From 67dce482018bc3103f02018d9682dcbb5154661f Mon Sep 17 00:00:00 2001 From: Wenyong Huang Date: Wed, 21 Aug 2024 12:55:34 +0800 Subject: [PATCH] Enable merged os_mmap for aot data sections and aot text (#3743) Enable merged os_mmap for aot data sections first, and try enabling merged os_mmap for them and aot text except on platform nuttx and esp-idf. This fixes the issue that aarch64 AOT module fails to load on android: https://github.com/bytecodealliance/wasm-micro-runtime/issues/2274 And also refine os_mmap related code. --- core/iwasm/aot/aot_loader.c | 243 ++++++++++++++++++++++++----------- core/iwasm/aot/aot_runtime.h | 7 + 2 files changed, 178 insertions(+), 72 deletions(-) diff --git a/core/iwasm/aot/aot_loader.c b/core/iwasm/aot/aot_loader.c index 645f68b1..b96079d3 100644 --- a/core/iwasm/aot/aot_loader.c +++ b/core/iwasm/aot/aot_loader.c @@ -294,6 +294,39 @@ loader_malloc(uint64 size, char *error_buf, uint32 error_buf_size) return mem; } +static void * +loader_mmap(uint32 size, bool prot_exec, char *error_buf, uint32 error_buf_size) +{ + int map_prot = + MMAP_PROT_READ | MMAP_PROT_WRITE | (prot_exec ? MMAP_PROT_EXEC : 0); + int map_flags; + void *mem; + +#if UINTPTR_MAX == UINT64_MAX + /* The mmapped AOT data and code in 64-bit targets had better be in + range 0 to 2G, or aot loader may fail to apply some relocations, + e.g., R_X86_64_32/R_X86_64_32S/R_X86_64_PC32/R_RISCV_32. + We try to mmap with MMAP_MAP_32BIT flag first, and if fails, mmap + again without the flag. */ + map_flags = MMAP_MAP_32BIT; + if ((mem = os_mmap(NULL, size, map_prot, map_flags, + os_get_invalid_handle()))) { + /* The mmapped memory must be in the first 2 Gigabytes of the + process address space */ + bh_assert((uintptr_t)mem < INT32_MAX); + return mem; + } +#endif + + map_flags = MMAP_MAP_NONE; + if (!(mem = os_mmap(NULL, size, map_prot, map_flags, + os_get_invalid_handle()))) { + set_error_buf(error_buf, error_buf_size, "allocate memory failed"); + return NULL; + } + return mem; +} + static char * load_string(uint8 **p_buf, const uint8 *buf_end, AOTModule *module, bool is_load_from_file_buf, @@ -2378,7 +2411,6 @@ destroy_object_data_sections(AOTObjectDataSection *data_sections, } } #endif - os_munmap(data_section->data, data_section->size); } wasm_runtime_free(data_sections); } @@ -2392,6 +2424,9 @@ load_object_data_sections(const uint8 **p_buf, const uint8 *buf_end, AOTObjectDataSection *data_sections; uint64 size; uint32 i; + uint64 total_size = 0; + uint32 page_size = os_getpagesize(); + uint8 *merged_sections = NULL; /* Allocate memory */ size = sizeof(AOTObjectDataSection) * (uint64)module->data_section_count; @@ -2400,41 +2435,40 @@ load_object_data_sections(const uint8 **p_buf, const uint8 *buf_end, return false; } - /* Create each data section */ + /* First iteration: read data from buf, and calculate total memory needed */ for (i = 0; i < module->data_section_count; i++) { - int map_prot = MMAP_PROT_READ | MMAP_PROT_WRITE; -#if defined(BUILD_TARGET_X86_64) || defined(BUILD_TARGET_AMD_64) \ - || defined(BUILD_TARGET_RISCV64_LP64D) \ - || defined(BUILD_TARGET_RISCV64_LP64) - /* aot code and data in x86_64 must be in range 0 to 2G due to - relocation for R_X86_64_32/32S/PC32 */ - int map_flags = MMAP_MAP_32BIT; -#else - int map_flags = MMAP_MAP_NONE; -#endif - read_string(buf, buf_end, data_sections[i].name); read_uint32(buf, buf_end, data_sections[i].size); - + CHECK_BUF(buf, buf_end, data_sections[i].size); + /* Temporary record data ptr for merge, will be replaced after the + merged_data_sections is mmapped */ + if (data_sections[i].size > 0) + data_sections[i].data = (uint8 *)buf; + buf += data_sections[i].size; + total_size += align_uint64((uint64)data_sections[i].size, page_size); + } + if (total_size > UINT32_MAX) { + set_error_buf(error_buf, error_buf_size, "data sections too large"); + return false; + } + if (total_size > 0) { /* Allocate memory for data */ - if (data_sections[i].size > 0 - && !(data_sections[i].data = - os_mmap(NULL, data_sections[i].size, map_prot, map_flags, - os_get_invalid_handle()))) { - set_error_buf(error_buf, error_buf_size, "allocate memory failed"); + merged_sections = module->merged_data_sections = + loader_mmap((uint32)total_size, false, error_buf, error_buf_size); + if (!merged_sections) { return false; } -#if defined(BUILD_TARGET_X86_64) || defined(BUILD_TARGET_AMD_64) -#if !defined(BH_PLATFORM_LINUX_SGX) && !defined(BH_PLATFORM_WINDOWS) \ - && !defined(BH_PLATFORM_DARWIN) - /* address must be in the first 2 Gigabytes of - the process address space */ - bh_assert((uintptr_t)data_sections[i].data < INT32_MAX); -#endif -#endif + module->merged_data_sections_size = (uint32)total_size; + } - read_byte_array(buf, buf_end, data_sections[i].data, - data_sections[i].size); + /* Second iteration: Create each data section */ + for (i = 0; i < module->data_section_count; i++) { + if (data_sections[i].size > 0) { + bh_memcpy_s(merged_sections, data_sections[i].size, + data_sections[i].data, data_sections[i].size); + data_sections[i].data = merged_sections; + merged_sections += align_uint(data_sections[i].size, page_size); + } } *p_buf = buf; @@ -2532,6 +2566,82 @@ fail: return false; } +#if !defined(BH_PLATFORM_NUTTX) && !defined(BH_PLATFORM_ESP_IDF) +static bool +try_merge_data_and_text(const uint8 **buf, const uint8 **buf_end, + AOTModule *module, char *error_buf, + uint32 error_buf_size) +{ + uint8 *old_buf = (uint8 *)*buf; + uint8 *old_end = (uint8 *)*buf_end; + size_t code_size = (size_t)(old_end - old_buf); + uint32 page_size = os_getpagesize(); + uint64 total_size = 0; + uint32 i; + uint8 *sections; + + if (code_size == 0) { + return true; + } + + /* calculate the total memory needed */ + total_size += align_uint64((uint64)code_size, page_size); + for (i = 0; i < module->data_section_count; ++i) { + total_size += + align_uint64((uint64)module->data_sections[i].size, page_size); + } + /* distance between .data and .text should not be greater than 4GB + for some targets (e.g. arm64 reloc need < 4G distance) */ + if (total_size > UINT32_MAX) { + return false; + } + /* code_size was checked and must be larger than 0 here */ + bh_assert(total_size > 0); + + sections = loader_mmap((uint32)total_size, false, NULL, 0); + if (!sections) { + /* merge failed but may be not critical for some targets */ + return false; + } + /* change the code part to be executable */ + if (os_mprotect(sections, code_size, + MMAP_PROT_READ | MMAP_PROT_WRITE | MMAP_PROT_EXEC) + != 0) { + os_munmap(sections, (uint32)total_size); + return false; + } + + module->merged_data_text_sections = sections; + module->merged_data_text_sections_size = (uint32)total_size; + + /* order not essential just as compiler