From nobody Mon Apr 27 13:48:16 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 97DDCC43334 for ; Mon, 13 Jun 2022 04:25:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231551AbiFMEZz (ORCPT ); Mon, 13 Jun 2022 00:25:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41942 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229638AbiFMEZn (ORCPT ); Mon, 13 Jun 2022 00:25:43 -0400 Received: from mail-pj1-x1032.google.com (mail-pj1-x1032.google.com [IPv6:2607:f8b0:4864:20::1032]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 18813CE8 for ; Sun, 12 Jun 2022 21:25:42 -0700 (PDT) Received: by mail-pj1-x1032.google.com with SMTP id e24so4607573pjt.0 for ; Sun, 12 Jun 2022 21:25:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=UJqqtLpsUI2pT8V/J8QM9a7rYqlcj52+1o8fnW9am6M=; b=He812w1u3b5Dd74KtEchC1TIzSGg5kClkXcShWEeGsfHAytYBzY5I+6AY7FqtUd6w/ y1mgEQiDAJVqsG+QpdRShDqonwebndEmRqiqbHw0SWXzmvKrnFVeKTvoU5Psmmvbk5+J f/gdnibNG1cPge9uJ40GWZCYtEqKkNdTwo3XXf9pBrKHpKn6fPKJzFc6NYUiTekBLn0j tEdiH+dbhZGDZWcBO6DS0Ad/rSoe/RCjVhDlYOPQUNo236u+7JlZdIe3SHp/WO/MXzzy /qNvKVlrKFLedFrUuwVs2ugwiKDRHPIbEo4DLvXj9HpP1w62ZCFJimj7l5+AV9N+gggS E+BA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=UJqqtLpsUI2pT8V/J8QM9a7rYqlcj52+1o8fnW9am6M=; b=jW3bd/ML+Hf2I4Xl/+Cq4pCM3x0vVWZeg56VE+WvnAbMFzyTFQ2wKBK/VX3gsdj2iJ Axl8tHeNWT0Jb6vvonsSuFiU85l6su56YQH5nt2E2KGKhp23ObmdLvssE/aVNLWnwwWO dZd+krvg5KpXN/TsXRErKy6u77Mh5lxteTW9nsetmOCFy4G/IzII0EWe8ZikHOeCQxu6 gu7WDFCz9n3dvZISEpxj4kAUbwLptoObRLxj2OrdtR2wkItlpNDC1Kq9Ls15qP6V6Cmt FbL7Olgzdl1QTst6FTTnbGEib+Nv/HFXh+Pkrpv+ck1h22+7QDib1m2XlWBiyHfurBDL 2cew== X-Gm-Message-State: AOAM530hSlyw0SpY8NZ84e3LXDX7ugxUdZY2Ca1f8fONudepJb3yS9z2 3u9yeCntSJhDV8CUKO4NFgI= X-Google-Smtp-Source: ABdhPJylwmTgv3qIMrAGkTiS9qCSUJUC8S7LvwQsbNxfneogBdy+AJDtg7D1yR1mGEIx+5udNY99oA== X-Received: by 2002:a17:90a:df14:b0:1e3:33ba:a94 with SMTP id gp20-20020a17090adf1400b001e333ba0a94mr13468317pjb.83.1655094341541; Sun, 12 Jun 2022 21:25:41 -0700 (PDT) Received: from localhost.localdomain (l3b2w1.cn. [159.138.1.25]) by smtp.gmail.com with ESMTPSA id bf10-20020a170902b90a00b001664ce47e11sm3848260plb.210.2022.06.12.21.25.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 12 Jun 2022 21:25:40 -0700 (PDT) From: l3b2w1@gmail.com To: mhiramat@kernel.org Cc: naveen.n.rao@linux.ibm.com, anil.s.keshavamurthy@intel.com, davem@davemloft.net, linux-kernel@vger.kernel.org, "binglei.wang" Subject: [PATCH] kprobes: drop the unnecessary unlikely() Date: Mon, 13 Jun 2022 12:25:36 +0800 Message-Id: <20220613042536.20329-1-l3b2w1@gmail.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: "binglei.wang" !ap is likely when checking re-registering existing kprobe. register_kprobe -> warn_kprobe_rereg -> __get_valid_kprobe !ap is unlikely when checking whether the kprobe is valid on enable/disable ocassion. __disable_kprobe/enable_kprobe -> __get_valid_kprobe Considering these two cases, choose to drop the unlikely() here. Signed-off-by: binglei.wang Acked-by: Masami Hiramatsu (Google) --- kernel/kprobes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index f214f8c08..f4a829d98 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1504,7 +1504,7 @@ static struct kprobe *__get_valid_kprobe(struct kprob= e *p) lockdep_assert_held(&kprobe_mutex); =20 ap =3D get_kprobe(p->addr); - if (unlikely(!ap)) + if (!ap) return NULL; =20 if (p !=3D ap) { --=20 2.27.0