On Thu, 29 Aug 2013, Steven Rostedt wrote: > On Thu, Aug 29, 2013 at 04:57:43PM +0000, Christoph Lameter wrote: > > > > We could add a ____this_cpu variant that would be used in the cases we do > > not want preemption checks? There should not be too many but it will > > mean a whole lot of new definitions in percpu.h. > > Let's get away from underscores as they are meaningless. > > A this_cpu_atomic() or other descriptive name would be much more > appropriate.
Its not really an atomic operation in the classic sense. this_cpu_no_preempt_check_read ? The problem that I have is also that a kernel with preemption is not something that see anywhere these days. Looks more like an academic exercise? Does this really matter? All the distro I see use PREEMPT_VOLUNTARY. Performance degradation is significant if massive amounts of checks and preempt disable/enable points are added to the kernel. Do we agree that it is necessary and useful to add another variant of this_cpu ops for this? The concern of having too many variants is no longer there? Adding another variant is not that difficult just code intensive. -- 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/
