make profile issue on Git 2.1.0

Hi,

I have the following issue on Git 2.1.0:

$ make prefix=/some-directory profile ... make[2]: Entering directory `/home/asr/src/git/git-2.1.0/t/perf' rm -rf test-results ./run === Running 9 tests in this tree === error: No $GIT_PERF_REPO defined, and your build directory is not a repo error: No $GIT_PERF_REPO defined, and your build directory is not a repo error: No $GIT_PERF_REPO defined, and your build directory is not a repo error: No $GIT_PERF_REPO defined, and your build directory is not a repo error: No $GIT_PERF_REPO defined, and your build directory is not a repo error: No $GIT_PERF_REPO defined, and your build directory is not a repo error: No $GIT_PERF_REPO defined, and your build directory is not a repo error: No $GIT_PERF_REPO defined, and your build directory is not a repo error: No $GIT_PERF_REPO defined, and your build directory is not a repo cannot open test-results/p0000-perf-lib-sanity.subtests: No such file or directory at ./aggregate.perl line 77. make[2]: *** [perf] Error 2

I hadn't issues running the same command on Git 2.0.2.

Thanks,