From patchwork Sun Feb 16 08:41:09 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yongliang Gao X-Patchwork-Id: 13976363 Received: from mail-pl1-f182.google.com (mail-pl1-f182.google.com [209.85.214.182]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 55B43156F54; Sun, 16 Feb 2025 08:42:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.182 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739695321; cv=none; b=eAx2JIvEebx1gOxcKpS8b97DxhlkYuAQFfKy1CgaGDVCb9V2wqYa8wfmBJlWU8tSdSRS/CwnScvw7b5NgX03HeCk9E7S9M7Ok/HkZTguwngc6s/hXSjTms8k9N0DpSwA0WAVxu33zSceXEl44WaP3rV8ogqjNY/xbnk560Mq4dI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739695321; c=relaxed/simple; bh=Vskc2wwVqA5Ms7gkLQLcg3MEV8RCfdMgVZ3QWgJZO90=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=D6fQNz7cIc1mcModLLxn6yFBbCP0dmrFe+1Owiarp6VwQp3F7eBPKd+GZsB8sxvECt5IkbaUQBFZVItK5h/MXMZJirCsi9xz1HpRpxQmBkcy3gT72LXeG4N1eco2gecyfAiGVyXpb8ETHp4+MHQIAd3dsztrm6cq5Cvo8czTRJY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=P4TwHDBp; arc=none smtp.client-ip=209.85.214.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="P4TwHDBp" Received: by mail-pl1-f182.google.com with SMTP id d9443c01a7336-220d39a5627so49610245ad.1; Sun, 16 Feb 2025 00:42:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1739695320; x=1740300120; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=/Uo8I2VTpZsm/M0eSKbaSlNCrIf12xCPXDdrqy9nBvo=; b=P4TwHDBpeh6M7610/9FzvPiOeoeLOR3PgXmVV1tPALgZrMvLancGcIp8hPyVB/o29W uDc/nngDkJX7EDbYMiIRyCf4WVg29QaqLDprmD4IA3OOfFE8FO4Y7F7jB30hSM50D+hp OiBGNLhC1TtSEvVyUGuyPwdt9TqF/lw6riG6Wzh5BdkgYuOyQjRyBxWUJ/+tZqPrQJa1 CJOutdmi7uMHQmSi3L8DdtJcVWDWTfH5kY/iB+YkjfdPkEIoORlhagWlVLhAMcnz+nAa GTEek2t06T8xKWrk0X9OSIOjwbuOz3rkAPwnVIQ9wzIJzStFiwkOF9dGl8g0Eg8YrZ/L gLnw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1739695320; x=1740300120; 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=/Uo8I2VTpZsm/M0eSKbaSlNCrIf12xCPXDdrqy9nBvo=; b=Poxe4B31jRopDecnkIQkqljbPC1DMsCrfahT2T/VfflBwwvjFWwB7lptq0Y/4R9qvD oN+eJ3jVN/B5RikuVdO/u7lcBZZn7dNAMdAJWOsJkb0wqce1fnQQMnOxzk6FJVqg6K6s 5ASBbkDgxrXYycL3u5xUGJVg4VSGATYwWW436thqQQHXLnbYYgc/T5+FeYzKkOI3XmZt IxxN8FmSzOAlx1iKEeexJFHlAdc53lKpgJB+t/2YHd7I5vKL8iTD2K+F55E4RZKJMI69 XUpUvp0wycf+IE/XgIQsZ5lYBvVFIJjCp34dKpysPAVbPjYbjE7nYwxxu+4fl+qmXNqK 7SVw== X-Forwarded-Encrypted: i=1; AJvYcCVizOdCUhDK68JpDKOzK7e8b7jMOAGONhmR6BQFIwM4qrUPkqpPheDICWWkrQ+6TG4FBORt@vger.kernel.org, AJvYcCWVA8+rKcnz7MzHukU6et8B3aZlSWM/hwqWB3Cm+2MhbG0u2gxy7AYUMrXmIGkpstgOLvxkgT4rdFRJoJI=@vger.kernel.org X-Gm-Message-State: AOJu0YwWu0w+Bo4Fx4jEO1k4Sa8HwrJRHgKBq/v4X+LmRfx1YTa5YoQF uFojMRwemKy+hjtWZqFQCZS1TCLBJBcOSvVO3zMpcCmD9KtkMSQxSBhz9cC0 X-Gm-Gg: ASbGncsi64Vq0gAmEhJPifIjbrYnxT4jlhOL1+ot7ixcqQE8+YGWtL/HT3/HgBEFC53 l1RCHuTT1VZTGrLaxokbKA3hhNcCVORQLM5qlrRmkIUAHvc9RH6mvNJFk1C54zLnxtw1+ryMQhv DsFlJYsi9RG+pLZRfcJyckFq0rZAxVvFUIdlZ877WeJ9OVd+AMbHZWaGJYbAqoWgymnBpbGxe7K ty0bsm5KDOyantG5h6iA//L6wHwN0tdxQp5hJOmAqEiqji/m+rkplirtfUJlN/7HXMh3bd9pvh0 q1gj7ynoaIk1nlfFw88WPczHQrJsDN83X1vyduk1qGbmPXx7Zv7NGhv4fyr0Hw== X-Google-Smtp-Source: AGHT+IFWSv7o5UfJZsr45iFaTsnSGgjOJ/QEPD95j0N9PVTAsh9E6EiQ4ySP/8hifcKlUKOW3csoJg== X-Received: by 2002:a17:902:d4cd:b0:221:2f4:5446 with SMTP id d9443c01a7336-22104048145mr89810585ad.25.1739695319630; Sun, 16 Feb 2025 00:41:59 -0800 (PST) Received: from VM-119-80-tencentos.localdomain ([14.22.11.165]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-220d5349634sm52681805ad.31.2025.02.16.00.41.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 16 Feb 2025 00:41:59 -0800 (PST) From: Yongliang Gao To: Neeraj.Upadhyay@amd.com, paulmck@kernel.org, frederic@kernel.org, thunder.leizhen@huawei.com Cc: frankjpliu@tencent.com, kernelxing@tencent.com, rcu@vger.kernel.org, linux-kernel@vger.kernel.org, Yongliang Gao , kernel test robot Subject: [PATCH v3] rcu/cpu_stall_cputime: fix the hardirq count for x86 architecture Date: Sun, 16 Feb 2025 16:41:09 +0800 Message-Id: <20250216084109.3109837-1-leonylgao@gmail.com> X-Mailer: git-send-email 2.39.3 Precedence: bulk X-Mailing-List: rcu@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Yongliang Gao When counting the number of hardirqs in the x86 architecture, it is essential to add arch_irq_stat_cpu to ensure accuracy. For example, a CPU loop within the rcu_read_lock function. Before: [ 70.910184] rcu: INFO: rcu_preempt self-detected stall on CPU [ 70.910436] rcu: 3-....: (4999 ticks this GP) idle=*** [ 70.910711] rcu: hardirqs softirqs csw/system [ 70.910870] rcu: number: 0 657 0 [ 70.911024] rcu: cputime: 0 0 2498 ==> 2498(ms) [ 70.911278] rcu: (t=5001 jiffies g=3677 q=29 ncpus=8) After: [ 68.046132] rcu: INFO: rcu_preempt self-detected stall on CPU [ 68.046354] rcu: 2-....: (4999 ticks this GP) idle=*** [ 68.046628] rcu: hardirqs softirqs csw/system [ 68.046793] rcu: number: 2498 663 0 [ 68.046951] rcu: cputime: 0 0 2496 ==> 2496(ms) [ 68.047244] rcu: (t=5000 jiffies g=3825 q=4 ncpus=8) Fixes: be42f00b73a0 ("rcu: Add RCU stall diagnosis information") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202501090842.SfI6QPGS-lkp@intel.com/ Signed-off-by: Yongliang Gao Reviewed-by: Neeraj Upadhyay --- Changes from v2: - Add Reviewed-by 'Neeraj Upadhyay' information - Link to v2: https://lore.kernel.org/all/20250109024652.1342595-1-leonylgao@gmail.com Changes from v1: - Fix compilation error when using arm64-allnoconfig/riscv-randconfig. [kernel test