From a8dde0a2114f87bcdc19946aeab26788f5eae1b7 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Tue, 27 Feb 2018 12:22:58 -0800 Subject: [PATCH] ld: Limit cache size and add --max-cache-size=SIZE When link_info.keep_memory is true, linker caches the relocation information and symbol tables of input files in memory. When there are many input files with many relocations, we may run out of memory. Add --max-cache-size=SIZE to set the maximum cache size. bfd/ PR ld/18028 * bfd.c (bfd): Add alloc_size. * elf-bfd.h (_bfd_elf_link_info_read_relocs): New. * elf32-i386.c (elf_i386_check_relocs): Use _bfd_link_keep_memory. Update cache_size. * elf64-x86-64.c (elf_x86_64_check_relocs): Likewise. * elflink.c (_bfd_elf_link_read_relocs): Renamed to ... (_bfd_elf_link_info_read_relocs): This. Update cache_size. (_bfd_elf_link_read_relocs): New. (_bfd_elf_link_check_relocs): Call _bfd_elf_link_info_read_relocs instead of _bfd_elf_link_read_relocs. (elf_link_add_object_symbols): Likewise. (elf_link_input_bfd): Likewise. (init_reloc_cookie_rels): Likewise. (init_reloc_cookie): Update cache_size. Call _bfd_elf_link_info_read_relocs instead of _bfd_elf_link_read_relocs. (link_info_ok): New. (elf_gc_smash_unused_vtentry_relocs): Updated. Call _bfd_elf_link_info_read_relocs instead of _bfd_elf_link_read_relocs. (bfd_elf_gc_sections): Use link_info_ok. Pass &link_info_ok to elf_gc_smash_unused_vtentry_relocs. * libbfd-in.h (_bfd_link_keep_memory): New. * linker.c (_bfd_link_keep_memory): New. * opncls.c (bfd_alloc): Update alloc_size. * bfd-in2.h: Regenerated. * libbfd.h: Likewise. include/ PR ld/18028 * bfdlink.h (bfd_link_info): Add cache_size and max_cache_size. ld/ PR ld/18028 * NEWS: Mention --max-cache-size=SIZE. * ld.texi: Document --max-cache-size=SIZE. * ldlex.h (option_values): Add OPTION_MAX_CACHE_SIZE. * ldmain.c: (main): Set link_info.max_cache_size to -1. * lexsup.c (ld_options): Add --max-cache-size=SIZE. (parse_args): Support OPTION_MAX_CACHE_SIZE. * testsuite/ld-bootstrap/bootstrap.exp: Add test for --max-cache-size=-1. --- bfd/bfd-in2.h | 3 + bfd/bfd.c | 3 + bfd/elf-bfd.h | 3 + bfd/elf32-i386.c | 3 +- bfd/elf64-x86-64.c | 3 +- bfd/elflink.c | 90 ++++++++++++++++++------- bfd/libbfd-in.h | 3 + bfd/libbfd.h | 3 + bfd/linker.c | 35 ++++++++++ bfd/opncls.c | 2 + include/bfdlink.h | 7 ++ ld/NEWS | 3 + ld/ld.texi | 6 ++ ld/ldlex.h | 1 + ld/ldmain.c | 1 + ld/lexsup.c | 15 +++++ ld/testsuite/ld-bootstrap/bootstrap.exp | 3 +- 17 files changed, 158 insertions(+), 26 deletions(-) diff --git a/bfd/bfd-in2.h b/bfd/bfd-in2.h index 9a698316980..43d4ff0b925 100644 --- a/bfd/bfd-in2.h +++ b/bfd/bfd-in2.h @@ -6717,6 +6717,9 @@ struct bfd be used only for archive elements. */ int archive_pass; + /* The total size of memory from bfd_alloc. */ + bfd_size_type alloc_size; + /* Stuff only useful for object files: The start address. */ bfd_vma start_address; diff --git a/bfd/bfd.c b/bfd/bfd.c index 0952aaea19c..eb555ad5df2 100644 --- a/bfd/bfd.c +++ b/bfd/bfd.c @@ -286,6 +286,9 @@ CODE_FRAGMENT . be used only for archive elements. *} . int archive_pass; . +. {* The total size of memory from bfd_alloc. *} +. bfd_size_type alloc_size; +. . {* Stuff only useful for object files: . The start address. *} . bfd_vma start_address; diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h index 8f985ab8917..65c08ca9d4a 100644 --- a/bfd/elf-bfd.h +++ b/bfd/elf-bfd.h @@ -2482,6 +2482,9 @@ extern char *_bfd_elfcore_strndup extern Elf_Internal_Rela *_bfd_elf_link_read_relocs (bfd *, asection *, void *, Elf_Internal_Rela *, bool); +extern Elf_Internal_Rela *_bfd_elf_link_info_read_relocs + (bfd *, struct bfd_link_info *, asection *, void *, Elf_Internal_Rela *, + bool); extern bool _bfd_elf_link_output_relocs (bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *, diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c index cf7cd076b17..1898ba3e33a 100644 --- a/bfd/elf32-i386.c +++ b/bfd/elf32-i386.c @@ -1915,13 +1915,14 @@ elf_i386_check_relocs (bfd *abfd, if (elf_section_data (sec)->this_hdr.contents != contents) { - if (!converted && !info->keep_memory) + if (!converted && !_bfd_link_keep_memory (info)) free (contents); else { /* Cache the section contents for elf_link_input_bfd if any load is converted or --no-keep-memory isn't used. */ elf_section_data (sec)->this_hdr.contents = contents; + info->cache_size += sec->size; } } diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c index 98fb88113c0..4c55c5999c3 100644 --- a/bfd/elf64-x86-64.c +++ b/bfd/elf64-x86-64.c @@ -2365,13 +2365,14 @@ elf_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info, if (elf_section_data (sec)->this_hdr.contents != contents) { - if (!converted && !info->keep_memory) + if (!converted && !_bfd_link_keep_memory (info)) free (contents); else { /* Cache the section contents for elf_link_input_bfd if any load is converted or --no-keep-memory isn't used. */ elf_section_data (sec)->this_hdr.contents = contents; + info->cache_size += sec->size; } } diff --git a/bfd/elflink.c b/bfd/elflink.c index 9a05208253c..003c9546b03 100644 --- a/bfd/elflink.c +++ b/bfd/elflink.c @@ -2619,14 +2619,16 @@ elf_link_read_relocs_from_section (bfd *abfd, according to the KEEP_MEMORY argument. If O has two relocation sections (both REL and RELA relocations), then the REL_HDR relocations will appear first in INTERNAL_RELOCS, followed by the - RELA_HDR relocations. */ + RELA_HDR relocations. If INFO isn't NULL and KEEP_MEMORY is true, + update cache_size. */ Elf_Internal_Rela * -_bfd_elf_link_read_relocs (bfd *abfd, - asection *o, - void *external_relocs, - Elf_Internal_Rela *internal_relocs, - bool keep_memory) +_bfd_elf_link_info_read_relocs (bfd *abfd, + struct bfd_link_info *info, + asection *o, + void *external_relocs, + Elf_Internal_Rela *internal_relocs, + bool keep_memory) { void *alloc1 = NULL; Elf_Internal_Rela *alloc2 = NULL; @@ -2646,7 +2648,11 @@ _bfd_elf_link_read_relocs (bfd *abfd, size = (bfd_size_type) o->reloc_count * sizeof (Elf_Internal_Rela); if (keep_memory) - internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_alloc (abfd, size); + { + internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_alloc (abfd, size); + if (info) + info->cache_size += size; + } else internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size); if (internal_relocs == NULL) @@ -2710,6 +2716,22 @@ _bfd_elf_link_read_relocs (bfd *abfd, return NULL; } +/* This is similar to _bfd_elf_link_info_read_relocs, except for that + NULL is passed to _bfd_elf_link_info_read_relocs for pointer to + struct bfd_link_info. */ + +Elf_Internal_Rela * +_bfd_elf_link_read_relocs (bfd *abfd, + asection *o, + void *external_relocs, + Elf_Internal_Rela *internal_relocs, + bool keep_memory) +{ + return _bfd_elf_link_info_read_relocs (abfd, NULL, o, external_relocs, + internal_relocs, keep_memory); + +} + /* Compute the size of, and allocate space for, REL_HDR which is the section header for a section containing relocations for O. */ @@ -4026,8 +4048,10 @@ _bfd_elf_link_check_relocs (bfd *abfd, struct bfd_link_info *info) || bfd_is_abs_section (o->output_section)) continue; - internal_relocs = _bfd_elf_link_read_relocs (abfd, o, NULL, NULL, - info->keep_memory); + internal_relocs = _bfd_elf_link_info_read_relocs (abfd, info, + o, NULL, + NULL, + _bfd_link_keep_memory (info)); if (internal_relocs == NULL) return false; @@ -5356,9 +5380,10 @@ elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info) && (s->flags & SEC_DEBUGGING) != 0)) continue; - internal_relocs = _bfd_elf_link_read_relocs (abfd, s, NULL, - NULL, - info->keep_memory); + internal_relocs = _bfd_elf_link_info_read_relocs (abfd, info, + s, NULL, + NULL, + _bfd_link_keep_memory (info)); if (internal_relocs == NULL) goto error_free_vers; @@ -11186,8 +11211,10 @@ elf_link_input_bfd (struct elf_final_link_info *flinfo, bfd *input_bfd) /* Get the swapped relocs. */ internal_relocs - = _bfd_elf_link_read_relocs (input_bfd, o, flinfo->external_relocs, - flinfo->internal_relocs, false); + = _bfd_elf_link_info_read_relocs (input_bfd, flinfo->info, o, + flinfo->external_relocs, + flinfo->internal_relocs, + false); if (internal_relocs == NULL && o->reloc_count > 0) return false; @@ -13279,8 +13306,12 @@ init_reloc_cookie (struct elf_reloc_cookie *cookie, info->callbacks->einfo (_("%P%X: can not read symbols: %E\n")); return false; } - if (info->keep_memory) - symtab_hdr->contents = (bfd_byte *) cookie->locsyms; + if (_bfd_link_keep_memory (info) ) + { + symtab_hdr->contents = (bfd_byte *) cookie->locsyms; + info->cache_size += (cookie->locsymcount + * sizeof (Elf_External_Sym_Shndx)); + } } return true; } @@ -13312,8 +13343,9 @@ init_reloc_cookie_rels (struct elf_reloc_cookie *cookie, } else { - cookie->rels = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL, - info->keep_memory); + cookie->rels = _bfd_elf_link_info_read_relocs (abfd, info, sec, + NULL, NULL, + _bfd_link_keep_memory (info)); if (cookie->rels == NULL) return false; cookie->rel = cookie->rels; @@ -13881,14 +13913,22 @@ elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp) return true; } +struct link_info_ok +{ + struct bfd_link_info *info; + bool ok; +}; + static bool -elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp) +elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, + void *ptr) { asection *sec; bfd_vma hstart, hend; Elf_Internal_Rela *relstart, *relend, *rel; const struct elf_backend_data *bed; unsigned int log_file_align; + struct link_info_ok *info = (struct link_info_ok *) ptr; /* Take care of both those symbols that do not describe vtables as well as those that are not loaded. */ @@ -13904,9 +13944,10 @@ elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp) hstart = h->root.u.def.value; hend = hstart + h->size; - relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, NULL, true); + relstart = _bfd_elf_link_info_read_relocs (sec->owner, info->info, + sec, NULL, NULL, true); if (!relstart) - return *(bool *) okp = false; + return info->ok = false; bed = get_elf_backend_data (sec->owner); log_file_align = bed->s->log_file_align; @@ -14029,6 +14070,7 @@ bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info) elf_gc_mark_hook_fn gc_mark_hook; const struct elf_backend_data *bed = get_elf_backend_data (abfd); struct elf_link_hash_table *htab; + struct link_info_ok info_ok; if (!bed->can_gc_sections || !is_elf_hash_table (info->hash)) @@ -14070,8 +14112,10 @@ bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info) return false; /* Kill the vtable relocations that were not used. */ - elf_link_hash_traverse (htab, elf_gc_smash_unused_vtentry_relocs, &ok); - if (!ok) + info_ok.info = info; + info_ok.ok = true; + elf_link_hash_traverse (htab, elf_gc_smash_unused_vtentry_relocs, &info_ok); + if (!info_ok.ok) return false; /* Mark dynamically referenced symbols. */ diff --git a/bfd/libbfd-in.h b/bfd/libbfd-in.h index 1f7e22186ec..89d2997aedf 100644 --- a/bfd/libbfd-in.h +++ b/bfd/libbfd-in.h @@ -894,6 +894,9 @@ extern bfd_byte * _bfd_write_unsigned_leb128 extern struct bfd_link_info *_bfd_get_link_info (bfd *); +extern bool _bfd_link_keep_memory (struct bfd_link_info *) + ATTRIBUTE_HIDDEN; + #if GCC_VERSION >= 7000 #define _bfd_mul_overflow(a, b, res) __builtin_mul_overflow (a, b, res) #else diff --git a/bfd/libbfd.h b/bfd/libbfd.h index c37ddc03cfd..69496411622 100644 --- a/bfd/libbfd.h +++ b/bfd/libbfd.h @@ -899,6 +899,9 @@ extern bfd_byte * _bfd_write_unsigned_leb128 extern struct bfd_link_info *_bfd_get_link_info (bfd *); +extern bool _bfd_link_keep_memory (struct bfd_link_info *) + ATTRIBUTE_HIDDEN; + #if GCC_VERSION >= 7000 #define _bfd_mul_overflow(a, b, res) __builtin_mul_overflow (a, b, res) #else diff --git a/bfd/linker.c b/bfd/linker.c index c350cd3fd15..755ff19923b 100644 --- a/bfd/linker.c +++ b/bfd/linker.c @@ -3535,3 +3535,38 @@ _bfd_nolink_bfd_define_start_stop (struct bfd_link_info *info ATTRIBUTE_UNUSED, { return (struct bfd_link_hash_entry *) _bfd_ptr_bfd_null_error (sec->owner); } + +/* Return false if linker should avoid caching relocation infomation + and symbol tables of input files in memory. */ + +bool +_bfd_link_keep_memory (struct bfd_link_info * info) +{ + bfd *abfd; + bfd_size_type size; + + if (!info->keep_memory) + return false; + + if (info->max_cache_size == (bfd_size_type) -1) + return true; + + abfd = info->input_bfds; + size = info->cache_size; + do + { + if (size >= info->max_cache_size) + { + /* Over the limit. Reduce the memory usage. */ + info->keep_memory = false; + return false; + } + if (!abfd) + break; + size += abfd->alloc_size; + abfd = abfd->link.next; + } + while (1); + + return true; +} diff --git a/bfd/opncls.c b/bfd/opncls.c index 4fb79324c0a..96ff1e9f6a9 100644 --- a/bfd/opncls.c +++ b/bfd/opncls.c @@ -1032,6 +1032,8 @@ bfd_alloc (bfd *abfd, bfd_size_type size) ret = objalloc_alloc ((struct objalloc *) abfd->memory, ul_size); if (ret == NULL) bfd_set_error (bfd_error_no_memory); + else + abfd->alloc_size += size; return ret; } diff --git a/include/bfdlink.h b/include/bfdlink.h index 7f1b12dbf37..54968585410 100644 --- a/include/bfdlink.h +++ b/include/bfdlink.h @@ -682,6 +682,13 @@ struct bfd_link_info /* The version information. */ struct bfd_elf_version_tree *version_info; + + /* Size of cache. Backend can use it to keep strace cache size. */ + bfd_size_type cache_size; + + /* The maximum cache size. Backend can use cache_size and and + max_cache_size to decide if keep_memory should