tools/perf/build: Fix non-existent build directory handling

Arnaldo reported that non-existent build directories were not
recognized  properly. The reason is readlink failure causing 'O'
to become empty.

Solve it by passing through the 'O' variable unmodified if
readlink fails.

Reported-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: David Ahern <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 5aa3d040bbf3fa17c9bbffce14b8a3a6a2da70be..91470449516694369b00838d23e393b133ed061f 100644 (file)
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -34,7 +34,7 @@ endif
 # Only pass canonical directory names as the output directory:
 #
 ifneq ($(O),)
-  FULL_O := $(shell readlink -f $(O))
+  FULL_O := $(shell readlink -f $(O) || echo $(O))
 endif
 
 define print_msg