[S390] entry[64].S improvements

Another round of cleanup for entry[64].S, in particular the program check
handler looks more reasonable now. The code size for the 31 bit kernel
has been reduced by 616 byte and by 528 byte for the 64 bit version.
Even better the code is a bit faster as well.

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

arch/s390/include/asm/lowcore.h

@@ -97,47 +97,52 @@ struct _lowcore {
 	__u32	gpregs_save_area[16];		/* 0x0180 */
 	__u32	cregs_save_area[16];		/* 0x01c0 */
 
+	/* Save areas. */
+	__u32	save_area_sync[8];		/* 0x0200 */
+	__u32	save_area_async[8];		/* 0x0220 */
+	__u32	save_area_restart[1];		/* 0x0240 */
+	__u8	pad_0x0244[0x0248-0x0244];	/* 0x0244 */
+
 	/* Return psws. */
-	__u32	save_area[16];			/* 0x0200 */
-	psw_t	return_psw;			/* 0x0240 */
-	psw_t	return_mcck_psw;		/* 0x0248 */
+	psw_t	return_psw;			/* 0x0248 */
+	psw_t	return_mcck_psw;		/* 0x0250 */
 
 	/* CPU time accounting values */
-	__u64	sync_enter_timer;		/* 0x0250 */
-	__u64	async_enter_timer;		/* 0x0258 */
-	__u64	mcck_enter_timer;		/* 0x0260 */
-	__u64	exit_timer;			/* 0x0268 */
-	__u64	user_timer;			/* 0x0270 */
-	__u64	system_timer;			/* 0x0278 */
-	__u64	steal_timer;			/* 0x0280 */
-	__u64	last_update_timer;		/* 0x0288 */
-	__u64	last_update_clock;		/* 0x0290 */
+	__u64	sync_enter_timer;		/* 0x0258 */
+	__u64	async_enter_timer;		/* 0x0260 */
+	__u64	mcck_enter_timer;		/* 0x0268 */
+	__u64	exit_timer;			/* 0x0270 */
+	__u64	user_timer;			/* 0x0278 */
+	__u64	system_timer;			/* 0x0280 */
+	__u64	steal_timer;			/* 0x0288 */
+	__u64	last_update_timer;		/* 0x0290 */
+	__u64	last_update_clock;		/* 0x0298 */
 
 	/* Current process. */
-	__u32	current_task;			/* 0x0298 */
-	__u32	thread_info;			/* 0x029c */
-	__u32	kernel_stack;			/* 0x02a0 */
+	__u32	current_task;			/* 0x02a0 */
+	__u32	thread_info;			/* 0x02a4 */
+	__u32	kernel_stack;			/* 0x02a8 */
 
 	/* Interrupt and panic stack. */
-	__u32	async_stack;			/* 0x02a4 */
-	__u32	panic_stack;			/* 0x02a8 */
+	__u32	async_stack;			/* 0x02ac */
+	__u32	panic_stack;			/* 0x02b0 */
 
 	/* Address space pointer. */
-	__u32	kernel_asce;			/* 0x02ac */
-	__u32	user_asce;			/* 0x02b0 */
-	__u32	current_pid;			/* 0x02b4 */
+	__u32	kernel_asce;			/* 0x02b4 */
+	__u32	user_asce;			/* 0x02b8 */
+	__u32	current_pid;			/* 0x02bc */
 
 	/* SMP info area */
-	__u32	cpu_nr;				/* 0x02b8 */
-	__u32	softirq_pending;		/* 0x02bc */
-	__u32	percpu_offset;			/* 0x02c0 */
-	__u32	ext_call_fast;			/* 0x02c4 */
-	__u64	int_clock;			/* 0x02c8 */
-	__u64	mcck_clock;			/* 0x02d0 */
-	__u64	clock_comparator;		/* 0x02d8 */
-	__u32	machine_flags;			/* 0x02e0 */
-	__u32	ftrace_func;			/* 0x02e4 */
-	__u8	pad_0x02e8[0x0300-0x02e8];	/* 0x02e8 */
+	__u32	cpu_nr;				/* 0x02c0 */
+	__u32	softirq_pending;		/* 0x02c4 */
+	__u32	percpu_offset;			/* 0x02c8 */
+	__u32	ext_call_fast;			/* 0x02cc */
+	__u64	int_clock;			/* 0x02d0 */
+	__u64	mcck_clock;			/* 0x02d8 */
+	__u64	clock_comparator;		/* 0x02e0 */
+	__u32	machine_flags;			/* 0x02e8 */
+	__u32	ftrace_func;			/* 0x02ec */
+	__u8	pad_0x02f8[0x0300-0x02f0];	/* 0x02f0 */
 
