Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Koichiro Den <den@valinux.co.jp>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
authored by
Koichiro Den
and committed by
Jon Mason
8c1f92ca
6a4b5058
+35
-89
+35
-89
drivers/ntb/ntb_transport.c
+35
-89
drivers/ntb/ntb_transport.c
···
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#include <linux/module.h>
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#include <linux/pci.h>
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#include <linux/slab.h>
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#include <linux/seq_file.h>
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#include <linux/types.h>
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#include <linux/uaccess.h>
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#include <linux/mutex.h>
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}
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EXPORT_SYMBOL_GPL(ntb_transport_unregister_client);
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static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count,
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loff_t *offp)
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static int ntb_qp_debugfs_stats_show(struct seq_file *s, void *v)
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{
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struct ntb_transport_qp *qp;
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char *buf;
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ssize_t ret, out_offset, out_count;
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qp = filp->private_data;
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struct ntb_transport_qp *qp = s->private;
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if (!qp || !qp->link_is_up)
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return 0;
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out_count = 1000;
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seq_puts(s, "\nNTB QP stats:\n\n");
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buf = kmalloc(out_count, GFP_KERNEL);
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if (!buf)
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return -ENOMEM;
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seq_printf(s, "rx_bytes - \t%llu\n", qp->rx_bytes);
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seq_printf(s, "rx_pkts - \t%llu\n", qp->rx_pkts);
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seq_printf(s, "rx_memcpy - \t%llu\n", qp->rx_memcpy);
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seq_printf(s, "rx_async - \t%llu\n", qp->rx_async);
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seq_printf(s, "rx_ring_empty - %llu\n", qp->rx_ring_empty);
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seq_printf(s, "rx_err_no_buf - %llu\n", qp->rx_err_no_buf);
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seq_printf(s, "rx_err_oflow - \t%llu\n", qp->rx_err_oflow);
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seq_printf(s, "rx_err_ver - \t%llu\n", qp->rx_err_ver);
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seq_printf(s, "rx_buff - \t0x%p\n", qp->rx_buff);
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seq_printf(s, "rx_index - \t%u\n", qp->rx_index);
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seq_printf(s, "rx_max_entry - \t%u\n", qp->rx_max_entry);
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seq_printf(s, "rx_alloc_entry - \t%u\n\n", qp->rx_alloc_entry);
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out_offset = 0;
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"\nNTB QP stats:\n\n");
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"rx_bytes - \t%llu\n", qp->rx_bytes);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"rx_pkts - \t%llu\n", qp->rx_pkts);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"rx_memcpy - \t%llu\n", qp->rx_memcpy);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"rx_async - \t%llu\n", qp->rx_async);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"rx_ring_empty - %llu\n", qp->rx_ring_empty);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"rx_err_no_buf - %llu\n", qp->rx_err_no_buf);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"rx_err_oflow - \t%llu\n", qp->rx_err_oflow);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"rx_err_ver - \t%llu\n", qp->rx_err_ver);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"rx_buff - \t0x%p\n", qp->rx_buff);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"rx_index - \t%u\n", qp->rx_index);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"rx_max_entry - \t%u\n", qp->rx_max_entry);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"rx_alloc_entry - \t%u\n\n", qp->rx_alloc_entry);
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seq_printf(s, "tx_bytes - \t%llu\n", qp->tx_bytes);
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seq_printf(s, "tx_pkts - \t%llu\n", qp->tx_pkts);
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seq_printf(s, "tx_memcpy - \t%llu\n", qp->tx_memcpy);
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seq_printf(s, "tx_async - \t%llu\n", qp->tx_async);
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seq_printf(s, "tx_ring_full - \t%llu\n", qp->tx_ring_full);
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seq_printf(s, "tx_err_no_buf - %llu\n", qp->tx_err_no_buf);
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seq_printf(s, "tx_mw - \t0x%p\n", qp->tx_mw);
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seq_printf(s, "tx_index (H) - \t%u\n", qp->tx_index);
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seq_printf(s, "RRI (T) - \t%u\n", qp->remote_rx_info->entry);
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seq_printf(s, "tx_max_entry - \t%u\n", qp->tx_max_entry);
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seq_printf(s, "free tx - \t%u\n", ntb_transport_tx_free_entry(qp));
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seq_putc(s, '\n');
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"tx_bytes - \t%llu\n", qp->tx_bytes);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"tx_pkts - \t%llu\n", qp->tx_pkts);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"tx_memcpy - \t%llu\n", qp->tx_memcpy);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"tx_async - \t%llu\n", qp->tx_async);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"tx_ring_full - \t%llu\n", qp->tx_ring_full);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"tx_err_no_buf - %llu\n", qp->tx_err_no_buf);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"tx_mw - \t0x%p\n", qp->tx_mw);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"tx_index (H) - \t%u\n", qp->tx_index);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"RRI (T) - \t%u\n",
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qp->remote_rx_info->entry);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"tx_max_entry - \t%u\n", qp->tx_max_entry);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"free tx - \t%u\n",
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ntb_transport_tx_free_entry(qp));
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seq_printf(s, "Using TX DMA - \t%s\n", qp->tx_dma_chan ? "Yes" : "No");
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seq_printf(s, "Using RX DMA - \t%s\n", qp->rx_dma_chan ? "Yes" : "No");
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seq_printf(s, "QP Link - \t%s\n", qp->link_is_up ? "Up" : "Down");
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seq_putc(s, '\n');
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"\n");
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"Using TX DMA - \t%s\n",
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qp->tx_dma_chan ? "Yes" : "No");
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"Using RX DMA - \t%s\n",
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qp->rx_dma_chan ? "Yes" : "No");
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"QP Link - \t%s\n",
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qp->link_is_up ? "Up" : "Down");
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"\n");
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if (out_offset > out_count)
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out_offset = out_count;
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ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
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kfree(buf);
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return ret;
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return 0;
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}
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static const struct file_operations ntb_qp_debugfs_stats = {
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.owner = THIS_MODULE,
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.open = simple_open,
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.read = debugfs_read,
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};
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DEFINE_SHOW_ATTRIBUTE(ntb_qp_debugfs_stats);
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static void ntb_list_add(spinlock_t *lock, struct list_head *entry,
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struct list_head *list)
···
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qp->debugfs_stats = debugfs_create_file("stats", S_IRUSR,
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qp->debugfs_dir, qp,
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&ntb_qp_debugfs_stats);
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&ntb_qp_debugfs_stats_fops);
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} else {
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qp->debugfs_dir = NULL;
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qp->debugfs_stats = NULL;