From e4cf3aa8f9cd6ee4d583b5d445b5c152acefcde4 Mon Sep 17 00:00:00 2001 From: David Engraf Date: Thu, 20 Mar 2008 10:01:34 +0100 Subject: [PATCH] USB: increase cdc-acm write throughput the following patch uses 16 write urbs and a writsize of wMaxPacketSize * 20. With this patch I get the maximum througput from my linux system with 20MB/sec read and 15 MB/sec write (full speed 1 MB/sec both) I also deleted the flag URB_NO_FSBR for the writeurbs, because this makes my full speed devices significant slower. Signed-off-by: David Engraf Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/cdc-acm.c | 81 +++++++++++++++++++------------------ drivers/usb/class/cdc-acm.h | 7 ++-- 2 files changed, 45 insertions(+), 43 deletions(-) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 1ded83b66a..d9b4081139 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -31,6 +31,7 @@ * v0.23 - use softirq for rx processing, as needed by tty layer * v0.24 - change probe method to evaluate CDC union descriptor * v0.25 - downstream tasks paralelized to maximize throughput + * v0.26 - multiple write urbs, writesize increased */ /* @@ -72,7 +73,7 @@ /* * Version Information */ -#define DRIVER_VERSION "v0.25" +#define DRIVER_VERSION "v0.26" #define DRIVER_AUTHOR "Armin Fuerst, Pavel Machek, Johannes Erdfelt, Vojtech Pavlik, David Kubicek" #define DRIVER_DESC "USB Abstract Control Model driver for USB modems and ISDN adapters" @@ -118,7 +119,7 @@ static int acm_wb_alloc(struct acm *acm) int i, wbn; struct acm_wb *wb; - wbn = acm->write_current; + wbn = 0; i = 0; for (;;) { wb = &acm->wb[wbn]; @@ -132,11 +133,6 @@ static int acm_wb_alloc(struct acm *acm) } } -static void acm_wb_free(struct acm *acm, int wbn) -{ - acm->wb[wbn].use = 0; -} - static int acm_wb_is_avail(struct acm *acm) { int i, n; @@ -156,26 +152,22 @@ static inline int acm_wb_is_used(struct acm *acm, int wbn) /* * Finish write. */ -static void acm_write_done(struct acm *acm) +static void acm_write_done(struct acm *acm, struct acm_wb *wb) { unsigned long flags; - int wbn; spin_lock_irqsave(&acm->write_lock, flags); acm->write_ready = 1; - wbn = acm->write_current; - acm_wb_free(acm, wbn); - acm->write_current = (wbn + 1) % ACM_NW; + wb->use = 0; spin_unlock_irqrestore(&acm->write_lock, flags); } /* * Poke write. */ -static int acm_write_start(struct acm *acm) +static int acm_write_start(struct acm *acm, int wbn) { unsigned long flags; - int wbn; struct acm_wb *wb; int rc; @@ -190,24 +182,24 @@ static int acm_write_start(struct acm *acm) return 0; /* A white lie */ } - wbn = acm->write_current; if (!acm_wb_is_used(acm, wbn)) { spin_unlock_irqrestore(&acm->write_lock, flags); return 0; } wb = &acm->wb[wbn]; - acm->write_ready = 0; + if(acm_wb_is_avail(acm) <= 1) + acm->write_ready = 0; spin_unlock_irqrestore(&acm->write_lock, flags); - acm->writeurb->transfer_buffer = wb->buf; - acm->writeurb->transfer_dma = wb->dmah; - acm->writeurb->transfer_buffer_length = wb->len; - acm->writeurb->dev = acm->dev; + wb->urb->transfer_buffer = wb->buf; + wb->urb->transfer_dma = wb->dmah; + wb->urb->transfer_buffer_length = wb->len; + wb->urb->dev = acm->dev; - if ((rc = usb_submit_urb(acm->writeurb, GFP_ATOMIC)) < 0) { + if ((rc = usb_submit_urb(wb->urb, GFP_ATOMIC)) < 0) { dbg("usb_submit_urb(write bulk) failed: %d", rc); - acm_write_done(acm); + acm_write_done(acm, wb); } return rc; } @@ -450,12 +442,13 @@ urbs: /* data interface wrote those outgoing bytes */ static void acm_write_bulk(struct urb *urb) { - struct acm *acm = (struct acm *)urb->context; + struct acm *acm; + struct acm_wb *wb = (struct acm_wb *)urb->context; dbg("Entering acm_write_bulk with status %d", urb->status); - acm_write_done(acm); - acm_write_start(acm); + acm = wb->instance; + acm_write_done(acm, wb); if (ACM_READY(acm)) schedule_work(&acm->work); } @@ -557,7 +550,8 @@ static void acm_tty_unregister(struct acm *acm) usb_put_intf(acm->control); acm_table[acm->minor] = NULL; usb_free_urb(acm->ctrlurb); - usb_free_urb(acm->writeurb); + for (i = 0; i < ACM_NW; i++) + usb_free_urb(acm->wb[i].urb); for (i = 0; i < nr; i++) usb_free_urb(acm->ru[i].urb); kfree(acm->country_codes); @@ -578,7 +572,8 @@ static void acm_tty_close(struct