From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762123AbZBEB4W (ORCPT ); Wed, 4 Feb 2009 20:56:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755800AbZBEB4L (ORCPT ); Wed, 4 Feb 2009 20:56:11 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:40587 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756169AbZBEB4J (ORCPT ); Wed, 4 Feb 2009 20:56:09 -0500 Date: Thu, 5 Feb 2009 02:55:47 +0100 From: Ingo Molnar To: Frederic Weisbecker Cc: Arnaldo Carvalho de Melo , Steven Rostedt , Jens Axboe , Linux Kernel Mailing List Subject: Re: [PATCH tip 1/1] trace: assign defaults at register_ftrace_event Message-ID: <20090205015547.GA19742@elte.hu> References: <20090204221639.GO3440@ghostprotocols.net> <20090204234150.GA11300@nowhere> <20090205012210.GQ3440@ghostprotocols.net> <20090205012430.GA12067@elte.hu> <20090205014133.GB11300@nowhere> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20090205014133.GB11300@nowhere> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean 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=3.2.3 -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 * Frederic Weisbecker wrote: > On Thu, Feb 05, 2009 at 02:24:30AM +0100, Ingo Molnar wrote: > > > > * Arnaldo Carvalho de Melo wrote: > > > > > Em Thu, Feb 05, 2009 at 12:41:51AM +0100, Frederic Weisbecker escreveu: > > > > On Wed, Feb 04, 2009 at 08:16:39PM -0200, Arnaldo Carvalho de Melo wrote: > > > > > Impact: simplification of tracers > > > > > > > > > > As all tracers are doing this we might as well do it in > > > > > register_ftrace_event and save one branch each time we call these > > > > > callbacks. > > > > > > > > > > Cc: Ingo Molnar > > > > > Cc: Frédéric Weisbecker > > > > > Cc: Jens Axboe > > > > > Signed-off-by: Arnaldo Carvalho de Melo > > > > > --- > > > > > block/blktrace.c | 2 -- > > > > > kernel/trace/trace.c | 13 +++++-------- > > > > > kernel/trace/trace_branch.c | 3 --- > > > > > kernel/trace/trace_output.c | 13 +++++++++++-- > > > > > 4 files changed, 16 insertions(+), 15 deletions(-) > > > > > > > > > > diff --git a/block/blktrace.c b/block/blktrace.c > > > > > index c7698d1..1ebd068 100644 > > > > > --- a/block/blktrace.c > > > > > +++ b/block/blktrace.c > > > > > @@ -1243,8 +1243,6 @@ static struct trace_event trace_blk_event = { > > > > > .type = TRACE_BLK, > > > > > .trace = blk_trace_event_print, > > > > > .latency_trace = blk_trace_event_print, > > > > > - .raw = trace_nop_print, > > > > > - .hex = trace_nop_print, > > > > > .binary = blk_trace_event_print_binary, > > > > > }; > > > > > > > > > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > > > > > index fd51cf0..a5e4c0a 100644 > > > > > --- a/kernel/trace/trace.c > > > > > +++ b/kernel/trace/trace.c > > > > > @@ -1412,7 +1412,7 @@ static enum print_line_t print_lat_fmt(struct trace_iterator *iter) > > > > > goto partial; > > > > > } > > > > > > > > > > - if (event && event->latency_trace) > > > > > + if (event) > > > > > return event->latency_trace(iter, sym_flags); > > > > > > > > > > if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) > > > > > @@ -1441,7 +1441,7 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter) > > > > > goto partial; > > > > > } > > > > > > > > > > - if (event && event->trace) > > > > > + if (event) > > > > > return event->trace(iter, sym_flags); > > > > > > > > > > if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) > > > > > @@ -1467,7 +1467,7 @@ static enum print_line_t print_raw_fmt(struct trace_iterator *iter) > > > > > } > > > > > > > > > > event = ftrace_find_event(entry->type); > > > > > - if (event && event->raw) > > > > > + if (event) > > > > > return event->raw(iter, 0); > > > > > > > > > > if (!trace_seq_printf(s, "%d ?