robot] - Link to v1: https://lore.kernel.org/r/20250108065716.2888148-1-leonylgao%40gmail.com --- --- kernel/rcu/tree.c | 10 +++++++--- kernel/rcu/tree.h | 2 +- kernel/rcu/tree_stall.h | 4 ++-- 3 files changed, 10 insertions(+), 6 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 475f31deed14..a0dab5923d03 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -781,6 +781,10 @@ static int rcu_watching_snap_save(struct rcu_data *rdp) return 0; } +#ifndef arch_irq_stat_cpu +#define arch_irq_stat_cpu(cpu) 0 +#endif + /* * Returns positive if the specified CPU has passed through a quiescent state * by virtue of being in or having passed through an dynticks idle state since @@ -916,9 +920,9 @@ static int rcu_watching_snap_recheck(struct rcu_data *rdp) rsrp->cputime_irq = kcpustat_field(kcsp, CPUTIME_IRQ, cpu); rsrp->cputime_softirq = kcpustat_field(kcsp, CPUTIME_SOFTIRQ, cpu); rsrp->cputime_system = kcpustat_field(kcsp, CPUTIME_SYSTEM, cpu); - rsrp->nr_hardirqs = kstat_cpu_irqs_sum(rdp->cpu); - rsrp->nr_softirqs = kstat_cpu_softirqs_sum(rdp->cpu); - rsrp->nr_csw = nr_context_switches_cpu(rdp->cpu); + rsrp->nr_hardirqs = kstat_cpu_irqs_sum(cpu) + arch_irq_stat_cpu(cpu); + rsrp->nr_softirqs = kstat_cpu_softirqs_sum(cpu); + rsrp->nr_csw = nr_context_switches_cpu(cpu); rsrp->jiffies = jiffies; rsrp->gp_seq = rdp->gp_seq; } diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index a9a811d9d7a3..1bba2225e744 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -168,7 +168,7 @@ struct rcu_snap_record { u64 cputime_irq; /* Accumulated cputime of hard irqs */ u64 cputime_softirq;/* Accumulated cputime of soft irqs */ u64 cputime_system; /* Accumulated cputime of kernel tasks */ - unsigned long nr_hardirqs; /* Accumulated number of hard irqs */ + u64 nr_hardirqs; /* Accumulated number of hard irqs */ unsigned int nr_softirqs; /* Accumulated number of soft irqs */ unsigned long long nr_csw; /* Accumulated number of task switches */ unsigned long jiffies; /* Track jiffies value */ diff --git a/kernel/rcu/tree_stall.h b/kernel/rcu/tree_stall.h index 925fcdad5dea..56b21219442b 100644 --- a/kernel/rcu/tree_stall.h +++ b/kernel/rcu/tree_stall.h @@ -435,8 +435,8 @@ static void print_cpu_stat_info(int cpu) rsr.cputime_system = kcpustat_field(kcsp, CPUTIME_SYSTEM, cpu); pr_err("\t hardirqs softirqs csw/system\n"); - pr_err("\t number: %8ld %10d %12lld\n", - kstat_cpu_irqs_sum(cpu) - rsrp->nr_hardirqs, + pr_err("\t number: %8lld %10d %12lld\n", + kstat_cpu_irqs_sum(cpu) + arch_irq_stat_cpu(cpu) - rsrp->nr_hardirqs, kstat_cpu_softirqs_sum(cpu) - rsrp->nr_softirqs, nr_context_switches_cpu(cpu) - rsrp->nr_csw); pr_err("\tcputime: %8lld %10lld %12lld ==> %d(ms)\n",