diff options
Diffstat (limited to 'include/asm-generic/vmlinux.lds.h')
| -rw-r--r-- | include/asm-generic/vmlinux.lds.h | 238 |
1 files changed, 127 insertions, 111 deletions
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 9c59409104f6..8ca130af301f 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -3,7 +3,7 @@ * linker scripts. * * A minimal linker scripts has following content: - * [This is a sample, architectures may have special requiriements] + * [This is a sample, architectures may have special requirements] * * OUTPUT_FORMAT(...) * OUTPUT_ARCH(...) @@ -50,6 +50,8 @@ * [__nosave_begin, __nosave_end] for the nosave data */ +#include <asm-generic/codetag.lds.h> + #ifndef LOAD_OFFSET #define LOAD_OFFSET 0 #endif @@ -85,32 +87,56 @@ #define ALIGN_FUNCTION() . = ALIGN(CONFIG_FUNCTION_ALIGNMENT) /* - * LD_DEAD_CODE_DATA_ELIMINATION option enables -fdata-sections, which - * generates .data.identifier sections, which need to be pulled in with - * .data. We don't want to pull in .data..other sections, which Linux - * has defined. Same for text and bss. + * Support -ffunction-sections by matching .text and .text.*, + * but exclude '.text..*', .text.startup[.*], and .text.exit[.*]. + * + * .text.startup and .text.startup.* are matched later by INIT_TEXT, and + * .text.exit and .text.exit.* are matched later by EXIT_TEXT, so they must be + * explicitly excluded here. * - * With LTO_CLANG, the linker also splits sections by default, so we need - * these macros to combine the sections during the final link. + * Other .text.* sections that are typically grouped separately, such as + * .text.unlikely or .text.hot, must be matched explicitly before using + * TEXT_MAIN. * - * RODATA_MAIN is not used because existing code already defines .rodata.x - * sections to be brought in with rodata. + * NOTE: builds *with* and *without* -ffunction-sections are both supported by + * this single macro. Even with -ffunction-sections, there may be some objects + * NOT compiled with the flag due to the use of a specific Makefile override + * like cflags-y or AUTOFDO_PROFILE_foo.o. So this single catchall rule is + * needed to support mixed object builds. + * + * One implication is that functions named startup(), exit(), split(), + * unlikely(), hot(), and unknown() are not allowed in the kernel due to the + * ambiguity of their section names with -ffunction-sections. For example, + * .text.startup could be __attribute__((constructor)) code in a *non* + * ffunction-sections object, which should be placed in .init.text; or it could + * be an actual function named startup() in an ffunction-sections object, which + * should be placed in .text. The build will detect and complain about any such + * ambiguously named functions. */ -#if defined(CONFIG_LD_DEAD_CODE_DATA_ELIMINATION) || defined(CONFIG_LTO_CLANG) -#define TEXT_MAIN .text .text.[0-9a-zA-Z_]* -#define DATA_MAIN .data .data.