[S390] cleanup trap handling

Move the program interruption code and the translation exception identifier to the pt_regs structure as 'int_code' and 'int_parm_long' and make the first level interrupt handler in entry[64].S store the two values. That makes it possible to drop 'prot_addr' and 'trap_no' from the thread_struct and to reduce the number of arguments to a lot of functions. Finally un-inline do_trap. Overall this saves 5812 bytes in the .text section of the 64 bit kernel. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
git-mirror · Dec 27, 2011 · aa33c8c · aa33c8c
1 parent 679e2ea
commit aa33c8c
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Showing 12 changed files with 158 additions and 210 deletions.
diff --git a/arch/s390/include/asm/kdebug.h b/arch/s390/include/asm/kdebug.h
@@ -22,6 +22,6 @@ enum die_val {
 	DIE_NMI_IPI,
 };
 
-extern void die(const char *, struct pt_regs *, long);
+extern void die(struct pt_regs *, const char *);
 
 #endif
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
@@ -80,8 +80,6 @@ struct thread_struct {
 	unsigned int  acrs[NUM_ACRS];
         unsigned long ksp;              /* kernel stack pointer             */
 	mm_segment_t mm_segment;
-        unsigned long prot_addr;        /* address of protection-excep.     */
-        unsigned int trap_no;
 	unsigned long gmap_addr;	/* address of last gmap fault. */
 	struct per_regs per_user;	/* User specified PER registers */
 	struct per_event per_event;	/* Cause of the last PER trap */

diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h
@@ -324,7 +324,8 @@ struct pt_regs
 	psw_t psw;
 	unsigned long gprs[NUM_GPRS];
 	unsigned long orig_gpr2;
-	unsigned int svc_code;
+	unsigned int int_code;
+	unsigned long int_parm_long;
 };
 
 /*

diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h
@@ -27,7 +27,7 @@ static inline long syscall_get_nr(struct task_struct *task,
 				  struct pt_regs *regs)
 {
 	return test_tsk_thread_flag(task, TIF_SYSCALL) ?
-		(regs->svc_code & 0xffff) : -1;
+		(regs->int_code & 0xffff) : -1;
 }
 
 static inline void syscall_rollback(struct task_struct *task,

diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c
@@ -45,7 +45,8 @@ int main(void)
 	DEFINE(__PT_PSW, offsetof(struct pt_regs, psw));
 	DEFINE(__PT_GPRS, offsetof(struct pt_regs, gprs));
 	DEFINE(__PT_ORIG_GPR2, offsetof(struct pt_regs, orig_gpr2));
-	DEFINE(__PT_SVC_CODE, offsetof(struct pt_regs, svc_code));
+	DEFINE(__PT_INT_CODE, offsetof(struct pt_regs, int_code));
+	DEFINE(__PT_INT_PARM_LONG, offsetof(struct pt_regs, int_parm_long));
 	DEFINE(__PT_SIZE, sizeof(struct pt_regs));
 	BLANK();
 	DEFINE(__SF_BACKCHAIN, offsetof(struct stack_frame, back_chain));

diff --git a/arch/s390/kernel/compat_signal.c b/arch/s390/kernel/compat_signal.c
@@ -501,8 +501,12 @@ static int setup_frame32(int sig, struct k_sigaction *ka,
 
 	/* We forgot to include these in the sigcontext.
 	   To avoid breaking binary compatibility, they are passed as args. */
-	regs->gprs[4] = current->thread.trap_no;
-	regs->gprs[5] = current->thread.prot_addr;
+	if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL ||
+	    sig == SIGTRAP || sig == SIGFPE) {
+		/* set extra registers only for synchronous signals */
+		regs->gprs[4] = regs->int_code & 127;
+		regs->gprs[5] = regs->int_parm_long;
+	}
 