tty_struct *tty, struct file *filp) if (acm->dev) { acm_set_control(acm, acm->ctrlout = 0); usb_kill_urb(acm->ctrlurb); - usb_kill_urb(acm->writeurb); + for (i = 0; i < ACM_NW; i++) + usb_kill_urb(acm->wb[i].urb); for (i = 0; i < nr; i++) usb_kill_urb(acm->ru[i].urb); usb_autopm_put_interface(acm->control); @@ -606,7 +601,6 @@ static int acm_tty_write(struct tty_struct *tty, const unsigned char *buf, int c spin_lock_irqsave(&acm->write_lock, flags); if ((wbn = acm_wb_alloc(acm)) < 0) { spin_unlock_irqrestore(&acm->write_lock, flags); - acm_write_start(acm); return 0; } wb = &acm->wb[wbn]; @@ -617,7 +611,7 @@ static int acm_tty_write(struct tty_struct *tty, const unsigned char *buf, int c wb->len = count; spin_unlock_irqrestore(&acm->write_lock, flags); - if ((stat = acm_write_start(acm)) < 0) + if ((stat = acm_write_start(acm, wbn)) < 0) return stat; return count; } @@ -977,7 +971,7 @@ skip_normal_probe: ctrlsize = le16_to_cpu(epctrl->wMaxPacketSize); readsize = le16_to_cpu(epread->wMaxPacketSize)* ( quirks == SINGLE_RX_URB ? 1 : 2); - acm->writesize = le16_to_cpu(epwrite->wMaxPacketSize); + acm->writesize = le16_to_cpu(epwrite->wMaxPacketSize) * 20; acm->control = control_interface; acm->data = data_interface; acm->minor = minor; @@ -1032,10 +1026,19 @@ skip_normal_probe: goto alloc_fail7; } } - acm->writeurb = usb_alloc_urb(0, GFP_KERNEL); - if (!acm->writeurb) { - dev_dbg(&intf->dev, "out of memory (writeurb kmalloc)\n"); - goto alloc_fail7; + for(i = 0; i < ACM_NW; i++) + { + struct acm_wb *snd = &(acm->wb[i]); + + if (!(snd->urb = usb_alloc_urb(0, GFP_KERNEL))) { + dev_dbg(&intf->dev, "out of memory (write urbs usb_alloc_urb)"); + goto alloc_fail7; + } + + usb_fill_bulk_urb(snd->urb, usb_dev, usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress), + NULL, acm->writesize, acm_write_bulk, snd); + snd->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; + snd->instance = acm; } usb_set_intfdata (intf, acm); @@ -1071,10 +1074,6 @@ skip_countries: acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; acm->ctrlurb->transfer_dma = acm->ctrl_dma; - usb_fill_bulk_urb(acm->writeurb, usb_dev, usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress), - NULL, acm->writesize, acm_write_bulk, acm); - acm->writeurb->transfer_flags |= URB_NO_FSBR | URB_NO_TRANSFER_DMA_MAP; - dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor); acm_set_control(acm, acm->ctrlout); @@ -1092,7 +1091,8 @@ skip_countries: return 0; alloc_fail8: - usb_free_urb(acm->writeurb); + for (i = 0; i < ACM_NW; i++) + usb_free_urb(acm->wb[i].urb); alloc_fail7: for (i = 0; i < num_rx_buf; i++) usb_buffer_free(usb_dev, acm->readsize, acm->rb[i].base, acm->rb[i].dma); @@ -1116,7 +1116,8 @@ static void stop_data_traffic(struct acm *acm) tasklet_disable(&acm->urb_task); usb_kill_urb(acm->ctrlurb); - usb_kill_urb(acm->writeurb); + for(i = 0; i < ACM_NW; i++) + usb_kill_urb(acm->wb[i].urb); for (i = 0; i < acm->rx_buflimit; i++) usb_kill_urb(acm->ru[i].urb); diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h index 8df6a57dcf..046e064b03 100644 --- a/drivers/usb/class/cdc-acm.h +++ b/drivers/usb/class/cdc-acm.h @@ -59,7 +59,7 @@ * when processing onlcr, so we only need 2 buffers. These values must be * powers of 2. */ -#define ACM_NW 2 +#define ACM_NW 16 #define ACM_NR 16 struct acm_wb { @@ -67,6 +67,8 @@ struct acm_wb { dma_addr_t dmah; int len; int use; + struct urb *urb; + struct acm *instance; }; struct acm_rb { @@ -88,7 +90,7 @@ struct acm { struct usb_interface *control; /* control interface */ struct usb_interface *data; /* data interface */ struct tty_struct *tty; /* the corresponding tty */ - struct urb *ctrlurb, *writeurb; /* urbs */ + struct urb *ctrlurb; /* urbs */ u8 *ctrl_buffer; /* buffers of urbs */ dma_addr_t ctrl_dma; /* dma handles of buffers */ u8 *country_codes; /* country codes from device */ @@ -103,7 +105,6 @@ struct acm { struct list_head spare_read_urbs; struct list_head spare_read_bufs; struct list_head filled_read_bufs; - int write_current; /* current write buffer */ int write_used; /* number of non-empty write buffers */ int write_ready; /* write urb is not running */ spinlock_t write_lock; -- 2.39.5