[S390] add TIF_SYSCALL thread flag

Add an explicit TIF_SYSCALL bit that indicates if a task is inside
a system call. The svc_code in the pt_regs structure is now only
valid if TIF_SYSCALL is set. With this definition TIF_RESTART_SVC
can be replaced with TIF_SYSCALL. Overall do_signal is a bit more
readable and it saves a few lines of code.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index bae1cc49fe96..3519c99ae0c0 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -750,7 +750,7 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
                  * debugger stored an invalid system call number. Skip
                  * the system call and the system call restart handling.
                  */
-                regs->svc_code = 0;
+                clear_thread_flag(TIF_SYSCALL);
                 ret = -1;
         }