From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752179AbaCAHyc (ORCPT ); Sat, 1 Mar 2014 02:54:32 -0500 Received: from mx1.redhat.com ([209.132.183.28]:65370 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751468AbaCAHyb (ORCPT ); Sat, 1 Mar 2014 02:54:31 -0500 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <20140228211758.GB2517@katana> References: <20140228211758.GB2517@katana> <20140218203346.GG18768@katana> <20140109214954.25590.73057.stgit@warthog.procyon.org.uk> <10892.1393506444@warthog.procyon.org.uk> To: Wolfram Sang Cc: dhowells@redhat.com, wolfram@the-dreams.de, khali@linux-fr.org, linux-i2c@vger.kernel.org, Steven Rostedt , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] i2c: Add message transfer tracepoints for I2C Date: Sat, 01 Mar 2014 07:54:13 +0000 Message-ID: <24692.1393660453@warthog.procyon.org.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Wolfram Sang wrote: > > > And for the buffer: %*phN is difficult to read IMO. What about %*ph? Or > > > %*phD at least? > > > > My problem with that is that it increases the length of the output by 50% > > and there's a hard limit on how much output we may produce. > > Is it PAGE_SIZE? How is this handled when the buffer is so big that the > limit will be reached anyhow? Note that it is really uncommon to > transfer kilobytes in one go via i2c. Usually, big transfers are split > up into smaller fragments, say 128-256 byte. So, for readability, I'd > still favour %*ph. I was thinking that limited the size of the output field to 64 bytes. But reading vsprintf.c again, it appears it's actually the size of the binary blob that it's converting to hex that's limited to 64 bytes. I would prefer shorter lines - 128 bytes of hex still isn't entirely readable, even with separators interpolated, but I'll add this. David