Re: [PATCH 09/12] net: mediatek: increase watchdog_timeo
From: John Crispin <john@phrozen.org>
Date: 2016-06-06 06:24:24
Also in:
linux-mediatek, lkml
From: John Crispin <john@phrozen.org>
Date: 2016-06-06 06:24:24
Also in:
linux-mediatek, lkml
On 05/06/2016 16:56, Andrew Lunn wrote:
On Sun, Jun 05, 2016 at 08:33:02AM +0200, John Crispin wrote:quoted
During stress testing, after reducing the threshold value, we have seen TX timeouts that were caused by the watchdog_timeo value being too low. Increase the value to 5 * HZ which is a value commonly used by many other drivers.I've never studied what watchdog_timeo actually means. Does it mean a transmit has not completed in that amount of time? Would this imply you have 5 seconds worth of packets in your transmit queue? Do you know what the driver is doing during this 5 seconds?
Hi Andrew, it is waiting for the watchdog to trigger :-) TBH the 1s seems to be too short to for the dma ring length to be flushed and i had to pick some value and 5 is used most places. it really depends on the amount of packets in the queue, their length and the mac setting. the timeout needs to be large enough that it would not trigger incorrectly even if the mac is on 10mbit half duplex and all frames in the queue were maximum size. John