be honored. */ + bfd_size_type max_cache_size; }; /* Some forward-definitions used by some callbacks. */ diff --git a/ld/NEWS b/ld/NEWS index 11bc5745ebf..92dd4fd97cd 100644 --- a/ld/NEWS +++ b/ld/NEWS @@ -1,5 +1,8 @@ -*- text -*- +* Add --max-cache-size=SIZE to set the the maximum cache size to SIZE + bytes. + Changes in 2.37: * arm-symbianelf support removed. diff --git a/ld/ld.texi b/ld/ld.texi index dd8f571d4e4..67c50839b37 100644 --- a/ld/ld.texi +++ b/ld/ld.texi @@ -2839,6 +2839,12 @@ has been used. The @option{--reduce-memory-overheads} switch may be also be used to enable other tradeoffs in future versions of the linker. +@kindex --max-cache-size=@var{size} +@item --max-cache-size=@var{size} +@command{ld} normally caches the relocation information and symbol tables +of input files in memory with the unlimited size. This option sets the +maximum cache size to @var{size}. + @kindex --build-id @kindex --build-id=@var{style} @item --build-id diff --git a/ld/ldlex.h b/ld/ldlex.h index 9e8bf5fb835..9707d57caf8 100644 --- a/ld/ldlex.h +++ b/ld/ldlex.h @@ -140,6 +140,7 @@ enum option_values OPTION_WARN_TEXTREL, OPTION_WARN_ALTERNATE_EM, OPTION_REDUCE_MEMORY_OVERHEADS, + OPTION_MAX_CACHE_SIZE, #if BFD_SUPPORTS_PLUGINS OPTION_PLUGIN, OPTION_PLUGIN_OPT, diff --git a/ld/ldmain.c b/ld/ldmain.c index 42660eb9a3c..e4c67740e37 100644 --- a/ld/ldmain.c +++ b/ld/ldmain.c @@ -331,6 +331,7 @@ main (int argc, char **argv) link_info.allow_undefined_version = true; link_info.keep_memory = true; + link_info.max_cache_size = (bfd_size_type) -1; link_info.combreloc = true; link_info.strip_discarded = true; link_info.prohibit_multiple_definition_absolute = false; diff --git a/ld/lexsup.c b/ld/lexsup.c index 00274c500d0..c128fe3a96b 100644 --- a/ld/lexsup.c +++ b/ld/lexsup.c @@ -433,6 +433,10 @@ static const struct ld_option ld_options[] = OPTION_REDUCE_MEMORY_OVERHEADS}, '\0', NULL, N_("Reduce memory overheads, possibly taking much longer"), TWO_DASHES }, + { {"max-cache-size=SIZE", required_argument, NULL, + OPTION_MAX_CACHE_SIZE}, + '\0', NULL, N_("Set the maximum cache size to SIZE bytes"), + TWO_DASHES }, { {"relax", no_argument, NULL, OPTION_RELAX}, '\0', NULL, N_("Reduce code size by using target specific optimizations"), TWO_DASHES }, { {"no-relax", no_argument, NULL, OPTION_NO_RELAX}, @@ -1631,6 +1635,17 @@ parse_args (unsigned argc, char **argv) config.hash_table_size = 1021; break; + case OPTION_MAX_CACHE_SIZE: + { + char *end; + bfd_size_type cache_size = strtoul (optarg, &end, 0); + if (*end != '\0') + einfo (_("%F%P: invalid cache memory size: %s\n"), + optarg); + link_info.max_cache_size = cache_size; + } + break; + case OPTION_HASH_SIZE: { bfd_size_type new_size; diff --git a/ld/testsuite/ld-bootstrap/bootstrap.exp b/ld/testsuite/ld-bootstrap/bootstrap.exp index b21b48ab20e..9c27c5ff5d9 100644 --- a/ld/testsuite/ld-bootstrap/bootstrap.exp +++ b/ld/testsuite/ld-bootstrap/bootstrap.exp @@ -55,7 +55,8 @@ if [check_plugin_api_available] { # really test -r. Use ld1 to link a fresh ld, ld2. Use ld2 to link a # new ld, ld3. ld2 and ld3 should be identical. set test_flags {"" "strip" "--static" "-Wl,--traditional-format" - "-Wl,--no-keep-memory" "-Wl,--relax"} + "-Wl,--no-keep-memory" "-Wl,--relax" + "-Wl,--max-cache-size=-1"} if { [istarget "powerpc-*-*"] } { lappend test_flags "-Wl,--ppc476-workaround" } -- 2.30.2