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=-9.7 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 2D0B8C433E0 for ; Thu, 18 Jun 2020 20:39:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0E88420890 for ; Thu, 18 Jun 2020 20:39:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731159AbgFRUjO (ORCPT ); Thu, 18 Jun 2020 16:39:14 -0400 Received: from ex13-edg-ou-001.vmware.com ([208.91.0.189]:3944 "EHLO EX13-EDG-OU-001.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726382AbgFRUjE (ORCPT ); Thu, 18 Jun 2020 16:39:04 -0400 Received: from sc9-mailhost2.vmware.com (10.113.161.72) by EX13-EDG-OU-001.vmware.com (10.113.208.155) with Microsoft SMTP Server id 15.0.1156.6; Thu, 18 Jun 2020 13:38:59 -0700 Received: from sc9-mailhost2.vmware.com (unknown [10.129.221.29]) by sc9-mailhost2.vmware.com (Postfix) with ESMTP id 398D4B2660; Thu, 18 Jun 2020 16:39:03 -0400 (EDT) From: Matt Helsley To: CC: Josh Poimboeuf , Peter Zijlstra , Steven Rostedt , Julien Thierry , Kamalesh Babulal , Matt Helsley Subject: [RFC][PATCH v5 06/51] objtool: recordmcount: Convert do_func() relhdrs Date: Thu, 18 Jun 2020 13:37:52 -0700 Message-ID: X-Mailer: git-send-email 2.25.4 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-001.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 Use objtool's ELF data structures to visit the relocation sections in the top-level ELF file walking function, do_func(). This means we can pass pointers to the relocation header structures into nested functions and avoid the indexing patterns for them. These conversions don't use libelf/objtool to modify the ELF file -- it only changes the way we walk the ELF sections and do lookups to find the relocations. Signed-off-by: Matt Helsley --- tools/objtool/recordmcount.h | 61 +++++++++++++++++++----------------- 1 file changed, 32 insertions(+), 29 deletions(-) diff --git a/tools/objtool/recordmcount.h b/tools/objtool/recordmcount.h index a96ffcef515a..b46e855d32bf 100644 --- a/tools/objtool/recordmcount.h +++ b/tools/objtool/recordmcount.h @@ -364,7 +364,7 @@ static unsigned get_mcountsym(Elf_Sym const *const sym0, return mcountsym; } -static void get_sym_str_and_relp(Elf_Shdr const *const relhdr, +static void get_sym_str_and_relp(GElf_Shdr const *const relhdr, Elf_Ehdr const *const ehdr, Elf_Sym const **sym0, char const **str0, @@ -372,10 +372,10 @@ static void get_sym_str_and_relp(Elf_Shdr const *const relhdr, { Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff) + (void *)ehdr); - unsigned const symsec_sh_link = w(relhdr->sh_link); + unsigned const symsec_sh_link = relhdr->sh_link; Elf_Shdr const *const symsec = &shdr0[symsec_sh_link]; Elf_Shdr const *const strsec = &shdr0[w(symsec->sh_link)]; - Elf_Rel const *const rel0 = (Elf_Rel const *)(_w(relhdr->sh_offset) + Elf_Rel const *const rel0 = (Elf_Rel const *)(relhdr->sh_offset + (void *)ehdr); *sym0 = (Elf_Sym const *)(_w(symsec->sh_offset) @@ -395,9 +395,9 @@ static void get_sym_str_and_relp(Elf_Shdr const *const relhdr, static uint_t *sift_rel_mcount(uint_t *mlocp, unsigned const offbase, Elf_Rel **const mrelpp, - Elf_Shdr const *const relhdr, + GElf_Shdr const *const relhdr, Elf_Ehdr const *const ehdr, - unsigned const recsym, + unsigned const recsym_index, uint_t const recval, unsigned const reltype) { @@ -406,8 +406,8 @@ static uint_t *sift_rel_mcount(uint_t *mlocp, Elf_Sym const *sym0; char const *str0; Elf_Rel const *relp; - unsigned rel_entsize = _w(relhdr->sh_entsize); - unsigned const nrel = _w(relhdr->sh_size) / rel_entsize; + unsigned int rel_entsize = relhdr->sh_entsize; + unsigned const nrel = relhdr->sh_size / rel_entsize; unsigned mcountsym = 0; unsigned t; @@ -423,7 +423,7 @@ static uint_t *sift_rel_mcount(uint_t *mlocp, _w(_w(relp->r_offset) - recval + mcount_adjust); mrelp->r_offset = _w(offbase + ((void *)mlocp - (void *)mloc0)); - Elf_r_info(mrelp, recsym, reltype); + Elf_r_info(mrelp, recsym_index, reltype); if (rel_entsize == sizeof(Elf_Rela)) { ((Elf_Rela *)mrelp)->r_addend = addend; *mlocp++ = 0; @@ -443,7 +443,7 @@ static uint_t *sift_rel_mcount(uint_t *mlocp, * that are not going to be traced. The mcount calls here will be converted * into nops. */ -static int