On Fri, 30 Aug 2013 09:35:18 -0700 "H. Peter Anvin" <h...@zytor.com> wrote:
> On 08/30/2013 08:51 AM, Steven Rostedt wrote: > > > > It does when dynamic tracing is enabled. But this issue is with static > > tracing, there's no code modification, thus all functions call > > mcount/__fentry__ and we need to look at a variable to determine if we > > should trace or not. > > > > And of course global variables are a no-no without special handling in > pre-paging mode. Sigh. > > You *could* bail out of the calling address is < PAGE_OFFSET. > We could do that too, as static tracing already gives us high overhead, I'm not sure how much more overhead another check like this even matters. Who uses static tracing? I only use it to test that it still works ;-) -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
