[PATCH] arm64: Fix compile error seen in non-SMP builds

[Frederic Weisbecker]

On Fri, Oct 10, 2014 at 06:15:34PM -0700, Guenter Roeck wrote:
> Fix:
> 
> In file included from ./arch/arm64/include/asm/irq_work.h:4:0,
>         from include/linux/irq_work.h:46,
>         from include/linux/perf_event.h:49,
>         from include/linux/ftrace_event.h:9,
>         from include/trace/syscall.h:6,
>         from include/linux/syscalls.h:81,
>         from init/main.c:18:
> ./arch/arm64/include/asm/smp.h:24:3:
> 	error: #error "<asm/smp.h> included in non-SMP build"
>  # error "<asm/smp.h> included in non-SMP build"
>    ^
> ./arch/arm64/include/asm/smp.h:27:0: warning: "raw_smp_processor_id" redefined
>  #define raw_smp_processor_id() (current_thread_info()->cpu)
>  ^
> 
> and:
> 
> In file included from ./arch/arm64/include/asm/irq_work.h:4:0,
>         from include/linux/irq_work.h:46,
>         from kernel/irq_work.c:11:
> ./arch/arm64/include/asm/smp_plat.h:56:30:
>         error: ‘NR_CPUS’ undeclared here (not in a function)
>         extern u64 __cpu_logical_map[NR_CPUS];
> 
> by providing a helper function in smp_plat.h, similar to the arm implementation,
> and by removing NR_CPUS from smp_plat.h.
> 
> Fixes: 3631073659d0 ("arm64: Tell irq work about self IPI support")
> Cc: Frederic Weisbecker <fweisbec at gmail.com>
> Signed-off-by: Guenter Roeck <linux at roeck-us.net>

That looks good to me.

Note, ARM64 is one of the archs I couldn't test due to the lack of a
nolibc cross compiler in https://www.kernel.org/pub/tools/crosstool/

Thanks!