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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 60B7FCA9EAF for ; Mon, 21 Oct 2019 16:35:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 36FD4205ED for ; Mon, 21 Oct 2019 16:35:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728711AbfJUQfD (ORCPT ); Mon, 21 Oct 2019 12:35:03 -0400 Received: from [217.140.110.172] ([217.140.110.172]:57554 "EHLO foss.arm.com" rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1727805AbfJUQfD (ORCPT ); Mon, 21 Oct 2019 12:35:03 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3C4C8105A; Mon, 21 Oct 2019 09:34:40 -0700 (PDT) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 04AA83F71F; Mon, 21 Oct 2019 09:34:37 -0700 (PDT) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: amit.kachhap@arm.com, ard.biesheuvel@linaro.org, catalin.marinas@arm.com, deller@gmx.de, duwe@suse.de, james.morse@arm.com, jeyu@kernel.org, jpoimboe@redhat.com, jthierry@redhat.com, mark.rutland@arm.com, mingo@redhat.com, peterz@infradead.org, rostedt@goodmis.org, svens@stackframe.org, takahiro.akashi@linaro.org, will@kernel.org Subject: [PATCH 2/8] module/ftrace: handle patchable-function-entry Date: Mon, 21 Oct 2019 17:34:20 +0100 Message-Id: <20191021163426.9408-3-mark.rutland@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20191021163426.9408-1-mark.rutland@arm.com> References: <20191021163426.9408-1-mark.rutland@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When using patchable-function-entry, the compiler will record the callsites into a section named "__patchable_function_entries" rather than "__mcount_loc". Let's abstract this difference behind a new FTRACE_CALLSITE_SECTION, so that architectures don't have to handle this explicitly (e.g. with custom module linker scripts). As parisc currently handles this explicitly, it is fixed up accordingly, with its custom linker script removed. Since FTRACE_CALLSITE_SECTION is only defined when DYNAMIC_FTRACE is selected, the parisc module loading code is updated to only use the definition in that case. When DYNAMIC_FTRACE is not selected, modules shouldn't have this section, so this removes some redundant work in that case. I built parisc generic-{32,64}bit_defconfig with DYNAMIC_FTRACE enabled, and verified that the section made it into the .ko files for modules. Signed-off-by: Mark Rutland Cc: Helge Deller Cc: Ingo Molnar Cc: Jessica Yu Cc: Steven Rostedt Cc: Sven Schnelle --- arch/parisc/Makefile | 1 - arch/parisc/kernel/module.c | 10 +++++++--- arch/parisc/kernel/module.lds | 7 ------- include/linux/ftrace.h | 5 +++++ kernel/module.c | 2 +- 5 files changed, 13 insertions(+), 12 deletions(-) delete mode 100644 arch/parisc/kernel/module.lds diff --git a/arch/parisc/Makefile b/arch/parisc/Makefile index 36b834f1c933..dca8f2de8cf5 100644 --- a/arch/parisc/Makefile +++ b/arch/parisc/Makefile @@ -60,7 +60,6 @@ KBUILD_CFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY=1 \ -DFTRACE_PATCHABLE_FUNCTION_SIZE=$(NOP_COUNT) CC_FLAGS_FTRACE := -fpatchable-function-entry=$(NOP_COUNT),$(shell echo $$(($(NOP_COUNT)-1))) -KBUILD_LDS_MODULE += $(srctree)/arch/parisc/kernel/module.lds endif OBJCOPY_FLAGS =-O binary -R .note -R .comment -S diff --git a/arch/parisc/kernel/module.c b/arch/parisc/kernel/module.c index ac5f34993b53..1c50093e2ebe 100644 --- a/arch/parisc/kernel/module.c +++ b/arch/parisc/kernel/module.c @@ -43,6 +43,7 @@ #include #include #include +#include #include #include #include @@ -862,7 +863,7 @@ int module_finalize(const Elf_Ehdr *hdr, const char *strtab = NULL; const Elf_Shdr *s; char *secstrings; - int err, symindex = -1; + int symindex = -1; Elf_Sym *newptr, *oldptr; Elf_Shdr *symhdr = NULL; #ifdef DEBUG @@ -946,11 +947,13 @@ int module_finalize(const Elf_Ehdr *hdr, /* patch .altinstructions */ apply_alternatives(aseg, aseg + s->sh_size, me->name); +#ifdef CONFIG_DYNAMIC_FTRACE /* For 32 bit kernels we're compiling modules with * -ffunction-sections so we must relocate the addresses in the - *__mcount_loc section. + * ftrace callsite section. */ - if (symindex != -1 && !strcmp(secname, "__mcount_loc")) { + if (symindex != -1 && !strcmp(secname, FTRACE_CALLSITE_SECTION)) { + int err; if (s->sh_type == SHT_REL) err = apply_relocate((Elf_Shdr *)sechdrs, strtab, symindex, @@ -962,6 +965,7 @@ int module_finalize(const Elf_Ehdr *hdr, if (err) return err; } +#endif } return 0; } diff --git a/arch/parisc/kernel/module.lds b/arch/parisc/kernel/module.lds deleted file mode 100644 index 1a9a92aca5c8..000000000000 --- a/arch/parisc/kernel/module.lds +++ /dev/null @@ -1,7 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ - -SECTIONS { - __mcount_loc : { - *(__patchable_function_entries) - } -} diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 8a8cb3c401b2..cea0746c8f4c 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -709,6 +709,11 @@ static inline unsigned long get_lock_parent_ip(void) #ifdef CONFIG_FTRACE_MCOUNT_RECORD extern void ftrace_init(void); +#ifdef CC_USING_PATCHABLE_FUNCTION_ENTRY +#define FTRACE_CALLSITE_SECTION "__patchable_function_entries" +#else +#define FTRACE_CALLSITE_SECTION "__mcount_loc" +#endif #else static inline void ftrace_init(void) { } #endif diff --git a/kernel/module.c b/kernel/module.c index ff2d7359a418..acf7962936c4 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3222,7 +3222,7 @@ static int find_module_sections(struct module *mod, struct load_info *info) #endif #ifdef CONFIG_FTRACE_MCOUNT_RECORD /* sechdrs[0].sh_size is always zero */ - mod->ftrace_callsites = section_objs(info, "__mcount_loc", + mod->ftrace_callsites = section_objs(info, FTRACE_CALLSITE_SECTION, sizeof(*mod->ftrace_callsites), &mod->num_ftrace_callsites); #endif -- 2.11.0