does: .text section first */ + *buf = sections; + *buf_end = sections + code_size; + bh_memcpy_s(sections, code_size, old_buf, code_size); + os_munmap(old_buf, code_size); + sections += align_uint((uint32)code_size, page_size); + + /* then migrate .data sections */ + for (i = 0; i < module->data_section_count; ++i) { + AOTObjectDataSection *data_section = module->data_sections + i; + uint8 *old_data = data_section->data; + data_section->data = sections; + bh_memcpy_s(data_section->data, data_section->size, old_data, + data_section->size); + sections += align_uint(data_section->size, page_size); + } + /* free the original data sections */ + if (module->merged_data_sections) { + os_munmap(module->merged_data_sections, + module->merged_data_sections_size); + module->merged_data_sections = NULL; + module->merged_data_sections_size = 0; + } + + return true; +} +#endif /* ! defined(BH_PLATFORM_NUTTX) && !defined(BH_PLATFORM_ESP_IDF) */ + static bool load_text_section(const uint8 *buf, const uint8 *buf_end, AOTModule *module, char *error_buf, uint32 error_buf_size) @@ -3391,16 +3501,9 @@ load_relocation_section(const uint8 *buf, const uint8 *buf_end, + sizeof(uint64) * module->real_plt_count + sizeof(uint32) * module->float_plt_count; if (size > 0) { - map_prot = MMAP_PROT_READ | MMAP_PROT_WRITE | MMAP_PROT_EXEC; - /* aot code and data in x86_64 must be in range 0 to 2G due to - relocation for R_X86_64_32/32S/PC32 */ - map_flags = MMAP_MAP_32BIT; - if (size > UINT32_MAX - || !(module->extra_plt_data = - os_mmap(NULL, (uint32)size, map_prot, map_flags, - os_get_invalid_handle()))) { - set_error_buf(error_buf, error_buf_size, "mmap memory failed"); + || !(module->extra_plt_data = loader_mmap( + (uint32)size, true, error_buf, error_buf_size))) { goto fail; } module->extra_plt_data_size = (uint32)size; @@ -3512,19 +3615,12 @@ load_relocation_section(const uint8 *buf, const uint8 *buf_end, GOTItem *got_item = module->got_item_list; uint32 got_item_idx = 0; - map_prot = MMAP_PROT_READ | MMAP_PROT_WRITE; - /* aot code and data in x86_64 must be in range 0 to 2G due to - relocation for R_X86_64_32/32S/PC32 */ - map_flags = MMAP_MAP_32BIT; - /* Create the GOT for func_ptrs, note that it is different from the .got section of a dynamic object file */ size = (uint64)sizeof(void *) * got_item_count; if (size > UINT32_MAX - || !(module->got_func_ptrs = - os_mmap(NULL, (uint32)size, map_prot, map_flags, - os_get_invalid_handle()))) { - set_error_buf(error_buf, error_buf_size, "mmap memory failed"); + || !(module->got_func_ptrs = loader_mmap( + (uint32)size, false, error_buf, error_buf_size))) { goto fail; } @@ -3749,6 +3845,17 @@ load_from_sections(AOTModule *module, AOTSection *sections, return false; break; case AOT_SECTION_TYPE_TEXT: +#if !defined(BH_PLATFORM_NUTTX) && !defined(BH_PLATFORM_ESP_IDF) + /* try to merge .data and .text, with exceptions: + * 1. XIP mode + * 2. pre-mmapped module load from aot_load_from_sections() + * 3. nuttx & esp-idf: have separate region for MMAP_PROT_EXEC + */ + if (!module->is_indirect_mode && is_load_from_file_buf) + if (!try_merge_data_and_text(&buf, &buf_end, module, + error_buf, error_buf_size)) + LOG_WARNING("merge .data and .text sections failed"); +#endif /* ! defined(BH_PLATFORM_NUTTX) && !defined(BH_PLATFORM_ESP_IDF) */ if (!load_text_section(buf, buf_end, module, error_buf, error_buf_size)) return