Re: [PATCH 12/23] e1000: Maybe stop TX if not enough free descriptors
From: Stephen Hemminger <hidden>
Date: 2006-09-19 20:59:40
From: Stephen Hemminger <hidden>
Date: 2006-09-19 20:59:40
On Tue, 19 Sep 2006 16:45:06 -0400 Jeff Garzik [off-list ref] wrote:
looks OK except for the tasklet, which may starve if the lock is being held upon entry
Why would the tasklet starve anymore than NAPI? Worst case, the transmitters fill the ring completely and have to wait for the tasklet to clean up. Maybe it would be better to always to Tx cleanup in tasklet even with NAPI. Then the NAPI poll flow control would be used only for Rx. As it stands, if receiver gets swamped, the poll doesn't get run often, so the transmitter cleanup doesn't get run. A tasklet has the advantage of eliminating the need for adapter->tx_queue_lock as well. Stephen Hemminger [off-list ref]