cxgb4: Add debugfs facility to inject FL starvation

[linux-2.6-microblaze.git] / drivers / net / ethernet / chelsio / cxgb4 / cxgb4_debugfs.c

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
index 371f75e..3fa3632 100644 (file)
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
@@ -1959,6 +1959,61 @@ static void add_debugfs_mem(struct adapter *adap, const char *name,
                                 size_mb << 20);
 }
 
+static int blocked_fl_open(struct inode *inode, struct file *file)
+{
+       file->private_data = inode->i_private;
+       return 0;
+}
+
+static ssize_t blocked_fl_read(struct file *filp, char __user *ubuf,
+                              size_t count, loff_t *ppos)
+{
+       int len;
+       const struct adapter *adap = filp->private_data;
+       char *buf;
+       ssize_t size = (adap->sge.egr_sz + 3) / 4 +
+                       adap->sge.egr_sz / 32 + 2; /* includes ,/\n/\0 */
+
+       buf = kzalloc(size, GFP_KERNEL);
+       if (!buf)
+               return -ENOMEM;
+
+       len = snprintf(buf, size - 1, "%*pb\n",
+                      adap->sge.egr_sz, adap->sge.blocked_fl);
+       len += sprintf(buf + len, "\n");
+       size = simple_read_from_buffer(ubuf, count, ppos, buf, len);
+       t4_free_mem(buf);
+       return size;
+}
+
+static ssize_t blocked_fl_write(struct file *filp, const char __user *ubuf,
+                               size_t count, loff_t *ppos)
+{
+       int err;
+       unsigned long *t;
+       struct adapter *adap = filp->private_data;
+
+       t = kcalloc(BITS_TO_LONGS(adap->sge.egr_sz), sizeof(long), GFP_KERNEL);
+       if (!t)
+               return -ENOMEM;
+
+       err = bitmap_parse_user(ubuf, count, t, adap->sge.egr_sz);
+       if (err)
+               return err;
+
+       bitmap_copy(adap->sge.blocked_fl, t, adap->sge.egr_sz);
+       t4_free_mem(t);
+       return count;
+}
+
+static const struct file_operations blocked_fl_fops = {
+       .owner   = THIS_MODULE,
+       .open    = blocked_fl_open,
+       .read    = blocked_fl_read,
+       .write   = blocked_fl_write,
+       .llseek  = generic_file_llseek,
+};
+
 /* Add an array of Debug FS files.
  */
 void add_debugfs_files(struct adapter *adap,
@@ -2022,6 +2077,7 @@ int t4_setup_debugfs(struct adapter *adap)
 #if IS_ENABLED(CONFIG_IPV6)
                { "clip_tbl", &clip_tbl_debugfs_fops, S_IRUSR, 0 },
 #endif
+               { "blocked_fl", &blocked_fl_fops, S_IRUSR | S_IWUSR, 0 },
        };
 
        /* Debug FS nodes common to all T5 and later adapters.