perf tools: Use getconf to determine number of online CPUs

Parsing /proc/cpuinfo is a fiddly, arch-dependent business and a recent
change to get it working for Sparc broke arm and arm64 platforms.

Use sysconf to determine the number of online CPUs only parsing
/proc/cpuinfo when sysconf is not available.

Signed-off-by: Will Deacon <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: David Ahern <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
[ Made it fall back to parsing /proc when getconf not found ]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index c699dc35eef9cbd1bc96427f453acc23a2e9c103..d31a7bbd7cee8610db236c7842cfb5ec63dc56b0 100644 (file)
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -24,7 +24,7 @@ unexport MAKEFLAGS
 # (To override it, run 'make JOBS=1' and similar.)
 #
 ifeq ($(JOBS),)
-  JOBS := $(shell egrep -c '^processor|^CPU' /proc/cpuinfo 2>/dev/null)
+  JOBS := $(shell (getconf _NPROCESSORS_ONLN || egrep -c '^processor|^CPU[0-9]' /proc/cpuinfo) 2>/dev/null)
   ifeq ($(JOBS),0)
     JOBS := 1
   endif