tree 2e2614e76451f733fe10091e568d438e87c23b79
parent 94d2dc6136b5a543b6268040b00924112ae9aae3
author Zach Johnson <zachoverflow@google.com> 1464827608 -0700
committer Zach Johnson <zachoverflow@google.com> 1464828172 -0700

Fix CpuThrottlingWaiter cat failures

Some devices can return multiple CPUs directories
on the same line when running ls to list the CPUs
on the device.

e.g.

/sys/devices/system/cpu/cpu0/cpufreq /sys/devices/system/cpu/cpu3/cpufreq
/sys/devices/system/cpu/cpu1/cpufreq /sys/devices/system/cpu/cpu4/cpufreq

CpuThrottlingWaiter splits the ls output by line
and feeds this into a cat command to get the
frequency to check if any cores are throttled.

e.g.

cat /sys/devices/system/cpu/cpu1/cpufreq /sys/devices/system/cpu/cpu4/cpufreq/cpuinfo_max_freq

When the cat command fails (trying to cat the
cpufreq directory), CpuThrottlingWaiter assumes
the device is throttled. And then does this until
it times out.

Fix this by telling the ls command to only output
one directory per line.

Change-Id: I27197d6ab8eb8767bb6903f197c5a650b3f26392