Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759625Ab2EIPdZ (ORCPT ); Wed, 9 May 2012 11:33:25 -0400 Received: from merlin.infradead.org ([205.233.59.134]:53380 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758008Ab2EIPdU convert rfc822-to-8bit (ORCPT ); Wed, 9 May 2012 11:33:20 -0400 Message-ID: <1336577562.2527.58.camel@twins> Subject: Re: [RFC][PATCH] printk: Add %pb to print bitmaps From: Peter Zijlstra To: Ingo Molnar Cc: Igor Mammedov , Jiang Liu , linux-kernel@vger.kernel.org, pjt@google.com, tglx@linutronix.de, seto.hidetoshi@jp.fujitsu.com, Andrew Morton , Linus Torvalds , Joe Perches Date: Wed, 09 May 2012 17:32:42 +0200 In-Reply-To: <20120509141528.GA3623@gmail.com> References: <4FAA452A.1070909@gmail.com> <4FAA588B.5010404@redhat.com> <1336564330.2527.23.camel@twins> <4FAA5BFB.40309@redhat.com> <1336566096.2527.30.camel@twins> <1336566644.2527.33.camel@twins> <1336570043.2527.38.camel@twins> <20120509133607.GA26124@gmail.com> <1336571049.2527.43.camel@twins> <1336571947.2527.47.camel@twins> <20120509141528.GA3623@gmail.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT X-Mailer: Evolution 3.2.2- Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3680 Lines: 114 On Wed, 2012-05-09 at 16:15 +0200, Ingo Molnar wrote: > > I guess I should use %.*pb and keep the field_width in case someone > > manages to actually make bitmap_scnlistprintf() conform to it. The > > precision is unused anyway. > > That's a cute trick, and it's intuitive as well. kernel/sched/core.c:5570:3: warning: precision used with ‘%p’ gnu_printf format [-Wformat] /me curses a bit.. anybody? The below compiles and works (with the above caveat) and has all the style muck people 'wanted'. --- lib/vsprintf.c | 46 ++++++++++++++++++++++++++++++++-------------- 1 file changed, 32 insertions(+), 14 deletions(-) diff --git a/lib/vsprintf.c b/lib/vsprintf.c index abbabec..6bd9a66 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -25,6 +25,9 @@ #include #include #include +#include +#include +#include #include #include /* for PAGE_SIZE */ @@ -857,6 +860,9 @@ int kptr_restrict __read_mostly; * correctness of the format string and va_list arguments. * - 'K' For a kernel pointer that should be hidden from unprivileged users * - 'NF' For a netdev_features_t + * - 'b' For a bitmap; %.*pb is required and the precision is used as bitmap length + * - 'bc' For a cpumask + * - 'bn' For a nodemask * * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 * function pointers are really function descriptors, which contain a @@ -902,24 +908,21 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr, * 6: 000102...0f */ switch (fmt[1]) { - case '6': - return ip6_addr_string(buf, end, ptr, spec, fmt); - case '4': - return ip4_addr_string(buf, end, ptr, spec, fmt); + case '6': return ip6_addr_string(buf, end, ptr, spec, fmt); + case '4': return ip4_addr_string(buf, end, ptr, spec, fmt); } break; case 'U': return uuid_string(buf, end, ptr, spec, fmt); - case 'V': - { - va_list va; - - va_copy(va, *((struct va_format *)ptr)->va); - buf += vsnprintf(buf, end > buf ? end - buf : 0, - ((struct va_format *)ptr)->fmt, va); - va_end(va); - return buf; - } + case 'V': { + va_list va; + + va_copy(va, *((struct va_format *)ptr)->va); + buf += vsnprintf(buf, end > buf ? end - buf : 0, + ((struct va_format *)ptr)->fmt, va); + va_end(va); + return buf; + } case 'K': /* * %pK cannot be used in IRQ context because its test @@ -941,6 +944,18 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr, return netdev_feature_string(buf, end, ptr, spec); } break; + case 'b': { + int bits; + + switch (fmt[1]) { + case 'c': bits = nr_cpumask_bits; break; + case 'n': bits = MAX_NUMNODES; break; + default: bits = spec.precision; break; + } + + return buf + bitmap_scnlistprintf(buf, end - buf, ptr, bits); + } + default: break; } spec.flags |= SMALL; if (spec.field_width == -1) { @@ -1175,6 +1190,9 @@ int format_decode(const char *fmt, struct printf_spec *spec) * %pI6c print an IPv6 address as specified by RFC 5952 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper * case. + * %.*pb print a bitmap list using the precision as bitmap length + * %pbc print a cpumask bitmap + * %pbn print a nodemask bitmap * %n is ignored * * The return value is the number of characters which would -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/