From patchwork Fri Jul 22 21:24:45 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Chamberlain X-Patchwork-Id: 9244307 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A161B60459 for ; Fri, 22 Jul 2016 21:25:45 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8F9A9280F4 for ; Fri, 22 Jul 2016 21:25:45 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 838F128111; Fri, 22 Jul 2016 21:25:45 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 47EF0280F4 for ; Fri, 22 Jul 2016 21:25:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754653AbcGVVZn (ORCPT ); Fri, 22 Jul 2016 17:25:43 -0400 Received: from mail.kernel.org ([198.145.29.136]:53384 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754515AbcGVVZe (ORCPT ); Fri, 22 Jul 2016 17:25:34 -0400 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id B42A02058E; Fri, 22 Jul 2016 21:25:32 +0000 (UTC) Received: from garbanzo.do-not-panic.com (c-73-15-241-2.hsd1.ca.comcast.net [73.15.241.2]) (using TLSv1.2 with cipher AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F23A7205DC; Fri, 22 Jul 2016 21:25:29 +0000 (UTC) From: "Luis R. Rodriguez" To: hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, linux@arm.linux.org.uk, mhiramat@kernel.org, masami.hiramatsu.pt@hitachi.com, jbaron@akamai.com, heiko.carstens@de.ibm.com, ananth@linux.vnet.ibm.com, anil.s.keshavamurthy@intel.com, davem@davemloft.net, realmz6@gmail.com Cc: x86@kernel.org, luto@amacapital.net, keescook@chromium.org, torvalds@linux-foundation.org, gregkh@linuxfoundation.org, rusty@rustcorp.com.au, gnomes@lxorguk.ukuu.org.uk, alan@linux.intel.com, dwmw2@infradead.org, arnd@arndb.de, ming.lei@canonical.com, linux-arch@vger.kernel.org, benh@kernel.crashing.org, ananth@in.ibm.com, pebolle@tiscali.nl, fontana@sharpeleven.org, ciaran.farrell@suse.com, christopher.denicolo@suse.com, david.vrabel@citrix.com, konrad.wilk@oracle.com, mcb30@ipxe.org, jgross@suse.com, andrew.cooper3@citrix.com, andriy.shevchenko@linux.intel.com, paul.gortmaker@windriver.com, xen-devel@lists.xensource.com, ak@linux.intel.com, pali.rohar@gmail.com, dvhart@infradead.org, platform-driver-x86@vger.kernel.org, mmarek@suse.com, linux@rasmusvillemoes.dk, jkosina@suse.cz, korea.drzix@gmail.com, linux-kbuild@vger.kernel.org, tony.luck@intel.com, akpm@linux-foundation.org, linux-ia64@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, catalin.marinas@arm.com, will.deacon@arm.com, rostedt@goodmis.org, jpoimboe@redhat.com, "Luis R. Rodriguez" Subject: [RFC v3 11/13] dynamic_debug: port to use linker tables Date: Fri, 22 Jul 2016 14:24:45 -0700 Message-Id: <1469222687-1600-12-git-send-email-mcgrof@kernel.org> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1469222687-1600-1-git-send-email-mcgrof@kernel.org> References: <1469222687-1600-1-git-send-email-mcgrof@kernel.org> X-Virus-Scanned: ClamAV using ClamSMTP Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This removes the custom vmlinux.lds.h hacks and uses the generalized solution for .data (SECTION_DATA) entries. This is much more potential for further fine tuning here though in the future. For instance, linker tables enable an extra postfix for order level annotations, this could easily be used as the KBUILD_MODNAME and with a bit of linker table changes we may be able to get a direct O(1) count of the entries for that KBUILD_MODNAME: it would just be a count on the number of entries for the given order level. This should help make dynamic_debug_init() cleaner and also reduce the amount of time it takes at boot time. Instead of iterating over each print until we have all for a KBUILD_MODNAME, we'd instead directly operate on each KBUILD_MODNAME directly. Tested dynamic debug with dyndbg query ana debugfs control and it works as expected, for both built-in code and modules. v3: added