[PATCH 4/5] arm: enable support for software perf events

[Russell King - ARM Linux]

On Tue, Feb 02, 2010 at 06:48:31PM +0000, Jamie Iles wrote:
> On Tue, Feb 02, 2010 at 05:40:00PM +0000, Russell King - ARM Linux wrote:
> > On Thu, Jan 14, 2010 at 12:14:15PM +0000, Jamie Iles wrote:
> > > The perf events subsystem allows counting of both hardware and
> > > software events. This patch implements the bare minimum for software
> > > performance events.
> > > 
> > > Signed-off-by: Jamie Iles <jamie.iles at picochip.com>
> > > Cc: Peter Zijlstra <peterz at infradead.org>
> > > Cc: Ingo Molnar <mingo at elte.hu>
> > > ---
> > >  arch/arm/Kconfig                  |    2 ++
> > >  arch/arm/include/asm/perf_event.h |   31 +++++++++++++++++++++++++++++++
> > >  arch/arm/mm/fault.c               |    7 +++++++
> > >  3 files changed, 40 insertions(+), 0 deletions(-)
> > >  create mode 100644 arch/arm/include/asm/perf_event.h
> > > 
> > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> > > index 293a879..72646b2 100644
> > > --- a/arch/arm/Kconfig
> > > +++ b/arch/arm/Kconfig
> > > @@ -21,6 +21,8 @@ config ARM
> > >  	select HAVE_KERNEL_GZIP
> > >  	select HAVE_KERNEL_LZO
> > >  	select GENERIC_ATOMIC64
> > 
> > This conflicts - this select is only if !CPU_32v6K in my kernel.
> > 
> > What's the implication?  Does this perf stuff require these atomic64
> > stuff (in which case, those symbols should only be selected if
> > GENERIC_ATOMIC64 is also selected.)
> > 
> > Please sort this out.
> As Will mentioned, the correct case should be 'GENERIC_ATOMIC64 if
> (!CPU_32v6K)' due to my patches being off a tree without the native
> atomic64's. I can rebase onto next if that's easier.

Much prefer having them rebased onto 7558b1f, which is in -next if you
can manage that.

The better solution (which I think I'll do just before the merge window)
is to re-order the 'select' statements to be alphabetic, which should
help separate some of these conflicts.