From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 549AAC41621 for ; Tue, 24 Mar 2020 16:11:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E2ED0208E0 for ; Tue, 24 Mar 2020 16:11:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="oON9T2l8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728816AbgCXQLv (ORCPT ); Tue, 24 Mar 2020 12:11:51 -0400 Received: from merlin.infradead.org ([205.233.59.134]:36990 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728507AbgCXQLh (ORCPT ); Tue, 24 Mar 2020 12:11:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-Id:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=vZGTNFI1qsH9Qyn4to0UBz3pVYWZFo5oK0ajBpNGby8=; b=oON9T2l8FCWtD42rmjdZCCcfKz kWPt9eZig5yKikujiCYoxZG9iit+xQj/l3DGpT3pXsudAFDQP7mEyD7pWDx9gTiiTZdrR3KOljX6c ndqIZf+Keze959ayTQkugGR55YL68hr8tN2dn85OZcLU/SV/wQv9rTOwxq9EMeemYVhLPOw37sPyz uxpGVWz79XW9t7gQyprDinPELp0L4ZpL0ru4f/9d7NhWZfUjS4lhdqlZ8fd1GDVF1AvI8gq8xu63G UjQtIKXrBDT2/M/TqiE4TiU45qw7S6H1KqvPyRplUACg7Azkbmn0shpH5xoZQE1pmGuiaadivEExY rABS7JgA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jGm9M-0006c1-Uf; Tue, 24 Mar 2020 16:11:33 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 6B9AF307444; Tue, 24 Mar 2020 17:11:28 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 5ECCD29A490F9; Tue, 24 Mar 2020 17:11:28 +0100 (CET) Message-Id: <20200324160925.107835416@infradead.org> User-Agent: quilt/0.65 Date: Tue, 24 Mar 2020 16:31:33 +0100 From: Peter Zijlstra To: tglx@linutronix.de, jpoimboe@redhat.com Cc: linux-kernel@vger.kernel.org, x86@kernel.org, peterz@infradead.org, mhiramat@kernel.org, mbenes@suse.cz, brgerst@gmail.com Subject: [PATCH v3 20/26] objtool: Optimize !vmlinux.o again References: <20200324153113.098167666@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When doing kbuild tests to see if the objtool changes affected those I found that there was a measurable regression: pre post real 1m13.594 1m16.488s user 34m58.246s 35m23.947s sys 4m0.393s 4m27.312s Perf showed that for small files the increased hash-table sizes were a measurable difference. Since we already have -l "vmlinux" to distinguish between the modes, make it also use a smaller portion of the hash-tables. This flips it into a small win: real 1m14.143s user 34m49.292s sys 3m44.746s Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf --- tools/objtool/elf.c | 62 +++++++++++++++++++++++++++++++++--------------- tools/objtool/elf.h | 13 ++++++---- tools/objtool/orc_gen.c | 3 -- 3 files changed, 52 insertions(+), 26 deletions(-) --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -27,6 +27,22 @@ static inline u32 str_hash(const char *s return jhash(str, strlen(str), 0); } +static inline int elf_hash_bits(void) +{ + return vmlinux ? ELF_HASH_BITS : 16; +} + +#define elf_hash_add(hashtable, node, key) \ + hlist_add_head(node, &hashtable[hash_min(key, elf_hash_bits())]) + +static void elf_hash_init(struct hlist_head *table) +{ + __hash_init(table, 1U << elf_hash_bits()); +} + +#define elf_hash_for_each_possible(name, obj, member, key) \ + hlist_for_each_entry(obj, &name[hash_min(key, elf_hash_bits())], member) + static void rb_add(struct rb_root *tree, struct rb_node *node, int (*cmp)(struct rb_node *, const struct rb_node *)) { @@ -115,7 +131,7 @@ struct section *find_section_by_name(str { struct section *sec; - hash_for_each_possible(elf->section_name_hash, sec, name_hash, str_hash(name)) + elf_hash_for_each_possible(elf->section_name_hash, sec, name_hash, str_hash(name)) if (!strcmp(sec->name, name)) return sec; @@ -127,7 +143,7 @@ static struct section *find_section_by_i { struct section *sec; - hash_for_each_possible(elf->section_hash, sec, hash, idx) + elf_hash_for_each_possible(elf->section_hash, sec, hash, idx) if (sec->idx == idx) return sec; @@ -138,7 +154,7 @@ static struct symbol *find_symbol_by_ind { struct symbol *sym; - hash_for_each_possible(elf->symbol_hash, sym, hash, idx) + elf_hash_for_each_possible(elf->symbol_hash, sym, hash, idx) if (sym->idx == idx) return sym; @@ -205,7 +221,7 @@ struct symbol *find_symbol_by_name(struc { struct symbol *sym; - hash_for_each_possible(elf->symbol_name_hash, sym, name_hash, str_hash(name)) + elf_hash_for_each_possible(elf->symbol_name_hash, sym, name_hash, str_hash(name)) if (!strcmp(sym->name, name)) return sym; @@ -224,7 +240,7 @@ struct rela *find_rela_by_dest_range(str sec = sec->rela; for_offset_range(o, offset, offset + len) { - hash_for_each_possible(elf->rela_hash, rela, hash, + elf_hash_for_each_possible(elf->rela_hash, rela, hash, sec_offset_hash(sec, o)) { if (rela->sec != sec) continue; @@ -309,8 +325,8 @@ static int read_sections(struct elf *elf sec->len = sec->sh.sh_size; list_add_tail(&sec->list, &elf->sections); - hash_add(elf->section_hash, &sec->hash, sec->idx); - hash_add(elf->section_name_hash, &sec->name_hash, str_hash(sec->name)); + elf_hash_add(elf->section_hash, &sec->hash, sec->idx); + elf_hash_add(elf->section_name_hash, &sec->name_hash, str_hash(sec->name)); } if (stats) @@ -394,8 +410,8 @@ static int read_symbols(struct elf *elf) else 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)); + elf_hash_add(elf->symbol_hash, &sym->hash, sym->idx); + elf_hash_add(elf->symbol_name_hash, &sym->name_hash, str_hash(sym->name)); } if (stats) @@ -456,6 +472,14 @@ static int read_symbols(struct elf *elf) return -1; } +void elf_add_rela(struct elf *elf, struct rela *rela) +{ + struct section *sec = rela->sec; + + list_add_tail(&rela->list, &sec->rela_list); + elf_hash_add(elf->rela_hash, &rela->hash, rela_hash(rela)); +} + static int read_relas(struct elf *elf) { struct section *sec; @@ -503,8 +527,7 @@ static int read_relas(struct elf *elf) return -1; } - list_add_tail(&rela->list, &sec->rela_list); - hash_add(elf->rela_hash, &rela->hash, rela_hash(rela)); + elf_add_rela(elf, rela); nr_rela++; } max_rela = max(max_rela, nr_rela); @@ -531,15 +554,16 @@ struct elf *elf_read(const char *name, i perror("malloc"); return NULL; } - memset(elf, 0, sizeof(*elf)); + memset(elf, 0, offsetof(struct elf, sections)); - hash_init(elf->symbol_hash); - hash_init(elf->symbol_name_hash); - hash_init(elf->section_hash); - hash_init(elf->section_name_hash); - hash_init(elf->rela_hash); INIT_LIST_HEAD(&elf->sections); + elf_hash_init(elf->symbol_hash); + elf_hash_init(elf->symbol_name_hash); + elf_hash_init(elf->section_hash); + elf_hash_init(elf->section_name_hash); + elf_hash_init(elf->rela_hash); + elf->fd = open(name, flags); if (elf->fd == -1) { fprintf(stderr, "objtool: Can't open '%s': %s\n", @@ -676,8 +700,8 @@ struct section *elf_create_section(struc shstrtab->changed = true; list_add_tail(&sec->list, &elf->sections); - hash_add(elf->section_hash, &sec->hash, sec->idx); - hash_add(elf->section_name_hash, &sec->name_hash, str_hash(sec->name)); + elf_hash_add(elf->section_hash, &sec->hash, sec->idx); + elf_hash_add(elf->section_name_hash, &sec->name_hash, str_hash(sec->name)); return sec; } --- a/tools/objtool/elf.h +++ b/tools/objtool/elf.h @@ -70,17 +70,19 @@ struct rela { bool jump_table_start; }; +#define ELF_HASH_BITS 20 + struct elf { Elf *elf; GElf_Ehdr ehdr; int fd; 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); - DECLARE_HASHTABLE(rela_hash, 20); + DECLARE_HASHTABLE(symbol_hash, ELF_HASH_BITS); + DECLARE_HASHTABLE(symbol_name_hash, ELF_HASH_BITS); + DECLARE_HASHTABLE(section_hash, ELF_HASH_BITS); + DECLARE_HASHTABLE(section_name_hash, ELF_HASH_BITS); + DECLARE_HASHTABLE(rela_hash, ELF_HASH_BITS); }; #define OFFSET_STRIDE_BITS 4 @@ -127,6 +129,7 @@ struct section *elf_create_rela_section( int elf_rebuild_rela_section(struct section *sec); int elf_write(struct elf *elf); void elf_close(struct elf *elf); +void elf_add_rela(struct elf *elf, struct rela *rela); #define for_each_sec(file, sec) \ list_for_each_entry(sec, &file->elf->sections, list) --- a/tools/objtool/orc_gen.c +++ b/tools/objtool/orc_gen.c @@ -111,8 +111,7 @@ static int create_orc_entry(struct elf * rela->offset = idx * sizeof(int); rela->sec = ip_relasec; - list_add_tail(&rela->list, &ip_relasec->rela_list); - hash_add(elf->rela_hash, &rela->hash, rela_hash(rela)); + elf_add_rela(elf, rela); return 0; }