USB3 devices, because they are much newer, have much
less chance of having issues with larger transfers.
We still keep a limit because anything above 2048
sectors really rendered negligible speed
improvements, so we will simply ignore
that. Transferring 1MiB should already give us
pretty good performance.
Signed-off-by: Felipe Balbi <balbi@xxxxxx>
---
drivers/usb/storage/scsiglue.c | 16 +++++++++++-----
drivers/usb/storage/usb.c | 4 ++++
include/linux/usb_usual.h | 2 ++
3 files changed, 17 insertions(+), 5 deletions(-)
diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c
index 00aadf3a3857..bda2b3c9ae42 100644
--- a/drivers/usb/storage/scsiglue.c
+++ b/drivers/usb/storage/scsiglue.c
@@ -115,13 +115,19 @@ static int slave_configure(struct scsi_device *sdev)
{
struct us_data *us = host_to_us(sdev->host);
- /* Many devices have trouble transferring more than 32KB at a time,
- * while others have trouble with more than 64K. At this time we
- * are limiting both to 32K (64 sectores).
- */
- if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
+ if (us->fflags & US_FL_USB3) {
+ /* USB3 devices will be limitted at 2048 sectors. This gives us
+ * close to 25% throughput improvement on some devices.
+ */
+ blk_queue_max_hw_sectors(sdev->request_queue, 2048);
+ } else if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
unsigned int max_sectors = 64;
+ /* Many devices have trouble transferring more than 32KB at a
+ * time, while others have trouble with more than 64K. At this
+ * time we are limiting both to 32K (64 sectores).
+ */
+
if (us->fflags & US_FL_MAX_SECTORS_MIN)
max_sectors = PAGE_CACHE_SIZE >> 9;
if (queue_max_hw_sectors(sdev->request_queue) > max_sectors)
diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c
index 43576ed31ccd..b7735c9850f8 100644
--- a/drivers/usb/storage/usb.c
+++ b/drivers/usb/storage/usb.c
@@ -594,6 +594,10 @@ static int get_device_info(struct us_data *us, const struct usb_device_id *id,
return -ENODEV;
}
+ /* Flag USB3 devices so we can increase max_sectors to 2048 sectors. */
+ if (dev->speed == USB_SPEED_SUPER)
+ us->fflags |= US_FL_USB3;
+
/*
* This flag is only needed when we're in high-speed, so let's
* disable it if we're in full-speed
diff --git a/include/linux/usb_usual.h b/include/linux/usb_usual.h
index 7f5f78bd15ad..b76b0faaedc8 100644
--- a/include/linux/usb_usual.h
+++ b/include/linux/usb_usual.h
@@ -79,6 +79,8 @@
/* Cannot handle MI_REPORT_SUPPORTED_OPERATION_CODES */ \
US_FLAG(MAX_SECTORS_240, 0x08000000) \
/* Sets max_sectors to 240 */ \
+ US_FLAG(USB3, 0x10000000) \
+ /* This is a USB3 Storage Device */ \
#define US_FLAG(name, value) US_FL_##name = value ,
enum { US_DO_ALL_FLAGS };
--
2.6.2
--
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