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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 77919C433E1 for ; Tue, 2 Jun 2020 19:52:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5F6E92072F for ; Tue, 2 Jun 2020 19:52:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728361AbgFBTvC (ORCPT ); Tue, 2 Jun 2020 15:51:02 -0400 Received: from ex13-edg-ou-002.vmware.com ([208.91.0.190]:36862 "EHLO EX13-EDG-OU-002.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728123AbgFBTu5 (ORCPT ); Tue, 2 Jun 2020 15:50:57 -0400 Received: from sc9-mailhost3.vmware.com (10.113.161.73) by EX13-EDG-OU-002.vmware.com (10.113.208.156) with Microsoft SMTP Server id 15.0.1156.6; Tue, 2 Jun 2020 12:50:52 -0700 Received: from sc9-mailhost3.vmware.com (unknown [10.200.192.49]) by sc9-mailhost3.vmware.com (Postfix) with ESMTP id D95A240BED; Tue, 2 Jun 2020 12:50:52 -0700 (PDT) From: Matt Helsley To: CC: Josh Poimboeuf , Peter Zijlstra , Steven Rostedt , Sami Tolvanen , Julien Thierry , Kamalesh Babulal , Matt Helsley Subject: [RFC][PATCH v4 08/32] objtool: mcount: Walk objtool Elf structs in find_secsym_ndx Date: Tue, 2 Jun 2020 12:50:01 -0700 Message-ID: <23497cb675be990627fa76eed26c1385cb0f5826.1591125127.git.mhelsley@vmware.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII Received-SPF: None (EX13-EDG-OU-002.vmware.com: mhelsley@vmware.com does not designate permitted sender hosts) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Rather than using indices into raw ELF32/64 tables mapped for the wrapper, use the objtool functions to find the a suitable symbol in the given text section. Also take advantage of this commit to rename the function to something that reads more easily. Signed-off-by: Matt Helsley --- tools/objtool/recordmcount.c | 2 ++ tools/objtool/recordmcount.h | 42 ++++++++++++++++-------------------- 2 files changed, 21 insertions(+), 23 deletions(-) diff --git a/tools/objtool/recordmcount.c b/tools/objtool/recordmcount.c index f20582ac99e2..843027a46e1b 100644 --- a/tools/objtool/recordmcount.c +++ b/tools/objtool/recordmcount.c @@ -422,6 +422,8 @@ static int is_mcounted_section_name(char const *const txtname) strcmp(".cpuidle.text", txtname) == 0; } +static const unsigned int missing_sym = (unsigned int)-1; + /* 32 bit and 64 bit are very similar */ #include "recordmcount.h" #define RECORD_MCOUNT_64 diff --git a/tools/objtool/recordmcount.h b/tools/objtool/recordmcount.h index b487308992ce..dba1c385106f 100644 --- a/tools/objtool/recordmcount.h +++ b/tools/objtool/recordmcount.h @@ -24,7 +24,7 @@ #undef mcount_adjust #undef sift_rel_mcount #undef nop_mcount -#undef find_secsym_ndx +#undef find_section_sym_index #undef has_rel_mcount #undef tot_relsize #undef get_mcountsym @@ -53,7 +53,7 @@ # define append_func append64 # define sift_rel_mcount sift64_rel_mcount # define nop_mcount nop_mcount_64 -# define find_secsym_ndx find64_secsym_ndx +# define find_section_sym_index find64_section_sym_index # define has_rel_mcount has64_rel_mcount # define tot_relsize tot64_relsize # define get_sym_str_and_relp get_sym_str_and_relp_64 @@ -85,7 +85,7 @@ # define append_func append32 # define sift_rel_mcount sift32_rel_mcount # define nop_mcount nop_mcount_32 -# define find_secsym_ndx find32_secsym_ndx +# define find_section_sym_index find32_section_sym_index # define has_rel_mcount has32_rel_mcount # define tot_relsize tot32_relsize # define get_sym_str_and_relp get_sym_str_and_relp_32 @@ -427,38 +427,36 @@ static int nop_mcount(const struct section * const rels, * Num: Value Size Type Bind Vis Ndx Name * 2: 00000000 0 SECTION LOCAL DEFAULT 1 */ -static int find_secsym_ndx(unsigned const txtndx, +static int find_section_sym_index(unsigned const txtndx, char const *const txtname, uint_t *const recvalp, unsigned int *sym_index, - Elf_Shdr const *const symhdr, Elf_Ehdr const *const ehdr) { - Elf_Sym const *const sym0 = (Elf_Sym const *)(_w(symhdr->sh_offset) - + (void *)ehdr); - unsigned const nsym = _w(symhdr->sh_size) / _w(symhdr->sh_entsize); - Elf_Sym const *symp; - unsigned t; + struct symbol *sym; + struct section *txts = find_section_by_index(lf, txtndx); - for (symp = sym0, t = nsym; t; --t, ++symp) { - unsigned int const st_bind = ELF_ST_BIND(symp->st_info); + if (!txts) { + fprintf(stderr, "Cannot find section %u: %s.\n", + txtndx, txtname); + return missing_sym; + } - if (txtndx == w2(symp->st_shndx) - /* avoid STB_WEAK */ - && (STB_LOCAL == st_bind || STB_GLOBAL == st_bind)) { + list_for_each_entry(sym, &txts->symbol_list, list) { + if ((sym->bind == STB_LOCAL) || (sym->bind == STB_GLOBAL)) { /* function symbols on ARM have quirks, avoid them */ if (w2(ehdr->e_machine) == EM_ARM - && ELF_ST_TYPE(symp->st_info) == STT_FUNC) + && sym->type == STT_FUNC) continue; - *recvalp = _w(symp->st_value); - *sym_index = symp - sym0; + *recvalp = sym->sym.st_value; + *sym_index = sym->idx; return 0; } } fprintf(stderr, "Cannot find symbol for section %u: %s.\n", txtndx, txtname); - return -1; + return missing_sym; } static char const *has_rel_mcount(const struct section * const rels) @@ -540,10 +538,8 @@ static int do_func(Elf_Ehdr *const ehdr, uint_t recval = 0; symsec_sh_link = sec->sh.sh_link; - result = find_secsym_ndx(sec->sh.sh_info, txtname, - &recval, &recsym, - &shdr0[symsec_sh_link], - ehdr); + result = find_section_sym_index(sec->sh.sh_info, + txtname, &recval, &recsym, ehdr); if (result) goto out; -- 2.20.1