ionic: use netif_txq_maybe_stop() in ionic_tx()

Commit 061b9bedbe ("ionic: Rework Tx start/stop flow") replaced
ionic_maybe_stop_tx() with netif_txq_maybe_stop() to get the memory
barriers around the stop/start bits right, but did not cover the stop
in ionic_tx() added by commit 138506ab24 ("ionic: Check stop no
restart"). Convert the remaining site.

netif_txq_maybe_stop() requires the ring indexes to be updated before
it is invoked, so the post has to come first. But ring_dbell comes
from __netdev_tx_sent_queue(), which runs after that and reads the
stop bit, so it is not known in time to pass to ionic_txq_post(). Post
without the doorbell and ring it separately.

The stop condition is unchanged. The re-check only clears the stop bit
when space has become available, so the doorbell starvation fixed by
commit 138506ab24 ("ionic: Check stop no restart") cannot recur.

Fixes: 138506ab24 ("ionic: Check stop no restart")
Signed-off-by: Nikhil P. Rao <nikhil.rao@amd.com>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Link: https://patch.msgid.link/20260901055627.1373129-1-nikhil.rao@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Nikhil P. Rao 2026-09-01 05:56:27 +00:00 • committed by Jakub Kicinski
commit c91b4d6e5c