false; @@ -4065,37 +4172,16 @@ create_sections(AOTModule *module, const uint8 *buf, uint32 size, if (section_type == AOT_SECTION_TYPE_TEXT) { if ((section_size > 0) && !module->is_indirect_mode) { - int map_prot = - MMAP_PROT_READ | MMAP_PROT_WRITE | MMAP_PROT_EXEC; -#if defined(BUILD_TARGET_X86_64) || defined(BUILD_TARGET_AMD_64) \ - || defined(BUILD_TARGET_RISCV64_LP64D) \ - || defined(BUILD_TARGET_RISCV64_LP64) - /* aot code and data in x86_64 must be in range 0 to 2G due - to relocation for R_X86_64_32/32S/PC32 */ - int map_flags = MMAP_MAP_32BIT; -#else - int map_flags = MMAP_MAP_NONE; -#endif total_size = (uint64)section_size + aot_get_plt_table_size(); total_size = (total_size + 3) & ~((uint64)3); if (total_size >= UINT32_MAX || !(aot_text = - os_mmap(NULL, (uint32)total_size, map_prot, - map_flags, os_get_invalid_handle()))) { + loader_mmap((uint32)total_size, true, + error_buf, error_buf_size))) { wasm_runtime_free(section); - set_error_buf(error_buf, error_buf_size, - "mmap memory failed"); goto fail; } -#if defined(BUILD_TARGET_X86_64) || defined(BUILD_TARGET_AMD_64) -#if !defined(BH_PLATFORM_LINUX_SGX) && !defined(BH_PLATFORM_WINDOWS) \ - && !defined(BH_PLATFORM_DARWIN) - /* address must be in the first 2 Gigabytes of - the process address space */ - bh_assert((uintptr_t)aot_text < INT32_MAX); -#endif -#endif #if (WASM_MEM_DUAL_BUS_MIRROR != 0) mirrored_text = os_get_dbus_mirror(aot_text); @@ -4179,7 +4265,11 @@ load(const uint8 *buf, uint32 size, AOTModule *module, if (!ret) { /* If load_from_sections() fails, then aot text is destroyed in destroy_sections() */ - destroy_sections(section_list, module->is_indirect_mode ? false : true); + destroy_sections(section_list, + module->is_indirect_mode + || module->merged_data_text_sections + ? false + : true); /* aot_unload() won't destroy aot text again */ module->code = NULL; } @@ -4329,7 +4419,8 @@ aot_unload(AOTModule *module) } #endif - if (module->code && !module->is_indirect_mode) { + if (module->code && !module->is_indirect_mode + && !module->merged_data_text_sections) { /* The layout is: literal size + literal + code (with plt table) */ uint8 *mmap_addr = module->literal - sizeof(uint32); uint32 total_size = @@ -4364,6 +4455,14 @@ aot_unload(AOTModule *module) destroy_object_data_sections(module->data_sections, module->data_section_count); + if (module->merged_data_sections) + os_munmap(module->merged_data_sections, + module->merged_data_sections_size); + + if (module->merged_data_text_sections) + os_munmap(module->merged_data_text_sections, + module->merged_data_text_sections_size); + #if WASM_ENABLE_DEBUG_AOT != 0 jit_code_entry_destroy(module->elf_hdr); #endif diff --git a/core/iwasm/aot/aot_runtime.h b/core/iwasm/aot/aot_runtime.h index d109ceba..0eb64798 100644 --- a/core/iwasm/aot/aot_runtime.h +++ b/core/iwasm/aot/aot_runtime.h @@ -315,6 +315,13 @@ typedef struct AOTModule { /* Whether the underlying wasm binary buffer can be freed */ bool is_binary_freeable; + + /* `.data` sections merged into one mmaped to reduce the tlb cache miss */ + uint8 *merged_data_sections; + uint32 merged_data_sections_size; + /* `.data` and `.text` sections merged into one large mmaped section */ + uint8 *merged_data_text_sections; + uint32 merged_data_text_sections_size; } AOTModule; #define AOTMemoryInstance WASMMemoryInstance