* Frank Ch. Eigler ([EMAIL PROTECTED]) wrote: > Mathieu Desnoyers <[EMAIL PROTECTED]> writes: > > > This is an RFC for addition of a new thread flag, TIF_KERNEL_TRACE, to each > > architecture to activate system-wide system call tracing. > > [...] > > Instead of creating a new flag, could you overload TIF_SYSCALL_TRACE, > putting the marker into syscall_trace(), and letting !PT_TRACED cause > a skip over the ptrace notification logic? > > - FChE
I don't see any PT_TRACED flag in current kernel HEAD ? Hrm, let's see. If we share TIF_SYSCALL_TRACE with ptrace, we would then have to figure out how to get this working : - kernel tracing activated - ptracing some random processes - kernel tracing deactivated - stop ptracing those processes It means that we would have to keep some state information about the ptrace status of each process. This is currently kept by TIF_SYSCALL_TRACE, but since we would be overloading it, it would be lost when we deactivate kernel tracing. Adding a supplementary field to the thread_info structure is out of question here : we have to keep it as small as possible. So where do you propose to keep this information other than... another thread flag ? Mathieu -- Mathieu Desnoyers Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
