From mboxrd@z Thu Jan 1 00:00:00 1970 From: Masami Hiramatsu Subject: Re: [PATCH v7 09/16] tracing: Add hist trigger snapshot() action test case Date: Wed, 28 Nov 2018 11:15:58 +0900 Message-ID: <20181128111558.5869fa4be7104314e833a801@kernel.org> References: <20181126220332.215b461779d1d57f37b46e20@kernel.org> <1543359225.4223.5.camel@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: rostedt@goodmis.org, tglx@linutronix.de, namhyung@kernel.org, vedang.patel@intel.com, bigeasy@linutronix.de, joel@joelfernandes.org, mathieu.desnoyers@efficios.com, julia@ni.com, linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org To: Tom Zanussi Return-path: In-Reply-To: <1543359225.4223.5.camel@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-rt-users.vger.kernel.org Hi Tom, On Tue, 27 Nov 2018 16:53:45 -0600 Tom Zanussi wrote: > > > +ping $LOCALHOST -c 3 > > > +nice -n 1 ping $LOCALHOST -c 3 > > > + > > > +echo 0 > /sys/kernel/debug/tracing/events/sched/enable > > > > Shouldn't we stop tracing instead of disabling the event? > > > > This is just reversing the enable, so should be fine, but I can stop > tracing instead if you prefer. Oops, maybe we have to check the difference between event enabling and trace enabling. echo 0 > tracing_on will stop writing ring buffer, but event may continue to be called. Does this mean hist will be updated? (and I guess preferrable behavior is to stop hist too, isn't it?) Thank you, -- Masami Hiramatsu