diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2020-03-12 12:17:38 +0300 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2020-03-25 20:28:30 +0300 |
| commit | cdb3d057a17d56363a831e486ea39e4c389a6cf9 (patch) | |
| tree | 87c68d4378ff885e3efaba3cbad947f100c1c071 /tools/objtool | |
| parent | 513b5ca6b5fbeb766999fb1a4bc9a55c9fb7c9ca (diff) | |
| download | linux-cdb3d057a17d56363a831e486ea39e4c389a6cf9.tar.xz | |
objtool: Optimize find_symbol_by_name()
Perf showed that find_symbol_by_name() takes time; add a symbol name
hash.
This shaves another second off of objtool on vmlinux.o runtime, down
to 15 seconds.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200324160924.676865656@infradead.org
Diffstat (limited to 'tools/objtool')
| -rw-r--r-- | tools/objtool/elf.c | 10 | ||||
| -rw-r--r-- | tools/objtool/elf.h | 2 |
2 files changed, 7 insertions, 5 deletions
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c index 07db4df18588..43abae763b3b 100644 --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -203,13 +203,11 @@ struct symbol *find_func_containing(struct section *sec, unsigned long offset) struct symbol *find_symbol_by_name(struct elf *elf, const char *name) { - struct section *sec; struct symbol *sym; - list_for_each_entry(sec, &elf->sections, list) - list_for_each_entry(sym, &sec->symbol_list, list) - if (!strcmp(sym->name, name)) - return sym; + hash_for_each_possible(elf->symbol_name_hash, sym, name_hash, str_hash(name)) + if (!strcmp(sym->name, name)) + return sym; return NULL; } @@ -386,6 +384,7 @@ static int read_symbols(struct elf *elf) entry = &sym->sec->symbol_list; list_add(&sym->list, entry); hash_add(elf->symbol_hash, &sym->hash, sym->idx); + hash_add(elf->symbol_name_hash, &sym->name_hash, str_hash(sym->name)); } if (stats) @@ -524,6 +523,7 @@ struct elf *elf_read(const char *name, int flags) memset(elf, 0, sizeof(*elf)); hash_init(elf->symbol_hash); + hash_init(elf->symbol_name_hash); hash_init(elf->section_hash); hash_init(elf->section_name_hash); INIT_LIST_HEAD(&elf->sections); diff --git a/tools/objtool/elf.h b/tools/objtool/elf.h index d18f466829b0..3088d925d640 100644 --- a/tools/objtool/elf.h +++ b/tools/objtool/elf.h @@ -47,6 +47,7 @@ struct symbol { struct list_head list; struct rb_node node; struct hlist_node hash; + struct hlist_node name_hash; GElf_Sym sym; struct section *sec; char *name; @@ -77,6 +78,7 @@ struct elf { char *name; struct list_head sections; DECLARE_HASHTABLE(symbol_hash, 20); + DECLARE_HASHTABLE(symbol_name_hash, 20); DECLARE_HASHTABLE(section_hash, 16); DECLARE_HASHTABLE(section_name_hash, 16); }; |