From patchwork Thu Dec 3 16:02:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brendan Jackman X-Patchwork-Id: 11949071 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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, 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,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 07983C2BBCF for ; Thu, 3 Dec 2020 16:05:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C316A207AE for ; Thu, 3 Dec 2020 16:05:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389302AbgLCQFJ (ORCPT ); Thu, 3 Dec 2020 11:05:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54924 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387680AbgLCQFI (ORCPT ); Thu, 3 Dec 2020 11:05:08 -0500 Received: from mail-qt1-x849.google.com (mail-qt1-x849.google.com [IPv6:2607:f8b0:4864:20::849]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4FC94C094242 for ; Thu, 3 Dec 2020 08:03:29 -0800 (PST) Received: by mail-qt1-x849.google.com with SMTP id l17so920243qtj.18 for ; Thu, 03 Dec 2020 08:03:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=Zq0SqodNfGWo0FrhKhUzqW6LznJPM9VRVrmmLrNNcbU=; b=TzpdEgvIUmgM+1bz8MY//NyO1rKyKk13IzzSbcbwV2VqrSdQS/3/qkAHCqh+yuY4/H BcYXGyH49FPaNcNTKp4BPzkuBgh3OzUnZmj0O8bPFCoFEiiq8L2BfXABRm2rsd1kD4kt vbq8FR7qTzYBIYz8iBUAqikcmhG+kWWeSnXtlK+t9TdwFVGtXJNpVRtUUIIFMRSxPvFG +13484oP8c//fOdSuOL88AArhx4eCcXDTFvWnEJxwid+Ni0Iml/emnmT1yP0EvWzLLWE AnCYrAKz1Tc0ivYwKfC4V3j/gPYh4K95FiJEvpMzEBqE4oS3ksGWnFpUa8m+2Uz34Si8 3UpQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=Zq0SqodNfGWo0FrhKhUzqW6LznJPM9VRVrmmLrNNcbU=; b=a5e94Mg4XwjV8FwnIwUZiB68FI7uXIChu42q3Iy5h3M0OWZ89htvpoBBrg8pQi4QFC oRi1Zt39+TOD4nn/e+nTIvEx2WAsqv61AjZirvfvkVFfjHM8eyzHk2rhFC5q2yuyLKWl +OZ3byi4TLH0NKkVQzzsFuw7DrX8Ct15HjwBbycbBCQPuwEMjHBRcd4WW52zCCMPEcfe UbyVIlmw19t06SjhF7dhiivwtsr7IFFGGFBWqDSAWWn5s1u+YCj/22pn6eXB/3JiB91j gxKBDJ8uqbMHUR4lGd12WCVzp2SFR9lUonlwjMv+K7R+hK00nfXaJOn2UK7r9rSHYstB 6DMg== X-Gm-Message-State: AOAM530e6W0MjYIlUtRFBAKiQTEwhxBtVC/GRYXgS8zc4xjANNZE8QG3 vIcjG8r9WkEqB2KfHh3auBKXdcz74FiWfOznX657+f7LJdgVxhYWpS2xqa/XvLPPgjMJy9Lfye3 ddBH37PcEz3Z5ntLRU1LMl8VAHmB/2MMhh/v06hJVrArna3jvCeBdtk/DssHPStc= X-Google-Smtp-Source: ABdhPJwkdXHQOyAMC7vF09gVHjOmwUzAc8dqhl2UErBbxOARkbN+aoGdeq08jVpteVp0sZU0pzV+ymxRatUYsg== Sender: "jackmanb via sendgmr" X-Received: from beeg.c.googlers.com ([fda3:e722:ac3:cc00:28:9cb1:c0a8:11db]) (user=jackmanb job=sendgmr) by 2002:a0c:ec4a:: with SMTP id n10mr3763187qvq.54.1607011408407; Thu, 03 Dec 2020 08:03:28 -0800 (PST) Date: Thu, 3 Dec 2020 16:02:40 +0000 In-Reply-To: <20201203160245.1014867-1-jackmanb@google.com> Message-Id: <20201203160245.1014867-10-jackmanb@google.com> Mime-Version: 1.0 References: <20201203160245.1014867-1-jackmanb@google.com> X-Mailer: git-send-email 2.29.2.454.gaff20da3a2-goog Subject: [PATCH bpf-next v3 09/14] bpf: Pull out a macro for interpreting atomic ALU operations From: Brendan Jackman To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Yonghong Song , Daniel Borkmann , KP Singh , Florent Revest , linux-kernel@vger.kernel.org, Jann Horn , Brendan Jackman Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Since the atomic