Commit cb3a86c8 authored by Paul Mundt's avatar Paul Mundt
Browse files

sh: Kill off sh64's hand-rolled syscall tracer. 



This is no longer necessary, as there are now sufficient generic
alternatives available.

Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
parent 1af2fe45

arch/sh/Kconfig.debug

+0 −8
Original line number Diff line number Diff line
@@ -137,12 +137,4 @@ config SH64_SR_WATCH 
	bool "Debug: set SR.WATCH to enable hardware watchpoints and trace"

	depends on SUPERH64



config POOR_MANS_STRACE

	bool "Debug: enable rudimentary strace facility"

	depends on SUPERH64

	help

	  This option allows system calls to be traced to the console.  It also

	  aids in detecting kernel stack underflow.  It is useful for debugging

	  early-userland problems (e.g. init incurring fatal exceptions.)



endmenu

arch/sh/Makefile

+2 −32
Original line number Diff line number Diff line
@@ -193,7 +193,7 @@ zImage uImage uImage.srec vmlinux.srec: vmlinux 


compressed: zImage



archprepare: maketools arch/sh/lib64/syscalltab.h

archprepare: maketools



archclean:

	$(Q)$(MAKE) $(clean)=$(boot)
@@ -205,34 +205,4 @@ define archhelp 
	@echo '  uImage.srec  	           - Create an S-record for U-Boot'

endef



define filechk_gen-syscalltab

       (set -e; \

	echo "/*"; \

	echo " * DO NOT MODIFY."; \

	echo " *"; \

	echo " * This file was generated by arch/sh/Makefile"; \

	echo " * Any changes will be reverted at build time."; \

	echo " */"; \

	echo ""; \

	echo "#ifndef __SYSCALLTAB_H"; \

	echo "#define __SYSCALLTAB_H"; \

	echo ""; \

	echo "#include <linux/kernel.h>"; \

	echo ""; \

	echo "struct syscall_info {"; \

	echo "	const char *name;"; \

	echo "} syscall_info_table[] = {"; \

	sed -e '/^.*\.long /!d;s//	{ "/;s/\(\([^/]*\)\/\)\{1\}.*/\2/; \

		s/[ \t]*$$//g;s/$$/" },/;s/\("\)sys_/\1/g'; \

	echo "};"; \

	echo ""; \

	echo "#define NUM_SYSCALL_INFO_ENTRIES ARRAY_SIZE(syscall_info_table)";\

	echo ""; \

	echo "#endif /* __SYSCALLTAB_H */" )

endef



arch/sh/lib64/syscalltab.h: arch/sh/kernel/syscalls_64.S

	$(call filechk,gen-syscalltab)



CLEAN_FILES += arch/sh/lib64/syscalltab.h \

	       include/asm-sh/machtypes.h
 
CLEAN_FILES += include/asm-sh/machtypes.h

arch/sh/kernel/cpu/sh5/entry.S

+0 −57
Original line number Diff line number Diff line
@@ -812,27 +812,6 @@ no_underflow: 
	! exceptions

	add	SP, ZERO, r14



#ifdef CONFIG_POOR_MANS_STRACE

	/* We've pushed all the registers now, so only r2-r4 hold anything

	 * useful. Move them into callee save registers */

	or	r2, ZERO, r28

	or	r3, ZERO, r29

	or	r4, ZERO, r30



	/* Preserve r2 as the event code */

	movi	evt_debug, r3

	ori	r3, 1, r3

	ptabs	r3, tr0



	or	SP, ZERO, r6

	getcon	TRA, r5

	blink	tr0, LINK



	or	r28, ZERO, r2

	or	r29, ZERO, r3

	or	r30, ZERO, r4

#endif



	/* For syscall and debug race condition, get TRA now */

	getcon	TRA, r5
@@ -887,11 +866,6 @@ no_underflow: 
 */

	.global ret_from_irq

ret_from_irq:

#ifdef CONFIG_POOR_MANS_STRACE

	pta	evt_debug_ret_from_irq, tr0

	ori	SP, 0, r2

	blink	tr0, LINK

#endif

	ld.q	SP, FRAME_S(FSSR), r6

	shlri	r6, 30, r6

	andi	r6, 1, r6
@@ -905,12 +879,6 @@ ret_from_irq: 
ret_from_exception:

	preempt_stop()



#ifdef CONFIG_POOR_MANS_STRACE

	pta	evt_debug_ret_from_exc, tr0

	ori	SP, 0, r2

	blink	tr0, LINK

#endif



	ld.q	SP, FRAME_S(FSSR), r6

	shlri	r6, 30, r6

	andi	r6, 1, r6
@@ -1236,18 +1204,6 @@ syscall_bad: 
	.global syscall_ret

syscall_ret:

	st.q	SP, FRAME_R(9), r2	/* Expecting SP back to BASIC frame */



#ifdef CONFIG_POOR_MANS_STRACE

	/* nothing useful in registers at this point */



	movi	evt_debug2, r5

	ori	r5, 1, r5

	ptabs	r5, tr0

	ld.q	SP, FRAME_R(9), r2

	or	SP, ZERO, r3

	blink	tr0, LINK

#endif



	ld.q	SP, FRAME_S(FSPC), r2

	addi	r2, 4, r2		/* Move PC, being pre-execution event */

	st.q	SP, FRAME_S(FSPC), r2
@@ -1268,25 +1224,12 @@ ret_from_fork: 
	ptabs	r5, tr0

