[dpdk-dev] [PATCH 0/5] vhost: add missing barriers, remove useless volatiles
maxime.coquelin at redhat.com
Wed Dec 5 10:49:52 CET 2018
This series adds missing read barriers after reading avail index
for split ring and desc flags for packed ring.
Once that fixed, the casts to volatile are useless and so removed.
Also, it turns out that some descriptors prefetching are either
badly placed, or useless, last part of the series fixes that.
With the series applied, I get between 0 and 4% gain depending
on the benchmark (testpmd txonly/rxonly/io).
Thanks to Jason for reporting the missing read barriers.
Maxime Coquelin (5):
vhost: enforce avail index and desc read ordering
vhost: enforce desc flags and content read ordering
vhost: prefetch descriptor after the read barrier
vhost: remove useless prefetch for packed ring descriptor
vhost: remove useless casts to volatile
lib/librte_vhost/virtio_net.c | 32 ++++++++++++++++++++++++--------
1 file changed, 24 insertions(+), 8 deletions(-)
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