[dts] [PATCH V3] tests: add test for vhost/virtio loopback performance

[Liu, Yong]

Lei, one comment remaining.

> -----Original Message-----
> From: dts [mailto:dts-bounces at dpdk.org] On Behalf Of lei,yao
> Sent: Thursday, December 29, 2016 1:10 PM
> To: dts at dpdk.org
> Cc: Yao, Lei A
> Subject: [dts] [PATCH V3] tests: add test for vhost/virtio loopback
> performance
> 
> From: lei yao <lei.a.yao at intel.com>
> 
> This test won't use qemu, but will use two testpmd thread to launch vhost-
> user and
> virtio-user to simulate the qemu user case.
> 
> Signed-off-by: lei yao <lei.a.yao at intel.com>
> ---
> +        # Get the default TX packet size of the testpmd
> +        file_path = "/root/dpdk/app/test-pmd/testpmd.h"
> +        fp = open(file_path, 'r')
> +        out = fp.read()
> +        search_result = re.search("TXONLY_DEF_PACKET_LEN\s*(\d*)", out)
> +        self.packet_length = search_result.group(1)
> +

We can't assume that dut and tester are using same server and DPDK folder maybe changed by input parameter.
You can do the same thing by some code like below:

	out = self.dut.send_expect("cat app/test-pmd/testpmd.h |grep TXONLY_DEF_PACKET_LEN", "# ")
	try:
		search_result = re.search("#define TXONLY_DEF_PACKET_LEN\s*(\d*)", out)
		self.packet_length = search_result.group(1)
	except:
		self.logger.error("Failed to capture default testpmd txonly packet length")