From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 86958CCF9E3 for ; Thu, 30 Oct 2025 14:36:06 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D043A8E01D3; Thu, 30 Oct 2025 10:36:05 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CDBE28E007D; Thu, 30 Oct 2025 10:36:05 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BF2178E01D3; Thu, 30 Oct 2025 10:36:05 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id ACD668E007D for ; Thu, 30 Oct 2025 10:36:05 -0400 (EDT) Received: from smtpin03.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 58D68139322 for ; 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a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1761834963; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=soAyB09a4gRCbozk32f+xkpt8RLEtWcbpHzWpcmIT3w=; b=Y24nBvjnEnayRH/7VdjqkPINiZgpQKhVHlv4qo03yNsEM3QgsqWRRwvNXDSnmhT5AA2qMh 80GfQFLsvmjpuGIVdZgxwd7oP72lUadmKubBR3L2tew15x/pJGFYitymCmbHPgJ3qrp3xJ 9OBoa7aYqYe7fS/KnbdkP19oXlLkgtk= Received: from unknown (HELO yjaykim-PowerEdge-T330) (10.177.112.156) by 156.147.51.102 with ESMTP; 30 Oct 2025 23:35:58 +0900 X-Original-SENDERIP: 10.177.112.156 X-Original-MAILFROM: youngjun.park@lge.com Date: Thu, 30 Oct 2025 23:35:58 +0900 From: YoungJun Park To: Kairui Song Cc: akpm@linux-foundation.org, linux-mm@kvack.org, shikemeng@huaweicloud.com, kasong@tencent.com, nphamcs@gmail.com, bhe@redhat.com, baohua@kernel.org, chrisl@kernel.org, gunho.lee@lge.com Subject: Re: [PATCH 2/5] mm, swap: Use SWP_SOLIDSTATE to determine if swap is rotational Message-ID: References: <20251029085659.2005942-1-youngjun.park@lge.com> <20251029085659.2005942-3-youngjun.park@lge.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Stat-Signature: 8amg5twxyhjopx7a4b9gnay34uiq9fn3 X-Rspamd-Queue-Id: C9B241C0014 X-Rspamd-Server: rspam06 X-Rspam-User: X-HE-Tag: 1761834962-331289 X-HE-Meta: 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 lrgxKSqR q8kVmU3JrKlj4olYatOnM2dbusXVc7+yDEcZnODLLtb9RTVK5ZQc3Z+pSdWgn6xpS08+egFXgJgHwDz3kOKuSBgCLUyyUzpAE9xJ/HDVf5832f86LAimBKJHWVTzpGlGksXnK1WbNltO9YBpRaZgBcWngP7xzEa2oRhOF22/645mqBVgur7mDjUxngfLjke5j35neaPJyaP0M3uQHh3/2yBTuP0y5o2tIMJKChzC7z6hckC0UlNjTDENYsQAyw8uUcy8yUhqckbQ7la+btj+tM9zpCkFrliw/kzXp X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Oct 30, 2025 at 12:09:29AM +0800, Kairui Song wrote: > On Wed, Oct 29, 2025 at 05:56:56PM +0800, Youngjun Park wrote: > > The current non rotational check is unreliable > > as the device's rotational status can be changed by a user via sysfs. > > > > Use the more reliable SWP_SOLIDSTATE flag which is set at swapon time, > > to ensure the nr_rotate_swap count remains consistent. > > Plus, it is easy to read and simple. > > > > Signed-off-by: Youngjun Park > > --- > > mm/swapfile.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/mm/swapfile.c b/mm/swapfile.c > > index 6dc0e7a738bc..b5d42918c01b 100644 > > --- a/mm/swapfile.c > > +++ b/mm/swapfile.c > > @@ -2913,7 +2913,7 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile) > > if (p->flags & SWP_CONTINUED) > > free_swap_count_continuations(p); > > > > - if (!p->bdev || !bdev_nonrot(p->bdev)) > > + if (!(p->flags & SWP_SOLIDSTATE)) > > atomic_dec(&nr_rotate_swap); > > Good catch. > > Is this introduced by 81a0298bdfab? So we need a Fixes: and backport to stable I think? Okay, I'll add a Fixes tag :) Thanks, Youngjun Park