operations that are added in subsequent commits are all isomorphic with BPF_ADD, pull out a macro to avoid the interpreter becoming dominated by lines of atomic-related code. Note that this sacrificies interpreter performance (combining STX_ATOMIC_W and STX_ATOMIC_DW into single switch case means that we need an extra conditional branch to differentiate them) in favour of compact and (relatively!) simple C code. Change-Id: I8cae5b66e75f34393de6063b91c05a8006fdd9e6 Signed-off-by: Brendan Jackman Acked-by: Yonghong Song --- kernel/bpf/core.c | 79 +++++++++++++++++++++++------------------------ 1 file changed, 38 insertions(+), 41 deletions(-) diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 28f960bc2e30..498d3f067be7 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -1618,55 +1618,52 @@ static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u64 *stack) LDX_PROBE(DW, 8) #undef LDX_PROBE - STX_ATOMIC_W: - switch (IMM) { - case BPF_ADD: - /* lock xadd *(u32 *)(dst_reg + off16) += src_reg */ - atomic_add((u32) SRC, (atomic_t *)(unsigned long) - (DST + insn->off)); - break; - case BPF_ADD | BPF_FETCH: - SRC = (u32) atomic_fetch_add( - (u32) SRC, - (atomic_t *)(unsigned long) (DST + insn->off)); - break; - case BPF_XCHG: - SRC = (u32) atomic_xchg( - (atomic_t *)(unsigned long) (DST + insn->off), - (u32) SRC); - break; - case BPF_CMPXCHG: - BPF_R0 = (u32) atomic_cmpxchg( - (atomic_t *)(unsigned long) (DST + insn->off), - (u32) BPF_R0, (u32) SRC); +#define ATOMIC(BOP, KOP) \ + case BOP: \ + if (BPF_SIZE(insn->code) == BPF_W) \ + atomic_##KOP((u32) SRC, (atomic_t *)(unsigned long) \ + (DST + insn->off)); \ + else \ + atomic64_##KOP((u64) SRC, (atomic64_t *)(unsigned long) \ + (DST + insn->off)); \ + break; \ + case BOP | BPF_FETCH: \ + if (BPF_SIZE(insn->code) == BPF_W) \ + SRC = (u32) atomic_fetch_##KOP( \ + (u32) SRC, \ + (atomic_t *)(unsigned long) (DST + insn->off)); \ + else \ + SRC = (u64) atomic64_fetch_##KOP( \ + (u64) SRC, \ + (atomic64_t *)(s64) (DST + insn->off)); \ break; - default: - goto default_label; - } - CONT; STX_ATOMIC_DW: + STX_ATOMIC_W: switch (IMM) { - case BPF_ADD: - /* lock xadd *(u64 *)(dst_reg + off16) += src_reg */ - atomic64_add((u64) SRC, (atomic64_t *)(unsigned long) - (DST + insn->off)); - break; - case BPF_ADD | BPF_FETCH: - SRC = (u64) atomic64_fetch_add( - (u64) SRC, - (atomic64_t *)(s64) (DST + insn->off)); - break; + ATOMIC(BPF_ADD, add) + case BPF_XCHG: - SRC = (u64) atomic64_xchg( - (atomic64_t *)(u64) (DST + insn->off), - (u64) SRC); + if (BPF_SIZE(insn->code) == BPF_W) + SRC = (u32) atomic_xchg( + (atomic_t *)(unsigned long) (DST + insn->off), + (u32) SRC); + else + SRC = (u64) atomic64_xchg( + (atomic64_t *)(u64) (DST + insn->off), + (u64) SRC); break; case BPF_CMPXCHG: - BPF_R0 = (u64) atomic64_cmpxchg( - (atomic64_t *)(u64) (DST + insn->off), - (u64) BPF_R0, (u64) SRC); + if (BPF_SIZE(insn->code) == BPF_W) + BPF_R0 = (u32) atomic_cmpxchg( + (atomic_t *)(unsigned long) (DST + insn->off), + (u32) BPF_R0, (u32) SRC); + else + BPF_R0 = (u64) atomic64_cmpxchg( + (atomic64_t *)(u64) (DST + insn->off), + (u64) BPF_R0, (u64) SRC); break; + default: goto default_label; }