kni: allow multiple threads

In this new mode, each KNI device has its own kernel thread for Rx.
The core affinity is configurable.

Signed-off-by: Intel

diff --git a/lib/librte_eal/linuxapp/kni/kni_dev.h b/lib/librte_eal/linuxapp/kni/kni_dev.h
index cb13888..1d7f066 100644 (file)
--- a/lib/librte_eal/linuxapp/kni/kni_dev.h
+++ b/lib/librte_eal/linuxapp/kni/kni_dev.h
@@ -33,7 +33,7 @@
 #include <linux/list.h>
 
 #include <exec-env/rte_kni_common.h>
-#define KNI_KTHREAD_RESCHEDULE_INTERVAL 10 /* us */
+#define KNI_KTHREAD_RESCHEDULE_INTERVAL 5 /* us */
 
 /**
  * A structure describing the private information for a kni device.
@@ -46,7 +46,9 @@ struct kni_dev {
        struct net_device_stats stats;
        int status;
        uint16_t group_id;           /* Group ID of a group of KNI devices */
+       unsigned core_id;            /* Core ID to bind */
        char name[RTE_KNI_NAMESIZE]; /* Network device name */
+       struct task_struct *pthread;
 
        /* wait queue for req/resp */
        wait_queue_head_t wq;

diff --git a/lib/librte_eal/linuxapp/kni/kni_misc.c b/lib/librte_eal/linuxapp/kni/kni_misc.c
index 9adf697..79ab1f9 100644 (file)
--- a/lib/librte_eal/linuxapp/kni/kni_misc.c
+++ b/lib/librte_eal/linuxapp/kni/kni_misc.c
@@ -58,9 +58,14 @@ static int kni_ioctl(struct inode *inode, unsigned int ioctl_num,
                                        unsigned long ioctl_param);
 static int kni_compat_ioctl(struct inode *inode, unsigned int ioctl_num,
                                                unsigned long ioctl_param);
+static int kni_dev_remove(struct kni_dev *dev);
 
-/* kni kernel thread for rx */
-static int kni_thread(void *unused);
+static int __init kni_parse_kthread_mode(void);
+
+/* KNI processing for single kernel thread mode */
+static int kni_thread_single(void *unused);
+/* KNI processing for multiple kernel thread mode */
+static int kni_thread_multiple(void *param);
 
 static struct file_operations kni_fops = {
        .owner = THIS_MODULE,
@@ -79,6 +84,10 @@ static struct miscdevice kni_misc = {
 /* loopback mode */
 static char *lo_mode = NULL;
 
+/* Kernel thread mode */
+static char *kthread_mode = NULL;
+static unsigned multiple_kthread_on = 0;
+
 #define KNI_DEV_IN_USE_BIT_NUM 0 /* Bit number for device in use */
 
 static volatile unsigned long device_in_use; /* device in use flag */
@@ -95,9 +104,14 @@ kni_init(void)
 {
        KNI_PRINT("######## DPDK kni module loading ########\n");
 
+       if (kni_parse_kthread_mode() < 0) {
+               KNI_ERR("Invalid parameter for kthread_mode\n");
+               return -EINVAL;
+       }
+
        if (misc_register(&kni_misc) != 0) {
                KNI_ERR("Misc registration failed\n");
-               return 1;
+               return -EPERM;
        }
 
        /* Clear the bit of device in use */
@@ -118,6 +132,22 @@ kni_exit(void)
        KNI_PRINT("####### DPDK kni module unloaded  #######\n");
 }
 
+static int __init
+kni_parse_kthread_mode(void)
+{
+       if (!kthread_mode)
+               return 0;
+
+       if (strcmp(kthread_mode, "single") == 0)
+               return 0;
+       else if (strcmp(kthread_mode, "multiple") == 0)
+               multiple_kthread_on = 1;
+       else
+               return -1;
+
+       return 0;
+}
+
 static int
 kni_open(struct inode *inode, struct file *file)
 {
@@ -125,12 +155,18 @@ kni_open(struct inode *inode, struct file *file)
        if (test_and_set_bit(KNI_DEV_IN_USE_BIT_NUM, &device_in_use))
                return -EBUSY;
 
