From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 009.lax.mailroute.net (009.lax.mailroute.net [199.89.1.12]) (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 9657E2C684 for ; Mon, 5 Aug 2024 17:20:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=199.89.1.12 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722878420; cv=none; b=Kg0FFyd9HISi/2TjTXcfGe1gUixPMlHBfr61TiCVtF3UlE3a3g7ulsCC/+opG/FgBt0XlNA5AqK9w6IZEN/n/gtDSzEQ0s8WRq7P30I7x9ns8rHClpS7RepWeDuMa42Wo71e2YbY0NugAcUBR+ylXOyKH+VbDISSSr6rJoXBW4E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722878420; c=relaxed/simple; bh=Vm4yMYfHk7sUfETb2wD1qNaftrwKjOTuk6DyOAThqDk=; h=Message-ID:Date:MIME-Version:From:Subject:To:Cc:References: In-Reply-To:Content-Type; b=RB60m7Z5vLuLl8Q6b+6NsdXbXjlmzhpPog0hEcoqRknfTYsvgEGE1L5zSeNgbWk2+4FKDHeG+MuVd+1hWwmvHa6qrymcs4O9GxcCqcVzI0PJ19l/GCzixvq8U5hhkXfZbt6EEU2QAtUCxA663NDe0tPfnQJmHjMzf8PyPuT0Bgw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org; spf=pass smtp.mailfrom=acm.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b=4sx226/O; arc=none smtp.client-ip=199.89.1.12 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=acm.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b="4sx226/O" Received: from localhost (localhost [127.0.0.1]) by 009.lax.mailroute.net (Postfix) with ESMTP id 4Wd3684Bf1zlgVnF; Mon, 5 Aug 2024 17:17:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=acm.org; h= content-transfer-encoding:content-type:content-type:in-reply-to :content-language:references:subject:subject:from:from :user-agent:mime-version:date:date:message-id:received:received; s=mr01; t=1722878250; x=1725470251; bh=PlP8qE/eEBDg5RIRVuFyaqMI 7U6+MwEbl5t5FoaxRr0=; b=4sx226/Ot0iIJlrTnLIdVZAhBXJZgwDWBq1wUD2C 1gImEOPb6v8FUG4+jloLfUP8aq5+szzVtU4WiwOEo+obvrKlmSiU7A4jQPRWc0kx aoWTlJf4KANoArquU3Y8u20CLJpSkIbj3fDExtXha6jRtNJWCnKtr71fhk98f2SV FakuKxYuCBOU0GTQ1fcAcEgv8SCWxIku7HcvHmQ7/AzH1yHdNs6wde9le8q6HOyS jelgyvouI60ZqRlDS7CeodAD9okYkMu3kX+3MldjPNLFvD7SARoLztAgzcj3KmBA SO0M8l+L1+T2GjOpiQ3TWYKw/LwbBBF54en+PVhyqhiS/Q== X-Virus-Scanned: by MailRoute Received: from 009.lax.mailroute.net ([127.0.0.1]) by localhost (009.lax [127.0.0.1]) (mroute_mailscanner, port 10029) with LMTP id ciTBkFhPgK5m; Mon, 5 Aug 2024 17:17:30 +0000 (UTC) Received: from [100.66.154.22] (unknown [104.135.204.82]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bvanassche@acm.org) by 009.lax.mailroute.net (Postfix) with ESMTPSA id 4Wd3601HNYzlgTGW; Mon, 5 Aug 2024 17:17:27 +0000 (UTC) Message-ID: <25909f08-12a5-4625-839d-9e31df4c9c72@acm.org> Date: Mon, 5 Aug 2024 10:17:27 -0700 Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Bart Van Assche Subject: Re: Regarding patch "block/blk-mq: Don't complete locally if capacities are different" To: Qais Yousef , Christian Loehle Cc: MANISH PANDEY , axboe@kernel.dk, mingo@kernel.org, peterz@infradead.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, linux-block@vger.kernel.org, sudeep.holla@arm.com, Jaegeuk Kim , Christoph Hellwig , kailash@google.com, tkjos@google.com, dhavale@google.com, bvanassche@google.com, quic_nitirawa@quicinc.com, quic_cang@quicinc.com, quic_rampraka@quicinc.com, quic_narepall@quicinc.com References: <10c7f773-7afd-4409-b392-5d987a4024e4@quicinc.com> <3feb5226-7872-432b-9781-29903979d34a@arm.com> <20240805020748.d2tvt7c757hi24na@airbuntu> Content-Language: en-US In-Reply-To: <20240805020748.d2tvt7c757hi24na@airbuntu> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 8/4/24 7:07 PM, Qais Yousef wrote: > irqbalancers usually move the interrupts, and I'm not sure we can > make an assumption about the reason an interrupt is triggering on > different capacity CPU. User space software can't modify the affinity of managed interrupts. From include/linux/irq.h: * IRQD_AFFINITY_MANAGED - Affinity is auto-managed by the kernel That flag is tested by the procfs code that implements the smp_affinity procfs attribute: static ssize_t write_irq_affinity(int type, struct file *file, const char __user *buffer, size_t count, loff_t *pos) { [ ... ] if (!irq_can_set_affinity_usr(irq) || no_irq_affinity) return -EIO; [ ... ] } I'm not sure whether or not the interrupts on Manish test setup are managed. Manish, can you please provide the output of the following commands? adb shell 'grep -i ufshcd /proc/interrupts' adb shell 'grep -i ufshcd /proc/interrupts | while read a b; do ls -ld /proc/irq/${a%:}/smp_affinity; done' adb shell 'grep -i ufshcd /proc/interrupts | while read a b; do grep -aH . /proc/irq/${a%:}/smp_affinity; done' Thanks, Bart.