From: Guo Ren <[email protected]> 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 <[email protected]> Cc: Arnd Bergmann <[email protected]> --- arch/csky/abiv1/inc/abi/regdef.h | 2 -- arch/csky/abiv2/inc/abi/regdef.h | 2 -- arch/csky/include/asm/ptrace.h | 12 ++++++++++++ arch/csky/kernel/entry.S | 11 +---------- arch/csky/kernel/signal.c | 15 +++++++++------ 5 files changed, 22 insertions(+), 20 deletions(-) diff --git a/arch/csky/abiv1/inc/abi/regdef.h b/arch/csky/abiv1/inc/abi/regdef.h index 8766892..9e7e692 100644 --- a/arch/csky/abiv1/inc/abi/regdef.h +++ b/arch/csky/abiv1/inc/abi/regdef.h @@ -5,8 +5,6 @@ #define __ASM_CSKY_REGDEF_H #define syscallid r1 -#define r11_sig r11 - #define regs_syscallid(regs) regs->regs[9] /* diff --git a/arch/csky/abiv2/inc/abi/regdef.h b/arch/csky/abiv2/inc/abi/regdef.h index c72abb7..652f5ce 100644 --- a/arch/csky/abiv2/inc/abi/regdef.h +++ b/arch/csky/abiv2/inc/abi/regdef.h @@ -5,8 +5,6 @@ #define __ASM_CSKY_REGDEF_H #define syscallid r7 -#define r11_sig r11 - #define regs_syscallid(regs) regs->regs[3] /* diff --git a/arch/csky/include/asm/ptrace.h b/arch/csky/include/asm/ptrace.h index 1e00578..d0aba7b 100644 --- a/arch/csky/include/asm/ptrace.h +++ b/arch/csky/include/asm/ptrace.h @@ -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; diff --git a/arch/csky/kernel/entry.S b/arch/csky/kernel/entry.S index c18859a..d40fbd5 100644 --- a/arch/csky/kernel/entry.S +++ b/arch/csky/kernel/entry.S @@ -32,7 +32,6 @@ RD_MEH a1 psrset ee, ie jbsr do_page_fault - movi r11_sig, 0 /* r11 = 0, Not a syscall. */ jmpi ret_from_exception .endm @@ -125,7 +124,6 @@ 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 @@ -160,12 +158,8 @@ 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 @@ -175,13 +169,11 @@ 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 @@ -215,7 +207,6 @@ 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 */ diff --git a/arch/csky/kernel/signal.c b/arch/csky/kernel/signal.c index 207a891..5a18940 100644 --- a/arch/csky/kernel/signal.c +++ b/arch/csky/kernel/signal.c @@ -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); -- 2.7.4