-       /* Create kernel thread for RX */
-       kni_kthread = kthread_run(kni_thread, NULL, "kni_thread");
-       if (IS_ERR(kni_kthread)) {
-               KNI_ERR("Unable to create kernel threaed\n");
-               return PTR_ERR(kni_kthread);
-       }
+       /* 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 */
+               kni_kthread = kthread_run(kni_thread_single, NULL,
+                                               "kni_single");
+               if (IS_ERR(kni_kthread)) {
+                       KNI_ERR("Unable to create kernel threaed\n");
+                       return PTR_ERR(kni_kthread);
+               }
+       } else
+               KNI_PRINT("Multiple kernel thread mode enabled\n");
 
        KNI_PRINT("/dev/kni opened\n");
 
@@ -142,27 +178,22 @@ kni_release(struct inode *inode, struct file *file)
 {
        struct kni_dev *dev, *n;
 
-       /* Stop kernel thread */
-       kthread_stop(kni_kthread);
-       kni_kthread = NULL;
+       /* Stop kernel thread for single mode */
+       if (multiple_kthread_on == 0) {
+               /* Stop kernel thread */
+               kthread_stop(kni_kthread);
+               kni_kthread = NULL;
+       }
 
        down_write(&kni_list_lock);
        list_for_each_entry_safe(dev, n, &kni_list_head, list) {
-               /* Call the remove part to restore pci dev */
-               switch (dev->device_id) {
-               #define RTE_PCI_DEV_ID_DECL_IGB(vend, dev) case (dev):
-               #include <rte_pci_dev_ids.h>
-                       igb_kni_remove(dev->pci_dev);
-                       break;
-               #define RTE_PCI_DEV_ID_DECL_IXGBE(vend, dev) case (dev):
-               #include <rte_pci_dev_ids.h>
-                       ixgbe_kni_remove(dev->pci_dev);
-                       break;
-               default:
-                       break;
+               /* Stop kernel thread for multiple mode */
+               if (multiple_kthread_on && dev->pthread != NULL) {
+                       kthread_stop(dev->pthread);
+                       dev->pthread = NULL;
                }
-               unregister_netdev(dev->net_dev);
-               free_netdev(dev->net_dev);
+
+               kni_dev_remove(dev);
                list_del(&dev->list);
        }
        up_write(&kni_list_lock);
@@ -176,7 +207,7 @@ kni_release(struct inode *inode, struct file *file)
 }
 
 static int
-kni_thread(void *unused)
+kni_thread_single(void *unused)
 {
        int j;
        struct kni_dev *dev, *n;
@@ -199,6 +230,51 @@ kni_thread(void *unused)
        return 0;
 }
 
+static int
+kni_thread_multiple(void *param)
+{
+       int j;
+       struct kni_dev *dev = (struct kni_dev *)param;
+
+       while (!kthread_should_stop()) {
+               for (j = 0; j < KNI_RX_LOOP_NUM; j++) {
+                       kni_net_rx(dev);
+                       kni_net_poll_resp(dev);
+               }
+               schedule_timeout_interruptible(usecs_to_jiffies( \
+                               KNI_KTHREAD_RESCHEDULE_INTERVAL));
+       }
+
+       return 0;
+}
+
+static int
+kni_dev_remove(struct kni_dev *dev)
+{
+       if (!dev)
+               return -ENODEV;
+
+       switch (dev->device_id) {
+       #define RTE_PCI_DEV_ID_DECL_IGB(vend, dev) case (dev):
+       #include <rte_pci_dev_ids.h>
+               igb_kni_remove(dev->pci_dev);
+               break;
+       #define RTE_PCI_DEV_ID_DECL_IXGBE(vend, dev) case (dev):
+       #include <rte_pci_dev_ids.h>
+               ixgbe_kni_remove(dev->pci_dev);
+               break;
+       default:
+               break;
+       }
+
+       if (dev->net_dev) {
+               unregister_netdev(dev->net_dev);
+               free_netdev(dev->net_dev);
+       }
+
+       return 0;
+}
+
 static int
 kni_check_param(struct kni_dev *kni, struct rte_kni_device_info *dev)
 {
@@ -237,6 +313,16 @@ kni_ioctl_create(unsigned int ioctl_num, unsigned long ioctl_param)
                return -EIO;
        }
 
