From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 836A0C3A59E for ; Mon, 2 Sep 2019 14:39:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5CAC22087E for ; Mon, 2 Sep 2019 14:39:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731349AbfIBOji (ORCPT ); Mon, 2 Sep 2019 10:39:38 -0400 Received: from mx2.suse.de ([195.135.220.15]:39580 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727393AbfIBOji (ORCPT ); Mon, 2 Sep 2019 10:39:38 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id ED046B65E; Mon, 2 Sep 2019 14:39:35 +0000 (UTC) Date: Mon, 2 Sep 2019 16:39:35 +0200 From: Petr Mladek To: Sakari Ailus Cc: rafael@kernel.org, linux-kernel@vger.kernel.org, Rob Herring , Andy Shevchenko , Heikki Krogerus , devicetree@vger.kernel.org, linux-acpi@vger.kernel.org, Steven Rostedt , Arnaldo Carvalho de Melo , Tzvetomir Stoyanov , linux-trace-devel@vger.kernel.org, Jiri Olsa , Namhyung Kim Subject: Re: [PATCH v4 07/11] lib/vsprintf: Remove support for %pF and %pf in favour of %pS and %ps Message-ID: <20190902143935.xtd44jdvhjuc2wxe@pathway.suse.cz> References: <20190902083240.20367-1-sakari.ailus@linux.intel.com> <20190902083240.20367-8-sakari.ailus@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190902083240.20367-8-sakari.ailus@linux.intel.com> User-Agent: NeoMutt/20170912 (1.9.0) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 2019-09-02 11:32:36, Sakari Ailus wrote: > %pS and %ps are now the preferred conversion specifiers to print function > names. The functionality is equivalent; remove the old, deprecated %pF > and %pf support. Hmm, I see the following in master: $> git grep %pF tools/lib/traceevent/Documentation/libtraceevent-func_apis.txt:or events have "%pF" or "%pS" parameter in its format string. It is common to $> git grep %pf tools/lib/traceevent/event-parse.c: if (asprintf(&format, "%%pf: (NO FORMAT FOUND at %llx)\n", addr) < 0) tools/lib/traceevent/event-parse.c: if (asprintf(&format, "%s: %s", "%pf", printk->printk) < 0) I wonder how this is related to printk(). In each case, it seems that libtraceevent somehow implements the non-standard kernel %p mofifiers. It looks error-prone to keep another %pf user with the old semantic around. I am adding some tracing people into CC. Best Regards, Petr > Signed-off-by: Sakari Ailus > Reviewed-by: Andy Shevchenko > --- > Documentation/core-api/printk-formats.rst | 10 ---------- > lib/vsprintf.c | 8 ++------ > scripts/checkpatch.pl | 1 - > 3 files changed, 2 insertions(+), 17 deletions(-) > > diff --git a/Documentation/core-api/printk-formats.rst b/Documentation/core-api/printk-formats.rst > index c6224d039bcbe..922a29eb70e6c 100644 > --- a/Documentation/core-api/printk-formats.rst > +++ b/Documentation/core-api/printk-formats.rst > @@ -86,8 +86,6 @@ Symbols/Function Pointers > > %pS versatile_init+0x0/0x110 > %ps versatile_init > - %pF versatile_init+0x0/0x110 > - %pf versatile_init > %pSR versatile_init+0x9/0x110 > (with __builtin_extract_return_addr() translation) > %pB prev_fn_of_versatile_init+0x88/0x88 > @@ -97,14 +95,6 @@ The ``S`` and ``s`` specifiers are used for printing a pointer in symbolic > format. They result in the symbol name with (S) or without (s) > offsets. If KALLSYMS are disabled then the symbol address is printed instead. > > -Note, that the ``F`` and ``f`` specifiers are identical to ``S`` (``s``) > -and thus deprecated. We have ``F`` and ``f`` because on ia64, ppc64 and > -parisc64 function pointers are indirect and, in fact, are function > -descriptors, which require additional dereferencing before we can lookup > -the symbol. As of now, ``S`` and ``s`` perform dereferencing on those > -platforms (when needed), so ``F`` and ``f`` exist for compatibility > -reasons only. > - > The ``B`` specifier results in the symbol name with offsets and should be > used when printing stack backtraces. The specifier takes into > consideration the effect of compiler optimisations which may occur > diff --git a/lib/vsprintf.c b/lib/vsprintf.c > index b0967cf17137d..b00b57f9f911f 100644 > --- a/lib/vsprintf.c > +++ b/lib/vsprintf.c > @@ -909,7 +909,7 @@ char *symbol_string(char *buf, char *end, void *ptr, > #ifdef CONFIG_KALLSYMS > if (*fmt == 'B') > sprint_backtrace(sym, value); > - else if (*fmt != 'f' && *fmt != 's') > + else if (*fmt != 's') > sprint_symbol(sym, value); > else > sprint_symbol_no_offset(sym, value); > @@ -2007,9 +2007,7 @@ static char *kobject_string(char *buf, char *end, void *ptr, > * > * - 'S' For symbolic direct pointers (or function descriptors) with offset > * - 's' For symbolic direct pointers (or function descriptors) without offset > - * - 'F' Same as 'S' > - * - 'f' Same as 's' > - * - '[FfSs]R' as above with __builtin_extract_return_addr() translation > + * - '[Ss]R' as above with __builtin_extract_return_addr() translation > * - 'B' For backtraced symbolic direct pointers with offset > * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] > * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] > @@ -2112,8 +2110,6 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr, > struct printf_spec spec) > { > switch (*fmt) { > - case 'F': > - case 'f': > case 'S': > case 's': > ptr = dereference_symbol_descriptor(ptr); > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl > index 93a7edfe0f059..a60c241112cd4 100755 > --- a/scripts/checkpatch.pl > +++ b/scripts/checkpatch.pl > @@ -6012,7 +6012,6 @@ sub process { > my $ext_type = "Invalid"; > my $use = ""; > if ($bad_specifier =~ /p[Ff]/) { > - $ext_type = "Deprecated"; > $use = " - use %pS instead"; > $use =~ s/pS/ps/ if ($bad_specifier =~ /pf/); > } > -- > 2.20.1 >