 	/* Interrupt response block */
 	__u8	irb[64];			/* 0x0300 */
@@ -229,57 +234,62 @@ struct _lowcore {
 	psw_t	mcck_new_psw;			/* 0x01e0 */
 	psw_t	io_new_psw;			/* 0x01f0 */
 
-	/* Entry/exit save area & return psws. */
-	__u64	save_area[16];			/* 0x0200 */
-	psw_t	return_psw;			/* 0x0280 */
-	psw_t	return_mcck_psw;		/* 0x0290 */
+	/* Save areas. */
+	__u64	save_area_sync[8];		/* 0x0200 */
+	__u64	save_area_async[8];		/* 0x0240 */
+	__u64	save_area_restart[1];		/* 0x0280 */
+	__u8	pad_0x0288[0x0290-0x0288];	/* 0x0288 */
+
+	/* Return psws. */
+	psw_t	return_psw;			/* 0x0290 */
+	psw_t	return_mcck_psw;		/* 0x02a0 */
 
 	/* CPU accounting and timing values. */
-	__u64	sync_enter_timer;		/* 0x02a0 */
-	__u64	async_enter_timer;		/* 0x02a8 */
-	__u64	mcck_enter_timer;		/* 0x02b0 */
-	__u64	exit_timer;			/* 0x02b8 */
-	__u64	user_timer;			/* 0x02c0 */
-	__u64	system_timer;			/* 0x02c8 */
-	__u64	steal_timer;			/* 0x02d0 */
-	__u64	last_update_timer;		/* 0x02d8 */
-	__u64	last_update_clock;		/* 0x02e0 */
+	__u64	sync_enter_timer;		/* 0x02b0 */
+	__u64	async_enter_timer;		/* 0x02b8 */
+	__u64	mcck_enter_timer;		/* 0x02c0 */
+	__u64	exit_timer;			/* 0x02c8 */
+	__u64	user_timer;			/* 0x02d0 */
+	__u64	system_timer;			/* 0x02d8 */
+	__u64	steal_timer;			/* 0x02e0 */
+	__u64	last_update_timer;		/* 0x02e8 */
+	__u64	last_update_clock;		/* 0x02f0 */
 
 	/* Current process. */
-	__u64	current_task;			/* 0x02e8 */
-	__u64	thread_info;			/* 0x02f0 */
-	__u64	kernel_stack;			/* 0x02f8 */
+	__u64	current_task;			/* 0x02f8 */
+	__u64	thread_info;			/* 0x0300 */
+	__u64	kernel_stack;			/* 0x0308 */
 
 	/* Interrupt and panic stack. */
-	__u64	async_stack;			/* 0x0300 */
-	__u64	panic_stack;			/* 0x0308 */
+	__u64	async_stack;			/* 0x0310 */
+	__u64	panic_stack;			/* 0x0318 */
 
 	/* Address space pointer. */
-	__u64	kernel_asce;			/* 0x0310 */
-	__u64	user_asce;			/* 0x0318 */
-	__u64	current_pid;			/* 0x0320 */
+	__u64	kernel_asce;			/* 0x0320 */
+	__u64	user_asce;			/* 0x0328 */
+	__u64	current_pid;			/* 0x0330 */
 
