config = {
    'mock_target': 'mozilla-centos6-x86_64',
    'mock_packages': ['freetype-devel', 'fontconfig-devel', 'glib2-devel', 'autoconf213', 'git', 'make', 'libX11-devel', 'mesa-libGL-devel', 'freeglut-devel',
                      'xorg-x11-server-devel', 'libXrandr-devel', 'libXi-devel', 'libpng-devel', 'expat-devel'],
    'mock_files': [('/home/servobld/.ssh', '/home/mock_mozilla/.ssh')],
    'concurrency': 6,
    'add_actions': ['setup-mock'],
}

config = {
    'mock_target': 'mozilla-centos6-x86_64',
    'mock_packages': ['freetype-devel', 'fontconfig-devel', 'glib2-devel', 'autoconf213', 'git', 'make', 'libX11-devel', 'mesa-libGL-devel', 'freeglut-devel',
                      'xorg-x11-server-devel', 'libXrandr-devel', 'libXi-devel', 'libpng-devel', 'expat-devel', 'gperf'],
    'mock_files': [('/home/servobld/.ssh', '/home/mock_mozilla/.ssh')],
    'concurrency': 6,
    'add_actions': ['setup-mock'],
}

Install gperf on Linux builders
Install gperf on Linux builders
