From d83b405383c965498923f3561c3321e2b5df5727 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Sun, 6 Nov 2011 19:06:37 +0100 Subject: [PATCH] USB: serial: add support for multiple read urbs Add support for multiple read urbs to generic read implementation. Use a static array of two read urbs for now which is enough to get a 50% throughput increase in one test setup. Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/generic.c | 83 ++++++++++++++++++++++++--------- drivers/usb/serial/usb-serial.c | 50 ++++++++++++-------- include/linux/usb/serial.h | 9 +++- 3 files changed, 101 insertions(+), 41 deletions(-) diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c index e4db5ad2bc55..f7403576f99f 100644 --- a/drivers/usb/serial/generic.c +++ b/drivers/usb/serial/generic.c @@ -1,7 +1,7 @@ /* * USB Serial Converter Generic functions * - * Copyright (C) 2010 Johan Hovold (jhovold@gmail.com) + * Copyright (C) 2010 - 2011 Johan Hovold (jhovold@gmail.com) * Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com) * * This program is free software; you can redistribute it and/or @@ -132,7 +132,7 @@ int usb_serial_generic_open(struct tty_struct *tty, struct usb_serial_port *port /* if we have a bulk endpoint, start reading from it */ if (port->bulk_in_size) - result = usb_serial_generic_submit_read_urb(port, GFP_KERNEL); + result = usb_serial_generic_submit_read_urbs(port, GFP_KERNEL); return result; } @@ -157,8 +157,10 @@ static void generic_cleanup(struct usb_serial_port *port) kfifo_reset_out(&port->write_fifo); spin_unlock_irqrestore(&port->lock, flags); } - if (port->bulk_in_size) - usb_kill_urb(port->read_urb); + if (port->bulk_in_size) { + for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) + usb_kill_urb(port->read_urbs[i]); + } } } @@ -308,19 +310,52 @@ int usb_serial_generic_chars_in_buffer(struct tty_struct *tty) return chars; } -int usb_serial_generic_submit_read_urb(struct usb_serial_port *port, +static int usb_serial_generic_submit_read_urb(struct usb_serial_port *port, + int index, gfp_t mem_flags) +{ + int res; + + if (!test_and_clear_bit(index, &port->read_urbs_free)) + return 0; + + dbg("%s - port %d, urb %d\n", __func__, port->number, index); + + res = usb_submit_urb(port->read_urbs[index], mem_flags); + if (res) { + if (res != -EPERM) { + dev_err(&port->dev, + "%s - usb_submit_urb failed: %d\n", + __func__, res); + } + set_bit(index, &port->read_urbs_free); + return res; + } + + return 0; +} + +int usb_serial_generic_submit_read_urbs(struct usb_serial_port *port, gfp_t mem_flags) { - int result; + int res; + int i; - result = usb_submit_urb(port->read_urb, mem_flags); - if (result && result != -EPERM) { - dev_err(&port->dev, "%s - error submitting urb: %d\n", - __func__, result); + dbg("%s - port %d", __func__, port->number); + + for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) { + res = usb_serial_generic_submit_read_urb(port, i, mem_flags); + if (res) + goto err; } - return result; + + return 0; +err: + for (; i >= 0; --i) + usb_kill_urb(port->read_urbs[i]); + + return res; } -EXPORT_SYMBOL_GPL(usb_serial_generic_submit_read_urb); +EXPORT_SYMBOL_GPL(usb_serial_generic_submit_read_urbs); void usb_serial_generic_process_read_urb(struct urb *urb) { @@ -356,14 +391,19 @@ void usb_serial_generic_read_bulk_callback(struct urb *urb) { struct usb_serial_port *port = urb->context; unsigned char *data = urb->transfer_buffer; - int status = urb->status; unsigned long flags; + int i; - dbg("%s - port %d", __func__, port->number); + for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) { + if (urb == port->read_urbs[i]) + break; + } + set_bit(i, &port->read_urbs_free); - if (unlikely(status != 0)) { - dbg("%s - nonzero read bulk status received: %d", - __func__, status); + dbg("%s - port %d, urb %d, len %d\n", __func__, port->number, i, + urb->actual_length); + if (urb->status) { + dbg("%s - non-zero urb status: %d\n", __func__, urb->status); return; } @@ -376,7 +416,7 @@ void usb_serial_generic_read_bulk_callback(struct urb *urb) port->throttled = port->throttle_req; if (!port->throttled) { spin_unlock_irqrestore(&port->lock, flags); - usb_serial_generic_submit_read_urb(port, GFP_ATOMIC); + usb_serial_generic_submit_read_urb(port, i, GFP_ATOMIC); } else spin_unlock_irqrestore(&port->lock, flags); } @@ -443,7 +483,7 @@ void usb_serial_generic_unthrottle(struct tty_struct *tty) spin_unlock_irq(&port->lock); if (was_throttled) - usb_serial_generic_submit_read_urb(port, GFP_KERNEL); + usb_serial_generic_submit_read_urbs(port, GFP_KERNEL); } EXPORT_SYMBOL_GPL(usb_serial_generic_unthrottle); @@ -509,8 +549,9 @@ int usb_serial_generic_resume(struct usb_serial *serial) if (!test_bit(ASYNCB_INITIALIZED, &port->port.flags)) continue; - if (port->read_urb) { - r = usb_submit_urb(port->read_urb, GFP_NOIO); + if (port->bulk_in_size) { + r = usb_serial_generic_submit_read_urbs(port, + GFP_NOIO); if (r < 0) c++; } diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c index bfbe6e5431d3..8d5190f3d8eb 100644 --- a/drivers/usb/serial/usb-serial.c +++ b/drivers/usb/serial/usb-serial.c @@ -562,7 +562,8 @@ static void kill_traffic(struct usb_serial_port *port) { int i; - usb_kill_urb(port->read_urb); + for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) + usb_kill_urb(port->read_urbs[i]); for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) usb_kill_urb(port->write_urbs[i]); /* @@ -594,15 +595,17 @@ static void port_release(struct device *dev) kill_traffic(port); cancel_work_sync(&port->work); - usb_free_urb(port->read_urb); usb_free_urb(port->interrupt_in_urb); usb_free_urb(port->interrupt_out_urb); + for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) { + usb_free_urb(port->read_urbs[i]); + kfree(port->bulk_in_buffers[i]); + } for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) { usb_free_urb(port->write_urbs[i]); kfree(port->bulk_out_buffers[i]); } kfifo_free(&port->write_fifo); - kfree(port->bulk_in_buffer); kfree(port->interrupt_in_buffer); kfree(port->interrupt_out_buffer); kfree(port); @@ -721,6 +724,7 @@ int usb_serial_probe(struct usb_interface *interface, unsigned int minor; int buffer_size; int i; + int j; int num_interrupt_in = 0; int num_interrupt_out = 0; int num_bulk_in = 0; @@ -903,31 +907,39 @@ int usb_serial_probe(struct usb_interface *interface, for (i = 0; i < num_bulk_in; ++i) { endpoint = bulk_in_endpoint[i]; port = serial->port[i]; - port->read_urb = usb_alloc_urb(0, GFP_KERNEL); - if (!port->read_urb) { - dev_err(&interface->dev, "No free urbs available\n"); - goto probe_error; - } buffer_size = max_t(int, serial->type->bulk_in_size, usb_endpoint_maxp(endpoint)); port->bulk_in_size = buffer_size; port->bulk_in_endpointAddress = endpoint->bEndpointAddress; - port->bulk_in_buffer = kmalloc(buffer_size, GFP_KERNEL); - if (!port->bulk_in_buffer) { - dev_err(&interface->dev, + + for (j = 0; j < ARRAY_SIZE(port->read_urbs); ++j) { + set_bit(j, &port->read_urbs_free); + port->read_urbs[j] = usb_alloc_urb(0, GFP_KERNEL); + if (!port->read_urbs[j]) { + dev_err(&interface->dev, + "No free urbs available\n"); + goto probe_error; + } + port->bulk_in_buffers[j] = kmalloc(buffer_size, + GFP_KERNEL); + if (!port->bulk_in_buffers[j]) { + dev_err(&interface->dev, "Couldn't allocate bulk_in_buffer\n"); - goto probe_error; - } - usb_fill_bulk_urb(port->read_urb, dev, - usb_rcvbulkpipe(dev, + goto probe_error; + } + usb_fill_bulk_urb(port->read_urbs[j], dev, + usb_rcvbulkpipe(dev, endpoint->bEndpointAddress), - port->bulk_in_buffer, buffer_size, - serial->type->read_bulk_callback, port); + port->bulk_in_buffers[j], buffer_size, + serial->type->read_bulk_callback, + port); + } + + port->read_urb = port->read_urbs[0]; + port->bulk_in_buffer = port->bulk_in_buffers[0]; } for (i = 0; i < num_bulk_out; ++i) { - int j; - endpoint = bulk_out_endpoint[i]; port = serial->port[i]; if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL)) diff --git a/include/linux/usb/serial.h b/include/linux/usb/serial.h index 8ccd405e9005..4267a9c717ba 100644 --- a/include/linux/usb/serial.h +++ b/include/linux/usb/serial.h @@ -58,6 +58,9 @@ enum port_dev_state { * @read_urb: pointer to the bulk in struct urb for this port. * @bulk_in_endpointAddress: endpoint address for the bulk in pipe for this * port. + * @bulk_in_buffers: pointers to the bulk in buffers for this port + * @read_urbs: pointers to the bulk in urbs for this port + * @read_urbs_free: status bitmap the for bulk in urbs * @bulk_out_buffer: pointer to the bulk out buffer for this port. * @bulk_out_size: the size of the bulk_out_buffer, in bytes. * @write_urb: pointer to the bulk out struct urb for this port. @@ -98,6 +101,10 @@ struct usb_serial_port { struct urb *read_urb; __u8 bulk_in_endpointAddress; + unsigned char *bulk_in_buffers[2]; + struct urb *read_urbs[2]; + unsigned long read_urbs_free; + unsigned char *bulk_out_buffer; int bulk_out_size; struct urb *write_urb; @@ -338,7 +345,7 @@ extern void usb_serial_generic_disconnect(struct usb_serial *serial); extern void usb_serial_generic_release(struct usb_serial *serial); extern int usb_serial_generic_register(int debug); extern void usb_serial_generic_deregister(void); -extern int usb_serial_generic_submit_read_urb(struct usb_serial_port *port, +extern int usb_serial_generic_submit_read_urbs(struct usb_serial_port *port, gfp_t mem_flags); extern void usb_serial_generic_process_read_urb(struct urb *urb); extern int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port, -- 2.39.5