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Wed, 8 Feb 2023 18:23:50 +0100 (CET) Message-ID: <20230208172245.572145269@infradead.org> User-Agent: quilt/0.66 Date: Wed, 08 Feb 2023 18:18:01 +0100 From: Peter Zijlstra To: x86@kernel.org, jpoimboe@redhat.com, linux@weissschuh.net Cc: linux-kernel@vger.kernel.org, peterz@infradead.org Subject: [PATCH 05/10] objtool: Remove instruction::reloc References: <20230208171756.898991570@infradead.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Instead of caching the reloc for each instruction, only keep a negative cache of not having a reloc (by far the most common case). struct instruction { struct list_head list; /* 0 16 */ struct hlist_node hash; /* 16 16 */ struct list_head call_node; /* 32 16 */ struct section * sec; /* 48 8 */ long unsigned int offset; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ long unsigned int immediate; /* 64 8 */ unsigned int len; /* 72 4 */ u8 type; /* 76 1 */ /* Bitfield combined with previous fields */ u16 dead_end:1; /* 76: 8 2 */ u16 ignore:1; /* 76: 9 2 */ u16 ignore_alts:1; /* 76:10 2 */ u16 hint:1; /* 76:11 2 */ u16 save:1; /* 76:12 2 */ u16 restore:1; /* 76:13 2 */ u16 retpoline_safe:1; /* 76:14 2 */ u16 noendbr:1; /* 76:15 2 */ u16 entry:1; /* 78: 0 2 */ u16 visited:4; /* 78: 1 2 */ + u16 no_reloc:1; /* 78: 5 2 */ - /* XXX 3 bits hole, try to pack */ + /* XXX 2 bits hole, try to pack */ /* Bitfield combined with next fields */ s8 instr; /* 79 1 */ struct alt_group * alt_group; /* 80 8 */ struct symbol * call_dest; /* 88 8 */ struct instruction * jump_dest; /* 96 8 */ struct instruction * first_jump_src; /* 104 8 */ struct reloc * jump_table; /* 112 8 */ - struct reloc * reloc; /* 120 8 */ + struct alternative * alts; /* 120 8 */ /* --- cacheline 2 boundary (128 bytes) --- */ - struct alternative * alts; /* 128 8 */ - struct symbol * sym; /* 136 8 */ - struct stack_op * stack_ops; /* 144 8 */ - struct cfi_state * cfi; /* 152 8 */ + struct symbol * sym; /* 128 8 */ + struct stack_op * stack_ops; /* 136 8 */ + struct cfi_state * cfi; /* 144 8 */ - /* size: 160, cachelines: 3, members: 29 */ - /* sum members: 158 */ - /* sum bitfield members: 13 bits, bit holes: 1, sum bit holes: 3 bits */ - /* last cacheline: 32 bytes */ + /* size: 152, cachelines: 3, members: 29 */ + /* sum members: 150 */ + /* sum bitfield members: 14 bits, bit holes: 1, sum bit holes: 2 bits */ + /* last cacheline: 24 bytes */ }; pre: 5:48.89 real, 220.96 user, 127.55 sys, 24834672 mem post: 5:39.35 real, 215.58 user, 123.69 sys, 23448736 mem Signed-off-by: Peter Zijlstra (Intel) --- tools/objtool/check.c | 26 ++++++++++++-------------- tools/objtool/include/objtool/check.h | 6 +++--- 2 files changed, 15 insertions(+), 17 deletions(-) --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1307,26 +1307,24 @@ __weak bool arch_is_rethunk(struct symbo return false; } =20 -#define NEGATIVE_RELOC ((void *)-1L) - static struct reloc *insn_reloc(struct objtool_file *file, struct instruct= ion *insn) { - if (insn->reloc =3D=3D NEGATIVE_RELOC) + struct reloc *reloc; + + if (insn->no_reloc) return NULL; =20 - if (!insn->reloc) { - if (!file) - return NULL; - - insn->reloc =3D find_reloc_by_dest_range(file->elf, insn->sec, - insn->offset, insn->len); - if (!insn->reloc) { - insn->reloc =3D NEGATIVE_RELOC; - return NULL; - } + if (!file) + return NULL; + + reloc =3D find_reloc_by_dest_range(file->elf, insn->sec, + insn->offset, insn->len); + if (!reloc) { + insn->no_reloc =3D 1; + return NULL; } =20 - return insn->reloc; + return reloc; } =20 static void remove_insn_ops(struct instruction *insn) --- a/tools/objtool/include/objtool/check.h +++ b/tools/objtool/include/objtool/check.h @@ -55,8 +55,9 @@ struct instruction { retpoline_safe : 1, noendbr : 1, entry : 1, - visited : 4; - /* 3 bit hole */ + visited : 4, + no_reloc : 1; + /* 2 bit hole */ =20 s8 instr; =20 @@ -65,7 +66,6 @@ struct instruction { struct instruction *jump_dest; struct instruction *first_jump_src; struct reloc *jump_table; - struct reloc *reloc; struct alternative *alts; struct symbol *sym; struct stack_op *stack_ops;