From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 BA2624F883; Tue, 9 Apr 2024 16:18:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712679531; cv=none; b=LhMo76AITzhTtAxZGvveoen8sZGOYpVq35UN0bAW2o00zMyjY1aDFAlbdJVrHv63I2RF2qZ4OCWKHbfI80D9irqqFdCFFOMzBvjItKzYxgFJ9LV0BUKllQQlDHo1SaV++BlZtZUET7mBWPZcCQz6W80BktMdeM85yG5mGpRWglQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712679531; c=relaxed/simple; bh=a7Fm72paZyRNRsqpCjczySMYH6WBySfKD6PeLYfDdc8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=hIo74OUWufr+LG+sTSFNL6KWCjpJcM5KpBp5u9Nfud64jWD+ELvmjDhr+lIveXNdmpcIOC7j6BPY33XTRt/TsmupO86SkXX9LQXilxRP8rEbUS7m78gzHDYZ0rnkNfmT6qLh9P2uySs7ajA63CChqMRGTd2IN+VJQ0rEKm01Rtk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CbH0ZbOo; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CbH0ZbOo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C6D6C433F1; Tue, 9 Apr 2024 16:18:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1712679531; bh=a7Fm72paZyRNRsqpCjczySMYH6WBySfKD6PeLYfDdc8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CbH0ZbOoWsMrhL0l3zU/ykCadFbwmA849ytybkTc3goAXFXVXT1+T3MHAVioTeAMa HLIOD408RCHYNsYlbVsRzhoQlWayG0IRriXNowb2NudweVWcZQRFS3Qw8o4znU5iSR cl6cjLy5/9VgJEEGo8mmrg4WSMBsaBMS2xHnXICnvD7wZZfjJNsDYhH9un7v5/EUPH qRbOp61cjpMyA5+8D3+iJzXgbfzS5uk98bDmjxA6YjW5HEdb4v2/Qu57TuluRK+oSz qxqSgs/m+yQ1txjhzKkr/SvOQ597RyxCoqGzG8+DYbUiF/ylbrvKq9Ini5ochsFJJg 6ajcY56aBrZhA== From: SeongJae Park To: Honggyu Kim Cc: SeongJae Park , damon@lists.linux.dev, linux-mm@kvack.org, akpm@linux-foundation.org, apopple@nvidia.com, baolin.wang@linux.alibaba.com, dave.jiang@intel.com, hyeongtak.ji@sk.com, kernel_team@skhynix.com, linmiaohe@huawei.com, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, mathieu.desnoyers@efficios.com, mhiramat@kernel.org, rakie.kim@sk.com, rostedt@goodmis.org, surenb@google.com, yangx.jy@fujitsu.com, ying.huang@intel.com, ziy@nvidia.com, 42.hyeyoo@gmail.com, art.jeongseob@gmail.com Subject: Re: [RFC PATCH v3 5/7] mm/damon/paddr: introduce DAMOS_MIGRATE_COLD action for demotion Date: Tue, 9 Apr 2024 09:18:47 -0700 Message-Id: <20240409161847.65803-1-sj@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240409095418.3051-1-honggyu.kim@sk.com> References: Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Honggyu, On Tue, 9 Apr 2024 18:54:14 +0900 Honggyu Kim wrote: > On Mon, 8 Apr 2024 10:52:28 -0700 SeongJae Park wrote: > > On Mon, 8 Apr 2024 21:06:44 +0900 Honggyu Kim wrote: > > > On Fri, 5 Apr 2024 12:24:30 -0700 SeongJae Park wrote: > > > > On Fri, 5 Apr 2024 15:08:54 +0900 Honggyu Kim wrote: [...] > > > I can remove it, but I would like to have more discussion about this > > > issue. The current implementation allows only a single migration > > > target with "target_nid", but users might want to provide fall back > > > migration target nids. > > > > > > For example, if more than two CXL nodes exist in the system, users might > > > want to migrate cold pages to any CXL nodes. In such cases, we might > > > have to make "target_nid" accept comma separated node IDs. nodemask can > > > be better but we should provide a way to change the scanning order. > > > > > > I would like to hear how you think about this. > > > > Good point. I think we could later extend the sysfs file to receive the > > comma-separated numbers, or even mask. For simplicity, adding sysfs files > > dedicated for the different format of inputs could also be an option (e.g., > > target_nids_list, target_nids_mask). But starting from this single node as is > > now looks ok to me. > > If you think we can start from a single node, then I will keep it as is. > But are you okay if I change the same 'target_nid' to accept > comma-separated numbers later? Or do you want to introduce another knob > such as 'target_nids_list'? What about rename 'target_nid' to > 'target_nids' at the first place? I have no strong concern or opinion about this at the moment. Please feel free to renaming it to 'taget_nids' if you think that's better. [...] > Please note that I will be out of office this week so won't be able to > answer quickly. No problem, I hope you to take and enjoy your time :) Thanks, SJ [...]