diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2012-11-05 13:00:27 -0500 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2012-11-29 00:01:23 -0500 |
| commit | 22062a96300dabfef93368a28c34bdf35c9b8308 (patch) | |
| tree | 6e04303c437911d21079a34ac0853137eeb91f8b | |
| parent | 4f4202fe5ae9a43e59303f20d700571f695d7b1b (diff) | |
new helper: signal_pt_regs()
Always equal to task_pt_regs(current); defined only when we are in
signal delivery. It may be different from current_pt_regs() - e.g.
architectures like m68k may have pt_regs location on exception
different from that on a syscall and signals (just as ptrace handling)
may happen on exceptions as well as on syscalls.
When they are equal, it's often better to have signal_pt_regs
defined (in asm/ptrace.h) as current_pt_regs - that tends to be
optimized better than default would be. However, optimisation is
the only reason why we might want an arch-specific definition;
if current_pt_regs() and task_pt_regs(current) have different
values, the latter one is right.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| -rw-r--r-- | arch/alpha/include/asm/ptrace.h | 1 | ||||
| -rw-r--r-- | arch/h8300/include/asm/ptrace.h | 1 | ||||
| -rw-r--r-- | include/linux/ptrace.h | 9 |
3 files changed, 11 insertions, 0 deletions
diff --git a/arch/alpha/include/asm/ptrace.h b/arch/alpha/include/asm/ptrace.h index b87755a19554..b4c5b2fbb647 100644 --- a/arch/alpha/include/asm/ptrace.h +++ b/arch/alpha/include/asm/ptrace.h @@ -78,6 +78,7 @@ struct switch_stack { #define current_pt_regs() \ ((struct pt_regs *) ((char *)current_thread_info() + 2*PAGE_SIZE) - 1) +#define signal_pt_regs current_pt_regs #define force_successful_syscall_return() (current_pt_regs()->r0 = 0) diff --git a/arch/h8300/include/asm/ptrace.h b/arch/h8300/include/asm/ptrace.h index 00502a61bf0a..7468589a128b 100644 --- a/arch/h8300/include/asm/ptrace.h +++ b/arch/h8300/include/asm/ptrace.h @@ -62,6 +62,7 @@ struct pt_regs { #define profile_pc(regs) instruction_pointer(regs) #define current_pt_regs() ((struct pt_regs *) \ (THREAD_SIZE + (unsigned long)current_thread_info()) - 1) +#define signal_pt_regs() ((struct pt_regs *)current->thread.esp0) #endif /* __KERNEL__ */ #endif /* __ASSEMBLY__ */ #endif /* _H8300_PTRACE_H */ diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h index 7aefbae2452e..b8e6dcec78ae 100644 --- a/include/linux/ptrace.h +++ b/include/linux/ptrace.h @@ -333,6 +333,15 @@ static inline void user_single_step_siginfo(struct task_struct *tsk, #define ptrace_signal_deliver(regs, cookie) do { } while (0) #endif +/* + * unlike current_pt_regs(), this one is equal to task_pt_regs(current) + * on *all* architectures; the only reason to have a per-arch definition + * is optimisation. + */ +#ifndef signal_pt_regs +#define signal_pt_regs() task_pt_regs(current) +#endif + extern int task_current_syscall(struct task_struct *target, long *callno, unsigned long args[6], unsigned int maxargs, unsigned long *sp, unsigned long *pc); |