Message-ID: <20121011071226.3909.qmail@stuge.se>
Date: Thu, 11 Oct 2012 09:12:26 +0200
From: Peter Stuge <peter@stuge.se>
To: Xiaofan Chen <xiaofanc@gmail.com>
Cc: Henrik Rydberg <rydberg@euromail.se>, Hans de Goede <hdegoede@redhat.com>,
        Alan Stern <stern@rowland.harvard.edu>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: REGRESSION: usbdevfs:
	Use-scatter-gather-lists-for-large-bulk-transfers
Mail-Followup-To: Xiaofan Chen <xiaofanc@gmail.com>,
	Henrik Rydberg <rydberg@euromail.se>,
	Hans de Goede <hdegoede@redhat.com>,
	Alan Stern <stern@rowland.harvard.edu>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
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Xiaofan Chen wrote:
> On Thu, Oct 11, 2012 at 2:50 PM, Peter Stuge <peter@stuge.se> wrote:
> > But it isn't certain that is is involved at all. If your impact
> > version uses libusb.so like in ISE 11.1 then it will not be. One way
> > to test is by trying to generate a libusb debug log. See
> > https://libusb.org/wiki/debug for instructions which are for libusb,
> > but which work also for libusbx since the code is nearly the same.
> > (Just replace the repository to clone from.)
> 
> Actually this is not that correct. For libusbx, you do not need
> to rebuild libusbx to get the debug log at all, just need to
> set environment variable LIBUSB_DEBUG=4 to get the
> debug log.

The configure option to completely disable logging is still present
in libusbx, and I do not know which distributions use that, if any,
so I prefer to recommend the method that is guaranteed to work.


//Peter
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