\n", entry->type)) > > > > > @@ -1494,7 +1494,7 @@ static enum print_line_t print_hex_fmt(struct trace_iterator *iter) > > > > > } > > > > > > > > > > event = ftrace_find_event(entry->type); > > > > > - if (event && event->hex) { > > > > > + if (event) { > > > > > enum print_line_t ret = event->hex(iter, 0); > > > > > if (ret != TRACE_TYPE_HANDLED) > > > > > return ret; > > > > > @@ -1536,10 +1536,7 @@ static enum print_line_t print_bin_fmt(struct trace_iterator *iter) > > > > > } > > > > > > > > > > event = ftrace_find_event(entry->type); > > > > > - if (event && event->binary) > > > > > - return event->binary(iter, 0); > > > > > - > > > > > - return TRACE_TYPE_HANDLED; > > > > > + return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; > > > > > } > > > > > > > > > > static int trace_empty(struct trace_iterator *iter) > > > > > diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c > > > > > index 7ac72a4..297deb2 100644 > > > > > --- a/kernel/trace/trace_branch.c > > > > > +++ b/kernel/trace/trace_branch.c > > > > > @@ -182,9 +182,6 @@ static struct trace_event trace_branch_event = { > > > > > .type = TRACE_BRANCH, > > > > > .trace = trace_branch_print, > > > > > .latency_trace = trace_branch_print, > > > > > - .raw = trace_nop_print, > > > > > - .hex = trace_nop_print, > > > > > - .binary = trace_nop_print, > > > > > }; > > > > > > > > > > static struct tracer branch_trace __read_mostly = > > > > > diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c > > > > > index b7380ee..b6e99af 100644 > > > > > --- a/kernel/trace/trace_output.c > > > > > +++ b/kernel/trace/trace_output.c > > > > > @@ -435,6 +435,17 @@ int register_ftrace_event(struct trace_event *event) > > > > > if (ftrace_find_event(event->type)) > > > > > goto out; > > > > > > > > > > + if (event->trace == NULL) > > > > > + event->trace = trace_nop_print; > > > > > + if (event->latency_trace == NULL) > > > > > + event->latency_trace = trace_nop_print; > > > > > + if (event->raw == NULL) > > > > > + event->raw = trace_nop_print; > > > > > + if (event->hex == NULL) > > > > > + event->hex = trace_nop_print; > > > > > + if (event->binary == NULL) > > > > > + event->binary = trace_nop_print; > > > > > + > > > > > key = event->type & (EVENT_HASHSIZE - 1); > > > > > > > > > > hlist_add_head_rcu(&event->node, &event_hash[key]); > > > > > @@ -874,8 +885,6 @@ static struct trace_event trace_print_event = { > > > > > .trace = trace_print_print, > > > > > .latency_trace = trace_print_print, > > > > > .raw = trace_print_raw, > > > > > - .hex = trace_nop_print, > > > > > - .binary = trace_nop_print, > > > > > }; > > > > > > > > > > static struct trace_event *events[] __initdata = { > > > > > -- > > > > > 1.6.0.6 > > > > > > > > > > > > > > > > > Nice! This avoids one branch for each entry printed. > > > > > > Is that an Acked-by in response to that CC? :-) > > > > yes, i generally treat such replies as an implicit Acked-by and add them - > > already added Fredric's acks to two other commits of yours earlier today. An > > explicit Acked-by is even more helpful though :-) > > > > Ingo > > > Heh, I'm not a tracing/core/ftrace maintainer, so I wouldn't dare put my > Acked-by unless it touches a file I started :-) Concerning > tracing/core/ftrace/tracers, I review the patches that come if I have the > time to and tell what I think about it. But in my opinion, the Acked-by on > this area are more appropriate if they come from Steven :-) if you read a patch, in an area of code that you know well (which you do in this case), and if you find the patch it a step forward with no defects then feel free to post an Acked-by. You absolutely dont have to be the primary author of a file to do that. All such help makes maintenance easier and is much appreciated. Ingo