[RFC PATCH 03/13] arm64: ptrace: Always inline pt_regs_[read,write}_reg()

[Mark Rutland]

In subsequent patches we'll want to use pt_regs_read_reg() and
pt_regs_write_reg() in noinstr code.

To ensure noinstr safety, both functions must be inlined into their
caller. As both functions are marked as 'inline' rather than
'__always_inline', that's not strictly guaranteed, and the compiler is
permitted to generate out-of-line copies.

Mark both functions as '__always_inline' to ensure this.

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

Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Ada Couprie Diaz <ada.coupriediaz@xxxxxxx>
Cc: Ard Biesheuvel <ardb@xxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Jinjie Ruan <ruanjinjie@xxxxxxxxxx>
Cc: Marc Zyngier <maz@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Vladimir Murzin <vladimir.murzin@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Yang Shi <yang@xxxxxxxxxxxxxxxxxxxxxx>
---
 arch/arm64/include/asm/ptrace.h | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h
index 39582511ad72f..a1aa668aad50e 100644
--- a/arch/arm64/include/asm/ptrace.h
+++ b/arch/arm64/include/asm/ptrace.h
@@ -268,7 +268,8 @@ static inline u64 regs_get_register(struct pt_regs *regs, unsigned int offset)
  * Read a register given an architectural register index r.
  * This handles the common case where 31 means XZR, not SP.
  */
-static inline unsigned long pt_regs_read_reg(const struct pt_regs *regs, int r)
+static __always_inline unsigned long
+pt_regs_read_reg(const struct pt_regs *regs, int r)
 {
 	return (r == 31) ? 0 : regs->regs[r];
 }
@@ -277,8 +278,8 @@ static inline unsigned long pt_regs_read_reg(const struct pt_regs *regs, int r)
  * Write a register given an architectural register index r.
  * This handles the common case where 31 means XZR, not SP.
  */
-static inline void pt_regs_write_reg(struct pt_regs *regs, int r,
-				     unsigned long val)
+static __always_inline void
+pt_regs_write_reg(struct pt_regs *regs, int r, unsigned long val)
 {
 	if (r != 31)
 		regs->regs[r] = val;
-- 
2.30.2