[PATCH v3 21/21] arm64: percpu: Remove _pcp_protect*() wrappers

[Mark Rutland <mark.rutland@arm.com>]

Now that all this_cpu_*() operations are preemptible, there are no users
of _pcp_protect() or _pcp_protect_return().

Remove them both, along with the associated comment regarding
preemption.

Signed-off-by: Mark Rutland <mark.rutland@arm.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: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Jinjie Ruan <ruanjinjie@huawei.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>
---
 arch/arm64/include/asm/percpu.h | 27 ---------------------------
 1 file changed, 27 deletions(-)

diff --git a/arch/arm64/include/asm/percpu.h b/arch/arm64/include/asm/percpu.h
index 5cd98e20e825d..6ec6e212932d3 100644
--- a/arch/arm64/include/asm/percpu.h
+++ b/arch/arm64/include/asm/percpu.h
@@ -368,33 +368,6 @@ PERCPU_CMPXCHG_OP(x,  , 64)
 #undef PERCPU_XCHG_OP
 #undef PERCPU_CMPXCHG_OP
 
-/*
- * It would be nice to avoid the conditional call into the scheduler when
- * re-enabling preemption for preemptible kernels, but doing that in a way
- * which builds inside a module would mean messing directly with the preempt
- * count. If you do this, peterz and tglx will hunt you down.
- *
- * Not to mention it'll break the actual preemption model for missing a
- * preemption point when TIF_NEED_RESCHED gets set while preemption is
- * disabled.
- */
-
-#define _pcp_protect(op, pcp, ...)					\
-({									\
-	preempt_disable_notrace();					\
-	op(raw_cpu_ptr(&(pcp)), __VA_ARGS__);				\
-	preempt_enable_notrace();					\
-})
-
-#define _pcp_protect_return(op, pcp, args...)				\
-({									\
-	typeof(pcp) __retval;						\
-	preempt_disable_notrace();					\
-	__retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args);	\
-	preempt_enable_notrace();					\
-	__retval;							\
-})
-
 #define _pcp_wrap(op, pcp, ...)						\
 ({									\
 	op(&(pcp), __VA_ARGS__);					\
-- 
2.30.2