On Sat, Jul 14, 2007 at 03:20:02PM -0400, Mathieu Desnoyers wrote: > * Christoph Hellwig ([EMAIL PROTECTED]) wrote: > > On Fri, Jul 13, 2007 at 09:21:34PM -0400, Mathieu Desnoyers wrote: > > > Remove the kprobes mutex from kprobes.h, since it does not belong there. > > > Also > > > remove all use of this mutex in the architecture specific code, replacing > > > it by > > > a proper mutex lock/unlock in the architecture agnostic code. > > > > This is not very nice for avr32/sparc64 which have a noop arch_remove_kprobe > > and now need to take a mutex to do nothing. Maybe you can find a nice > > way to avoid that? > > > > Except for this issue making kprobes_mutex static to kprobes.c sounds like > > a good improvement. > > > > Since only unregister_kprobe() calls arch_remove_kprobe(), and only > after having removed the struct kprobe from the kprobes list (while the > kprobes mutex is held), I wonder if there is any need to hold the > kprobes mutex at all when calling arch_remove_kprobe(). It turns out > that only get_insn_slot()/free_insn_slot() (which is in > kernel/kprobes.c, but called from arch specific code) seems to really > use protection of this mutex.
Right. > Would it make sense to protect the kprobe_insn_pages list with a > new kprobe_insn_mutex, nestable in the kprobe_mutex ? Do you think it is required after your change to make kprobe_mutex static? But yes, for architectures that don't need a arch_remove_kprobe, the situation is a bit odd... a mutex to do nothing. IIRC, that was the primary reason why we made the mutex visible outside of kernel/kprobes.c Ananth - 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/
