From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 69-171-232-180.mail-mxout.facebook.com (69-171-232-180.mail-mxout.facebook.com [69.171.232.180]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7B27635A39D for ; Thu, 15 Oct 2026 04:02:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=69.171.232.180 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792036922; cv=none; b=k8ltJ2YaChDV6idf6nNWBm4KMYFT8347Je1q5uDtIfuwJA+5YbbJ47dFzy7kNYxHVQYsLu+HtRtEl7rlLfHHgpyY4s9J8AOXFQACVwrh+QeX9vxVxjGJ9vjxw1O8DnLDVnsZpKzkapvCh9I3EHJhZr/yQrjxQQTdEo47WjZN+ak= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792036922; c=relaxed/simple; bh=TmD/0EE0e7wiQqklwrWQiAOwU2Nlf7iWoeuDgcsl2pA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ilq5PdOmcQPlaIteM0q5DNxjVe34xeX44XRwDETm6r5KDNEqRXvK5oerU2tJSTL0VlKFRsRYNnUm/ftpbsEo5Al6salpPxKkdVNUtcxvQq5r3bFStNMJQ0VfW8pmBBPnokrDNNhG3qy5ADaXW/qBJu7xOidRgRcHcmNZIP+nwRk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.dev; spf=fail smtp.mailfrom=linux.dev; arc=none smtp.client-ip=69.171.232.180 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=linux.dev Received: by devvm16039.vll0.facebook.com (Postfix, from userid 128203) id E330931498BC72; Wed, 14 Oct 2026 21:01:48 -0700 (PDT) From: Yonghong Song To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , Eduard Zingerman , kernel-team@fb.com Subject: [PATCH bpf-next v11 01/26] bpf: Pack bpf_insn_aux_data flags into bit fields Date: Wed, 14 Oct 2026 21:01:48 -0700 Message-ID: <20261015040148.854746-1-yonghong.song@linux.dev> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261015040143.854070-1-yonghong.song@linux.dev> References: <20261015040143.854070-1-yonghong.song@linux.dev> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable struct bpf_insn_aux_data spreads its flags over eleven bools, a u8 of three bit fields and a u32 group with 25 of its 32 bits spare. Put them all in u64 bit fields, alu_state with them, which fit in the 32 bits beside seen, so orig_idx starts the next word. The structure goes from 216 bytes to 200, and stays there when a later patch adds a u32, which takes a hole further down. alu_state was a u8, but it only ever holds BPF_ALU_* flags, the highest of which is BPF_ALU_IMMEDIATE (1U << 4), so it gets five bits. With eight, the flags would take 34 bits, more than fit beside seen, so they would start a word of their own, and the later u32 would grow the structure to 208 bytes. A new BPF_ALU_* flag has to widen it. No functional change. Suggested-by: Eduard Zingerman Signed-off-by: Yonghong Song --- include/linux/bpf_verifier.h | 49 ++++++++++++++++++------------------ 1 file changed, 25 insertions(+), 24 deletions(-) diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index 791398e14962..112ca1511da4 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -767,44 +767,45 @@ struct bpf_insn_aux_data { u16 stack_ptrs; /* bitmask of regs that may hold a frame pointer here (= arg_track) */ int ctx_field_size; /* the ctx field size for load insn, maybe 0 */ u32 seen; /* this insn was processed by the verifier at env->pass_cnt *= / - bool nospec; /* do not execute this instruction speculatively */ - bool nospec_result; /* result is unsafe under speculation, nospec must = follow */ - bool zext_dst; /* this insn zero extends dst reg */ - bool needs_zext; /* alu op needs to clear upper bits */ - bool prevent_zext; /* alu op cannot be zext (already used with 64-bit s= calars) */ - bool non_sleepable; /* helper/kfunc may be called from non-sleepable co= ntext */ - bool is_iter_next; /* bpf_iter__next() kfunc call */ - bool call_with_percpu_alloc_ptr; /* {this,per}_cpu_ptr() with prog perc= pu alloc */ - bool arena_scalar; /* ldx/stx/st/atomic through a number, it's an addre= ss in arena */ - bool bb_end; /* last instruction of a basic block */ - bool need_scev; - u8 alu_state; /* used in combination with alu_limit */ + u64 nospec:1; /* do not execute this instruction speculatively */ + u64 nospec_result:1; /* result is unsafe under speculation, nospec must= follow */ + u64 zext_dst:1; /* this insn zero extends dst reg */ + u64 needs_zext:1; /* alu op needs to clear upper bits */ + u64 prevent_zext:1; /* alu op cannot be zext (already used with 64-bit = scalars) */ + u64 non_sleepable:1; /* helper/kfunc may be called from non-sleepable c= ontext */ + u64 is_iter_next:1; /* bpf_iter__next() kfunc call */ + u64 call_with_percpu_alloc_ptr:1; /* {this,per}_cpu_ptr() with prog per= cpu alloc */ + u64 arena_scalar:1; /* ldx/stx/st/atomic through a number, it's an addr= ess in arena */ + u64 bb_end:1; /* last instruction of a basic block */ + u64 need_scev:1; + u64 alu_state:5; /* used in combination with alu_limit */ /* true if STX or LDX instruction is a part of a spill/fill * pattern for a bpf_fastcall call. */ - u8 fastcall_pattern:1; + u64 fastcall_pattern:1; /* for CALL instructions, a number of spill/fill pairs in the * bpf_fastcall pattern. */ - u8 fastcall_spills_num:3; - u8 arg_prog:4; + u64 fastcall_spills_num:3; + u64 arg_prog:4; =20 - /* below fields are initialized once */ - unsigned int orig_idx; /* original instruction index */ - u32 jmp_point:1; - u32 prune_point:1; + /* below flags are initialized once */ + u64 jmp_point:1; + u64 prune_point:1; /* ensure we check state equivalence and save state checkpoint and * this instruction, regardless of any heuristics */ - u32 force_checkpoint:1; + u64 force_checkpoint:1; /* true if instruction is a call to a helper function that * accepts callback function as a parameter. */ - u32 calls_callback:1; - u32 indirect_target:1; /* if it is an indirect jump target */ - u32 non_stack_access:1; /* instruction can access non-stack memory */ + u64 calls_callback:1; + u64 indirect_target:1; /* if it is an indirect jump target */ + u64 non_stack_access:1; /* instruction can access non-stack memory */ /* true if some jump or call instruction targets this instruction */ - u32 jump_target:1; + u64 jump_target:1; + + unsigned int orig_idx; /* original instruction index, initialized once = */ /* * CFG strongly connected component this instruction belongs to, * zero if it is a singleton SCC. --=20 2.53.0-Meta