modular support v2: introduced this patch into the series Signed-off-by: Luis R. Rodriguez --- include/asm-generic/vmlinux.lds.h | 5 ----- include/linux/dynamic_debug.h | 5 +++-- lib/dynamic_debug.c | 13 ++++++------- scripts/module-common.lds.S | 1 + 4 files changed, 10 insertions(+), 14 deletions(-) diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index e186432a82e6..8048242b6a76 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -209,11 +209,6 @@ *(.data.unlikely) \ STRUCT_ALIGN(); \ *(__tracepoints) \ - /* implement dynamic printk debug */ \ - . = ALIGN(8); \ - VMLINUX_SYMBOL(__start___verbose) = .; \ - *(__verbose) \ - VMLINUX_SYMBOL(__stop___verbose) = .; \ LIKELY_PROFILE() \ BRANCH_PROFILE() \ TRACE_PRINTKS() \ diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index 546d68057e3b..a52618a77b09 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -4,6 +4,7 @@ #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) #include #endif +#include /* * An instance of this structure is created in a special @@ -50,6 +51,7 @@ int ddebug_add_module(struct _ddebug *tab, unsigned int n, const char *modname); #if defined(CONFIG_DYNAMIC_DEBUG) +DECLARE_LINKTABLE(struct _ddebug, __verbose); extern int ddebug_remove_module(const char *mod_name); extern __printf(2, 3) void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...); @@ -71,8 +73,7 @@ void __dynamic_netdev_dbg(struct _ddebug *descriptor, const char *fmt, ...); #define DEFINE_DYNAMIC_DEBUG_METADATA_KEY(name, fmt, key, init) \ - static struct _ddebug __aligned(8) \ - __attribute__((section("__verbose"))) name = { \ + static LINKTABLE(__verbose, SECTION_ORDER_ANY) name = { \ .modname = KBUILD_MODNAME, \ .function = __func__, \ .filename = __FILE__, \ diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index da796e2dc4f5..f0060c84c654 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -37,8 +37,7 @@ #include #include -extern struct _ddebug __start___verbose[]; -extern struct _ddebug __stop___verbose[]; +DEFINE_LINKTABLE(struct _ddebug, __verbose); struct ddebug_table { struct list_head link; @@ -978,14 +977,14 @@ static int __init dynamic_debug_init(void) int n = 0, entries = 0, modct = 0; int verbose_bytes = 0; - if (__start___verbose == __stop___verbose) { - pr_warn("_ddebug table is empty in a CONFIG_DYNAMIC_DEBUG build\n"); + if (LINUX_SECTION_EMPTY(__verbose)) { + pr_warn("dynamic debug linker table empty on CONFIG_DYNAMIC_DEBUG build\n"); return 1; } - iter = __start___verbose; + iter = LINUX_SECTION_START(__verbose); modname = iter->modname; iter_start = iter; - for (; iter < __stop___verbose; iter++) { + LINKTABLE_FOR_EACH(iter, __verbose) { entries++; verbose_bytes += strlen(iter->modname) + strlen(iter->function) + strlen(iter->filename) + strlen(iter->format); @@ -1008,7 +1007,7 @@ static int __init dynamic_debug_init(void) ddebug_init_success = 1; vpr_info("%d modules, %d entries and %d bytes in ddebug tables, %d bytes in (readonly) verbose section\n", modct, entries, (int)(modct * sizeof(struct ddebug_table)), - verbose_bytes + (int)(__stop___verbose - __start___verbose)); + verbose_bytes + (int)(LINUX_SECTION_SIZE(__verbose))); /* apply ddebug_query boot param, dont unload tables on err */ if (ddebug_setup_string[0] != '\0') { diff --git a/scripts/module-common.lds.S b/scripts/module-common.lds.S index d51140103ece..fec57aa5f4f1 100644 --- a/scripts/module-common.lds.S +++ b/scripts/module-common.lds.S @@ -21,6 +21,7 @@ SECTIONS { __kcrctab_unused_gpl 0 : { *(SORT(___kcrctab_unused_gpl+*)) } __kcrctab_gpl_future 0 : { *(SORT(___kcrctab_gpl_future+*)) } __jump_table 0 : { *(SORT(SECTION_TBL(SECTION_DATA, __jump_table, *))) } + __verbose 0 : { *(SORT(SECTION_TBL(SECTION_DATA, __verbose, *))) } . = ALIGN(8); .init_array 0 : { *(SORT(.init_array.*)) *(.init_array) }