| Message ID | 1592310884-4307-2-git-send-email-macpaul.lin@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] usb: gadget: introduce flag for large request | expand |
Hi, Macpaul Lin <macpaul.lin@mediatek.com> writes: > If the hardware (like DMA engine) could support large usb request exceeds > maximum packet size, use larger buffer when performing Rx/Tx could reduce > request numbers and improve performance. > > Signed-off-by: Macpaul Lin <macpaul.lin@mediatek.com> > --- > drivers/usb/gadget/function/u_serial.c | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c > index 3cfc6e2..cdcc070 100644 > --- a/drivers/usb/gadget/function/u_serial.c > +++ b/drivers/usb/gadget/function/u_serial.c > @@ -80,6 +80,8 @@ > #define QUEUE_SIZE 16 > #define WRITE_BUF_SIZE 8192 /* TX only */ > #define GS_CONSOLE_BUF_SIZE 8192 > +/* for hardware can do more than max packet */ > +#define REQ_BUF_SIZE 4096 > > /* console info */ > struct gs_console { > @@ -247,7 +249,8 @@ static int gs_start_tx(struct gs_port *port) > break; > > req = list_entry(pool->next, struct usb_request, list); > - len = gs_send_packet(port, req->buf, in->maxpacket); > + len = gs_send_packet(port, req->buf, in->can_exceed_maxp ? > + REQ_BUF_SIZE : in->maxpacket); just do this unconditionally. > if (len == 0) { > wake_up_interruptible(&port->drain_wait); > break; > @@ -514,7 +517,9 @@ static int gs_alloc_requests(struct usb_ep *ep, struct list_head *head, > * be as speedy as we might otherwise be. > */ > for (i = 0; i < n; i++) { > - req = gs_alloc_req(ep, ep->maxpacket, GFP_ATOMIC); > + req = gs_alloc_req(ep, ep->can_exceed_maxp ? > + REQ_BUF_SIZE : ep->maxpacket, > + GFP_ATOMIC); allocating 4kiB in atomic isn't very good. A better idea would be to preallocate a list of requests and recycle them, rather than allocating every time you need to do a transfer
diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c index 3cfc6e2..cdcc070 100644 --- a/drivers/usb/gadget/function/u_serial.c +++ b/drivers/usb/gadget/function/u_serial.c @@ -80,6 +80,8 @@ #define QUEUE_SIZE 16 #define WRITE_BUF_SIZE 8192 /* TX only */ #define GS_CONSOLE_BUF_SIZE 8192 +/* for hardware can do more than max packet */ +#define REQ_BUF_SIZE 4096 /* console info */ struct gs_console { @@ -247,7 +249,8 @@ static int gs_start_tx(struct gs_port *port) break; req = list_entry(pool->next, struct usb_request, list); - len = gs_send_packet(port, req->buf, in->maxpacket); + len = gs_send_packet(port, req->buf, in->can_exceed_maxp ? + REQ_BUF_SIZE : in->maxpacket); if (len == 0) { wake_up_interruptible(&port->drain_wait); break; @@ -514,7 +517,9 @@ static int gs_alloc_requests(struct usb_ep *ep, struct list_head *head, * be as speedy as we might otherwise be. */ for (i = 0; i < n; i++) { - req = gs_alloc_req(ep, ep->maxpacket, GFP_ATOMIC); + req = gs_alloc_req(ep, ep->can_exceed_maxp ? + REQ_BUF_SIZE : ep->maxpacket, + GFP_ATOMIC); if (!req) return list_empty(head) ? -ENOMEM : 0; req->complete = fn;
If the hardware (like DMA engine) could support large usb request exceeds maximum packet size, use larger buffer when performing Rx/Tx could reduce request numbers and improve performance. Signed-off-by: Macpaul Lin <macpaul.lin@mediatek.com> --- drivers/usb/gadget/function/u_serial.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)