 	/* Place signal number on stack to allow backtrace from handler.  */
 	if (__put_user(regs->gprs[2], (int __force __user *) &frame->signo))

diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
@@ -184,16 +184,16 @@ sysc_vtime:
 	stm	%r0,%r7,__PT_R0(%r11)
 	mvc	__PT_R8(32,%r11),__LC_SAVE_AREA_SYNC
 	mvc	__PT_PSW(8,%r11),__LC_SVC_OLD_PSW
-	mvc	__PT_SVC_CODE(4,%r11),__LC_SVC_ILC
+	mvc	__PT_INT_CODE(4,%r11),__LC_SVC_ILC
 sysc_do_svc:
 	oi	__TI_flags+3(%r12),_TIF_SYSCALL
-	lh	%r8,__PT_SVC_CODE+2(%r11)
+	lh	%r8,__PT_INT_CODE+2(%r11)
 	sla	%r8,2				# shift and test for svc0
 	jnz	sysc_nr_ok
 	# svc 0: system call number in %r1
 	cl	%r1,BASED(.Lnr_syscalls)
 	jnl	sysc_nr_ok
-	sth	%r1,__PT_SVC_CODE+2(%r11)
+	sth	%r1,__PT_INT_CODE+2(%r11)
 	lr	%r8,%r1
 	sla	%r8,2
 sysc_nr_ok:
@@ -266,9 +266,9 @@ sysc_sigpending:
 	jno	sysc_return
 	lm	%r2,%r7,__PT_R2(%r11)	# load svc arguments
 	xr	%r8,%r8			# svc 0 returns -ENOSYS
-	clc	__PT_SVC_CODE+2(2,%r11),BASED(.Lnr_syscalls+2)
+	clc	__PT_INT_CODE+2(2,%r11),BASED(.Lnr_syscalls+2)
 	jnl	sysc_nr_ok		# invalid svc number -> do svc 0
-	lh	%r8,__PT_SVC_CODE+2(%r11)	# load new svc number
+	lh	%r8,__PT_INT_CODE+2(%r11)	# load new svc number
 	sla	%r8,2
 	j	sysc_nr_ok		# restart svc
 
@@ -300,7 +300,7 @@ sysc_tracesys:
 	lr	%r2,%r11		# pass pointer to pt_regs
 	la	%r3,0
 	xr	%r0,%r0
-	icm	%r0,3,__PT_SVC_CODE+2(%r11)
+	icm	%r0,3,__PT_INT_CODE+2(%r11)
 	st	%r0,__PT_R2(%r11)
 	basr	%r14,%r1		# call do_syscall_trace_enter
 	cl	%r2,BASED(.Lnr_syscalls)
@@ -396,6 +396,8 @@ ENTRY(pgm_check_handler)
 	stm	%r0,%r7,__PT_R0(%r11)
 	mvc	__PT_R8(32,%r11),__LC_SAVE_AREA_SYNC
 	stm	%r8,%r9,__PT_PSW(%r11)
+	mvc	__PT_INT_CODE(4,%r11),__LC_PGM_ILC
+	mvc	__PT_INT_PARM_LONG(4,%r11),__LC_TRANS_EXC_CODE
 	tm	__LC_PGM_ILC+3,0x80	# check for per exception
 	jz	0f
 	l	%r1,__TI_task(%r12)
@@ -405,13 +407,11 @@ ENTRY(pgm_check_handler)
 	mvc	__THREAD_per_address(4,%r1),__LC_PER_ADDRESS
 	mvc	__THREAD_per_cause(2,%r1),__LC_PER_CAUSE
 	mvc	__THREAD_per_paid(1,%r1),__LC_PER_PAID
-0:	l	%r3,__LC_PGM_ILC	# load program interruption code
-	l	%r4,__LC_TRANS_EXC_CODE
-	REENABLE_IRQS
+0:	REENABLE_IRQS
 	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
 	l	%r1,BASED(.Ljump_table)
 	la	%r10,0x7f
-	nr	%r10,%r3
+	n	%r10,__PT_INT_CODE(%r11)
 	je	sysc_return
 	sll	%r10,2
 	l	%r1,0(%r10,%r1)		# load address of handler routine
@@ -858,7 +858,7 @@ cleanup_system_call:
 	mvc	__PT_R8(32,%r15),__LC_SAVE_AREA_SYNC
 	stm	%r0,%r7,__PT_R0(%r15)
 	mvc	__PT_PSW(8,%r15),__LC_SVC_OLD_PSW
-	mvc	__PT_SVC_CODE(4,%r15),__LC_SVC_ILC
+	mvc	__PT_INT_CODE(4,%r15),__LC_SVC_ILC
 	# setup saved register 15
 	ahi	%r15,-STACK_FRAME_OVERHEAD
 	st	%r15,28(%r11)		# r15 stack pointer

diff --git a/arch/s390/kernel/entry.h b/arch/s390/kernel/entry.h
@@ -6,15 +6,15 @@
 #include <asm/ptrace.h>
 
