Commit f4625ee0 authored by Guo Ren's avatar Guo Ren
Browse files

csky: Use in_syscall & forget_syscall instead of r11_sig 



We could use regs->sr 16-24 bits to detect syscall: VEC_TRAP0 and
r11_sig is no necessary for current implementation.

In this patch, we implement the in_syscall and forget_syscall which are
inspired from arm & nds32, but csky pt_regs has no syscall_num element
and we just set zero to regs->sr's vector-bits-field instead.

For ret_from_fork, current task was forked from parent which is in syscall
progress and its regs->sr has been already setted with VEC_TRAP0. See:
arch/csky/kernel/process.c: copy_thread()

Signed-off-by: default avatarGuo Ren <ren_guo@c-sky.com>
parent f335b10f

arch/csky/abiv1/inc/abi/regdef.h

+0 −2
Original line number Diff line number Diff line
@@ -5,8 +5,6 @@ 
#define __ASM_CSKY_REGDEF_H



#define syscallid	r1

#define r11_sig		r11



#define regs_syscallid(regs) regs->regs[9]



/*

arch/csky/abiv2/inc/abi/regdef.h

+0 −2
Original line number Diff line number Diff line
@@ -5,8 +5,6 @@ 
#define __ASM_CSKY_REGDEF_H



#define syscallid	r7

#define r11_sig		r11



#define regs_syscallid(regs) regs->regs[3]



/*

arch/csky/include/asm/ptrace.h

+12 −0
Original line number Diff line number Diff line
@@ -5,6 +5,8 @@ 
#define __ASM_CSKY_PTRACE_H



#include <uapi/asm/ptrace.h>

#include <asm/traps.h>

#include <linux/types.h>



#ifndef __ASSEMBLY__
@@ -20,6 +22,16 @@ 
#define instruction_pointer(regs) ((regs)->pc)

#define profile_pc(regs) instruction_pointer(regs)



static inline bool in_syscall(struct pt_regs const *regs)

{

	return ((regs->sr >> 16) & 0xff) == VEC_TRAP0;

}



static inline void forget_syscall(struct pt_regs *regs)

{

	regs->sr &= ~(0xff << 16);

}



static inline unsigned long regs_return_value(struct pt_regs *regs)

{

	return regs->a0;

arch/csky/kernel/entry.S

+1 −10
Original line number Diff line number Diff line
@@ -99,7 +99,6 @@ ENTRY(csky_\name) 
	mov     a0, sp

	movi    a1, \is_write

	jbsr    do_page_fault

	movi    r11_sig, 0             /* r11 = 0, Not a syscall. */

	jmpi    ret_from_exception

.endm
@@ -189,7 +188,6 @@ ENTRY(ret_from_fork) 
	bmaski	r10, THREAD_SHIFT

	andn	r9, r10

	ldw	r8, (r9, TINFO_FLAGS)

	movi	r11_sig, 1

	ANDI_R3	r8, (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT)

	cmpnei	r8, 0

	bf	3f
@@ -224,12 +222,8 @@ exit_work: 
	/* If thread_info->flag is empty, RESTORE_ALL */

	cmpnei	r8, 0

	bf	1b

	mov	a1, sp

	mov	a0, r8

	mov	a2, r11_sig		/* syscall? */

	btsti	r8, TIF_SIGPENDING	/* delivering a signal? */

	/* prevent further restarts(set r11 = 0) */

	clrt	r11_sig

	mov	a1, sp

	jbsr	do_notify_resume	/* do signals */

	br	resume_userspace
@@ -239,13 +233,11 @@ work_resched: 
	jmpi	schedule



ENTRY(sys_rt_sigreturn)

	movi	r11_sig, 0

	jmpi	do_rt_sigreturn



ENTRY(csky_trap)

	SAVE_ALL EPC_KEEP

	psrset	ee

	movi	r11_sig, 0             /* r11 = 0, Not a syscall. */

	mov	a0, sp                 /* Push Stack pointer arg */

	jbsr	trap_c                 /* Call C-level trap handler */

	jmpi	ret_from_exception
@@ -279,7 +271,6 @@ ENTRY(csky_get_tls) 
ENTRY(csky_irq)

	SAVE_ALL EPC_KEEP

	psrset	ee

	movi	r11_sig, 0		/* r11 = 0, Not a syscall. */



#ifdef CONFIG_PREEMPT

	mov	r9, sp			/* Get current stack  pointer */

arch/csky/kernel/signal.c

+9 −6
Original line number Diff line number Diff line
@@ -224,7 +224,7 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs) 
 * that the kernel can handle, and then we build all the user-level signal

 * handling stack-frames in one go after that.

 */

static void do_signal(struct pt_regs *regs, int syscall)

static void do_signal(struct pt_regs *regs)

{

	unsigned int retval = 0, continue_addr = 0, restart_addr = 0;

	struct ksignal ksig;
@@ -241,7 +241,9 @@ static void do_signal(struct pt_regs *regs, int syscall) 
	/*

	 * If we were from a system call, check for system call restarting...

	 */

	if (syscall) {

	if (in_syscall(regs)) {

		forget_syscall(regs);



		continue_addr = regs->pc;

#if defined(__CSKYABIV2__)

		restart_addr = continue_addr - 4;
@@ -249,7 +251,6 @@ static void do_signal(struct pt_regs *regs, int syscall) 
		restart_addr = continue_addr - 2;

#endif

		retval = regs->a0;



		/*

		 * Prepare for system call restart.  We do this here so that a

		 * debugger will see the already changed.
@@ -304,7 +305,9 @@ static void do_signal(struct pt_regs *regs, int syscall) 
	}



no_signal:

	if (syscall) {

	if (in_syscall(regs)) {

		forget_syscall(regs);



		/*

		 * Handle restarting a different system call.  As above,

		 * if a debugger has chosen to restart at a different PC,
@@ -333,10 +336,10 @@ no_signal: 
}



asmlinkage void

do_notify_resume(unsigned int thread_flags, struct pt_regs *regs, int syscall)

do_notify_resume(unsigned int thread_flags, struct pt_regs *regs)

{

	if (thread_flags & _TIF_SIGPENDING)

		do_signal(regs, syscall);

		do_signal(regs);



	if (thread_flags & _TIF_NOTIFY_RESUME) {

		clear_thread_flag(TIF_NOTIFY_RESUME);

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