This was a long-standing bug, relative pathnames like O=dir did not fully
work in the build system:
$ make O=localdir clean
SUBDIR Documentation
../../scripts/Makefile.include:3: *** O=localdir does not exist. Stop.
make[1]: *** [clean] Error 2
make: *** [clean] Error 2
Fix this by canonizing the directory before passing it to Makefile.perf.
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/n/tip-hchMp1hozn9tqgswWcooxcru@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
b102420b50