From mboxrd@z Thu Jan 1 00:00:00 1970 From: rostedt@goodmis.org (Steven Rostedt) Date: Wed, 17 Jun 2015 14:47:09 -0400 Subject: [lttng-dev] [RFC PATCH] sched: Fix sched_wakeup tracepoint In-Reply-To: References: <1433504509-17013-1-git-send-email-mathieu.desnoyers@efficios.com> <20150605120909.GG19282@twins.programming.kicks-ass.net> <479621151.4836.1433507522491.JavaMail.zimbra@efficios.com> <1433508695.1495.16.camel@twins> <600031664.4911.1433510581646.JavaMail.zimbra@efficios.com> <1433592142.1495.22.camel@twins> <1960877063.5553.1433672414640.JavaMail.zimbra@efficios.com> <20150608132735.0763ad27@gandalf.local.home> <20150609091336.GQ3644@twins.programming.kicks-ass.net> Message-ID: <20150617144709.5814a48d@gandalf.local.home> On Wed, 17 Jun 2015 11:23:00 -0700 Cong Wang wrote: > On Tue, Jun 9, 2015 at 2:13 AM, Peter Zijlstra wrote: > > > > So how about we introduce the 'waking' tracepoint and leave the existing > > wakeup one in place and preserve its woken semantics. > > > > Steven, can we do aliases? Where one tracepoint is known to userspace > > under multiple names? In that case we could rename the thing to woken > > and have an alias wakeup which we can phase out over time. > > > > The patch also takes away the success parameter to the tracepoint, but > > does not quite go as far as actually removing it from the tracepoint > > itself. > > > > We can do that in a follow up patch which we can quickly revert if it > > turns out people are actually still using that for something. > > +1 to this patch. How is it going? It's not a top priority. But it shouldn't be too hard to implement. This could be something I do after the 4.2 merge window closes. -- Steve > > Here at Twitter, we are analyzing scheduling latencies too, with our > own tool using existing tracepoints, it would be nice to have more > granularity on the scheduling latency. > > And, you probably want to change perf sched to respect this > new 'waking' event too. ;) > > Thanks.