+       /**
+        * Check if the cpu core id is valid for binding,
+        * for multiple kernel thread mode.
+        */
+       if (multiple_kthread_on && dev_info.force_bind &&
+                               !cpu_online(dev_info.core_id)) {
+               KNI_ERR("cpu %u is not online\n", dev_info.core_id);
+               return -EINVAL;
+       }
+
        /* Check if it has been created */
        down_read(&kni_list_lock);
        list_for_each_entry_safe(dev, n, &kni_list_head, list) {
@@ -258,6 +344,7 @@ kni_ioctl_create(unsigned int ioctl_num, unsigned long ioctl_param)
 
        kni->net_dev = net_dev;
        kni->group_id = dev_info.group_id;
+       kni->core_id = dev_info.core_id;
        strncpy(kni->name, dev_info.name, RTE_KNI_NAMESIZE);
 
        /* Translate user space info into kernel space info */
@@ -352,10 +439,27 @@ kni_ioctl_create(unsigned int ioctl_num, unsigned long ioctl_param)
        if (ret) {
                KNI_ERR("error %i registering device \"%s\"\n",
                                        ret, dev_info.name);
-               free_netdev(net_dev);
+               kni_dev_remove(kni);
                return -ENODEV;
        }
 
+       /**
+        * 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);
+       }
+
        down_write(&kni_list_lock);
        list_add(&kni->list, &kni_list_head);
        up_write(&kni_list_lock);
@@ -388,20 +492,12 @@ kni_ioctl_release(unsigned int ioctl_num, unsigned long ioctl_param)
                if (strncmp(dev->name, dev_info.name, RTE_KNI_NAMESIZE) != 0)
                        continue;
 
-               switch (dev->device_id) {
-               #define RTE_PCI_DEV_ID_DECL_IGB(vend, dev) case (dev):
-               #include <rte_pci_dev_ids.h>
-                       igb_kni_remove(dev->pci_dev);
-                       break;
-               #define RTE_PCI_DEV_ID_DECL_IXGBE(vend, dev) case (dev):
-               #include <rte_pci_dev_ids.h>
-                       ixgbe_kni_remove(dev->pci_dev);
-                       break;
-               default:
-                       break;
+               if (multiple_kthread_on && dev->pthread != NULL) {
+                       kthread_stop(dev->pthread);
+                       dev->pthread = NULL;
                }
-               unregister_netdev(dev->net_dev);
-               free_netdev(dev->net_dev);
+
+               kni_dev_remove(dev);
                list_del(&dev->list);
                ret = 0;
                break;
@@ -466,3 +562,11 @@ MODULE_PARM_DESC(lo_mode,
 "\n"
 );
 
+module_param(kthread_mode, charp, S_IRUGO);
+MODULE_PARM_DESC(kthread_mode,
+"Kernel thread mode (default=single):\n"
+"    single    Single kernel thread mode enabled.\n"
+"    multiple  Multiple kernel thread mode enabled.\n"
+"\n"
+);
+

diff --git a/lib/librte_kni/rte_kni.c b/lib/librte_kni/rte_kni.c
index 8e8741f..684af18 100644 (file)
--- a/lib/librte_kni/rte_kni.c
+++ b/lib/librte_kni/rte_kni.c
@@ -179,6 +179,8 @@ rte_kni_alloc(struct rte_mempool *pktmbuf_pool,
        dev_info.function = conf->addr.function;
        dev_info.vendor_id = conf->id.vendor_id;
        dev_info.device_id = conf->id.device_id;
+       dev_info.core_id = conf->core_id;
+       dev_info.force_bind = conf->force_bind;
        dev_info.group_id = conf->group_id;
        dev_info.mbuf_size = conf->mbuf_size;
 

diff --git a/lib/librte_kni/rte_kni.h b/lib/librte_kni/rte_kni.h
index 8be6281..694a899 100644 (file)
--- a/lib/librte_kni/rte_kni.h
+++ b/lib/librte_kni/rte_kni.h
@@ -80,10 +80,13 @@ struct rte_kni_conf {
         * memzone name.
         */
        char name[RTE_KNI_NAMESIZE];
+       uint32_t core_id;   /* Core ID to bind kernel thread on */
        uint16_t group_id;  /* Group ID */
        unsigned mbuf_size; /* mbuf size */
        struct rte_pci_addr addr;
        struct rte_pci_id id;
+
+       uint8_t force_bind : 1; /* Flag to bind kernel thread */
 };
 
 /**