Messages in this thread | | | Date | Fri, 16 Jan 2009 14:16:01 +0100 | From | Ingo Molnar <> | Subject | Re: [PATCH x86/percpu] x86_64: initialize this_cpu_off to __per_cpu_load |
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* Tejun Heo <htejun@gmail.com> wrote:
> On x86_64, if get_per_cpu_var() is used before per cpu area is setup > (if lockdep is turned on, it happens), it needs this_cpu_off to point > to __per_cpu_load. Initialize accordingly. > > Signed-off-by: Tejun Heo <tj@kernel.org> > --- > Okay, this fixes the problem. Tested with gcc-4.3.2 and binutils-2.19 > (openSUSE 11.1). For all four variants I can test (64-smp, 64-up, > 32-smp, 32-up). This and the previous merge fix patch are available > in the following git branch.
cool!
> git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git tj-percpu > > arch/x86/kernel/smpcommon.c | 5 +++++ > 1 files changed, 5 insertions(+), 0 deletions(-) > > diff --git a/arch/x86/kernel/smpcommon.c b/arch/x86/kernel/smpcommon.c > index 84395fa..7e15781 100644 > --- a/arch/x86/kernel/smpcommon.c > +++ b/arch/x86/kernel/smpcommon.c > @@ -3,8 +3,13 @@ > */ > #include <linux/module.h> > #include <asm/smp.h> > +#include <asm/sections.h> > > +#ifdef CONFIG_X86_64 > +DEFINE_PER_CPU(unsigned long, this_cpu_off) = (unsigned long)__per_cpu_load; > +#else > DEFINE_PER_CPU(unsigned long, this_cpu_off); > +#endif
I've pulled your tree, but couldnt we do this symmetrically in the 32-bit case too and avoid the ugly #ifdef somehow?
Ingo
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