Re: [PATCH 2.6.25] - Fix transmit queue stop mechanism

From: Jeff Garzik
Date: Mon Mar 17 2008 - 08:09:38 EST


Divy Le Ray wrote:
From: Divy Le Ray <divy@xxxxxxxxxxx>

The last change in the Tx queue stop mechanism opens a window
where the Tx queue might be stopped after pending credits
returned.

Tx credits are returned via a control message generated by the HW.
It returns tx credits on demand, triggered by a completion bit
set in selective transmit packet headers.

The current code can lead to the Tx queue stopped
with all pending credits returned, and the current frame
not triggering a credit return. The Tx queue will then never be
awaken.

The driver could alternatively request a completion for packets
that stop the queue. It's however safer at this point to go back
to the pre-existing behaviour.

Signed-off-by: Divy Le Ray <divy@xxxxxxxxxxx>
---

drivers/net/cxgb3/sge.c | 12 +++++++++---
1 files changed, 9 insertions(+), 3 deletions(-)

applied -- please include "cxgb3: " prefix in your subject line next time.

See http://linux.yyz.us/patch-format.html for more info.

Jeff


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