Re: arm/arm64 perf build issue with mainline

[Arnaldo Carvalho de Melo <acme@redhat.com>]

Em Mon, Apr 27, 2015 at 08:41:20PM +0200, Jiri Olsa escreveu:
> On Mon, Apr 27, 2015 at 03:39:53PM -0300, Arnaldo Carvalho de Melo wrote:
> > Em Mon, Apr 27, 2015 at 07:49:06PM +0200, Jiri Olsa escreveu:
> > > On Mon, Apr 27, 2015 at 02:40:17PM -0300, Arnaldo Carvalho de Melo wrote:
> > > > Em Mon, Apr 27, 2015 at 11:13:02AM -0600, David Ahern escreveu:
> > > > > 
> > > > > I think the right thing to do is to remove JOBS completely.
> > > > 
> > > > That is up for discussion, Ingo, Jiri, Namhyung, others?
> > > >  
> > > > > Barring that use of getconf with a fallback to grepping /proc/cpuinfo.
> > > > 
> > > > Ok, but no patch so far doing that, right? 8-)
> > > 
> > > heh, I've got the idea that you're preparing something ;-)
> > > 
> > > as for me I've got used to the automatic -jX being added,
> > > so I'd prefer we fix that JOBS setup for arm
> > > 
> > > I'll try to send something ;-)
> > 
> > [acme@ssdandy linux]$ (getconf _NPROCESSORS_ONLN || egrep -c '^processor|^CPU' /proc/cpuinfo) 2>/dev/null
> > 8
> > [acme@ssdandy linux]$ (not-found-getconf _NPROCESSORS_ONLN || egrep -c '^processor|^CPU' /proc/cpuinfo) 2>/dev/null
> > 8
> > [acme@ssdandy linux]$ 
> > 
> 
> how about this one

I came up with this one, that doesn't introduces a new file:

>From e8155c06652a05f2307d53823a7937be5dad4e32 Mon Sep 17 00:00:00 2001
From: Will Deacon <will.deacon@arm.com>
Date: Thu, 23 Apr 2015 15:00:16 +0100
Subject: [PATCH] tools perf: Use getconf to determine number of online CPUs

Parsing /proc/cpuinfo is a fiddly, arch-dependent business anda 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@arm.com>
Cc: David Ahern <david.ahern@oracle.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <Mark.Rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20150423140454.GJ1652@arm.com
[ Made it fall back to parsing /proc when getconf not found ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index c699dc35eef9..bc846b83c295 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 := $(shell (getconf _NPROCESSORS_ONLN || egrep -c '^processor|^CPU' /proc/cpuinfo) 2>/dev/null)
   ifeq ($(JOBS),0)
     JOBS := 1
   endif
-- 
1.8.3.1