From mboxrd@z Thu Jan 1 00:00:00 1970 From: Frederic Weisbecker Subject: Re: [PATCH v4 1/5] irq: add tracepoint to softirq_raise Date: Fri, 3 Sep 2010 17:29:13 +0200 Message-ID: <20100903152909.GA5352@nowhere> References: <4C72422C.5070102@jp.fujitsu.com> <4C724298.4050509@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, davem@davemloft.net, kaneshige.kenji@jp.fujitsu.com, izumi.taku@jp.fujitsu.com, kosaki.motohiro@jp.fujitsu.com, nhorman@tuxdriver.com, laijs@cn.fujitsu.com, scott.a.mcmillan@intel.com, rostedt@goodmis.org, eric.dumazet@gmail.com, mathieu.desnoyers@polymtl.ca To: Koki Sanagi Return-path: Content-Disposition: inline In-Reply-To: <4C724298.4050509@jp.fujitsu.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Mon, Aug 23, 2010 at 06:42:48PM +0900, Koki Sanagi wrote: > From: Lai Jiangshan > > Add a tracepoint for tracing when softirq action is raised. > > It and the existed tracepoints complete softirq's tracepoints: > softirq_raise, softirq_entry and softirq_exit. > > And when this tracepoint is used in combination with > the softirq_entry tracepoint we can determine > the softirq raise latency. > > Signed-off-by: Lai Jiangshan > Acked-by: Mathieu Desnoyers > Acked-by: Frederic Weisbecker > > [ factorize softirq events with DECLARE_EVENT_CLASS ] > Signed-off-by: Koki Sanagi > --- > include/linux/interrupt.h | 8 +++++++- > include/trace/events/irq.h | 26 ++++++++++++++++++++++++-- > 2 files changed, 31 insertions(+), 3 deletions(-) > > diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h > index a0384a4..d3e8e90 100644 > --- a/include/linux/interrupt.h > +++ b/include/linux/interrupt.h > @@ -18,6 +18,7 @@ > #include > #include > #include > +#include > > /* > * These correspond to the IORESOURCE_IRQ_* defines in > @@ -407,7 +408,12 @@ asmlinkage void do_softirq(void); > asmlinkage void __do_softirq(void); > extern void open_softirq(int nr, void (*action)(struct softirq_action *)); > extern void softirq_init(void); > -#define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL << (nr)); } while (0) > +static inline void __raise_softirq_irqoff(unsigned int nr) > +{ > + trace_softirq_raise((struct softirq_action *)&nr, NULL); > + or_softirq_pending(1UL << nr); > +} > + > extern void raise_softirq_irqoff(unsigned int nr); > extern void raise_softirq(unsigned int nr); > extern void wakeup_softirqd(void); > diff --git a/include/trace/events/irq.h b/include/trace/events/irq.h > index 0e4cfb6..3ddda02 100644 > --- a/include/trace/events/irq.h > +++ b/include/trace/events/irq.h > @@ -5,7 +5,9 @@ > #define _TRACE_IRQ_H > > #include > -#include > + > +struct irqaction; > +struct softirq_action; > > #define softirq_name(sirq) { sirq##_SOFTIRQ, #sirq } > #define show_softirq_name(val) \ > @@ -93,7 +95,10 @@ DECLARE_EVENT_CLASS(softirq, > ), > > TP_fast_assign( > - __entry->vec = (int)(h - vec); > + if (vec) > + __entry->vec = (int)(h - vec); > + else > + __entry->vec = *((int *)h); > ), It seems that this will break softirq_entry/exit tracepoints. __entry->vec will deref vec->action() for these two, which is not what we want. If you can't have the same tracepoint signature for the three, just split the new one in a seperate TRACE_EVENT(). Thanks.