2009/9/15, Peter Zijlstra <peterz@xxxxxxxxxxxxx>: > On Mon, 2009-09-14 at 20:41 +0200, Frederic Weisbecker wrote: >> On Mon, Sep 14, 2009 at 02:31:16PM -0400, Steven Rostedt wrote: >> > On Mon, 2009-09-14 at 20:23 +0200, Peter Zijlstra wrote: >> > > On Mon, 2009-09-14 at 14:17 -0400, Steven Rostedt wrote: >> > > > Frederic, how big can one of those events get. The ring buffer (and >> > > > TRACE_EVENT) allow up to almost a page size, which is very hefty for >> > > > the >> > > > stack. This code needs to either be rewritten or we need to set a >> > > > limit >> > > > to the size of a profile entry. >> > > >> > > Yeah, that needs to get a re-write.. I've complained about this when >> > > it >> > > went in. >> > >> > One answer is to create a per cpu buffer that is big enough to hold the >> > data needed. Then you can disable interrupts an use it without worry. >> > >> > If you need to also handle NMIs, then create a per_cpu NMI buffer too, >> > and use that if "in_nmi()" is true. >> > >> > -- Steve >> >> >> Looks like a nice idea. >> >> Peter, does that sound acceptable to you to disable interrupts during a >> profiled tracepoint event? > > It does anyway, a little further down the line, so sure. Ok I'll fix it soon using Steve's idea then. Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
