From patchwork Wed Jun 16 13:34:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 12325223 X-Patchwork-Delegate: bpf@iogearbox.net 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=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 25741C48BE5 for ; Wed, 16 Jun 2021 13:34:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0820C61375 for ; Wed, 16 Jun 2021 13:34:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232731AbhFPNgK (ORCPT ); Wed, 16 Jun 2021 09:36:10 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:20227 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232628AbhFPNgK (ORCPT ); Wed, 16 Jun 2021 09:36:10 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1623850444; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=wYyH6y3KnqWy8HsjlCX5FvTHwB0hvgiy3z6sOMMrSuk=; b=SGLDK7S6qNS0go5hV12XJ2iNTaEovytHoF69oRU3+vCrq8SSp1fmNmbEcf2iejOXFLy5QB 45thVcnueXPp8jIZF0//UW0jP6okY2+CZmSTtR3CkFsIlEEwkoqgn9u1C36EcdxopJ6B5t L1pcoHeVnmbpcWmlSvOiU8se2j9C6Og= Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-493-1thtcSo1OzC0XfflExue1g-1; Wed, 16 Jun 2021 09:34:03 -0400 X-MC-Unique: 1thtcSo1OzC0XfflExue1g-1 Received: by mail-ed1-f70.google.com with SMTP id h23-20020aa7c5d70000b029038fed7b27d5so1017139eds.21 for ; Wed, 16 Jun 2021 06:34:02 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=wYyH6y3KnqWy8HsjlCX5FvTHwB0hvgiy3z6sOMMrSuk=; b=IrRU2mK0X2G4zK6ClYfHWFiUqiaEA48C7jK/uBZRUPNxnA1R4hZGCloXtFoOHOdmw8 Vb/rWQvhZkHtV6FE0YA5mxQsN4Zx0Q7DtWRc1uefck/2zmHsXFGHcdABiZRItBHYoz3M dovDRX3DdPnKAIS3wDPa4PATvGA1UE4NFuhtyOJkwjz7O7nnt6nyUzw1fReQpwIMYtCn u6qckAdwE4FSnx+AJoPuApd5XpfIfkKMOPAj4wZqX/ANeAGq8hcUwMnxYPP28I3K4dgm c2XTnLSxaZ1IP/rwKJ1vAnJ+is7vpAQjiU3UFAlUTp63g5jOiJE0N2gf/HGr/grwqIAY fJvQ== X-Gm-Message-State: AOAM533V32UGOcayEihz12pDK+r6BnG3eBajYRH6ca2XvPap/XgHdAdd fxq17k4IO8C8Q7rBCtttjxam21JIDPmlSsElq6LkkaiPivo7rEyls0AkojCakoCysGOI4Q8TrHE NXfZEhbNmXNVi X-Received: by 2002:a17:907:a92:: with SMTP id by18mr4345755ejc.224.1623850441768; Wed, 16 Jun 2021 06:34:01 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwc0/WxYw/13W0Y0GulydwIxjlhxiJAunvQdxDz6j35EB0j1sYj2wudpMU/saeifprv2DTjAA== X-Received: by 2002:a17:907:a92:: with SMTP id by18mr4345741ejc.224.1623850441610; Wed, 16 Jun 2021 06:34:01 -0700 (PDT) Received: from krava.redhat.com ([83.240.60.126]) by smtp.gmail.com with ESMTPSA id d24sm1861909edr.95.2021.06.16.06.34.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Jun 2021 06:34:01 -0700 (PDT) From: Jiri Olsa X-Google-Original-From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh Subject: [PATCH bpf-next] bpf, x86: Remove unused cnt increase from EMIT macro Date: Wed, 16 Jun 2021 15:34:00 +0200 Message-Id: <20210616133400.315039-1-jolsa@kernel.org> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Removing unused cnt increase from EMIT macro together with cnt declarations. This was introduced in commit [1] to ensure proper code generation. But that code was removed in commit [2] and this extra code was left in. [1] b52f00e6a715 ("x86: bpf_jit: implement bpf_tail_call() helper") [2] ebf7d1f508a7 ("bpf, x64: rework pro/epilogue and tailcall handling in JIT") Signed-off-by: Jiri Olsa --- arch/x86/net/bpf_jit_comp.c | 39 ++++++++++--------------------------- 1 file changed, 10 insertions(+), 29 deletions(-) diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 2a2e290fa5d8..19715542cd9c 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -31,7 +31,7 @@ static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len) } #define EMIT(bytes, len) \ - do { prog = emit_code(prog, bytes, len); cnt += len; } while (0) + do { prog = emit_code(prog, bytes, len); } while (0) #define EMIT1(b1) EMIT(b1, 1) #define EMIT2(b1, b2) EMIT((b1) + ((b2) << 8), 2) @@ -239,7 +239,6 @@ struct jit_context { static void push_callee_regs(u8 **pprog, bool *callee_regs_used) { u8 *prog = *pprog; - int cnt = 0; if (callee_regs_used[0]) EMIT1(0x53); /* push rbx */ @@ -255,7 +254,6 @@ static void push_callee_regs(u8 **pprog, bool *callee_regs_used) static void pop_callee_regs(u8 **pprog, bool *callee_regs_used) { u8 *prog = *pprog; - int cnt = 0; if (callee_regs_used[3]) EMIT2(0x41, 0x5F); /* pop r15 */ @@ -303,7 +301,6 @@ static void emit_prologue(u8 **pprog, u32 stack_depth, bool ebpf_from_cbpf, static int emit_patch(u8 **pprog, void *func, void *ip, u8 opcode) { u8 *prog = *pprog; - int cnt = 0; s64 offset; offset = func - (ip + X86_PATCH_SIZE); @@ -423,7 +420,6 @@ static void emit_bpf_tail_call_indirect(u8 **pprog, bool *callee_regs_used, int off1 = 42; int off2 = 31; int off3 = 9; - int cnt = 0; /* count the additional bytes used for popping callee regs from stack * that need to be taken into account for each of the offsets that @@ -513,7 +509,6 @@ static void emit_bpf_tail_call_direct(struct bpf_jit_poke_descriptor *poke, int pop_bytes = 0; int off1 = 20; int poke_off; - int cnt = 0; /* count the additional bytes used for popping callee regs to stack * that need to be taken into account for jump offset that is used for @@ -615,7 +610,6 @@ static void emit_mov_imm32(u8 **pprog, bool sign_propagate, { u8 *prog = *pprog; u8 b1, b2, b3; - int cnt = 0; /* * Optimization: if imm32 is positive, use 'mov %eax, imm32' @@ -655,7 +649,6 @@ static void emit_mov_imm64(u8 **pprog, u32 dst_reg, const u32 imm32_hi, const u32 imm32_lo) { u8 *prog = *pprog; - int cnt = 0; if (is_uimm32(((u64)imm32_hi << 32) | (u32)imm32_lo)) { /* @@ -678,7 +671,6 @@ static void emit_mov_imm64(u8 **pprog, u32 dst_reg, static void emit_mov_reg(u8 **pprog, bool is64, u32 dst_reg, u32 src_reg) { u8 *prog = *pprog; - int cnt = 0; if (is64) { /* mov dst, src */ @@ -697,7 +689,6 @@ static void emit_mov_reg(u8 **pprog, bool is64, u32 dst_reg, u32 src_reg) static void emit_insn_suffix(u8 **pprog, u32 ptr_reg, u32 val_reg, int off) { u8 *prog = *pprog; - int cnt = 0; if (is_imm8(off)) { /* 1-byte signed displacement. @@ -720,7 +711,6 @@ static void emit_insn_suffix(u8 **pprog, u32 ptr_reg, u32 val_reg, int off) static void maybe_emit_mod(u8 **pprog, u32 dst_reg, u32 src_reg, bool is64) { u8 *prog = *pprog; - int cnt = 0; if (is64) EMIT1(add_2mod(0x48, dst_reg, src_reg)); @@ -733,7 +723,6 @@ static void maybe_emit_mod(u8 **pprog, u32 dst_reg, u32 src_reg, bool is64) static void emit_ldx(u8 **pprog, u32 size, u32 dst_reg, u32 src_reg, int off) { u8 *prog = *pprog; - int cnt = 0; switch (size) { case BPF_B: @@ -764,7 +753,6 @@ static