[0-9a-zA-Z_]* .data..L* .data..compoundliteral* .data.$__unnamed_* .data.$L* +#define TEXT_MAIN \ + .text \ + .text.[_0-9A-Za-df-rt-z]* \ + .text.s[_0-9A-Za-su-z]* .text.s .text.s.* \ + .text.st[_0-9A-Zb-z]* .text.st .text.st.* \ + .text.sta[_0-9A-Za-qs-z]* .text.sta .text.sta.* \ + .text.star[_0-9A-Za-su-z]* .text.star .text.star.* \ + .text.start[_0-9A-Za-tv-z]* .text.start .text.start.* \ + .text.startu[_0-9A-Za-oq-z]* .text.startu .text.startu.* \ + .text.startup[_0-9A-Za-z]* \ + .text.e[_0-9A-Za-wy-z]* .text.e .text.e.* \ + .text.ex[_0-9A-Za-hj-z]* .text.ex .text.ex.* \ + .text.exi[_0-9A-Za-su-z]* .text.exi .text.exi.* \ + .text.exit[_0-9A-Za-z]* + +/* + * Support -fdata-sections by matching .data, .data.*, and others, + * but exclude '.data..*'. + */ +#define DATA_MAIN .data .data.[0-9a-zA-Z_]* .data.rel.* .data..L* .data..compoundliteral* .data.$__unnamed_* .data.$L* #define SDATA_MAIN .sdata .sdata.[0-9a-zA-Z_]* #define RODATA_MAIN .rodata .rodata.[0-9a-zA-Z_]* .rodata..L* -#define BSS_MAIN .bss .bss.[0-9a-zA-Z_]* .bss..compoundliteral* +#define BSS_MAIN .bss .bss.[0-9a-zA-Z_]* .bss..L* .bss..compoundliteral* #define SBSS_MAIN .sbss .sbss.[0-9a-zA-Z_]* -#else -#define TEXT_MAIN .text -#define DATA_MAIN .data -#define SDATA_MAIN .sdata -#define RODATA_MAIN .rodata -#define BSS_MAIN .bss -#define SBSS_MAIN .sbss -#endif /* * GCC 4.5 and later have a 32 bytes section alignment for structures. @@ -131,6 +157,7 @@ *(__dl_sched_class) \ *(__rt_sched_class) \ *(__fair_sched_class) \ + *(__ext_sched_class) \ *(__idle_sched_class) \ __sched_class_lowest = .; @@ -138,21 +165,6 @@ * are handled as text/data or they can be discarded (which * often happens at runtime) */ -#ifdef CONFIG_HOTPLUG_CPU -#define CPU_KEEP(sec) *(.cpu##sec) -#define CPU_DISCARD(sec) -#else -#define CPU_KEEP(sec) -#define CPU_DISCARD(sec) *(.cpu##sec) -#endif - -#if defined(CONFIG_MEMORY_HOTPLUG) -#define MEM_KEEP(sec) *(.mem##sec) -#define MEM_DISCARD(sec) -#else -#define MEM_KEEP(sec) -#define MEM_DISCARD(sec) *(.mem##sec) -#endif #ifndef CONFIG_HAVE_DYNAMIC_FTRACE_NO_PATCHABLE #define KEEP_PATCHABLE KEEP(*(__patchable_function_entries)) @@ -162,7 +174,7 @@ #define PATCHABLE_DISCARDS *(__patchable_function_entries) #endif -#ifndef CONFIG_ARCH_SUPPORTS_CFI_CLANG +#ifndef CONFIG_ARCH_SUPPORTS_CFI /* * Simply points to ftrace_stub, but with the proper protocol. * Defined by the linker script in linux/vmlinux.lds.h @@ -172,7 +184,7 @@ #define FTRACE_STUB_HACK #endif -#ifdef CONFIG_FTRACE_MCOUNT_RECORD +#ifdef CONFIG_DYNAMIC_FTRACE /* * The ftrace call sites are logged to a section whose name depends on the * compiler option used. A given kernel image will only use one, AKA @@ -362,23 +374,24 @@ *(.data..decrypted) \ *(.ref.data) \ *(.data..shared_aligned) /* percpu related */ \ - MEM_KEEP(init.data*) \ - MEM_KEEP(exit.data*) \ - *(.data.unlikely) \ + *(.data..unlikely) \ __start_once = .; \ - *(.data.once) \ + *(.data..once) \ __end_once = .; \ + *(.data..do_once) \ STRUCT_ALIGN(); \ *(__tracepoints) \ /* implement dynamic printk debug */ \ . = ALIGN(8); \ BOUNDED_SECTION_BY(__dyndbg_classes, ___dyndbg_classes) \ BOUNDED_SECTION_BY(__dyndbg, ___dyndbg) \ + CODETAG_SECTIONS() \ LIKELY_PROFILE() \ BRANCH_PROFILE() \ TRACE_PRINTKS() \ BPF_RAW_TP() \ - TRACEPOINT_STR() + TRACEPOINT_STR() \ + KUNIT_TABLE() /* * Data section helpers @@ -390,6 +403,11 @@ . = ALIGN(PAGE_SIZE); \ __nosave_end = .; +#define CACHE_HOT_DATA(align) \ + . = ALIGN(align); \ + *(SORT_BY_ALIGNMENT(.data..hot.*)) \ + . = ALIGN(align); + #define PAGE_ALIGNED_DATA(page_align) \ . = ALIGN(page_align); \ *(.data..page_aligned) \ @@ -406,13 +424,12 @@ #define INIT_TASK_DATA(align) \ . = ALIGN(align); \ - __start_init_task = .; \ + __start_init_stack = .; \ init_thread_union = .; \ init_stack = .; \ - KEEP(*(.data..init_task)) \ KEEP(*(.data..init_thread_info)) \ - . = __start_init_task + THREAD_SIZE; \ - __end_init_task = .; + . = __start_init_stack + THREAD_SIZE; \ + __end_init_stack = .; #define JUMP_TABLE_DATA \ . = ALIGN(8); \ @@ -462,7 +479,7 @@ . = ALIGN((align)); \ .rodata : AT(ADDR(.rodata) - LOAD_OFFSET) { \ __start_rodata = .; \ - *(.rodata) *(.rodata.*) \ + *(.rodata) *(.rodata.*) *(.data.rel.ro*) \ SCHED_DATA \ RO_AFTER_INIT_DATA /* Read only after init */ \ . = ALIGN(8); \ @@ -527,8 +544,6 @@ /* __*init sections */ \ __init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) { \ *(.ref.rodata) \ - MEM_KEEP(init.rodata) \ - MEM_KEEP(exit.rodata) \ } \ \ /* Built-in module parameters. */ \ @@ -563,26 +578,43 @@ __cpuidle_text_end = .; \ __noinstr_text_end = .; +#define TEXT_SPLIT \ + __split_text_start = .; \ + *(.text.split .text.split.[0-9a-zA-Z_]*) \ + __split_text_end = .; + +#define TEXT_UNLIKELY \ + __unlikely_text_start = .; \ + *(.text.unlikely .text.unlikely.*) \ + __unlikely_text_end = .; + +#define TEXT_HOT \ + __hot_text_start = .; \ + *(.text.hot .text.hot.*) \ + __hot_text_end = .; + /* * .text section. Map to function alignment to avoid address changes * during second ld run in second ld pass when generating System.map * - * TEXT_MAIN here will match .text.fixup and .text.unlikely if dead - * code elimination is enabled, so these sections should be converted - * to use ".." first. + * TEXT_MAIN here will match symbols with a fixed pattern (for example, + * .text.hot or .text.unlikely). Match those before TEXT_MAIN to ensure + * they get grouped together. + * + * Also placing .text.hot section at the beginning of a page, this + * would help the TLB performance. */ #define TEXT_TEXT \ ALIGN_FUNCTION(); \ - *(.text.hot .text.hot.*) \ - *(TEXT_MAIN .text.fixup) \ - *(.text.unlikely .text.unlikely.*) \ + *(.text.asan.* .text.tsan.*) \ *(.text.unknown .text.unknown.*) \ + TEXT_SPLIT \ + TEXT_UNLIKELY \ + . = ALIGN(PAGE_SIZE); \ + TEXT_HOT \ + *(TEXT_MAIN .text.fixup) \ NOINSTR_TEXT \ - *(.ref.text) \ - *(.text.asan.