[PATCH] USB: EHCI: fix for leaking isochronous data
From: Soeren Moch <hidden>
Date: 2013-03-15 00:00:18
Also in:
linux-mm, lkml
On 14.03.2013 22:33, Alan Stern wrote:
On Thu, 14 Mar 2013, Soeren Moch wrote:quoted
quoted
If the memory really is being leaked here in some sort of systematic way, we may be able to see it in your debugging output after a few seconds.OK, here are the first seconds of the log. But the buffer exhaustion usually occurs after several hours of runtime...The log shows a 1-1 match between allocations and deallocations, except for three excess allocations about 45 lines before the end. I have no idea what's up with those. They may be an artifact arising from where you stopped copying the log data. There are as many as 400 iTDs being allocated before any are freed. That seems like a lot. Are they all for the same isochronous endpoint? What's the endpoint's period? How often are URBs submitted?
I use 2 dvb sticks, capturing digital TV. For each stick 5 URBs on a single endpoint are used, I think. I'm not sure, which endpoint in which alternateSetting is active. I attached the output of 'lsusb -v' for the sticks. How can I track down the other information you need?
In general, there shouldn't be more than a couple of millisecond's worth of iTDs allocated for any endpoint, depending on how many URBs are in the pipeline at any time.
Maybe the em28xx driver is not doing a good job here!? Soeren Moch
Maybe a better way to go about this is, instead of printing out every allocation and deallocation, to keep a running counter. You could have the driver print out the value of this counter every minute or so. Any time the device isn't in use, the counter should be 0. Alan Stern
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Bus 001 Device 006: ID 2304:0242 Pinnacle Systems, Inc.
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