bonding: add the debugfs interface to see RLB hash table

This patch provices the debugfs interface to see RLB hash table
like the following:

# cat /sys/kernel/debug/bonding/bond0/rlb_hash_table
SourceIP        DestinationIP   Destination MAC   DEV
10.124.196.205  10.124.196.205  ff:ff:ff:ff:ff:ff eth4
10.124.196.205  10.124.196.81   00:19:99:XX:XX:XX eth3
10.124.196.205  10.124.196.1    00:21:d8:XX:XX:XX eth0

This is helpful to check if the receive load balancing works as expected.

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 50 insertions, 0 deletions

diff --git a/drivers/net/bonding/bond_debugfs.c b/drivers/net/bonding/bond_debugfs.c
index ae1eb2fc3a4..3680aa251de 100644
--- a/drivers/net/bonding/bond_debugfs.c
+++ b/drivers/net/bonding/bond_debugfs.c
@@ -4,6 +4,7 @@
 #include <linux/netdevice.h>
 
 #include "bonding.h"
+#include "bond_alb.h"
 
 #ifdef CONFIG_DEBUG_FS
 
@@ -12,6 +13,52 @@
 
 static struct dentry *bonding_debug_root;
 
+/*
+ *  Show RLB hash table
+ */
+static int bond_debug_rlb_hash_show(struct seq_file *m, void *v)
+{
+        struct bonding *bond = m->private;
+        struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+        struct rlb_client_info *client_info;
+        u32 hash_index;
+
+        if (bond->params.mode != BOND_MODE_ALB)
+                return 0;
+
+        seq_printf(m, "SourceIP        DestinationIP   "
+                        "Destination MAC   DEV\n");
+
+        spin_lock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
+
+        hash_index = bond_info->rx_hashtbl_head;
+        for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
+                client_info = &(bond_info->rx_hashtbl[hash_index]);
+                seq_printf(m, "%-15pI4 %-15pI4 %-17pM %s\n",
+                        &client_info->ip_src,
+                        &client_info->ip_dst,
+                        &client_info->mac_dst,
+                        client_info->slave->dev->name);
+        }
+
+        spin_unlock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
+
+        return 0;
+}
+
+static int bond_debug_rlb_hash_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, bond_debug_rlb_hash_show, inode->i_private);
+}
+
+static const struct file_operations bond_debug_rlb_hash_fops = {
+        .owner          = THIS_MODULE,
+        .open           = bond_debug_rlb_hash_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+};
+
 void bond_debug_register(struct bonding *bond)
 {
         if (!bonding_debug_root)
@@ -25,6 +72,9 @@ void bond_debug_register(struct bonding *bond)
                         bond->dev->name);
                 return;
         }
+
+        debugfs_create_file("rlb_hash_table", 0400, bond->debug_dir,
+                                bond, &bond_debug_rlb_hash_fops);
 }
 
 void bond_debug_unregister(struct bonding *bond)