From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-232.mta1.migadu.com [95.215.58.232]) (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 59C764A5EB2 for ; Mon, 19 Oct 2026 09:44:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.232 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792403065; cv=none; b=CWI9GDqatBZqHQsbIOpgRfnnMTPpPRMk3mk0ycMdqOfVsfrvob9AyfIyVO3Hxna4wTUkaM9HvJwgR8xvjGmKZsX/2YhLWlCVmCjq2vF0/oas4BKOBRLfdLt1QhDLqLhwTfFaYpAMkTx2RVL33xoD4nV9S1Un52wje8jWCqrEJs0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792403065; c=relaxed/simple; bh=e0QRKXqseSbnwv/jNw0BZs0Ci0ks6UPUvoTzc0mkA6U=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=ibie43ljOcjPywrbHBrvFI2EmPvPK5eHyx1RDS16627pMLHQS50ToSfFnTTsDTTRzRQiwWlHntn+lOIfiPipy8qzGjCUrDXXzlGXLYcSHrXEtCdRYqhQeGTgXmBZsZXoKWrRWcFwJBQfqxd1YNqh3uJYo3PaM6f/f9nFGVVlAp8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=BMaBccpM; arc=none smtp.client-ip=95.215.58.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="BMaBccpM" X-Envelope-To: bpf@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=e0QRKXqseSbnwv/jNw0BZs0Ci0ks6UPUvoTzc0mkA6U=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1792403060; v=1; x=1793007860; b=BMaBccpMv3NMSDT1Bd0lgqkLZ9Hcw/VNr3PvN7xr/D9ixiZf51Ma/Yu9HoJmC/dNLPaqTC0n hQDkxRFL1nMlfQuW0pXCk2oH2Mw7jP5U1GRu1G6aKNVcn9wtPl2clD1vIu6ESSEw8BkSg7ndplj fSgChnF961fWYeln4MxeG+Ec= X-Envelope-To: bpf@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 51b1cea30dcf2afa; Mon, 19 Oct 2026 09:44:20 +0000 X-Mizu-Trace-ID: 51b1cea30dcf2afa X-Migadu-Flow: FLOW_OUT Message-ID: <8f67b745-d63f-4d3f-9672-7bad7ce0e436@linux.dev> Date: Mon, 19 Oct 2026 17:44:10 +0800 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: cui.tao@linux.dev, josef@toxicopanda.com, axboe@kernel.dk, cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, andrii@kernel.org, eddyz87@gmail.com, ast@kernel.org, daniel@iogearbox.net, linux-kselftest@vger.kernel.org, Tao Cui , ameryhung@gmail.com, alexei.starovoitov@gmail.com Subject: Re: [RFC PATCH v10 3/4] blk-iocost: add iocost_ioc_tick tracepoint for per-period device summary To: Tejun Heo References: <20261003124045.1289305-1-cui.tao@linux.dev> <20261003124045.1289305-4-cui.tao@linux.dev> From: Tao Cui In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hello Tejun, 在 2026/10/17 01:49, Tejun Heo 写道: > Hello, Tao. > > On Sat, 03 Oct 2026 20:40:44 +0800, Tao Cui wrote: >> + * Periodic per-device summary, emitted once per period from the tail of >> + * ioc_timer_fn(). Unlike the state-change events above, this fires every > > The event is emitted before the vrate adjustment and the period > transition, not from the tail. > Updated both the commit message and the comment to say that the event is emitted before the vrate adjustment and the period transition. >> + /* whether the controller still has active iocgs */ >> + __field(int, running) > > nr_active counts every entry on ioc->active_iocgs, and ioc->lock is held > from the count to the emit point, so running always equals active != 0. > Maybe drop the field? > Dropped, along with the printk column and the corresponding commit message paragraph. With the lock held across the count and the tracepoint emission, it always equals active != 0, so it carries no additional information. Thanks, Tao > Thanks. >