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 0F823184116 for ; Fri, 14 Jun 2024 02:48:18 +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=1718333301; cv=none; b=OV6493Xj4c6TAbGIzomN0OmAC5A4kUBeWEcaJak2f6122nOJ7Cq//oAv1KE0WKPMBVAVPposet7Yohc+ReQ/aO8+tom/A8/Tz6OuB+BeHHs1Z9JQiD1SYTIe1h6D5YbjN9FMd011vAEZ6EwkKoH9+3DDLsd8jVPGZEbm2me/DBM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718333301; c=relaxed/simple; bh=1YoPP/KFuVlpzsYsMmO/52Yaf/qvfufpUVKcnkocOBU=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=IRhNerw5zVjKyBS1uvCZhdo3ZRPP8NNrsJ7BmrAgt2yWTWjpUUT4+Ekzz6nMtOOePJ5pzDEsNwtFHeTfO+WSr5EnYKtSLexCWbLgzGeQC+AXXsZVGpzUG5a7AmKbCrCD9ij6oOapmbFcx7mDqhFkTmgh+oIBB5Mqy1KtJmUERXI= 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 [172.19.162.112]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4W0kFL6ZScz3PsZk; Fri, 14 Jun 2024 10:46:46 +0800 (CST) Received: from kwepemi100008.china.huawei.com (unknown [7.221.188.57]) by mail.maildlp.com (Postfix) with ESMTPS id E7B2A1401E9; Fri, 14 Jun 2024 10:48:10 +0800 (CST) Received: from [10.67.109.254] (10.67.109.254) by kwepemi100008.china.huawei.com (7.221.188.57) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Fri, 14 Jun 2024 10:48:10 +0800 Message-ID: <4dabec63-66bf-b13a-de00-287157cf80ef@huawei.com> Date: Fri, 14 Jun 2024 10:48:08 +0800 Precedence: bulk X-Mailing-List: linux-kernel@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/102.2.0 Subject: Re: [PATCH] arm64: smp: Fix missing IPI statistics Content-Language: en-US To: Doug Anderson CC: , , , , , , , , , References: <20240607074716.4068975-1-ruanjinjie@huawei.com> From: Jinjie Ruan In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To kwepemi100008.china.huawei.com (7.221.188.57) On 2024/6/8 0:02, Doug Anderson wrote: > Hi, > > On Fri, Jun 7, 2024 at 12:45 AM Jinjie Ruan wrote: >> >> commit 83cfac95c018 ("genirq: Allow interrupts to be excluded from >> /proc/interrupts") is to avoid IPIs appear twice in /proc/interrupts. >> But the commit 331a1b3a836c ("arm64: smp: Add arch support for backtrace >> using pseudo-NMI") and commit 2f5cd0c7ffde("arm64: kgdb: Implement >> kgdb_roundup_cpus() to enable pseudo-NMI roundup") set CPU_BACKTRACE and >> KGDB_ROUNDUP IPIs "IRQ_HIDDEN" flag but not show them in >> arch_show_interrupts(), which cause the interrupt kstat_irqs accounting >> is missing in display. >> >> Fixes: 331a1b3a836c ("arm64: smp: Add arch support for backtrace using pseudo-NMI") >> Signed-off-by: Jinjie Ruan >> --- >> arch/arm64/kernel/smp.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) > > While I won't object to your patch if everyone agrees that we want it, Hello, What's everyone's opinion? > fully excluding "cpu backtrace" and "kgdb roundup" from > /proc/interrupts was more of a design decision than a bug. Those two > IPIs are really special cases and not something that I'd expect anyone > to care about knowing the count of. Keeping them out of > "/proc/interrupts" just avoids noise. I'd also note that I believe > arm32 makes the same design choice for "cpu backtrace". Yes, arm32 is same as arm64. > > In any case, if we truly think people want the count of these IPIs > then it feels like we should report them in arch_show_interrupts() > where we can give them a nice string. That's a good idea. > > -Doug