unwind_init() is currently a single function that initializes all of the
unwind state. Split it into the following functions and call them
appropriately:
- unwind_init_from_regs() - initialize from regs passed by caller.
- unwind_init_from_caller() - initialize for the current task
from the caller of arch_stack_walk().
- unwind_init_from_task() - initialize from the saved state of a
task other than the current task. In this case, the other
task must not be running.
This is done for two reasons:
- the different ways of initializing are clear
- specialized code can be added to each initializer in the future.
Signed-off-by: Madhavan T. Venkataraman <madvenka@linux.microsoft.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220617180219.20352-2-madvenka@linux.microsoft.com
Signed-off-by: Will Deacon <will@kernel.org>
a019d8a2cc