channel_rb_show.patch

channel_rb_show.patch

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 64713ff..e51b080 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -476,6 +476,68 @@ static ssize_t channel_vp_mapping_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(channel_vp_mapping);
 
+static ssize_t channel_rb_show(struct device *dev,
+				       struct device_attribute *dev_attr,
+				       char *buf)
+{
+	struct hv_device *hv_dev = device_to_hv_device(dev);
+	struct vmbus_channel *channel = hv_dev->channel, *cur_sc;
+	unsigned long flags;
+	int buf_size = PAGE_SIZE, n_written, tot_written;
+	struct list_head *cur;
+
+	struct hv_ring_buffer_debug_info inbound;
+	struct hv_ring_buffer_debug_info outbound;
+	int nr = 0;
+
+	if (!channel)
+		return -ENODEV;
+
+	hv_ringbuffer_get_debuginfo(&channel->inbound, &inbound);
+	hv_ringbuffer_get_debuginfo(&channel->outbound, &outbound);
+
+	tot_written = snprintf(buf, buf_size,
+"channel #[%d:%d]: in_intr_mask=%u, in_pending_send_sz=%u, in_read_bytes_avail=%u, in_write_bytes_avail=%u, in_read_index=%u, in_write_index=%u;out_intr_mask=%u, out_pending_send_sz=%u, out_read_bytes_avail=%u, out_write_bytes_avail=%u, out_read_index=%u, out_write_index=%u\n",
+	nr, channel->offermsg.child_relid, inbound.current_interrupt_mask,
+	channel->inbound.ring_buffer->pending_send_sz,
+	inbound.bytes_avail_toread, inbound.bytes_avail_towrite,
+	inbound.current_read_index, inbound.current_write_index,
+	outbound.current_interrupt_mask,
+	channel->outbound.ring_buffer->pending_send_sz,
+	outbound.bytes_avail_toread, outbound.bytes_avail_towrite,
+	outbound.current_read_index, outbound.current_write_index);
+
+	spin_lock_irqsave(&channel->lock, flags);
+
+	list_for_each(cur, &channel->sc_list) {
+		if (tot_written >= buf_size - 1)
+			break;
+
+		cur_sc = list_entry(cur, struct vmbus_channel, sc_list);
+		hv_ringbuffer_get_debuginfo(&cur_sc->inbound, &inbound);
+		hv_ringbuffer_get_debuginfo(&cur_sc->outbound, &outbound);
+
+		++nr;
+		n_written = scnprintf(buf + tot_written,
+				     buf_size - tot_written,
+"channel #[%d:%d]: in_intr_mask=%u, in_pending_send_sz=%u, in_read_bytes_avail=%u, in_write_bytes_avail=%u, in_read_index=%u, in_write_index=%u;out_intr_mask=%u, out_pending_send_sz=%u, out_read_bytes_avail=%u, out_write_bytes_avail=%u, out_read_index=%u, out_write_index=%u\n",
+		nr, cur_sc->offermsg.child_relid, inbound.current_interrupt_mask,
+		cur_sc->inbound.ring_buffer->pending_send_sz,
+		inbound.bytes_avail_toread, inbound.bytes_avail_towrite,
+		inbound.current_read_index, inbound.current_write_index,
+		outbound.current_interrupt_mask,
+		cur_sc->outbound.ring_buffer->pending_send_sz,
+		outbound.bytes_avail_toread, outbound.bytes_avail_towrite,
+		outbound.current_read_index, outbound.current_write_index);
+		tot_written += n_written;
+	}
+
+	spin_unlock_irqrestore(&channel->lock, flags);
+
+	return tot_written;
+}
+static DEVICE_ATTR_RO(channel_rb);
+
 static ssize_t vendor_show(struct device *dev,
 			   struct device_attribute *dev_attr,
 			   char *buf)
@@ -519,6 +581,7 @@ static struct attribute *vmbus_attrs[] = {
 	&dev_attr_in_read_bytes_avail.attr,
 	&dev_attr_in_write_bytes_avail.attr,
 	&dev_attr_channel_vp_mapping.attr,
+	&dev_attr_channel_rb.attr,
 	&dev_attr_vendor.attr,
 	&dev_attr_device.attr,
 	NULL,