From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga06-in.huawei.com (szxga06-in.huawei.com [45.249.212.32]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E626D4C92; Sat, 14 Sep 2024 02:53:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.32 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726282389; cv=none; b=BU+asmbGYTGkP9tPEQ3NFG/uTLwIOkRW2pNQV3WYScDCovFD6aQk18vSDSwATn+RQ/sxfHQGfMNmw/eU7FR7XtUOvB7Zzy4Vb7VLTNICEypHmnOHD69duTd7y5jUe55mBurqlagG9QZGVRnIjZVS2klf5JwdsSHQlKAh5GD8miU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726282389; c=relaxed/simple; bh=CzdkWVv9/yiMtGtG4wA7P6VDMMTifj0mpX3iXE4TtcU=; h=Message-ID:Date:MIME-Version:Subject:From:To:CC:References: In-Reply-To:Content-Type; b=sAosRz5Wnqa1LOb3NSXPuC/7ke7FXlEgYmSqAe+iuG3kmziARu34wPjc9sx4A38/vjmqcQ5hwQMQPeAUqCULOqoIHLgPJd3c2cO2ibw6uOB6EfEFis+PX7Fvw44AUcH0Z/M7Z4BqTWikhNVN/W6Pbq4wCzi9i6gWLbdx7aDsr9w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.32 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.88.234]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4X5G262rV7z23jX3; Sat, 14 Sep 2024 10:53:02 +0800 (CST) Received: from kwepemd200013.china.huawei.com (unknown [7.221.188.133]) by mail.maildlp.com (Postfix) with ESMTPS id 1523A140134; Sat, 14 Sep 2024 10:53:03 +0800 (CST) Received: from [10.67.110.108] (10.67.110.108) by kwepemd200013.china.huawei.com (7.221.188.133) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.34; Sat, 14 Sep 2024 10:53:02 +0800 Message-ID: Date: Sat, 14 Sep 2024 10:53:01 +0800 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.11.2 Subject: Re: [PATCH v3 0/2] uprobes: Improve scalability by reducing the contention on siglock From: "Liao, Chang" To: CC: , , , , Masami Hiramatsu , Peter Zijlstra , Andrii Nakryiko References: <20240815014629.2685155-1-liaochang1@huawei.com> In-Reply-To: <20240815014629.2685155-1-liaochang1@huawei.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To kwepemd200013.china.huawei.com (7.221.188.133) Hi, Oleg Kindly ping. This series have been pending for a month. Is thre any issue I overlook? Thanks. 在 2024/8/15 9:46, Liao Chang 写道: > The profiling result of BPF selftest on ARM64 platform reveals the > significant contention on the current->sighand->siglock is the > scalability bottleneck. The reason is also very straightforward that all > producer threads of benchmark have to contend the spinlock mentioned to > resume the TIF_SIGPENDING bit in thread_info that might be removed in > uprobe_deny_signal(). > > The contention on current->sighand->siglock is unnecessary, this series > remove them thoroughly. I've use the script developed by Andrii in [1] > to run benchmark. The CPU used was Kunpeng916 (Hi1616), 4 NUMA nodes, > 64 cores@2.4GHz running the kernel on next tree + the optimization in > [2] for get_xol_insn_slot(). > > before-opt > ---------- > uprobe-nop ( 1 cpus): 0.907 ± 0.003M/s ( 0.907M/s/cpu) > uprobe-nop ( 2 cpus): 1.676 ± 0.008M/s ( 0.838M/s/cpu) > uprobe-nop ( 4 cpus): 3.210 ± 0.003M/s ( 0.802M/s/cpu) > uprobe-nop ( 8 cpus): 4.457 ± 0.003M/s ( 0.557M/s/cpu) > uprobe-nop (16 cpus): 3.724 ± 0.011M/s ( 0.233M/s/cpu) > uprobe-nop (32 cpus): 2.761 ± 0.003M/s ( 0.086M/s/cpu) > uprobe-nop (64 cpus): 1.293 ± 0.015M/s ( 0.020M/s/cpu) > > uprobe-push ( 1 cpus): 0.883 ± 0.001M/s ( 0.883M/s/cpu) > uprobe-push ( 2 cpus): 1.642 ± 0.005M/s ( 0.821M/s/cpu) > uprobe-push ( 4 cpus): 3.086 ± 0.002M/s ( 0.771M/s/cpu) > uprobe-push ( 8 cpus): 3.390 ± 0.003M/s ( 0.424M/s/cpu) > uprobe-push (16 cpus): 2.652 ± 0.005M/s ( 0.166M/s/cpu) > uprobe-push (32 cpus): 2.713 ± 0.005M/s ( 0.085M/s/cpu) > uprobe-push (64 cpus): 1.313 ± 0.009M/s ( 0.021M/s/cpu) > > uprobe-ret ( 1 cpus): 1.774 ± 0.000M/s ( 1.774M/s/cpu) > uprobe-ret ( 2 cpus): 3.350 ± 0.001M/s ( 1.675M/s/cpu) > uprobe-ret ( 4 cpus): 6.604 ± 0.000M/s ( 1.651M/s/cpu) > uprobe-ret ( 8 cpus): 6.706 ± 0.005M/s ( 0.838M/s/cpu) > uprobe-ret (16 cpus): 5.231 ± 0.001M/s ( 0.327M/s/cpu) > uprobe-ret (32 cpus): 5.743 ± 0.003M/s ( 0.179M/s/cpu) > uprobe-ret (64 cpus): 4.726 ± 0.016M/s ( 0.074M/s/cpu) > > after-opt > --------- > uprobe-nop ( 1 cpus): 0.985 ± 0.002M/s ( 0.985M/s/cpu) > uprobe-nop ( 2 cpus): 1.773 ± 0.005M/s ( 0.887M/s/cpu) > uprobe-nop ( 4 cpus): 3.304 ± 0.001M/s ( 0.826M/s/cpu) > uprobe-nop ( 8 cpus): 5.328 ± 0.002M/s ( 0.666M/s/cpu) > uprobe-nop (16 cpus): 6.475 ± 0.002M/s ( 0.405M/s/cpu) > uprobe-nop (32 cpus): 4.831 ± 0.082M/s ( 0.151M/s/cpu) > uprobe-nop (64 cpus): 2.564 ± 0.053M/s ( 0.040M/s/cpu) > > uprobe-push ( 1 cpus): 0.964 ± 0.001M/s ( 0.964M/s/cpu) > uprobe-push ( 2 cpus): 1.766 ± 0.002M/s ( 0.883M/s/cpu) > uprobe-push ( 4 cpus): 3.290 ± 0.009M/s ( 0.823M/s/cpu) > uprobe-push ( 8 cpus): 4.670 ± 0.002M/s ( 0.584M/s/cpu) > uprobe-push (16 cpus): 5.197 ± 0.004M/s ( 0.325M/s/cpu) > uprobe-push (32 cpus): 5.068 ± 0.161M/s ( 0.158M/s/cpu) > uprobe-push (64 cpus): 2.605 ± 0.026M/s ( 0.041M/s/cpu) > > uprobe-ret ( 1 cpus): 1.833 ± 0.001M/s ( 1.833M/s/cpu) > uprobe-ret ( 2 cpus): 3.384 ± 0.003M/s ( 1.692M/s/cpu) > uprobe-ret ( 4 cpus): 6.677 ± 0.004M/s ( 1.669M/s/cpu) > uprobe-ret ( 8 cpus): 6.854 ± 0.005M/s ( 0.857M/s/cpu) > uprobe-ret (16 cpus): 6.508 ± 0.006M/s ( 0.407M/s/cpu) > uprobe-ret (32 cpus): 5.793 ± 0.009M/s ( 0.181M/s/cpu) > uprobe-ret (64 cpus): 4.743 ± 0.016M/s ( 0.074M/s/cpu) > > Above benchmark results demonstrates a obivious improvement in the > scalability of trig-uprobe-nop and trig-uprobe-push, the peak throughput > of which are from 4.5M/s to 6.4M/s and 3.3M/s to 5.1M/s individually. > > v3->v2: > Renaming the flag in [2/2], s/deny_signal/signal_denied/g. > > v2->v1: > Oleg pointed out the _DENY_SIGNAL will be replaced by _ACK upon the > completion of singlestep which leads to handle_singlestep() has no > chance to restore the removed TIF_SIGPENDING [3] and some case in > question. So this revision proposes to use a flag in uprobe_task to > track the denied TIF_SIGPENDING instead of new UPROBE_SSTEP state. > > [1] https://lore.kernel.org/all/20240731214256.3588718-1-andrii@kernel.org > [2] https://lore.kernel.org/all/20240727094405.1362496-1-liaochang1@huawei.com > [3] https://lore.kernel.org/all/20240801082407.1618451-1-liaochang1@huawei.com > > Liao Chang (2): > uprobes: Remove redundant spinlock in uprobe_deny_signal() > uprobes: Remove the spinlock within handle_singlestep() > > include/linux/uprobes.h | 1 + > kernel/events/uprobes.c | 10 +++++----- > 2 files changed, 6 insertions(+), 5 deletions(-) > -- BR Liao, Chang