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 EFDDDC10F29 for ; Tue, 17 Mar 2020 17:12:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C3EE520714 for ; Tue, 17 Mar 2020 17:12:06 +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="pwbWJsYn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726801AbgCQRMF (ORCPT ); Tue, 17 Mar 2020 13:12:05 -0400 Received: from merlin.infradead.org ([205.233.59.134]:45190 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726777AbgCQRMD (ORCPT ); Tue, 17 Mar 2020 13:12:03 -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=y5WuxwMAJr0QbwswmI2HKoXsNzUzxuLM0YdKzeroCPc=; b=pwbWJsYnNQWwA52qMB338tze3a 2Xbl6hOiXoQRfhXstTGAow/OZWjiPWX6NhZrP+LcFukLDUGvf/vfH/3naLQQ0QUlzJdQwc+PO7cPD ec9g/+kJEcW/rSFucDtBzIm0YddT7QiM9tD/VPb+dMTrx4KE+7kS0TIL9DYdnAaRRodp4RWWT8FEx EooZ1li3d3SOALNlebT97DNXKU2D3lXVV5ZABiY/MY/lF9dU/yESLZ0VjPMJSlW3H8q6FsW5N+kDa I/N/0jHg4QtcuJR44bjy57j+7eZXOVK+Cvt4Y6ilRj1pWwkypwIXK1LE43ArdrDHbuIb5G/k0V4pu hNEei30w==; 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 1jEFkz-0003ir-Ly; Tue, 17 Mar 2020 17:11:57 +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 0FE553071A3; Tue, 17 Mar 2020 18:11:55 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 022C5264FDB18; Tue, 17 Mar 2020 18:11:55 +0100 (CET) Message-Id: <20200317170910.475238692@infradead.org> User-Agent: quilt/0.65 Date: Tue, 17 Mar 2020 18:02:46 +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 v2 12/19] objtool: Optimize find_symbol_by_name() References: <20200317170234.897520633@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 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) --- tools/objtool/elf.c | 10 +++++----- tools/objtool/elf.h | 2 ++ 2 files changed, 7 insertions(+), 5 deletions(-) --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -203,13 +203,11 @@ struct symbol *find_func_containing(stru 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, i 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); --- 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); };