Re: [PATCH -mm] x86_64 UP needs smp_call_function_single

From: Andrew Morton
Date: Wed Nov 29 2006 - 20:49:52 EST


On Wed, 29 Nov 2006 17:01:11 -0800
Randy Dunlap <randy.dunlap@xxxxxxxxxx> wrote:

> From: Randy Dunlap <randy.dunlap@xxxxxxxxxx>
>
> smp_call_function_single() needs to be visible in non-SMP builds, to fix:
>
> arch/x86_64/kernel/vsyscall.c:283: warning: implicit declaration of function 'smp_call_function_single'
>
> The (other/trivial) fix (instead of this one) is to add:
> #include <asm/smp.h>
> to linux-2.6.19-rc6-mm2/arch/x86_64/kernel/vsyscall.c
>
> Signed-off-by: Randy Dunlap <randy.dunlap@xxxxxxxxxx>
> ---
> include/asm-x86_64/smp.h | 7 -------
> include/linux/smp.h | 7 +++++++
> 2 files changed, 7 insertions(+), 7 deletions(-)
>
> --- linux-2.6.19-rc6-mm2.orig/include/asm-x86_64/smp.h
> +++ linux-2.6.19-rc6-mm2/include/asm-x86_64/smp.h
> @@ -113,13 +113,6 @@ static __inline int logical_smp_processo
> #define cpu_physical_id(cpu) x86_cpu_to_apicid[cpu]
> #else
> #define cpu_physical_id(cpu) boot_cpu_id
> -static inline int smp_call_function_single(int cpuid, void (*func) (void *info),
> - void *info, int retry, int wait)
> -{
> - /* Disable interrupts here? */
> - func(info);
> - return 0;
> -}
> #endif /* !CONFIG_SMP */
> #endif
>
> --- linux-2.6.19-rc6-mm2.orig/include/linux/smp.h
> +++ linux-2.6.19-rc6-mm2/include/linux/smp.h
> @@ -99,6 +99,13 @@ static inline int up_smp_call_function(v
> static inline void smp_send_reschedule(int cpu) { }
> #define num_booting_cpus() 1
> #define smp_prepare_boot_cpu() do {} while (0)
> +static inline int smp_call_function_single(int cpuid, void (*func) (void *info),
> + void *info, int retry, int wait)
> +{
> + /* Disable interrupts here? */
> + func(info);
> + return 0;
> +}
>
> #endif /* !SMP */
>

No, I think this patch is right - the declaration of the CONFIG_SMP
smp_call_function_single() is in linux/smp.h so the !CONFIG_SMP declaration
or definition should be there too.

It's still buggy though. It should disable local interrupts around the
call to match the SMP version. I'll fix that separately.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/