285,6 +305,8 @@ static int threadfunc(void *data)
goto out;
}
tdata->objs[i].value = TEST_INSERT_FAIL;
+
+ cond_resched();
}
err = thread_lookup_test(tdata);
if (err) {
@@ -311,7 +333,7 @@ static int __init test_rht_init(void)
entries = min(entries, MAX_ENTRIES);
test_rht_params.automatic_shrinking = shrinking;
- test_rht_params.max_size = max_size;
+ test_rht_params.max_size = max_size ? : roundup_pow_of_two(entries);
test_rht_params.nelem_hint = size;
pr_info("Running rhashtable test nelem=%d, max_size=%d, shrinking=%d\n",
@@ -357,6 +379,8 @@ static int __init test_rht_init(void)
return -ENOMEM;
}
+ test_rht_params.max_size = max_size ? :
+ roundup_pow_of_two(tcount * entries);
err = rhashtable_init(&ht, &test_rht_params);
if (err < 0) {
pr_warn("Test failed: Unable to initialize hashtable: %d\n",
generated by cgit v1.2.3 (git 2.39.0) at 2024-09-01 15:05:53 +0300