	blink	tr0, LINK



#ifdef CONFIG_POOR_MANS_STRACE

	/* nothing useful in registers at this point */



	movi	evt_debug2, r5

	ori	r5, 1, r5

	ptabs	r5, tr0

	ld.q	SP, FRAME_R(9), r2

	or	SP, ZERO, r3

	blink	tr0, LINK

#endif



	ld.q	SP, FRAME_S(FSPC), r2

	addi	r2, 4, r2		/* Move PC, being pre-execution event */

	st.q	SP, FRAME_S(FSPC), r2

	pta	ret_from_syscall, tr0

	blink	tr0, ZERO







syscall_allowed:

	/* Use LINK to deflect the exit point, default is syscall_ret */

	pta	syscall_ret, tr0

arch/sh/lib64/.gitignore

deleted100644 → 0
+0 −1
Original line number Diff line number Diff line 
syscalltab.h

arch/sh/lib64/dbg.c

+0 −134
Original line number Diff line number Diff line
@@ -135,140 +135,6 @@ void print_itlb(void) 
	    (" =============================================================\n");

}



/* ======================================================================= */



#ifdef CONFIG_POOR_MANS_STRACE



#include "syscalltab.h"



struct ring_node {

	int evt;

	int ret_addr;

	int event;

	int tra;

	int pid;

	unsigned long sp;

	unsigned long pc;

};



static struct ring_node event_ring[16];

static int event_ptr = 0;



struct stored_syscall_data {

	int pid;

	int syscall_number;

};



#define N_STORED_SYSCALLS 16



static struct stored_syscall_data stored_syscalls[N_STORED_SYSCALLS];

static int syscall_next=0;

static int syscall_next_print=0;



void evt_debug(int evt, int ret_addr, int event, int tra, struct pt_regs *regs)

{

	int syscallno = tra & 0xff;

	unsigned long sp;

	unsigned long stack_bottom;

	int pid;

	struct ring_node *rr;



	pid = current->pid;

	stack_bottom = (unsigned long) task_stack_page(current);

	asm volatile("ori r15, 0, %0" : "=r" (sp));

	rr = event_ring + event_ptr;

	rr->evt = evt;

	rr->ret_addr = ret_addr;

	rr->event = event;

	rr->tra = tra;

	rr->pid = pid;

	rr->sp = sp;

	rr->pc = regs->pc;



	if (sp < stack_bottom + 3092) {

		int i, j;

		printk("evt_debug : stack underflow report\n");

		for (j=0, i = event_ptr; j<16; j++) {

			rr = event_ring + i;

			printk("evt=%08x event=%08x tra=%08x pid=%5d sp=%08lx pc=%08lx\n",

				rr->evt, rr->event, rr->tra, rr->pid, rr->sp, rr->pc);

			i--;

			i &= 15;

		}

		panic("STACK UNDERFLOW\n");

	}



	event_ptr = (event_ptr + 1) & 15;



	if ((event == 2) && (evt == 0x160)) {

		if (syscallno < NUM_SYSCALL_INFO_ENTRIES) {

			/* Store the syscall information to print later.  We

			 * can't print this now - currently we're running with

			 * SR.BL=1, so we can't take a tlbmiss (which could occur

			 * in the console drivers under printk).

			 *

			 * Just overwrite old entries on ring overflow - this

			 * is only for last-hope debugging. */

			stored_syscalls[syscall_next].pid = current->pid;

			stored_syscalls[syscall_next].syscall_number = syscallno;

			syscall_next++;

			syscall_next &= (N_STORED_SYSCALLS - 1);

		}

	}

}



static void drain_syscalls(void) {

	while (syscall_next_print != syscall_next) {

		printk("Task %d: %s()\n",

			stored_syscalls[syscall_next_print].pid,

			syscall_info_table[stored_syscalls[syscall_next_print].syscall_number].name);

			syscall_next_print++;

			syscall_next_print &= (N_STORED_SYSCALLS - 1);

	}

}



void evt_debug2(unsigned int ret)

{

	drain_syscalls();

	printk("Task %d: syscall returns %08x\n", current->pid, ret);

}



void evt_debug_ret_from_irq(struct pt_regs *regs)

{

	int pid;

	struct ring_node *rr;



	pid = current->pid;

	rr = event_ring + event_ptr;

	rr->evt = 0xffff;

	rr->ret_addr = 0;

	rr->event = 0;

	rr->tra = 0;

	rr->pid = pid;

	rr->pc = regs->pc;

	event_ptr = (event_ptr + 1) & 15;

}



void evt_debug_ret_from_exc(struct pt_regs *regs)

{

	int pid;

	struct ring_node *rr;



	pid = current->pid;

	rr = event_ring + event_ptr;

	rr->evt = 0xfffe;

	rr->ret_addr = 0;

	rr->event = 0;

	rr->tra = 0;

	rr->pid = pid;

	rr->pc = regs->pc;

	event_ptr = (event_ptr + 1) & 15;

}



#endif /* CONFIG_POOR_MANS_STRACE */



/* ======================================================================= */



void show_excp_regs(char *from, int trapnr, int signr, struct pt_regs *regs)

{