* .text.tsan.*) \ - MEM_KEEP(init.text*) \ - MEM_KEEP(exit.text*) \ - + *(.ref.text) /* sched.text is aling to function alignment to secure we have same * address even at second ld pass when generating System.map */ @@ -652,10 +684,11 @@ */ #ifdef CONFIG_DEBUG_INFO_BTF #define BTF \ + . = ALIGN(PAGE_SIZE); \ .BTF : AT(ADDR(.BTF) - LOAD_OFFSET) { \ BOUNDED_SECTION_BY(.BTF, _BTF) \ } \ - . = ALIGN(4); \ + . = ALIGN(PAGE_SIZE); \ .BTF_ids : AT(ADDR(.BTF_ids) - LOAD_OFFSET) { \ *(.BTF_ids) \ } @@ -688,7 +721,6 @@ #define INIT_DATA \ KEEP(*(SORT(___kentry+*))) \ *(.init.data .init.data.*) \ - MEM_DISCARD(init.data*) \ KERNEL_CTORS() \ MCOUNT_REC() \ *(.init.rodata .init.rodata.*) \ @@ -696,7 +728,6 @@ TRACE_SYSCALLS() \ KPROBE_BLACKLIST() \ ERROR_INJECT_WHITELIST() \ - MEM_DISCARD(init.rodata) \ CLK_OF_TABLES() \ RESERVEDMEM_OF_TABLES() \ TIMER_OF_TABLES() \ @@ -710,24 +741,20 @@ EARLYCON_TABLE() \ LSM_TABLE() \ EARLY_LSM_TABLE() \ - KUNIT_TABLE() + KUNIT_INIT_TABLE() #define INIT_TEXT \ *(.init.text .init.text.*) \ - *(.text.startup) \ - MEM_DISCARD(init.text*) + *(.text.startup .text.startup.*) #define EXIT_DATA \ *(.exit.data .exit.data.*) \ *(.fini_array .fini_array.*) \ - *(.dtors .dtors.*) \ - MEM_DISCARD(exit.data*) \ - MEM_DISCARD(exit.rodata*) + *(.dtors .dtors.*) #define EXIT_TEXT \ *(.exit.text) \ - *(.text.exit) \ - MEM_DISCARD(exit.text) + *(.text.exit .text.exit.*) #define EXIT_CALL \ *(.exitcall.exit) @@ -821,6 +848,7 @@ /* Required sections not related to debugging. */ #define ELF_DETAILS \ + .modinfo : { *(.modinfo) . = ALIGN(8); } \ .comment 0 : { *(.comment) } \ .symtab 0 : { *(.symtab) } \ .strtab 0 : { *(.strtab) } \ @@ -934,11 +962,29 @@ #define CON_INITCALL \ BOUNDED_SECTION_POST_LABEL(.con_initcall.init, __con_initcall, _start, _end) +#define NAMED_SECTION(name) \ + . = ALIGN(8); \ + name : AT(ADDR(name) - LOAD_OFFSET) \ + { BOUNDED_SECTION_PRE_LABEL(name, name, __start_, __stop_) } + +#define RUNTIME_CONST(t,x) NAMED_SECTION(runtime_##t##_##x) + +#define RUNTIME_CONST_VARIABLES \ + RUNTIME_CONST(shift, d_hash_shift) \ + RUNTIME_CONST(ptr, dentry_hashtable) \ + RUNTIME_CONST(ptr, __dentry_cache) + /* Alignment must be consistent with (kunit_suite *) in include/kunit/test.h */ #define KUNIT_TABLE() \ . = ALIGN(8); \ BOUNDED_SECTION_POST_LABEL(.kunit_test_suites, __kunit_suites, _start, _end) +/* Alignment must be consistent with (kunit_suite *) in include/kunit/test.h */ +#define KUNIT_INIT_TABLE() \ + . = ALIGN(8); \ + BOUNDED_SECTION_POST_LABEL(.kunit_init_test_suites, \ + __kunit_init_suites, _start, _end) + #ifdef CONFIG_BLK_DEV_INITRD #define INIT_RAM_FS \ . = ALIGN(4); \ @@ -990,7 +1036,7 @@ * -fsanitize=thread produce unwanted sections (.eh_frame * and .init_array.*), but CONFIG_CONSTRUCTORS wants to * keep any .init_array.