void emit_ldx(u8 **pprog, u32 size, u32 dst_reg, u32 src_reg, int off) static void emit_stx(u8 **pprog, u32 size, u32 dst_reg, u32 src_reg, int off) { u8 *prog = *pprog; - int cnt = 0; switch (size) { case BPF_B: @@ -799,7 +787,6 @@ static int emit_atomic(u8 **pprog, u8 atomic_op, u32 dst_reg, u32 src_reg, s16 off, u8 bpf_size) { u8 *prog = *pprog; - int cnt = 0; EMIT1(0xF0); /* lock prefix */ @@ -869,10 +856,10 @@ static void detect_reg_usage(struct bpf_insn *insn, int insn_cnt, } } -static int emit_nops(u8 **pprog, int len) +static void emit_nops(u8 **pprog, int len) { u8 *prog = *pprog; - int i, noplen, cnt = 0; + int i, noplen; while (len > 0) { noplen = len; @@ -886,8 +873,6 @@ static int emit_nops(u8 **pprog, int len) } *pprog = prog; - - return cnt; } #define INSN_SZ_DIFF (((addrs[i] - addrs[i - 1]) - (prog - temp))) @@ -902,7 +887,7 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, bool tail_call_seen = false; bool seen_exit = false; u8 temp[BPF_MAX_INSN_SIZE + BPF_INSN_SAFETY]; - int i, cnt = 0, excnt = 0; + int i, excnt = 0; int ilen, proglen = 0; u8 *prog = temp; int err; @@ -1576,7 +1561,7 @@ st: if (is_imm8(insn->off)) nops); return -EFAULT; } - cnt += emit_nops(&prog, nops); + emit_nops(&prog, nops); } EMIT2(jmp_cond, jmp_offset); } else if (is_simm32(jmp_offset)) { @@ -1622,7 +1607,7 @@ st: if (is_imm8(insn->off)) nops); return -EFAULT; } - cnt += emit_nops(&prog, nops); + emit_nops(&prog, nops); } break; } @@ -1647,7 +1632,7 @@ st: if (is_imm8(insn->off)) nops); return -EFAULT; } - cnt += emit_nops(&prog, INSN_SZ_DIFF - 2); + emit_nops(&prog, INSN_SZ_DIFF - 2); } EMIT2(0xEB, jmp_offset); } else if (is_simm32(jmp_offset)) { @@ -1754,7 +1739,6 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog, { u8 *prog = *pprog; u8 *jmp_insn; - int cnt = 0; /* arg1: mov rdi, progs[i] */ emit_mov_imm64(&prog, BPF_REG_1, (long) p >> 32, (u32) (long) p); @@ -1822,7 +1806,6 @@ static void emit_align(u8 **pprog, u32 align) static int emit_cond_near_jump(u8 **pprog, void *func, void *ip, u8 jmp_cond) { u8 *prog = *pprog; - int cnt = 0; s64 offset; offset = func - (ip + 2 + 4); @@ -1854,7 +1837,7 @@ static int invoke_bpf_mod_ret(const struct btf_func_model *m, u8 **pprog, u8 **branches) { u8 *prog = *pprog; - int i, cnt = 0; + int i; /* The first fmod_ret program will receive a garbage return value. * Set this to 0 to avoid confusing the program. @@ -1950,7 +1933,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i struct bpf_tramp_progs *tprogs, void *orig_call) { - int ret, i, cnt = 0, nr_args = m->nr_args; + int ret, i, nr_args = m->nr_args; int stack_size = nr_args * 8; struct bpf_tramp_progs *fentry = &tprogs[BPF_TRAMP_FENTRY]; struct bpf_tramp_progs *fexit = &tprogs[BPF_TRAMP_FEXIT]; @@ -2095,8 +2078,6 @@ static int emit_fallback_jump(u8 **pprog) */ err = emit_jump(&prog, __x86_indirect_thunk_rdx, prog); #else - int cnt = 0; - EMIT2(0xFF, 0xE2); /* jmp rdx */ #endif *pprog = prog; @@ -2106,7 +2087,7 @@ static int emit_fallback_jump(u8 **pprog) static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs) { u8 *jg_reloc, *prog = *pprog; - int pivot, err, jg_bytes = 1, cnt = 0; + int pivot, err, jg_bytes = 1; s64 jg_offset; if (a == b) {