 
-extern void (*pgm_check_table[128])(struct pt_regs *, long, unsigned long);
+extern void (*pgm_check_table[128])(struct pt_regs *);
 extern void *restart_stack;
 
 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs);
 asmlinkage void do_syscall_trace_exit(struct pt_regs *regs);
 
-void do_protection_exception(struct pt_regs *, long, unsigned long);
-void do_dat_exception(struct pt_regs *, long, unsigned long);
-void do_asce_exception(struct pt_regs *, long, unsigned long);
+void do_protection_exception(struct pt_regs *regs);
+void do_dat_exception(struct pt_regs *regs);
+void do_asce_exception(struct pt_regs *regs);
 
 void do_per_trap(struct pt_regs *regs);
 void syscall_trace(struct pt_regs *regs, int entryexit);
@@ -28,7 +28,7 @@ void do_extint(struct pt_regs *regs, unsigned int, unsigned int, unsigned long);
 void do_restart(void);
 int __cpuinit start_secondary(void *cpuvoid);
 void __init startup_init(void);
-void die(const char * str, struct pt_regs * regs, long err);
+void die(struct pt_regs *regs, const char *str);
 
 void __init time_init(void);
 

diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
@@ -1,4 +1,3 @@
-
 /*
  *  arch/s390/kernel/entry64.S
  *    S390 low-level entry points.
@@ -200,17 +199,17 @@ sysc_vtime:
 	stmg	%r0,%r7,__PT_R0(%r11)
 	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
 	mvc	__PT_PSW(16,%r11),__LC_SVC_OLD_PSW
-	mvc	__PT_SVC_CODE(4,%r11),__LC_SVC_ILC
+	mvc	__PT_INT_CODE(4,%r11),__LC_SVC_ILC
 sysc_do_svc:
 	oi	__TI_flags+7(%r12),_TIF_SYSCALL
-	llgh	%r8,__PT_SVC_CODE+2(%r11)
+	llgh	%r8,__PT_INT_CODE+2(%r11)
 	slag	%r8,%r8,2			# shift and test for svc 0
 	jnz	sysc_nr_ok
 	# svc 0: system call number in %r1
 	llgfr	%r1,%r1				# clear high word in r1
 	cghi	%r1,NR_syscalls
 	jnl	sysc_nr_ok
-	sth	%r1,__PT_SVC_CODE+2(%r11)
+	sth	%r1,__PT_INT_CODE+2(%r11)
 	slag	%r8,%r1,2
 sysc_nr_ok:
 	larl	%r10,sys_call_table		# 64 bit system call table
@@ -288,7 +287,7 @@ sysc_sigpending:
 	jno	sysc_return
 	lmg	%r2,%r7,__PT_R2(%r11)	# load svc arguments
 	lghi	%r8,0			# svc 0 returns -ENOSYS
-	lh	%r1,__PT_SVC_CODE+2(%r11)	# load new svc number
+	lh	%r1,__PT_INT_CODE+2(%r11)	# load new svc number
 	cghi	%r1,NR_syscalls
 	jnl	sysc_nr_ok		# invalid svc number -> do svc 0
 	slag	%r8,%r1,2
@@ -318,7 +317,7 @@ sysc_singlestep:
 sysc_tracesys:
 	lgr	%r2,%r11		# pass pointer to pt_regs
 	la	%r3,0
-	llgh	%r0,__PT_SVC_CODE+2(%r11)
+	llgh	%r0,__PT_INT_CODE+2(%r11)
 	stg	%r0,__PT_R2(%r11)
 	brasl	%r14,do_syscall_trace_enter
 	lghi	%r0,NR_syscalls
@@ -411,6 +410,8 @@ ENTRY(pgm_check_handler)
 	stmg	%r0,%r7,__PT_R0(%r11)
 	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
 	stmg	%r8,%r9,__PT_PSW(%r11)
+	mvc	__PT_INT_CODE(4,%r11),__LC_PGM_ILC
+	mvc	__PT_INT_PARM_LONG(8,%r11),__LC_TRANS_EXC_CODE
 	stg	%r10,__PT_ARGS(%r11)
 	tm	__LC_PGM_ILC+3,0x80	# check for per exception
 	jz	0f
@@ -421,15 +422,13 @@ ENTRY(pgm_check_handler)
 	mvc	__THREAD_per_address(8,%r1),__LC_PER_ADDRESS
 	mvc	__THREAD_per_cause(2,%r1),__LC_PER_CAUSE
 	mvc	__THREAD_per_paid(1,%r1),__LC_PER_PAID
-0:	lgf	%r3,__LC_PGM_ILC	# load program interruption code
-	lg	%r4,__LC_TRANS_EXC_CODE
-	REENABLE_IRQS
+0:	REENABLE_IRQS
 	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
-	lghi	%r10,0x7f
-	ngr	%r10,%r3
-	je	sysc_return
-	sll	%r10,3
 	larl	%r1,pgm_check_table
+	llgh	%r10,__PT_INT_CODE+2(%r11)
+	nill	%r10,0x007f
+	sll	%r10,3
+	je	sysc_return
 	lg	%r1,0(%r10,%r1)		# load address of handler routine
 	lgr	%r2,%r11		# pass pointer to pt_regs
 	basr	%r14,%r1		# branch to interrupt-handler
@@ -877,7 +876,7 @@ cleanup_system_call:
 	mvc	__PT_R8(64,%r15),__LC_SAVE_AREA_SYNC
 	stmg	%r0,%r7,__PT_R0(%r15)
 	mvc	__PT_PSW(16,%r15),__LC_SVC_OLD_PSW
-	mvc	__PT_SVC_CODE(4,%r15),__LC_SVC_ILC
+	mvc	__PT_INT_CODE(4,%r15),__LC_SVC_ILC
 	# setup saved register r15
 	aghi	%r15,-STACK_FRAME_OVERHEAD
 	stg	%r15,56(%r11)		# r15 stack pointer

diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
@@ -302,9 +302,13 @@ static int setup_frame(int sig, struct k_sigaction *ka,
 
 	/* We forgot to include these in the sigcontext.
 	   To avoid breaking binary compatibility, they are passed as args. */
-	regs->gprs[4] = current->thread.trap_no;
-	regs->gprs[5] = current->thread.prot_addr;
-	regs->gprs[6] = task_thread_info(current)->last_break;
+	if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL ||
+	    sig == SIGTRAP || sig == SIGFPE) {
+		/* set extra registers only for synchronous signals */
+		regs->gprs[4] = regs->int_code & 127;
+		regs->gprs[5] = regs->int_parm_long;
+		regs->gprs[6] = task_thread_info(current)->last_break;
+	}
 
 	/* Place signal number on stack to allow backtrace from handler.  */
 	if (__put_user(regs->gprs[2], (int __user *) &frame->signo))
@@ -434,13 +438,13 @@ void do_signal(struct pt_regs *regs)
 	 * call information.
 	 */
 	current_thread_info()->system_call =
-		test_thread_flag(TIF_SYSCALL) ? regs->svc_code : 0;
+		test_thread_flag(TIF_SYSCALL) ? regs->int_code : 0;
 	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
 
 	if (signr > 0) {
 		/* Whee!  Actually deliver the signal.  */
 		if (current_thread_info()->system_call) {
-			regs->svc_code = current_thread_info()->system_call;
+			regs->int_code = current_thread_info()->system_call;
 			/* Check for system call restarting. */
 			switch (regs->gprs[2]) {
 			case -ERESTART_RESTARTBLOCK:
@@ -457,7 +461,7 @@ void do_signal(struct pt_regs *regs)
 				regs->gprs[2] = regs->orig_gpr2;
 				regs->psw.addr =
 					__rewind_psw(regs->psw,
-						     regs->svc_code >> 16);
+						     regs->int_code >> 16);
 				break;
 			}
 		}
@@ -488,11 +492,11 @@ void do_signal(struct pt_regs *regs)
 	/* No handlers present - check for system call restart */
 	clear_thread_flag(TIF_SYSCALL);
 	if (current_thread_info()->system_call) {
-		regs->svc_code = current_thread_info()->system_call;
+		regs->int_code = current_thread_info()->system_call;
 		switch (regs->gprs[2]) {
 		case -ERESTART_RESTARTBLOCK:
 			/* Restart with sys_restart_syscall */
-			regs->svc_code = __NR_restart_syscall;
+			regs->int_code = __NR_restart_syscall;
 		/* fallthrough */
 		case -ERESTARTNOHAND:
 		case -ERESTARTSYS: