[PATCH] uml: redundant code removal from signal delivery

From: Bodo Stroesser <bstroesser@fujitsu-siemens.com>

Change the do_signal interface to eliminate its argument.  Also, remove the
calls from the system call handlers since they are redundant.  In all cases,
pending signals are checked for in the interrupt handler.

Temporarily, do_signal passes the current error to kern_do_signal.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/um/include/kern_util.h

@@ -29,7 +29,7 @@ extern int kernel_thread_proc(void *data);
 extern void syscall_segv(int sig);
 extern int current_pid(void);
 extern unsigned long alloc_stack(int order, int atomic);
-extern int do_signal(int error);
+extern int do_signal(void);
 extern int is_stack_fault(unsigned long sp);
 extern unsigned long segv(unsigned long address, unsigned long ip, 
 			  int is_write, int is_user, void *sc);

arch/um/kernel/process_kern.c

@@ -141,7 +141,7 @@ void *_switch_to(void *prev, void *next, void *last)
 void interrupt_end(void)
 {
 	if(need_resched()) schedule();
-	if(test_tsk_thread_flag(current, TIF_SIGPENDING)) do_signal(0);
+	if(test_tsk_thread_flag(current, TIF_SIGPENDING)) do_signal();
 }
 
 void release_thread(struct task_struct *task)

arch/um/kernel/signal_kern.c

@@ -159,9 +159,10 @@ static int kern_do_signal(struct pt_regs *regs, sigset_t *oldset, int error)
 	return(0);
 }
 
-int do_signal(int error)
+int do_signal(void)
 {
-	return(kern_do_signal(&current->thread.regs, NULL, error));
+	return(kern_do_signal(&current->thread.regs, NULL,
+			      PT_REGS_SYSCALL_RET(&current->thread.regs)));
 }
 
 /*

arch/um/kernel/skas/syscall_user.c

@@ -10,10 +10,6 @@
 #include "sysdep/ptrace.h"
 #include "sysdep/sigcontext.h"
 
-/* XXX Bogus */
-#define ERESTARTSYS	512
-#define ERESTARTNOINTR	513
-#define ERESTARTNOHAND	514
 
 void handle_syscall(union uml_pt_regs *regs)
 {
@@ -26,9 +22,6 @@ void handle_syscall(union uml_pt_regs *regs)
 	result = execute_syscall(regs);
 
 	REGS_SET_SYSCALL_RETURN(regs->skas.regs, result);
-	if((result == -ERESTARTNOHAND) || (result == -ERESTARTSYS) || 
-	   (result == -ERESTARTNOINTR))
-		do_signal(result);
 
 	syscall_trace(regs, 1);
 	record_syscall_end(index, result);

arch/um/kernel/tt/syscall_user.c

@@ -17,10 +17,6 @@
 #include "syscall_user.h"
 #include "tt.h"
 
-/* XXX Bogus */
-#define ERESTARTSYS	512
-#define ERESTARTNOINTR	513
-#define ERESTARTNOHAND	514
 
 void syscall_handler_tt(int sig, union uml_pt_regs *regs)
 {
@@ -42,9 +38,6 @@ void syscall_handler_tt(int sig, union uml_pt_regs *regs)
 	UPT_SC(regs) = sc;
 
 	SC_SET_SYSCALL_RETURN(sc, result);
-	if((result == -ERESTARTNOHAND) || (result == -ERESTARTSYS) || 
-	   (result == -ERESTARTNOINTR))
-		do_signal(result);
 
 	syscall_trace(regs, 1);
 	record_syscall_end(index, result);