From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756670AbZCFRDr (ORCPT ); Fri, 6 Mar 2009 12:03:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756089AbZCFRCs (ORCPT ); Fri, 6 Mar 2009 12:02:48 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:59467 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756393AbZCFRCp (ORCPT ); Fri, 6 Mar 2009 12:02:45 -0500 Date: Fri, 6 Mar 2009 18:02:22 +0100 From: Ingo Molnar To: Steven Rostedt Cc: Frederic Weisbecker , LKML , Andrew Morton , Lai Jiangshan , Linus Torvalds , Peter Zijlstra Subject: Re: [PATCH 4/5 v3] tracing/core: drop the old ftrace_printk implementation in favour of ftrace_bprintk Message-ID: <20090306170222.GA11285@elte.hu> References: <1236356510-8381-1-git-send-email-fweisbec@gmail.com> <1236356510-8381-5-git-send-email-fweisbec@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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 * Steven Rostedt wrote: > > > On Fri, 6 Mar 2009, Frederic Weisbecker wrote: > > > Impact: faster and lighter tracing > > > > Now that we have ftrace_bprintk() which is faster and consume lesser > > memory than ftrace_printk() and has the same purpose, we can now drop > > the old implementation in favour of the binary one from ftrace_bprintk(), > > which means we move all the implementation of ftrace_bprintk() to > > ftrace_printk(), so the Api doesn't change except that we must now use > > trace_seq_bprintk() to print the TRACE_PRINT entries. > > > > Some changes result of this: > > > > - Previously, ftrace_bprintk depended of a single tracer and couldn't > > work without. This tracer has been dropped and the whole implementation > > of ftrace_printk() (like the module formats management) is now integrated > > in the tracing core (comes with CONFIG_TRACING), though we keep the file > > trace_printk (previously trace_bprintk.c) where we can find the module > > management. Thus we don't overflow trace.c > > > > - changes some parts to use trace_seq_bprintk() to print TRACE_PRINT entries. > > > > - change a bit ftrace_printk/ftrace_vprintk macros to support non-builtin formats > > constants, and fix 'const' qualifiers warnings. But this is all transparent for > > developers. > > > > - etc... > > > > V2: > > > > - Rebase against last changes > > - Fix mispell on the changelog > > > > V3: > > > > - Rebase against last changes (moving ftrace_printk() to kernel.h) > > > > Signed-off-by: Frederic Weisbecker > > Very nice Frederic! > > For some reason I'm still missing patch 1. Perhaps it decided to take the > scenic route ;-) > > > diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h > > index 0f5077f..6140922 100644 > > --- a/kernel/trace/trace.h > > +++ b/kernel/trace/trace.h > > @@ -20,7 +20,6 @@ enum trace_type { > > TRACE_WAKE, > > TRACE_STACK, > > TRACE_PRINT, > > - TRACE_BPRINTK, > > TRACE_SPECIAL, > > TRACE_MMIO_RW, > > TRACE_MMIO_MAP, > > @@ -120,16 +119,10 @@ struct userstack_entry { > > */ > > struct print_entry { > > struct trace_entry ent; > > - unsigned long ip; > > + unsigned long ip; > > int depth; > > - char buf[]; > > -}; > > - > > > Note, this is going to break my recent patch that exports the > internal ftrace events. That's OK, I'll fix it after Ingo > pulls it in. > > Ingo, > > Would you prefer that I pull these patches in and then fix the > code, and let you pull it from me? i've put them into a separate branch forked off tip:tracing/ftrace: tip:tracing/printk. The two vsprintf patches are in tip:core/printk and merged into tracing/ftrace. You can thus apply your current enhancements without any interaction with me - and merge tracing/printk into the tip:tracing/ftrace branch on your own schedule, ok? Ingo