From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932208AbZBEBWn (ORCPT ); Wed, 4 Feb 2009 20:22:43 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753873AbZBEBWe (ORCPT ); Wed, 4 Feb 2009 20:22:34 -0500 Received: from mx2.redhat.com ([66.187.237.31]:36949 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752103AbZBEBWd (ORCPT ); Wed, 4 Feb 2009 20:22:33 -0500 Date: Wed, 4 Feb 2009 23:22:10 -0200 From: Arnaldo Carvalho de Melo To: Frederic Weisbecker Cc: Steven Rostedt , Ingo Molnar , Jens Axboe , Linux Kernel Mailing List Subject: Re: [PATCH tip 1/1] trace: assign defaults at register_ftrace_event Message-ID: <20090205012210.GQ3440@ghostprotocols.net> References: <20090204221639.GO3440@ghostprotocols.net> <20090204234150.GA11300@nowhere> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20090204234150.GA11300@nowhere> X-Url: http://oops.ghostprotocols.net:81/blog User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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? :-) - Arnaldo