Commit 8c1f92ca authored by Koichiro Den's avatar Koichiro Den Committed by Jon Mason
Browse files

NTB: ntb_transport: Use seq_file for QP stats debugfs 



The ./qp*/stats debugfs file for each NTB transport QP is currently
implemented with a hand-crafted kmalloc() buffer and a series of
scnprintf() calls. This is a pre-seq_file style pattern and makes future
extensions easy to truncate.

Convert the stats file to use the seq_file helpers via
DEFINE_SHOW_ATTRIBUTE(), which simplifies the code and lets the seq_file
core handle buffering and partial reads.

Reviewed-by: default avatarFrank Li <Frank.Li@nxp.com>
Reviewed-by: default avatarDave Jiang <dave.jiang@intel.com>
Signed-off-by: default avatarKoichiro Den <den@valinux.co.jp>
Signed-off-by: default avatarJon Mason <jdmason@kudzu.us>
parent 6a4b5058

drivers/ntb/ntb_transport.c

+39 −93
Original line number Diff line number Diff line
@@ -58,6 +58,7 @@ 
#include <linux/module.h>

#include <linux/pci.h>

#include <linux/slab.h>

#include <linux/seq_file.h>

#include <linux/types.h>

#include <linux/uaccess.h>

#include <linux/mutex.h>
@@ -482,104 +483,49 @@ void ntb_transport_unregister_client(struct ntb_transport_client *drv) 
}

EXPORT_SYMBOL_GPL(ntb_transport_unregister_client);



static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count,

			    loff_t *offp)

static int ntb_qp_debugfs_stats_show(struct seq_file *s, void *v)

{

	struct ntb_transport_qp *qp;

	char *buf;

	ssize_t ret, out_offset, out_count;



	qp = filp->private_data;

	struct ntb_transport_qp *qp = s->private;



	if (!qp || !qp->link_is_up)

		return 0;



	out_count = 1000;



	buf = kmalloc(out_count, GFP_KERNEL);

	if (!buf)

		return -ENOMEM;

	seq_puts(s, "\nNTB QP stats:\n\n");



	seq_printf(s, "rx_bytes - \t%llu\n", qp->rx_bytes);

	seq_printf(s, "rx_pkts - \t%llu\n", qp->rx_pkts);

	seq_printf(s, "rx_memcpy - \t%llu\n", qp->rx_memcpy);

	seq_printf(s, "rx_async - \t%llu\n", qp->rx_async);

	seq_printf(s, "rx_ring_empty - %llu\n", qp->rx_ring_empty);

	seq_printf(s, "rx_err_no_buf - %llu\n", qp->rx_err_no_buf);

	seq_printf(s, "rx_err_oflow - \t%llu\n", qp->rx_err_oflow);

	seq_printf(s, "rx_err_ver - \t%llu\n", qp->rx_err_ver);

	seq_printf(s, "rx_buff - \t0x%p\n", qp->rx_buff);

	seq_printf(s, "rx_index - \t%u\n", qp->rx_index);

	seq_printf(s, "rx_max_entry - \t%u\n", qp->rx_max_entry);

	seq_printf(s, "rx_alloc_entry - \t%u\n\n", qp->rx_alloc_entry);



	seq_printf(s, "tx_bytes - \t%llu\n", qp->tx_bytes);

	seq_printf(s, "tx_pkts - \t%llu\n", qp->tx_pkts);

	seq_printf(s, "tx_memcpy - \t%llu\n", qp->tx_memcpy);

	seq_printf(s, "tx_async - \t%llu\n", qp->tx_async);

	seq_printf(s, "tx_ring_full - \t%llu\n", qp->tx_ring_full);

	seq_printf(s, "tx_err_no_buf - %llu\n", qp->tx_err_no_buf);

	seq_printf(s, "tx_mw - \t0x%p\n", qp->tx_mw);

	seq_printf(s, "tx_index (H) - \t%u\n", qp->tx_index);

	seq_printf(s, "RRI (T) - \t%u\n", qp->remote_rx_info->entry);

	seq_printf(s, "tx_max_entry - \t%u\n", qp->tx_max_entry);

	seq_printf(s, "free tx - \t%u\n", ntb_transport_tx_free_entry(qp));

	seq_putc(s, '\n');



	seq_printf(s, "Using TX DMA - \t%s\n", qp->tx_dma_chan ? "Yes" : "No");

	seq_printf(s, "Using RX DMA - \t%s\n", qp->rx_dma_chan ? "Yes" : "No");

	seq_printf(s, "QP Link - \t%s\n", qp->link_is_up ? "Up" : "Down");

	seq_putc(s, '\n');



	out_offset = 0;

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "\nNTB QP stats:\n\n");

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "rx_bytes - \t%llu\n", qp->rx_bytes);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "rx_pkts - \t%llu\n", qp->rx_pkts);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "rx_memcpy - \t%llu\n", qp->rx_memcpy);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "rx_async - \t%llu\n", qp->rx_async);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "rx_ring_empty - %llu\n", qp->rx_ring_empty);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "rx_err_no_buf - %llu\n", qp->rx_err_no_buf);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "rx_err_oflow - \t%llu\n", qp->rx_err_oflow);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "rx_err_ver - \t%llu\n", qp->rx_err_ver);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "rx_buff - \t0x%p\n", qp->rx_buff);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "rx_index - \t%u\n", qp->rx_index);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "rx_max_entry - \t%u\n", qp->rx_max_entry);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "rx_alloc_entry - \t%u\n\n", qp->rx_alloc_entry);



	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "tx_bytes - \t%llu\n", qp->tx_bytes);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "tx_pkts - \t%llu\n", qp->tx_pkts);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "tx_memcpy - \t%llu\n", qp->tx_memcpy);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "tx_async - \t%llu\n", qp->tx_async);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "tx_ring_full - \t%llu\n", qp->tx_ring_full);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "tx_err_no_buf - %llu\n", qp->tx_err_no_buf);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "tx_mw - \t0x%p\n", qp->tx_mw);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "tx_index (H) - \t%u\n", qp->tx_index);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "RRI (T) - \t%u\n",

			       qp->remote_rx_info->entry);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "tx_max_entry - \t%u\n", qp->tx_max_entry);

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "free tx - \t%u\n",

			       ntb_transport_tx_free_entry(qp));



	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "\n");

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "Using TX DMA - \t%s\n",

			       qp->tx_dma_chan ? "Yes" : "No");

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "Using RX DMA - \t%s\n",

			       qp->rx_dma_chan ? "Yes" : "No");

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "QP Link - \t%s\n",

			       qp->link_is_up ? "Up" : "Down");

	out_offset += scnprintf(buf + out_offset, out_count - out_offset,

			       "\n");



	if (out_offset > out_count)

		out_offset = out_count;



	ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);

	kfree(buf);

	return ret;

}



static const struct file_operations ntb_qp_debugfs_stats = {

	.owner = THIS_MODULE,

	.open = simple_open,

	.read = debugfs_read,

};

	return 0;

}

DEFINE_SHOW_ATTRIBUTE(ntb_qp_debugfs_stats);



static void ntb_list_add(spinlock_t *lock, struct list_head *entry,

			 struct list_head *list)
@@ -1260,7 +1206,7 @@ static int ntb_transport_init_queue(struct ntb_transport_ctx *nt, 


		qp->debugfs_stats = debugfs_create_file("stats", S_IRUSR,

							qp->debugfs_dir, qp,

							&ntb_qp_debugfs_stats);

							&ntb_qp_debugfs_stats_fops);

	} else {

		qp->debugfs_dir = NULL;

		qp->debugfs_stats = NULL;