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Wed, 8 Feb 2023 18:23:50 +0100 (CET) Message-ID: <20230208172245.430556498@infradead.org> User-Agent: quilt/0.66 Date: Wed, 08 Feb 2023 18:17:59 +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 03/10] objtool: Make instruction::alts a single-linked list 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" 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) --- */ unsigned int len; /* 64 4 */ enum insn_type type; /* 68 4 */ long unsigned int immediate; /* 72 8 */ u16 dead_end:1; /* 80: 0 2 */ u16 ignore:1; /* 80: 1 2 */ u16 ignore_alts:1; /* 80: 2 2 */ u16 hint:1; /* 80: 3 2 */ u16 save:1; /* 80: 4 2 */ u16 restore:1; /* 80: 5 2 */ u16 retpoline_safe:1; /* 80: 6 2 */ u16 noendbr:1; /* 80: 7 2 */ u16 entry:1; /* 80: 8 2 */ /* XXX 7 bits hole, try to pack */ s8 instr; /* 82 1 */ u8 visited; /* 83 1 */ /* XXX 4 bytes hole, try to pack */ struct alt_group * alt_group; /* 88 8 */ struct symbol * call_dest; /* 96 8 */ struct instruction * jump_dest; /* 104 8 */ struct instruction * first_jump_src; /* 112 8 */ struct reloc * jump_table; /* 120 8 */ /* --- cacheline 2 boundary (128 bytes) --- */ struct reloc * reloc; /* 128 8 */ - struct list_head alts; /* 136 16 */ - struct symbol * sym; /* 152 8 */ - struct stack_op * stack_ops; /* 160 8 */ - struct cfi_state * cfi; /* 168 8 */ + struct alternative * alts; /* 136 8 */ + struct symbol * sym; /* 144 8 */ + struct stack_op * stack_ops; /* 152 8 */ + struct cfi_state * cfi; /* 160 8 */ - /* size: 176, cachelines: 3, members: 29 */ - /* sum members: 170, holes: 1, sum holes: 4 */ + /* size: 168, cachelines: 3, members: 29 */ + /* sum members: 162, holes: 1, sum holes: 4 */ /* sum bitfield members: 9 bits, bit holes: 1, sum bit holes: 7 bits */ - /* last cacheline: 48 bytes */ + /* last cacheline: 40 bytes */ }; pre: 5:58.50 real, 229.64 user, 128.65 sys, 26221520 mem post: 5:48.86 real, 220.30 user, 128.34 sys, 24834672 mem Signed-off-by: Peter Zijlstra (Intel) --- tools/objtool/check.c | 18 +++++++++--------- tools/objtool/include/objtool/check.h | 2 +- 2 files changed, 10 insertions(+), 10 deletions(-) --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -23,7 +23,7 @@ #include =20 struct alternative { - struct list_head list; + struct alternative *next; struct instruction *insn; bool skip_orig; }; @@ -395,7 +395,6 @@ static int decode_instructions(struct ob return -1; } memset(insn, 0, sizeof(*insn)); - INIT_LIST_HEAD(&insn->alts); INIT_LIST_HEAD(&insn->call_node); =20 insn->sec =3D sec; @@ -1768,7 +1767,6 @@ static int handle_group_alt(struct objto return -1; } memset(nop, 0, sizeof(*nop)); - INIT_LIST_HEAD(&nop->alts); =20 nop->sec =3D special_alt->new_sec; nop->offset =3D special_alt->new_off + special_alt->new_len; @@ -1966,7 +1964,8 @@ static int add_special_section_alts(stru alt->insn =3D new_insn; alt->skip_orig =3D special_alt->skip_orig; orig_insn->ignore_alts |=3D special_alt->skip_alt; - list_add_tail(&alt->list, &orig_insn->alts); + alt->next =3D orig_insn->alts; + orig_insn->alts =3D alt; =20 list_del(&special_alt->list); free(special_alt); @@ -2025,7 +2024,8 @@ static int add_jump_table(struct objtool } =20 alt->insn =3D dest_insn; - list_add_tail(&alt->list, &insn->alts); + alt->next =3D insn->alts; + insn->alts =3D alt; prev_offset =3D reloc->offset; } =20 @@ -3576,10 +3576,10 @@ static int validate_branch(struct objtoo if (propagate_alt_cfi(file, insn)) return 1; =20 - if (!insn->ignore_alts && !list_empty(&insn->alts)) { + if (!insn->ignore_alts && insn->alts) { bool skip_orig =3D false; =20 - list_for_each_entry(alt, &insn->alts, list) { + for (alt =3D insn->alts; alt; alt =3D alt->next) { if (alt->skip_orig) skip_orig =3D true; =20 @@ -3778,11 +3778,11 @@ static int validate_entry(struct objtool =20 insn->visited |=3D VISITED_ENTRY; =20 - if (!insn->ignore_alts && !list_empty(&insn->alts)) { + if (!insn->ignore_alts && insn->alts) { struct alternative *alt; bool skip_orig =3D false; =20 - list_for_each_entry(alt, &insn->alts, list) { + for (alt =3D insn->alts; alt; alt =3D alt->next) { if (alt->skip_orig) skip_orig =3D true; =20 --- a/tools/objtool/include/objtool/check.h +++ b/tools/objtool/include/objtool/check.h @@ -66,7 +66,7 @@ struct instruction { struct instruction *first_jump_src; struct reloc *jump_table; struct reloc *reloc; - struct list_head alts; + struct alternative *alts; struct symbol *sym; struct stack_op *stack_ops; struct cfi_state *cfi;