nop_mcount(Elf_Shdr const *const relhdr, +static int nop_mcount(GElf_Shdr const *const relhdr, Elf_Ehdr const *const ehdr, const char *const txtname) { @@ -452,9 +452,9 @@ static int nop_mcount(Elf_Shdr const *const relhdr, Elf_Sym const *sym0; char const *str0; Elf_Rel const *relp; - Elf_Shdr const *const shdr = &shdr0[w(relhdr->sh_info)]; - unsigned rel_entsize = _w(relhdr->sh_entsize); - unsigned const nrel = _w(relhdr->sh_size) / rel_entsize; + Elf_Shdr const *const shdr = &shdr0[relhdr->sh_info]; + unsigned int rel_entsize = relhdr->sh_entsize; + unsigned const nrel = relhdr->sh_size / rel_entsize; unsigned mcountsym = 0; unsigned t; int once = 0; @@ -545,13 +545,13 @@ static int find_secsym_ndx(unsigned const txtndx, } /* Evade ISO C restriction: no declaration after statement in has_rel_mcount. */ -static char const * __has_rel_mcount(Elf_Shdr const *const relhdr, /* reltype */ +static char const * __has_rel_mcount(GElf_Shdr const *const relhdr, /* reltype */ Elf_Shdr const *const shdr0, char const *const shstrtab, char const *const fname) { /* .sh_info depends on .sh_type == SHT_REL[,A] */ - Elf_Shdr const *const txthdr = &shdr0[w(relhdr->sh_info)]; + Elf_Shdr const *const txthdr = &shdr0[relhdr->sh_info]; char const *const txtname = &shstrtab[w(txthdr->sh_name)]; if (w(txthdr->sh_type) != SHT_PROGBITS || @@ -560,30 +560,29 @@ static char const * __has_rel_mcount(Elf_Shdr const *const relhdr, /* reltype */ return txtname; } -static char const *has_rel_mcount(Elf_Shdr const *const relhdr, +static char const *has_rel_mcount(GElf_Shdr const *const relhdr, Elf_Shdr const *const shdr0, char const *const shstrtab, char const *const fname) { - if (w(relhdr->sh_type) != SHT_REL && w(relhdr->sh_type) != SHT_RELA) + if (relhdr->sh_type != SHT_REL && relhdr->sh_type != SHT_RELA) return NULL; return __has_rel_mcount(relhdr, shdr0, shstrtab, fname); } static unsigned tot_relsize(Elf_Shdr const *const shdr0, - unsigned nhdr, const char *const shstrtab, const char *const fname) { + struct section *sec; unsigned totrelsz = 0; - Elf_Shdr const *shdrp = shdr0; char const *txtname; - for (; nhdr; --nhdr, ++shdrp) { - txtname = has_rel_mcount(shdrp, shdr0, shstrtab, fname); + list_for_each_entry(sec, &lf->sections, list) { + txtname = has_rel_mcount(&sec->sh, shdr0, shstrtab, fname); if (txtname && is_mcounted_section_name(txtname)) - totrelsz += _w(shdrp->sh_size); + totrelsz += sec->sh.sh_size; } return totrelsz; } @@ -599,8 +598,7 @@ static int do_func(Elf_Ehdr *const ehdr, char const *const fname, char const *const shstrtab = (char const *)(_w(shstr->sh_offset) + (void *)ehdr); - Elf_Shdr const *relhdr; - unsigned k; + GElf_Shdr const *relhdr; Elf32_Word *symtab; Elf32_Word *symtab_shndx; @@ -617,12 +615,14 @@ static int do_func(Elf_Ehdr *const ehdr, char const *const fname, unsigned rel_entsize = 0; unsigned symsec_sh_link = 0; + struct section *sec; + int result = 0; if (find_section_by_name(lf, "__mcount_loc") != NULL) return 0; - totrelsz = tot_relsize(shdr0, nhdr, shstrtab, fname); + totrelsz = tot_relsize(shdr0, shstrtab, fname); if (totrelsz == 0) return 0; mrel0 = umalloc(totrelsz); @@ -640,15 +640,18 @@ static int do_func(Elf_Ehdr *const ehdr, char const *const fname, find_symtab(ehdr, shdr0, nhdr, &symtab, &symtab_shndx); - for (relhdr = shdr0, k = nhdr; k; --k, ++relhdr) { - char const *const txtname = has_rel_mcount(relhdr, shdr0, + list_for_each_entry(sec, &lf->sections, list) { + char const *txtname; + + relhdr = &sec->sh; + txtname = has_rel_mcount(relhdr, shdr0, shstrtab, fname); if (txtname && is_mcounted_section_name(txtname)) { unsigned int recsym; uint_t recval = 0; - symsec_sh_link = w(relhdr->sh_link); - result = find_secsym_ndx(w(relhdr->sh_info), txtname, + symsec_sh_link = relhdr->sh_link; + result = find_secsym_ndx(relhdr->sh_info, txtname, &recval, &recsym, &shdr0[symsec_sh_link], symtab, symtab_shndx, @@ -656,7 +659,7 @@ static int do_func(Elf_Ehdr *const ehdr, char const *const fname, if (result) goto out; - rel_entsize = _w(relhdr->sh_entsize); + rel_entsize = relhdr->sh_entsize; mlocp = sift_rel_mcount(mlocp, (void *)mlocp - (void *)mloc0, &mrelp, relhdr, ehdr, recsym, recval, reltype); -- 2.20.1