Show hhvm-perf version in PKB log (GoogleCloudPlatform#109)

Git clone hhvm-perf so that version can be found and displayed. Fall back to curl if git fails.

README.md

@@ -152,6 +152,10 @@ The path to these commands should be
 
 `C:\\Users\\\<user\>\\AppData\\Local\\GitHub\\PortableGit\_\<guid\>\\bin`
 
+## (*Linux Only*) Install git
+In most recent Linux distributions, git can be installed using the distribution's package manager. Please see the
+[Git Download page](https://git-scm.com/download/linux) for more information.
+
 ## Install PerfKit
 
 [Download PerfKit Benchmarker](http://github.com/GoogleCloudPlatform/PerfKitBenchmarker/releases) from GitHub.

perfkitbenchmarker/linux_packages/intel_hhvm_provisioning.py

@@ -6,7 +6,8 @@
 from perfkitbenchmarker import data, vm_util
 from perfkitbenchmarker.linux_packages import INSTALL_DIR
 
-HHVM_PERF_URL = ('https://github.intel.com/dslo/hhvm-perf/'
+HHVM_PERF_URL_GIT = ('https://github.intel.com/DSLO/hhvm-perf.git')
+HHVM_PERF_URL_CURL = ('https://github.intel.com/dslo/hhvm-perf/'
                  'archive/master.tar.gz')
 HHVM_PROV_URL = ('https://github.intel.com/dslo/hhvm_provisioning/'
                  'archive/master.tar.gz')
@@ -73,19 +74,25 @@ def Install(vm):
   if not onPrem(vm):
     # get hhvm-perf and copy to hhvm_provisioning dir structure
     perf_path = vm_util.PrependTempDir('hhvm-perf.tar.gz')
-    cmds = [['curl',
-            '-SL', '--noproxy', 'github.intel.com',
-             HHVM_PERF_URL,
-             '-o', perf_path],
-            # extract tarball so we can rename root dir to 'hhvm-perf'
-            ['tar', '-C', vm_util.GetTempDir(), '-xvf', perf_path],
-            ['mv', vm_util.PrependTempDir('hhvm-perf-master'),
-             vm_util.PrependTempDir('hhvm-perf')],
-            ['rm', '-r', perf_path]
-            ]
-    for cmd in cmds:
+    try:
+      vm_util.IssueCommand(['git',
+                            'clone',
+                            '--depth=1',
+                            HHVM_PERF_URL_GIT,
+                            vm_util.PrependTempDir('hhvm-perf')])
+    except:
+      cmds = [['curl',
+               '-SL', '--noproxy', 'github.intel.com',
+               HHVM_PERF_URL_CURL,
+               '-o', perf_path],
+               # extract tarball so we can rename root dir to 'hhvm-perf'
+               ['tar', '-C', vm_util.GetTempDir(), '-xvf', perf_path],
+               ['mv', vm_util.PrependTempDir('hhvm-perf-master'),
+               vm_util.PrependTempDir('hhvm-perf')],
+               ['rm', '-r', perf_path]
+             ]
+      for cmd in cmds:
         vm_util.IssueCommand(cmd)
-
     # set the cwd to 'tempdir' for this command so the tarball won't preserve
     # the entire dir structure
     vm_util.IssueCommand(['tar', '-czvf', perf_path, 'hhvm-perf'],