@@ -102,6 +102,9 @@ Refer to rte_kni_common.h in the DPDK source code for more details.
The physical addresses will be re-mapped into the kernel address space and stored in separate KNI contexts.
+The affinity of kernel RX thread (both single and multi-threaded modes) is controlled by force_bind and
+core_id config parameters.
+
The KNI interfaces can be deleted by a DPDK application dynamically after being created.
Furthermore, all those KNI interfaces not deleted will be deleted on the release operation
of the miscellaneous device (when the DPDK application is closed).
@@ -30,6 +30,7 @@
#include <linux/pci.h>
#include <linux/kthread.h>
#include <linux/rwsem.h>
+#include <linux/mutex.h>
#include <linux/nsproxy.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
@@ -100,6 +101,7 @@ static int kni_net_id;
struct kni_net {
unsigned long device_in_use; /* device in use flag */
+ struct mutex kni_kthread_lock;
struct task_struct *kni_kthread;
struct rw_semaphore kni_list_lock;
struct list_head kni_list_head;
@@ -109,11 +111,12 @@ static int __net_init kni_init_net(struct net *net)
{
#ifdef HAVE_SIMPLIFIED_PERNET_OPERATIONS
struct kni_net *knet = net_generic(net, kni_net_id);
+ memset(knet, 0, sizeof(*knet));
#else
struct kni_net *knet;
int ret;
- knet = kmalloc(sizeof(struct kni_net), GFP_KERNEL);
+ knet = kzalloc(sizeof(struct kni_net), GFP_KERNEL);
if (!knet) {
ret = -ENOMEM;
return ret;
@@ -123,6 +126,8 @@ static int __net_init kni_init_net(struct net *net)
/* Clear the bit of device in use */
clear_bit(KNI_DEV_IN_USE_BIT_NUM, &knet->device_in_use);
+ mutex_init(&knet->kni_kthread_lock);
+
init_rwsem(&knet->kni_list_lock);
INIT_LIST_HEAD(&knet->kni_list_head);
@@ -139,9 +144,9 @@ static int __net_init kni_init_net(struct net *net)
static void __net_exit kni_exit_net(struct net *net)
{
-#ifndef HAVE_SIMPLIFIED_PERNET_OPERATIONS
struct kni_net *knet = net_generic(net, kni_net_id);
-
+ mutex_destroy(&knet->kni_kthread_lock);
+#ifndef HAVE_SIMPLIFIED_PERNET_OPERATIONS
kfree(knet);
#endif
}
@@ -167,6 +172,11 @@ kni_init(void)
return -EINVAL;
}
+ if (multiple_kthread_on == 0)
+ KNI_PRINT("Single kernel thread for all KNI devices\n");
+ else
+ KNI_PRINT("Multiple kernel thread mode enabled\n");
+
#ifdef HAVE_SIMPLIFIED_PERNET_OPERATIONS
rc = register_pernet_subsys(&kni_net_ops);
#else
@@ -235,19 +245,6 @@ kni_open(struct inode *inode, struct file *file)
if (test_and_set_bit(KNI_DEV_IN_USE_BIT_NUM, &knet->device_in_use))
return -EBUSY;
- /* Create kernel thread for single mode */
- if (multiple_kthread_on == 0) {
- KNI_PRINT("Single kernel thread for all KNI devices\n");
- /* Create kernel thread for RX */
- knet->kni_kthread = kthread_run(kni_thread_single, (void *)knet,
- "kni_single");
- if (IS_ERR(knet->kni_kthread)) {
- KNI_ERR("Unable to create kernel threaed\n");
- return PTR_ERR(knet->kni_kthread);
- }
- } else
- KNI_PRINT("Multiple kernel thread mode enabled\n");
-
file->private_data = get_net(net);
KNI_PRINT("/dev/kni opened\n");
@@ -263,9 +260,13 @@ kni_release(struct inode *inode, struct file *file)
/* Stop kernel thread for single mode */
if (multiple_kthread_on == 0) {
+ mutex_lock(&knet->kni_kthread_lock);
/* Stop kernel thread */
- kthread_stop(knet->kni_kthread);
- knet->kni_kthread = NULL;
+ if (knet->kni_kthread != NULL) {
+ kthread_stop(knet->kni_kthread);
+ knet->kni_kthread = NULL;
+ }
+ mutex_unlock(&knet->kni_kthread_lock);
}
down_write(&knet->kni_list_lock);
@@ -390,6 +391,47 @@ kni_check_param(struct kni_dev *kni, struct rte_kni_device_info *dev)
}
static int
+kni_run_thread(struct kni_net *knet, struct kni_dev *kni, uint8_t force_bind)
+{
+ /**
+ * Create a new kernel thread for multiple mode, set its core affinity,
+ * and finally wake it up.
+ */
+ if (multiple_kthread_on) {
+ kni->pthread = kthread_create(kni_thread_multiple,
+ (void *)kni, "kni_%s", kni->name);
+ if (IS_ERR(kni->pthread)) {
+ kni_dev_remove(kni);
+ return -ECANCELED;
+ }
+
+ if (force_bind)
+ kthread_bind(kni->pthread, kni->core_id);
+ wake_up_process(kni->pthread);
+ } else {
+ mutex_lock(&knet->kni_kthread_lock);
+
+ if (knet->kni_kthread == NULL) {
+ knet->kni_kthread = kthread_create(kni_thread_single,
+ (void *)knet, "kni_single");
+ if (IS_ERR(knet->kni_kthread)) {
+ mutex_unlock(&knet->kni_kthread_lock);
+ kni_dev_remove(kni);
+ return -ECANCELED;
+ }
+
+ if (force_bind)
+ kthread_bind(knet->kni_kthread, kni->core_id);
+ wake_up_process(knet->kni_kthread);
+ }
+
+ mutex_unlock(&knet->kni_kthread_lock);
+ }
+
+ return 0;
+}
+
+static int
kni_ioctl_create(struct net *net,
unsigned int ioctl_num, unsigned long ioctl_param)
{
@@ -415,11 +457,9 @@ kni_ioctl_create(struct net *net,
}
/**
- * Check if the cpu core id is valid for binding,
- * for multiple kernel thread mode.
+ * Check if the cpu core id is valid for binding.
*/
- if (multiple_kthread_on && dev_info.force_bind &&
- !cpu_online(dev_info.core_id)) {
+ if (dev_info.force_bind && !cpu_online(dev_info.core_id)) {
KNI_ERR("cpu %u is not online\n", dev_info.core_id);
return -EINVAL;
}
@@ -566,22 +606,9 @@ kni_ioctl_create(struct net *net,
kni_vhost_init(kni);
#endif
- /**
- * Create a new kernel thread for multiple mode, set its core affinity,
- * and finally wake it up.
- */
- if (multiple_kthread_on) {
- kni->pthread = kthread_create(kni_thread_multiple,
- (void *)kni,
- "kni_%s", kni->name);
- if (IS_ERR(kni->pthread)) {
- kni_dev_remove(kni);
- return -ECANCELED;
- }
- if (dev_info.force_bind)
- kthread_bind(kni->pthread, kni->core_id);
- wake_up_process(kni->pthread);
- }
+ ret = kni_run_thread(knet, kni, dev_info.force_bind);
+ if (ret != 0)
+ return ret;
down_write(&knet->kni_list_lock);
list_add(&kni->list, &knet->kni_list_head);