task_current_syscall
This adds the new function task_current_syscall() on machines where the
asm/syscall.h interface is supported (CONFIG_HAVE_ARCH_TRACEHOOK). It's
exported for modules to use in the future. This function safely samples
the state of a blocked thread to collect what system call it is blocked
in, and the six system call argument registers.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
index ed69c03..fd31756 100644
--- a/include/linux/ptrace.h
+++ b/include/linux/ptrace.h
@@ -314,6 +314,10 @@
#define arch_ptrace_stop(code, info) do { } while (0)
#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);
+
#endif
#endif