From patchwork Thu Dec 22 02:38:06 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Chamberlain X-Patchwork-Id: 9484071 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 A2AC76016C for ; Thu, 22 Dec 2016 02:39:25 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 98632282E2 for ; Thu, 22 Dec 2016 02:39:25 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8C8F228410; Thu, 22 Dec 2016 02:39:25 +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 77B54283D4 for ; Thu, 22 Dec 2016 02:39:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764493AbcLVCjV (ORCPT ); Wed, 21 Dec 2016 21:39:21 -0500 Received: from mail.kernel.org ([198.145.29.136]:32800 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1764427AbcLVCjQ (ORCPT ); Wed, 21 Dec 2016 21:39:16 -0500 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 55F95203E1; Thu, 22 Dec 2016 02:39:13 +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 ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 16B1F203F4; Thu, 22 Dec 2016 02:39:09 +0000 (UTC) From: "Luis R. Rodriguez" To: hpa@zytor.com, acme@redhat.com, tglx@linutronix.de, mingo@redhat.com, jpoimboe@redhat.com, bp@alien8.de, npiggin@gmail.com, 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, dalias@libc.org, linux@arm.linux.org.uk Cc: x86@kernel.org, luto@amacapital.net, keescook@chromium.org, linux@roeck-us.net, 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, pebolle@tiscali.nl, fontana@sharpeleven.org, 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, jani.nikula@intel.com, mchehab@osg.samsung.com, markus.heiser@darmarit.de, jolsa@kernel.org, msalter@redhat.com, chris@zankel.net, jcmvbkbc@gmail.com, linux-xtensa@linux-xtensa.org, adrian.hunter@intel.com, dsahern@gmail.com, namhyung@kernel.org, wangnan0@huawei.com, dmitry.torokhov@gmail.com, joro@8bytes.org, paulus@samba.org, mpe@ellerman.id.au, James.Bottomley@HansenPartnership.com, "Luis R. Rodriguez" , Barry Song , Mike Frysinger , Michael Matz , Fengguang Wu Subject: [PATCH v5 10/14] dynamic_debug: port to use linker tables Date: Wed, 21 Dec 2016 18:38:06 -0800 Message-Id: <20161222023811.21246-11-mcgrof@kernel.org> X-Mailer: git-send-email 2.10.2 In-Reply-To: <20161222023811.21246-1-mcgrof@kernel.org> References: <1471642454-5679-1-git-send-email-mcgrof@kernel.org> <20161222023811.21246-1-mcgrof@kernel.org> X-Virus-Scanned: ClamAV using ClamSMTP Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This removes the custom vmlinux.lds.h hacks and uses the generalized solution for .data entries. There is much more potential for further fine tuning here in the future though. 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. We can work on this later to make this change easier to review. Tested dynamic debug with dyndbg query and debugfs control and it works as expected, for both built-in code and modules. v5: o Use ..tbl instead of .tbl as suggested by Nicholas Piggin. This is the typical way to avoid clash with compiler generated section. o Replace section macros with section names, use LINKTABLE_EMPTY(), LINKTABLE_START() v4: fix compilation on blackfin v3: added modular support v2: introduced this patch into the series Cc: Barry Song Cc: Mike Frysinger Cc: Steven Miao Cc: Michael Matz Cc: Guenter Roeck Cc: Fengguang Wu Signed-off-by: Luis R. Rodriguez --- include/asm-generic/vmlinux.lds.h | 4 ---- include/linux/dynamic_debug.h | 5 +++-- lib/dynamic_debug.c | 13 ++++++------- scripts/module-common.lds | 1 + 4 files changed, 10 insertions(+), 13 deletions(-) diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 887d844f0406..37b99537d5a9 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -216,10 +216,6 @@ *(.data.unlikely) \ STRUCT_ALIGN(); \ *(__tracepoints) \ - . = ALIGN(8); \ - VMLINUX_SYMBOL(__start___verbose) = .; \ - KEEP(*(__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..23da6bcf2f95 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 (LINKTABLE_EMPTY(__verbose)) { + pr_warn("dynamic debug linker table empty on CONFIG_DYNAMIC_DEBUG build\n"); return 1; } - iter = __start___verbose; + iter = LINKTABLE_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)(LINKTABLE_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 b/scripts/module-common.lds index db0e724556c5..25755d458f09 100644 --- a/scripts/module-common.lds +++ b/scripts/module-common.lds @@ -17,6 +17,7 @@ SECTIONS { __kcrctab_unused_gpl 0 : { *(SORT(___kcrctab_unused_gpl+*)) } __kcrctab_gpl_future 0 : { *(SORT(___kcrctab_gpl_future+*)) } __jump_table 0 : { *(SORT(.data..tbl.__jump_table.*)) } + __verbose 0 : { *(SORT(.data..tbl.__verbose.*)) } . = ALIGN(8); .init_array 0 : { *(SORT(.init_array.*)) *(.init_array) }