From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shirley Ma <mashirle@us.ibm.com>
Subject: [RFC PATCH 0/1] macvtap TX zero copy between guest and host kernel
Date: Mon, 13 Sep 2010 13:43:00 -0700
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Cc: xiaohui.xin@intel.com, netdev@vger.kernel.org, kvm@vger.kernel.org,
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To: Avi Kivity <avi@redhat.com>, Arnd Bergmann <arnd@arndb.de>,
	mst@redhat.com
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This patch induces a new sock flag ZEROCOPY to avoid copy between
userspace and kernel. macvtap is the first user of zero copy between
guest and host kernel. It only uses when the lower device supports high
memory DMA. The first set of patch only addresses transmission TX side.
The test has shown big improvement on either CPU utilization reduction
or BW increase on 10GbE Intel NIC. Performance data will be submitted in
the coming email.

thanks
Shirley