Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933596AbZJMHJ6 (ORCPT ); Tue, 13 Oct 2009 03:09:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933559AbZJMHJ5 (ORCPT ); Tue, 13 Oct 2009 03:09:57 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:36719 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933529AbZJMHJ4 (ORCPT ); Tue, 13 Oct 2009 03:09:56 -0400 Date: Tue, 13 Oct 2009 09:08:53 +0200 From: Ingo Molnar To: Steven Rostedt Cc: mingo@redhat.com, hpa@zytor.com, mathieu.desnoyers@polymtl.ca, anton@samba.org, linux-kernel@vger.kernel.org, peterz@infradead.org, zhaolei@cn.fujitsu.com, xiaoguangrong@cn.fujitsu.com, fweisbec@gmail.com, tglx@linutronix.de, kosaki.motohiro@jp.fujitsu.com, linux-tip-commits@vger.kernel.org Subject: Re: [tip:timers/tracing] hrtimer: Add tracepoint for hrtimers Message-ID: <20091013070853.GA13175@elte.hu> References: <4A7F8B2B.5020908@cn.fujitsu.com> <1255404309.7113.948.camel@gandalf.stny.rr.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1255404309.7113.948.camel@gandalf.stny.rr.com> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2226 Lines: 62 * Steven Rostedt wrote: > On Wed, 2009-09-02 at 12:18 +0000, tip-bot for Xiao Guangrong wrote: > > > +/** > > + * hrtimer_start - called when the hrtimer is started > > + * @timer: pointer to struct hrtimer > > + */ > > +TRACE_EVENT(hrtimer_start, > > + > > + TP_PROTO(struct hrtimer *timer), > > + > > + TP_ARGS(timer), > > + > > + TP_STRUCT__entry( > > + __field( void *, timer ) > > + __field( void *, function ) > > + __field( s64, expires ) > > + __field( s64, softexpires ) > > + ), > > + > > + TP_fast_assign( > > + __entry->timer = timer; > > + __entry->function = timer->function; > > + __entry->expires = hrtimer_get_expires(timer).tv64; > > + __entry->softexpires = hrtimer_get_softexpires(timer).tv64; > > + ), > > + > > + TP_printk("hrtimer %p, func %pf, expires %llu, softexpires %llu", > > + __entry->timer, __entry->function, > > + (unsigned long long)ktime_to_ns((ktime_t) { > > + .tv64 = __entry->expires }), > > + (unsigned long long)ktime_to_ns((ktime_t) { > > + .tv64 = __entry->softexpires })) > > +); > > + > > I was just fixing up the trace-cmd parser (which is also used for perf) > and came across this code. That TP_printk shows up in the format file > as: > > print fmt: "hrtimer %p, func %pf, expires %llu, softexpires %llu", REC->timer, REC->function, (unsigned long long)(((ktime_t) { .tv64 = REC->expires }).tv64), (unsigned long long)(((ktime_t) { .tv64 = REC->softexpires }).tv64) > > Now I'm trying to parse this with a tool so that we can have something > that can read the binary output, and be able to easily figure it out by > reading the format files. But trying to parse: > > (unsigned long long)(((ktime_t) { .tv64 = REC->expires }).tv64) > > Is not easy. It's basically implementing a C interpreter :-( Btw., what i suggested quite some time ago was that we should bind tracepoints by emitting C source code stubs, which tools can then build and link in, using gcc. Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/