Re: [tip:x86/xen] x86: use flush_tlb_others to implement flush_tlb_all, fix

Ian Campbell
2009-05-11T16:00:01Z

On Mon, 2009-05-11 at 11:42 -0400, Ingo Molnar wrote:
> * Ian Campbell <Ian.Campbell@eu.citrix.com> wrote:
>
> > in any case I would guess that the fix is:
> >
> > --- a/arch/x86/kernel/setup.c
> > +++ b/arch/x86/kernel/setup.c
> > @@ -87,6 +87,7 @@
> > #include <asm/cacheflush.h>
> > #include <asm/processor.h>
> > #include <asm/bugs.h>
> > +#include <asm/tlbflush.h>
> >
> > #include <asm/system.h>
> > #include <asm/vsyscall.h>
>
> Guessing is not enough - please review the prototype position. Is it
> available on all configs? It is not ...

Damn, you are (of course) right. There is nothing for it to do on !SMP
so patch below. I also observe that since it's no longer an initcall
there is no need for a return value so included that change too.

> But even the proper fix runs into that smp_processor_id() bug i just
> posted.

That's back to an issue in the original patch from Jeremy I think, I'll
leave that one to him and/or tomorrow -- I've botched enough patches for
one day!

Ian.

diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h
index a3f42bf..e1e3e6a 100644
--- a/arch/x86/include/asm/tlbflush.h
+++ b/arch/x86/include/asm/tlbflush.h
@@ -89,6 +89,8 @@ static inline void __flush_tlb_one(unsigned long addr)

#ifndef CONFIG_SMP

+static inline void init_smp_flush(void) {}
+
#define flush_tlb() __flush_tlb()
#define flush_tlb_all() __flush_tlb_all()
#define local_flush_tlb() __flush_tlb()
@@ -129,7 +131,7 @@ static inline void reset_lazy_tlbstate(void)

#define local_flush_tlb() __flush_tlb()

-extern int init_smp_flush(void);
+extern void init_smp_flush(void);

extern void flush_tlb_all(void);
extern void flush_tlb_current_task(void);
diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index 03f52f5..db28919 100644
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -217,14 +217,12 @@ void native_flush_tlb_others(const struct cpumask *cpumask,
flush_tlb_others_ipi(cpumask, mm, va);
}

-int __init init_smp_flush(void)
+void __init init_smp_flush(void)
{
int i;

for (i = 0; i < ARRAY_SIZE(flush_state); i++)
spin_lock_init(&flush_state[i].tlbstate_lock);
-
- return 0;
}

void flush_tlb_current_task(void)