Re: stmmac ethernet in kernel 4.9-rc6: coalescing related pauses.

Hi!

quoted

quoted

In the ring, some descriptors can raise the irq (according to a
threshold) and set the IC bit. In this path, the NAPI  poll will be
scheduled.

Not NAPI poll but stmmac_tx_timer(), right?

in the xmit according the the threshold the timer is started or the
interrupt is set inside the descriptor.
Then stmmac_tx_clean will be always called and, if you see the flow,
no irqlock protection is needed!

Actually, I was wrong. irqlock protection is needed, since
stmmac_tx_clean() is called from timer, and that's interrupt context,
as you can confirm using BUG_ON(in_interrupt());

Best regards,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html