From mboxrd@z Thu Jan 1 00:00:00 1970 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 55BB5FA373E for ; Tue, 25 Oct 2022 10:09:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229782AbiJYKJf (ORCPT ); Tue, 25 Oct 2022 06:09:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32916 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232310AbiJYKI7 (ORCPT ); Tue, 25 Oct 2022 06:08:59 -0400 Received: from mail-vk1-xa35.google.com (mail-vk1-xa35.google.com [IPv6:2607:f8b0:4864:20::a35]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B7FCAD0CD6 for ; Tue, 25 Oct 2022 03:02:27 -0700 (PDT) Received: by mail-vk1-xa35.google.com with SMTP id m18so2776365vka.10 for ; Tue, 25 Oct 2022 03:02:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=xjcOdBz7+1s+SY2r8uPJdaB5l1xd98vivegT7WmsGzE=; b=uSml8+DnXdwQjFDu/31djurwZibknnkEBl0HfloAE435L9yijx8dYxLlvQivqhXScV h8hsofYyvULgKM+IrK5ydVpNk2DVBZWOvfe0dOoj5bpPFzmbV3vepj7d5Qt8wwhS1Zzo 1W0glP4SH09ohTe+ZpDakMXVCo6TxCdx2q0M2gRDgTsJ08FXfEBJ1wpZf9V+uvwO6x2W lToztvWSBjLfQRKeQr+2+UEJI6Kb6NDH8nxwTJw5mTjDd/iG6tavzkeL7Ufw28RgKYdI f+MJmcCnHhl64lktXOa2tRzpI8O7seGSWpp3P+RnB0+dPQzUzfmeoO3nn0hgPpScNt05 9pxA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=xjcOdBz7+1s+SY2r8uPJdaB5l1xd98vivegT7WmsGzE=; b=7qzJ+CipRE2Etgy4vnedEh4b/elLgkPnQ+CzRdcyB2yD8k1aMiMkAJFM4EGYOkQgvY k11LK0rqiEGmF6ZS/IlVp4TL2wBulOySm3mlau19NSb5TgJJlaO5M5HPVZWa65vKNkpQ Tx7niR9WIH6dzK+isMAtsISqRLFBraRT9xQGC5mqMR3/neIay1SNXq2t3knV09mKmS4/ AGrnzY6wLPpygyYaoOcAgfF9tbKXdbwYOMWC/4/v31y0TK0y/sT+0qEJyDgx1bglT0K1 q1RHCIF0pu74XMRxXaiwQzk5PyESH3ZuQqALT3+kdpDfPYLZrytj/pCF32MGmHf06h7B mUqw== X-Gm-Message-State: ACrzQf3nxH48Hk4ZIVcVl4bZZX0arCJI738/0cPWHn0ciSNfbnVEf9PN yXAI7vtLpf+VI8Ct7XeRAvNd/TEt4UqB7g== X-Google-Smtp-Source: AMsMyM5lGX2enYqCifLrbJt/SBNBsI/Lsd2ohDjqOo4h1cts463R0iTdtrUa1OmGWVr2s3/wWMQApg== X-Received: by 2002:a17:902:ec83:b0:17c:afb3:d1ec with SMTP id x3-20020a170902ec8300b0017cafb3d1ecmr37607960plg.172.1666692135945; Tue, 25 Oct 2022 03:02:15 -0700 (PDT) Received: from devtp.bytedance.net ([139.177.225.227]) by smtp.gmail.com with ESMTPSA id p13-20020a170902e74d00b0017a018221e2sm962387plf.70.2022.10.25.03.02.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Oct 2022 03:02:15 -0700 (PDT) From: wuqiang To: mhiramat@kernel.org, davem@davemloft.net, anil.s.keshavamurthy@intel.com, naveen.n.rao@linux.ibm.com Cc: linux-kernel@vger.kernel.org, mattwu@163.com, wuqiang Subject: [PATCH] kretprobe events missing on 2-core KVM guest Date: Tue, 25 Oct 2022 18:01:17 +0800 Message-Id: <20221025100117.18667-1-wuqiang.matt@bytedance.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Default value of maxactive is set as num_possible_cpus() for nonpreemptable systems. For a 2-core system, only 2 kretprobe instances would be allocated in default, then these 2 instances for execve kretprobe are very likely to be used up with a pipelined command. This patch increases the minimum of maxactive to 10. Signed-off-by: wuqiang --- kernel/kprobes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 3220b0a2fb4a..b781dee3f552 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2211,7 +2211,7 @@ int register_kretprobe(struct kretprobe *rp) #ifdef CONFIG_PREEMPTION rp->maxactive = max_t(unsigned int, 10, 2*num_possible_cpus()); #else - rp->maxactive = num_possible_cpus(); + rp->maxactive = max_t(unsigned int, 10, num_possible_cpus()); #endif } #ifdef CONFIG_KRETPROBE_ON_RETHOOK -- 2.34.1