arm64: percpu: Factor out percpu offset asm

Depending on whether the kernel runs at EL1 or EL2, the percpu offset is
stored in either TPIDR_EL1 or TPIDR_EL2, and __kern_my_cpu_offset() uses
an ALTERNATIVE() sequence to read the relevant TPIDR_ELx.

In subsequent patches we'll need to read the percpu offset in other
assembly sequences. Factor the ALTERNATIVE sequence out of
__kern_my_cpu_offset() into a new __KERN_ASM_CPU_OFFSET() macro so that
we can share the code sequence.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com>
Tested-by: Muhammad Usama Anjum <usama.anjum@arm.com>
Cc: Ada Couprie Diaz <ada.coupriediaz@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vladimir Murzin <vladimir.murzin@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yang Shi <yang@os.amperecomputing.com>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

0 files changed, 0 insertions, 0 deletions