Hi Herbert, On 04/28/2014 11:59 AM, Herbert Xu wrote: > On Mon, Apr 14, 2014 at 03:48:37PM +0300, Stanimir Varbanov wrote: >> >> +#define QCE_MAJOR_VERSION5 0x05 >> +#define QCE_QUEUE_LENGTH 50 > > What is the purpose of this software queue? Why can't you directly > feed the requests to the hardware?
Good question. This is a leftover from original driver. The hardware can handle one request at a time. After you raise the question I think the queue length should be 1 or remove it completely. I don't know why the original codeaurora's driver use 50. > > If the hardware can't handle more than 50 requests in-flight, > then your software queue has failed to handle this since you're > taking requests off the queue before you touch the hardware so > you're not really limiting it to 50. That is, for users that > can wait you're potentially dropping their requests instead > of letting them wait through the backlog mechanism. -- regards, Stan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
