Re: [PATCH 08/19] arm64: introduce is_a32_task and is_a32_thread (for AArch32 compat)

From: Arnd Bergmann
Date: Tue Jun 21 2016 - 11:48:03 EST


On Tuesday, June 21, 2016 1:34:59 PM CEST Andreas Schwab wrote:
> "Zhangjian (Bamvor)" <bamvor.zhangjian@xxxxxxxxxx> writes:
>
> >> @@ -78,9 +79,9 @@
> >>
> >> #ifdef CONFIG_COMPAT
> >> #define TASK_SIZE_32 UL(0x100000000)
> >> -#define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \
> >> +#define TASK_SIZE (is_compat_task() ? \
> >> TASK_SIZE_32 : TASK_SIZE_64)
> >> -#define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \
> >> +#define TASK_SIZE_OF(tsk) (is_compat_thread(tsk) ? \
> > It should be
> > +#define TASK_SIZE_OF(tsk) (is_compat_thread(task_thread_info(tsk)) ? \
> > is_compat_thread takes "struct thread_info *thread" while TASK_SIZE_OF takes
> > "struct task_struct *tsk"tsk.
>
> If that doesn't throw an error does that mean that TASK_SIZE_OF is
> unused?

I think that is correct. On some architectures, TASK_SIZE (which is used)
is defined as TASK_SIZE_OF(current), but the definition above doesn't
do that and there are no other users.

Arnd