From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762764Ab2KBNgl (ORCPT ); Fri, 2 Nov 2012 09:36:41 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:13989 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761200Ab2KBNfF (ORCPT ); Fri, 2 Nov 2012 09:35:05 -0400 X-Authority-Analysis: v=2.0 cv=YP4dOG6x c=1 sm=0 a=rXTBtCOcEpjy1lPqhTCpEQ==:17 a=mNMOxpOpBa8A:10 a=Ciwy3NGCPMMA:10 a=uio4Cusoyq4A:10 a=5SG0PmZfjMsA:10 a=bbbx4UPp9XUA:10 a=meVymXHHAAAA:8 a=2KByqrNPVRQA:10 a=20KFwNOVAAAA:8 a=2N7iOkv7plfqhN_ov1EA:9 a=QEXdDO2ut3YA:10 a=jEp0ucaQiEUA:10 a=Zh68SRI7RUMA:10 a=jeBq3FmKZ4MA:10 a=R5ATijz0JB5yeC7kUQoA:9 a=rXTBtCOcEpjy1lPqhTCpEQ==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.115.198 Message-Id: <20121102133501.643958787@goodmis.org> User-Agent: quilt/0.60-1 Date: Fri, 02 Nov 2012 09:33:12 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Frederic Weisbecker , Peter Zijlstra , Thomas Gleixner Subject: [PATCH 20/22] tracing: Remove deprecated tracing_enabled file References: <20121102133251.998500247@goodmis.org> Content-Disposition: inline; filename=0020-tracing-Remove-deprecated-tracing_enabled-file.patch Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="00GvhwF7k39YY" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --00GvhwF7k39YY Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable From: Steven Rostedt The tracing_enabled file was used as a quick way to stop tracers, and try to bring down overhead for things like the latency tracers (irqsoff, wakeup, etc). But it didn't work that well. The tracing_on file was created as a really fast way to stop recording into the ftrace ring buffer and can interact with the kernel. That is a tracing_off() call in the kernel can disable recording of events, and then from userspace one could echo 1 into the tracing_on file to continue it. The tracing_enabled function did too much to allow for this. The tracing_on has taken over as a way to start and stop tracing and the tracing_enabled file should not be used. But because of its existance, it still confuses people. Over a year ago the following commit was added: commit 6752ab4a9c30d5411b2dfdb251a3f1cb18aae487 Author: Steven Rostedt Date: Tue Feb 8 13:54:06 2011 -0500 tracing: Deprecate tracing_enabled for tracing_on This commit added a WARN_ON() if the tracing_enabled file's variable was changed. After this was added, only LatencyTop complained, and they soon fixed their tool as there was no reason that LatencyTop should touch this file as it was using the perf ring buffers which this file does not interact with. But since that time no one else has complained about this WARN_ON(). Thus it is safe to assume that this file is no longer needed. Time to get rid of it. Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 4b83a03..8eaa837 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4809,9 +4809,6 @@ static __init int tracer_init_debugfs(void) =20 d_tracer =3D tracing_init_dentry(); =20 - trace_create_file("tracing_enabled", 0644, d_tracer, - &global_trace, &rb_simple_fops); - trace_create_file("trace_options", 0644, d_tracer, NULL, &tracing_iter_fops); =20 --=20 1.7.10.4 --00GvhwF7k39YY Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQEcBAABAgAGBQJQk8wFAAoJEOdOSU1xswtMw4YH/jqPQbJfePQYAZt4QtHodUkJ DIaoRmHZ0KFDlWUIDe7FtNTqpVSUmeRyWEMZAE0dO4+ocoikNHBHLqCE50yHAgxZ N9lMtMKUvnvi13V1Ss94grzy4E9acwuSrXee7U6BG5wN90+7QbKPvAp0hN4LlCgZ HmnSPQ2F2MvGUELK2hrpHqMaiUW3BikSDhuTHMc05E7PbZpQ7TzyOx7F9Zp4uaAE h/fhXPxt5S7DFFqG/ooa1TjS4pMrkbCMQBfHzZSsAzzY9n/sEXE8STfAxE7kVx+4 piRieWGrHh/fMeEgfq5uAjDTCWBv8Ead0M2l2uf6Guz8xCYiMT0EvzigyLjMs2o= =ongz -----END PGP SIGNATURE----- --00GvhwF7k39YY--