Hi Paul, On Tue, Sep 10, 2024 at 3:31 AM Paul Menzel <pmenzel@xxxxxxxxxxxxx> wrote: > > Dear Luiz, > > > Thank you for your patch. > > Am 09.09.24 um 22:51 schrieb Luiz Augusto von Dentz: > > From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> > > > > Requesting transfers of the exact same size of wMaxPacketSize may result > > in ZPL/short-transfer since the USB stack cannot handle it as we are > > limiting the buffer size to be the same as wMaxPacketSize. > > > > Also, in terms of throughput this change has the same effect to > > interrupt endpoint as 290ba200815f "Bluetooth: Improve USB driver throughput > > (*interrupt* would fit on the line above.) > > > by increasing the frame size" had for the bulk endpoint, so users of the > > advertisement bearer (e.g. BT Mesh) may benefit from this change. > > Do you have a benchmark script, that can be run? It is a **may** not a might and not the main objective of the change. > > Fixes: 5e23b923da03 ("[Bluetooth] Add generic driver for Bluetooth USB devices") > > Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> > > --- > > drivers/bluetooth/btusb.c | 5 ++++- > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c > > index 36a869a57910..83df387aea92 100644 > > --- a/drivers/bluetooth/btusb.c > > +++ b/drivers/bluetooth/btusb.c > > @@ -1341,7 +1341,10 @@ static int btusb_submit_intr_urb(struct hci_dev *hdev, gfp_t mem_flags) > > if (!urb) > > return -ENOMEM; > > > > - size = le16_to_cpu(data->intr_ep->wMaxPacketSize); > > + /* Use maximum HCI Event size so the USB stack handles > > + * ZPL/short-transfer automatically. > > + */ > > + size = HCI_MAX_EVENT_SIZE; > > > > buf = kmalloc(size, mem_flags); > > if (!buf) { > > > Kind regards, > > Paul > > Kind regards, > > Paul -- Luiz Augusto von Dentz