From: Mark Rutland <mark.rutland@arm.com> 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 [thread overview] Message-ID: <20191021163426.9408-3-mark.rutland@arm.com> (raw) In-Reply-To: <20191021163426.9408-1-mark.rutland@arm.com> 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 <mark.rutland@arm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jessica Yu <jeyu@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sven Schnelle <svens@stackframe.org> --- 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 <linux/elf.h> #include <linux/vmalloc.h> #include <linux/fs.h> +#include <linux/ftrace.h> #include <linux/string.h> #include <linux/kernel.h> #include <linux/bug.h> @@ -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
WARNING: multiple messages have this Message-ID (diff)
From: Mark Rutland <mark.rutland@arm.com> To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: mark.rutland@arm.com, jthierry@redhat.com, will@kernel.org, ard.biesheuvel@linaro.org, peterz@infradead.org, catalin.marinas@arm.com, deller@gmx.de, jpoimboe@redhat.com, rostedt@goodmis.org, takahiro.akashi@linaro.org, mingo@redhat.com, james.morse@arm.com, jeyu@kernel.org, amit.kachhap@arm.com, svens@stackframe.org, duwe@suse.de Subject: [PATCH 2/8] module/ftrace: handle patchable-function-entry Date: Mon, 21 Oct 2019 17:34:20 +0100 [thread overview] Message-ID: <20191021163426.9408-3-mark.rutland@arm.com> (raw) In-Reply-To: <20191021163426.9408-1-mark.rutland@arm.com> 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 <mark.rutland@arm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jessica Yu <jeyu@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sven Schnelle <svens@stackframe.org> --- 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 <linux/elf.h> #include <linux/vmalloc.h> #include <linux/fs.h> +#include <linux/ftrace.h> #include <linux/string.h> #include <linux/kernel.h> #include <linux/bug.h> @@ -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 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-10-21 16:35 UTC|newest] Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-10-21 16:34 [PATCH 0/8] arm64: ftrace cleanup + FTRACE_WITH_REGS Mark Rutland 2019-10-21 16:34 ` Mark Rutland 2019-10-21 16:34 ` [PATCH 1/8] ftrace: add ftrace_init_nop() Mark Rutland 2019-10-21 16:34 ` Mark Rutland 2019-10-21 18:07 ` Steven Rostedt 2019-10-21 18:07 ` Steven Rostedt 2019-10-22 11:28 ` Mark Rutland 2019-10-22 11:28 ` Mark Rutland 2019-10-22 12:54 ` Steven Rostedt 2019-10-22 12:54 ` Steven Rostedt 2019-10-22 15:30 ` Mark Rutland 2019-10-22 15:30 ` Mark Rutland 2019-10-22 15:33 ` Mark Rutland 2019-10-22 15:33 ` Mark Rutland 2019-10-22 16:01 ` Steven Rostedt 2019-10-22 16:01 ` Steven Rostedt 2019-10-21 16:34 ` Mark Rutland [this message] 2019-10-21 16:34 ` [PATCH 2/8] module/ftrace: handle patchable-function-entry Mark Rutland 2019-10-21 16:34 ` [PATCH 3/8] arm64: module: rework special section handling Mark Rutland 2019-10-21 16:34 ` Mark Rutland 2019-10-21 16:34 ` [PATCH 4/8] arm64: module/ftrace: intialize PLT at load time Mark Rutland 2019-10-21 16:34 ` Mark Rutland 2019-10-21 16:34 ` [PATCH 5/8] arm64: insn: add encoder for MOV (register) Mark Rutland 2019-10-21 16:34 ` Mark Rutland 2019-10-21 16:34 ` [PATCH 6/8] arm64: asm-offsets: add S_FP Mark Rutland 2019-10-21 16:34 ` Mark Rutland 2019-10-21 16:34 ` [PATCH 7/8] arm64: implement ftrace with regs Mark Rutland 2019-10-21 16:34 ` Mark Rutland 2019-10-21 16:34 ` [PATCH 8/8] arm64: ftrace: minimize ifdeffery Mark Rutland 2019-10-21 16:34 ` Mark Rutland 2019-10-24 16:32 ` [PATCH 0/8] arm64: ftrace cleanup + FTRACE_WITH_REGS Ard Biesheuvel 2019-10-24 16:32 ` Ard Biesheuvel
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