When one has libunwind installed somewhere the perf tools build process
doesn't expects it to be, this happens:
[acme@ssdandy linux]$ make O=/tmp/build/perf -C tools/perf/ install-bin
make: Entering directory `/home/acme/git/linux/tools/perf'
BUILD: Doing 'make -j8' parallel build
config/Makefile:312: No libunwind found, disabling post unwind support. Please install libunwind-dev[el] >= 1.1
Auto-detecting system features:
<SNIP>
... libunwind: [ OFF ]
Change the message so that it tells how to use a non-standard libunwind
install directory:
config/Makefile:312: No libunwind found, disabling post unwind support. Please install libunwind-dev[el] >= 1.1 and/or set LIBUNWIND_DIR
[acme@ssdandy linux]$ make LIBUNWIND_DIR=/opt/libunwind-git/ O=/tmp/build/perf -C tools/perf/ install-bin
make: Entering directory `/home/acme/git/linux/tools/perf'
BUILD: Doing 'make -j8' parallel build
Auto-detecting system features:
<SNIP>
... libunwind: [ on ]
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-huoxnou7sw85lm58k3pi1xhw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
7a0447d61d