 	/* SMP info area */
-	__u32	cpu_nr;				/* 0x0328 */
-	__u32	softirq_pending;		/* 0x032c */
-	__u64	percpu_offset;			/* 0x0330 */
-	__u64	ext_call_fast;			/* 0x0338 */
-	__u64	int_clock;			/* 0x0340 */
-	__u64	mcck_clock;			/* 0x0348 */
-	__u64	clock_comparator;		/* 0x0350 */
-	__u64	vdso_per_cpu_data;		/* 0x0358 */
-	__u64	machine_flags;			/* 0x0360 */
-	__u64	ftrace_func;			/* 0x0368 */
-	__u64	gmap;				/* 0x0370 */
-	__u8	pad_0x0378[0x0380-0x0378];	/* 0x0378 */
+	__u32	cpu_nr;				/* 0x0338 */
+	__u32	softirq_pending;		/* 0x033c */
+	__u64	percpu_offset;			/* 0x0340 */
+	__u64	ext_call_fast;			/* 0x0348 */
+	__u64	int_clock;			/* 0x0350 */
+	__u64	mcck_clock;			/* 0x0358 */
+	__u64	clock_comparator;		/* 0x0360 */
+	__u64	vdso_per_cpu_data;		/* 0x0368 */
+	__u64	machine_flags;			/* 0x0370 */
+	__u64	ftrace_func;			/* 0x0378 */
+	__u64	gmap;				/* 0x0380 */
+	__u8	pad_0x0388[0x0400-0x0388];	/* 0x0388 */
 
 	/* Interrupt response block. */
-	__u8	irb[64];			/* 0x0380 */
+	__u8	irb[64];			/* 0x0400 */
 
 	/* Per cpu primary space access list */
-	__u32	paste[16];			/* 0x03c0 */
+	__u32	paste[16];			/* 0x0440 */
 
-	__u8	pad_0x0400[0x0e00-0x0400];	/* 0x0400 */
+	__u8	pad_0x0480[0x0e00-0x0480];	/* 0x0480 */
 
 	/*
 	 * 0xe00 contains the address of the IPL Parameter Information

arch/s390/kernel/asm-offsets.c

@@ -108,7 +108,9 @@ int main(void)
 	DEFINE(__LC_PGM_NEW_PSW, offsetof(struct _lowcore, program_new_psw));
 	DEFINE(__LC_MCK_NEW_PSW, offsetof(struct _lowcore, mcck_new_psw));
 	DEFINE(__LC_IO_NEW_PSW, offsetof(struct _lowcore, io_new_psw));
-	DEFINE(__LC_SAVE_AREA, offsetof(struct _lowcore, save_area));
+	DEFINE(__LC_SAVE_AREA_SYNC, offsetof(struct _lowcore, save_area_sync));
+	DEFINE(__LC_SAVE_AREA_ASYNC, offsetof(struct _lowcore, save_area_async));
+	DEFINE(__LC_SAVE_AREA_RESTART, offsetof(struct _lowcore, save_area_restart));
 	DEFINE(__LC_RETURN_PSW, offsetof(struct _lowcore, return_psw));
 	DEFINE(__LC_RETURN_MCCK_PSW, offsetof(struct _lowcore, return_mcck_psw));
 	DEFINE(__LC_SYNC_ENTER_TIMER, offsetof(struct _lowcore, sync_enter_timer));

arch/s390/kernel/base.S

@@ -33,7 +33,7 @@ s390_base_mcck_handler_fn:
 	.previous
 
 ENTRY(s390_base_ext_handler)
-	stmg	%r0,%r15,__LC_SAVE_AREA
+	stmg	%r0,%r15,__LC_SAVE_AREA_ASYNC
 	basr	%r13,0
 0:	aghi	%r15,-STACK_FRAME_OVERHEAD
 	larl	%r1,s390_base_ext_handler_fn
@@ -41,7 +41,7 @@ ENTRY(s390_base_ext_handler)
 	ltgr	%r1,%r1
 	jz	1f
 	basr	%r14,%r1
-1:	lmg	%r0,%r15,__LC_SAVE_AREA
+1:	lmg	%r0,%r15,__LC_SAVE_AREA_ASYNC
 	ni	__LC_EXT_OLD_PSW+1,0xfd	# clear wait state bit
 	lpswe	__LC_EXT_OLD_PSW
 
@@ -53,7 +53,7 @@ s390_base_ext_handler_fn:
 	.previous
 
 ENTRY(s390_base_pgm_handler)
-	stmg	%r0,%r15,__LC_SAVE_AREA
+	stmg	%r0,%r15,__LC_SAVE_AREA_SYNC
 	basr	%r13,0
 0:	aghi	%r15,-STACK_FRAME_OVERHEAD
 	larl	%r1,s390_base_pgm_handler_fn
@@ -61,7 +61,7 @@ ENTRY(s390_base_pgm_handler)
 	ltgr	%r1,%r1
 	jz	1f
 	basr	%r14,%r1
-	lmg	%r0,%r15,__LC_SAVE_AREA
+	lmg	%r0,%r15,__LC_SAVE_AREA_SYNC
 	lpswe	__LC_PGM_OLD_PSW
 1:	lpswe	disabled_wait_psw-0b(%r13)
 
