[PATCH v16 13/18] arm64: syscall: Simplify el0_svc_common() syscall exit path

[Jinjie Ruan]

Remove the redundant nested conditional check within the system call
exit path of el0_svc_common() to streamline the exit sequence.

When entering this fast-path block, CONFIG_DEBUG_RSEQ is guaranteed to be
disabled. Under this constraint, the code logic inside the block becomes
completely identical to the evaluation performed within
syscall_exit_to_user_mode_work(). Therefore, invoking the inline helper
directly achieves full logical equivalence while eliminating duplicate
code nesting.

No functional changes.

Cc: Mark Rutland <mark.rutland at arm.com>
Cc: Will Deacon <will at kernel.org>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Ada Couprie Diaz <ada.coupriediaz at arm.com>
Signed-off-by: Jinjie Ruan <ruanjinjie at huawei.com>
---
 arch/arm64/kernel/syscall.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/arm64/kernel/syscall.c b/arch/arm64/kernel/syscall.c
index 5dd94bece929..74308b6df43b 100644
--- a/arch/arm64/kernel/syscall.c
+++ b/arch/arm64/kernel/syscall.c
@@ -121,9 +121,7 @@ static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr,
 	 * exit regardless, as the old entry assembly did.
 	 */
 	if (!(unlikely(flags & _TIF_SYSCALL_WORK)) && !IS_ENABLED(CONFIG_DEBUG_RSEQ)) {
-		flags = read_thread_flags();
-		if (unlikely(flags & _TIF_SYSCALL_EXIT_WORK) || flags & _TIF_SINGLESTEP)
-			syscall_exit_to_user_mode_work(regs);
+		syscall_exit_to_user_mode_work(regs);
 		return;
 	}
 
-- 
2.34.1