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: Guo Ren <ren_guo@c-sky.com>
This commit is contained in:
Guo Ren 2019-03-30 23:44:34 +08:00
parent f335b10f3b
commit f4625ee0e4
5 changed files with 22 additions and 20 deletions

View File

@ -5,8 +5,6 @@
#define __ASM_CSKY_REGDEF_H
#define syscallid r1
#define r11_sig r11
#define regs_syscallid(regs) regs->regs[9]
/*

View File

@ -5,8 +5,6 @@
#define __ASM_CSKY_REGDEF_H
#define syscallid r7
#define r11_sig r11
#define regs_syscallid(regs) regs->regs[3]
/*

View File

@ -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;

View File

@ -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 */

View File

@ -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 @@ static void do_signal(struct pt_regs *regs, int syscall)
}
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);