K 10
svn:author
V 2
np
K 8
svn:date
V 27
2020-08-26T23:21:26.454677Z
K 7
svn:log
V 1568
MFC r340023 (by jhb@), r362905, r362938, and r363167.

r340023:
Check cannot_use_txpkts() rather than needs_tso() in add_to_txpkts().

Currently this is a no-op, but will matter in the future when
cannot_use_txpkts() starts checking other conditions than just
needs_tso().

r362905:
cxgbe(4): changes in the Tx path to help increase tx coalescing.

- Ask the firmware for the number of frames that can be stuffed in one
  work request.

- Modify mp_ring to increase the likelihood of tx coalescing when there
  are just one or two threads that are doing most of the tx.  Add teeth
  to the abdication mechanism by pushing the consumer lock into mp_ring.
  This reduces the likelihood that a consumer will get stuck with all
  the work even though it is above its budget.

- Add support for coalesced tx WR to the VF driver.  This, with the
  changes above, results in a 7x improvement in the tx pps of the VF
  driver for some common cases.  The firmware vets the L2 headers
  submitted by the VF driver and it's a big win if the checks are
  performed for a batch of packets and not each one individually.

r362938:
cxgbe(4): Fix a bug (introduced in r362905) where some tx traffic wasn't
being reported to BPF.

r363167:
cxgbev(4): Compare at most 16 bytes of the Ethernet header when trying
to coalesce tx work requests.

Note that Coverity will still treat this as an out-of-bounds access.  We
do want to compare 16B starting from ethmacdst but cmp_l2hdr was was
going beyond that by 2B.

cmp_l2hdr was introduced in r362905.

Sponsored by:	Chelsio Communications

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