From 352c1d95e3220d0ea33cefac5c1f0deb2c4470c6 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Sat, 22 Jun 2013 12:38:59 +0530 Subject: ARC: stop using pt_regs->orig_r8 Historically, pt_regs have had orig_r8, an overloaded container for (1) backup copy of r8 (syscall number Trap Exceptions) (2) additional system state: (syscall/Exception/Interrupt) There is no point in keeping (1) since syscall number is never clobbered in-place, in pt_regs, unlike r0 which duals as first syscall arg as well as syscall return value and in case of syscall restart, the orig arg0 needs restoring (from orig_r0) after having been updated in-place with syscall ret value. This further paves way to convert (2) to contain ECR itself (rather than current madeup values) Signed-off-by: Vineet Gupta --- arch/arc/include/asm/syscall.h | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'arch/arc/include/asm/syscall.h') diff --git a/arch/arc/include/asm/syscall.h b/arch/arc/include/asm/syscall.h index 33ab3048e9b2..29de09804306 100644 --- a/arch/arc/include/asm/syscall.h +++ b/arch/arc/include/asm/syscall.h @@ -18,7 +18,7 @@ static inline long syscall_get_nr(struct task_struct *task, struct pt_regs *regs) { if (user_mode(regs) && in_syscall(regs)) - return regs->orig_r8; + return regs->r8; else return -1; } @@ -26,8 +26,7 @@ syscall_get_nr(struct task_struct *task, struct pt_regs *regs) static inline void syscall_rollback(struct task_struct *task, struct pt_regs *regs) { - /* XXX: I can't fathom how pt_regs->r8 will be clobbered ? */ - regs->r8 = regs->orig_r8; + regs->r0 = regs->orig_r0; } static inline long -- cgit v1.2.3