Re: arm/arm64 perf build issue with mainline

From: acme@xxxxxxxxxx
Date: Mon May 11 2015 - 12:00:21 EST

Em Mon, May 11, 2015 at 12:58:14PM -0300, acme@xxxxxxxxxx escreveu:
> Em Mon, May 11, 2015 at 02:33:04PM +0200, Ingo Molnar escreveu:
> > > That was already proposed here (as part of the fallback from getconf):
> > >
> > >
> > >
> > > but I'm not sure what happened to the patch.
> >
> > Sending out the latest/best version as a reminder for Arnaldo will
> > sure help it along.
> >
> > Acked-by: Ingo Molnar <mingo@xxxxxxxxxx>
> IIRC it was merged already, lemme check...

Yes, only for perf/core:

[acme@zoo linux]$ git show 762abdc0c6c013425958cd9f5105f4e32268d434
commit 762abdc0c6c013425958cd9f5105f4e32268d434
Author: Will Deacon <will.deacon@xxxxxxx>
Date: Thu Apr 23 15:00:16 2015 +0100

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 <will.deacon@xxxxxxx>
Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: David Ahern <david.ahern@xxxxxxxxxx>
Cc: Mark Rutland <Mark.Rutland@xxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
[ Made it fall back to parsing /proc when getconf not found ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index c699dc35eef9..d31a7bbd7cee 100644
--- 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
[acme@zoo linux]$
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