* sections. - * https://bugs.llvm.org/show_bug.cgi?id=46478 + * https://llvm.org/pr46478 */ #ifdef CONFIG_UNWIND_TABLES #define DISCARD_EH_FRAME @@ -1016,9 +1062,10 @@ *(.discard) \ *(.discard.*) \ *(.export_symbol) \ - *(.modinfo) \ + *(.no_trim_symbol) \ /* ld.bfd warns about .gnu.version* even when not emitted */ \ *(.gnu.version*) \ + *(__tracepoint_check) \ #define DISCARDS \ /DISCARD/ : { \ @@ -1039,10 +1086,13 @@ */ #define PERCPU_INPUT(cacheline) \ __per_cpu_start = .; \ - *(.data..percpu..first) \ . = ALIGN(PAGE_SIZE); \ *(.data..percpu..page_aligned) \ . = ALIGN(cacheline); \ + __per_cpu_hot_start = .; \ + *(SORT_BY_ALIGNMENT(.data..percpu..hot.*)) \ + __per_cpu_hot_end = .; \ + . = ALIGN(cacheline); \ *(.data..percpu..read_mostly) \ . = ALIGN(cacheline); \ *(.data..percpu) \ @@ -1051,52 +1101,17 @@ __per_cpu_end = .; /** - * PERCPU_VADDR - define output section for percpu area + * PERCPU_SECTION - define output section for percpu area * @cacheline: cacheline size - * @vaddr: explicit base address (optional) - * @phdr: destination PHDR (optional) * * Macro which expands to output section for percpu area. * * @cacheline is used to align subsections to avoid false cacheline * sharing between subsections for different purposes. - * - * If @vaddr is not blank, it specifies explicit base address and all - * percpu symbols will be offset from the given address. If blank, - * @vaddr always equals @laddr + LOAD_OFFSET. - * - * @phdr defines the output PHDR to use if not blank. Be warned that - * output PHDR is sticky. If @phdr is specified, the next output - * section in the linker script will go there too. @phdr should have - * a leading colon. - * - * Note that this macros defines __per_cpu_load as an absolute symbol. - * If there is no need to put the percpu section at a predetermined - * address, use PERCPU_SECTION. - */ -#define PERCPU_VADDR(cacheline, vaddr, phdr) \ - __per_cpu_load = .; \ - .data..percpu vaddr : AT(__per_cpu_load - LOAD_OFFSET) { \ - PERCPU_INPUT(cacheline) \ - } phdr \ - . = __per_cpu_load + SIZEOF(.data..percpu); - -/** - * PERCPU_SECTION - define output section for percpu area, simple version - * @cacheline: cacheline size - * - * Align to PAGE_SIZE and outputs output section for percpu area. This - * macro doesn't manipulate @vaddr or @phdr and __per_cpu_load and - * __per_cpu_start will be identical. - * - * This macro is equivalent to ALIGN(PAGE_SIZE); PERCPU_VADDR(@cacheline,,) - * except that __per_cpu_load is defined as a relative symbol against - * .data..percpu which is required for relocatable x86_32 configuration. */ #define PERCPU_SECTION(cacheline) \ . = ALIGN(PAGE_SIZE); \ .data..percpu : AT(ADDR(.data..percpu) - LOAD_OFFSET) { \ - __per_cpu_load = .; \ PERCPU_INPUT(cacheline) \ } @@ -1125,6 +1140,7 @@ INIT_TASK_DATA(inittask) \ NOSAVE_DATA \ PAGE_ALIGNED_DATA(pagealigned) \ + CACHE_HOT_DATA(cacheline) \ CACHELINE_ALIGNED_DATA(cacheline) \ READ_MOSTLY_DATA(cacheline) \ DATA_DATA \ |