@@ -142,7 +142,7 @@ s390_base_mcck_handler_fn:
 	.previous
 
 ENTRY(s390_base_ext_handler)
-	stm	%r0,%r15,__LC_SAVE_AREA
+	stm	%r0,%r15,__LC_SAVE_AREA_ASYNC
 	basr	%r13,0
 0:	ahi	%r15,-STACK_FRAME_OVERHEAD
 	l	%r1,2f-0b(%r13)
@@ -150,7 +150,7 @@ ENTRY(s390_base_ext_handler)
 	ltr	%r1,%r1
 	jz	1f
 	basr	%r14,%r1
-1:	lm	%r0,%r15,__LC_SAVE_AREA
+1:	lm	%r0,%r15,__LC_SAVE_AREA_ASYNC
 	ni	__LC_EXT_OLD_PSW+1,0xfd	# clear wait state bit
 	lpsw	__LC_EXT_OLD_PSW
 
@@ -164,7 +164,7 @@ s390_base_ext_handler_fn:
 	.previous
 
 ENTRY(s390_base_pgm_handler)
-	stm	%r0,%r15,__LC_SAVE_AREA
+	stm	%r0,%r15,__LC_SAVE_AREA_SYNC
 	basr	%r13,0
 0:	ahi	%r15,-STACK_FRAME_OVERHEAD
 	l	%r1,2f-0b(%r13)
@@ -172,7 +172,7 @@ ENTRY(s390_base_pgm_handler)
 	ltr	%r1,%r1
 	jz	1f
 	basr	%r14,%r1
-	lm	%r0,%r15,__LC_SAVE_AREA
+	lm	%r0,%r15,__LC_SAVE_AREA_SYNC
 	lpsw	__LC_PGM_OLD_PSW
 
 1:	lpsw	disabled_wait_psw-0b(%r13)

arch/s390/kernel/head.S

@@ -329,8 +329,8 @@ iplstart:
 #
 # reset files in VM reader
 #
-	stidp	__LC_SAVE_AREA		# store cpuid
-	tm	__LC_SAVE_AREA,0xff	# running VM ?
+	stidp	__LC_SAVE_AREA_SYNC	# store cpuid
+	tm	__LC_SAVE_AREA_SYNC,0xff# running VM ?
 	bno	.Lnoreset
 	la	%r2,.Lreset
 	lhi	%r3,26

arch/s390/kernel/reipl64.S

@@ -17,11 +17,11 @@
 #
 ENTRY(store_status)
 	/* Save register one and load save area base */
-	stg	%r1,__LC_SAVE_AREA+120(%r0)
+	stg	%r1,__LC_SAVE_AREA_RESTART
 	lghi	%r1,SAVE_AREA_BASE
 	/* General purpose registers */
 	stmg	%r0,%r15,__LC_GPREGS_SAVE_AREA-SAVE_AREA_BASE(%r1)
-	lg	%r2,__LC_SAVE_AREA+120(%r0)
+	lg	%r2,__LC_SAVE_AREA_RESTART
 	stg	%r2,__LC_GPREGS_SAVE_AREA-SAVE_AREA_BASE+8(%r1)
 	/* Control registers */
 	stctg	%c0,%c15,__LC_CREGS_SAVE_AREA-SAVE_AREA_BASE(%r1)

arch/s390/kernel/smp.c

@@ -654,7 +654,7 @@ int __cpuinit __cpu_up(unsigned int cpu)
 				     - sizeof(struct stack_frame));
 	memset(sf, 0, sizeof(struct stack_frame));
 	sf->gprs[9] = (unsigned long) sf;
-	cpu_lowcore->save_area[15] = (unsigned long) sf;
+	cpu_lowcore->gpregs_save_area[15] = (unsigned long) sf;
 	__ctl_store(cpu_lowcore->cregs_save_area, 0, 15);
 	atomic_inc(&init_mm.context.attach_count);
 	asm volatile(