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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0A8D7C433F5 for ; Wed, 20 Oct 2021 08:15:39 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8A02960F46 for ; Wed, 20 Oct 2021 08:15:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 8A02960F46 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 1C85E6B0071; Wed, 20 Oct 2021 04:15:38 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 177A46B0072; Wed, 20 Oct 2021 04:15:38 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 067986B0073; Wed, 20 Oct 2021 04:15:38 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0178.hostedemail.com [216.40.44.178]) by kanga.kvack.org (Postfix) with ESMTP id EC6636B0071 for ; Wed, 20 Oct 2021 04:15:37 -0400 (EDT) Received: from smtpin34.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id AE9A48249980 for ; Wed, 20 Oct 2021 08:15:37 +0000 (UTC) X-FDA: 78716106714.34.CA85978 Received: from out30-56.freemail.mail.aliyun.com (out30-56.freemail.mail.aliyun.com [115.124.30.56]) by imf16.hostedemail.com (Postfix) with ESMTP id DBBD6F00008C for ; Wed, 20 Oct 2021 08:15:33 +0000 (UTC) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R611e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04395;MF=xhao@linux.alibaba.com;NM=1;PH=DS;RN=5;SR=0;TI=SMTPD_---0Ut1BFcd_1634717731; Received: from B-X3VXMD6M-2058.local(mailfrom:xhao@linux.alibaba.com fp:SMTPD_---0Ut1BFcd_1634717731) by smtp.aliyun-inc.com(127.0.0.1); Wed, 20 Oct 2021 16:15:32 +0800 From: Xin Hao Reply-To: xhao@linux.alibaba.com Subject: Re: [PATCH v3 2/2] mm/damon/dbgfs: Add adaptive_targets list check before enable monitor_on To: SeongJae Park Cc: sjpark@amazon.de, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20211020081233.28363-1-sj@kernel.org> Message-ID: <666ac057-8382-d671-124a-cf34b1dad417@linux.alibaba.com> Date: Wed, 20 Oct 2021 16:15:30 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: <20211020081233.28363-1-sj@kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Authentication-Results: imf16.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=alibaba.com; spf=pass (imf16.hostedemail.com: domain of xhao@linux.alibaba.com designates 115.124.30.56 as permitted sender) smtp.mailfrom=xhao@linux.alibaba.com X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: DBBD6F00008C X-Stat-Signature: 9zyynbpnhnm81fj6ni6f7uin3dnmkdjg X-HE-Tag: 1634717733-593521 Content-Transfer-Encoding: quoted-printable 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: On 2021/10/20 =E4=B8=8B=E5=8D=884:12, SeongJae Park wrote: > On Wed, 20 Oct 2021 07:21:21 +0000 SeongJae Park wrote: > >> On Wed, 20 Oct 2021 09:42:33 +0800 Xin Hao wr= ote: >> >>> When the ctx->adaptive_targets list is empty, >>> I did some test on monitor_on interface like this. >>> >>> # echo > /sys/kernel/debug/damon/target_ids >> Thanks for the change, but you missed writing 'on' to 'monitor_on' in = the above >> example. Sorry. >> >>> Though the ctx->adaptive_targets list is empty, but the >>> kthread_run still be called, and the kdamond.x thread still >>> be created, this is meaningless. >>> >>> So there adds a judgment in 'dbgfs_monitor_on_write', >>> if the ctx->adaptive_targets list is empty, return -EINVAL. >>> >>> Signed-off-by: Xin Hao >> Other parts looks good to me. However, seems this commit conflicts wi= th a >> patch[1] which already merged in -mm tree. Could you please rebase th= is on it? >> FYI, all DAMON patches that merged in -mm tree are also applied on DAM= ON >> development tree. So, you could get the patch applied tree by: >> >> $ git remote add sj git://git.kernel.org/pub/scm/linux/kernel/git= /sj/linux.git >> $ git fetch sj >> $ git checkout 0fa378d04b12 >> >> [1] https://lore.kernel.org/linux-mm/20211014073014.35754-1-sj@kernel.= org/ Ok, i will correct it. >> >> >> Thanks, >> SJ >> >>> --- >>> include/linux/damon.h | 1 + >>> mm/damon/core.c | 5 +++++ >>> mm/damon/dbgfs.c | 13 ++++++++++--- >>> 3 files changed, 16 insertions(+), 3 deletions(-) >>> >>> diff --git a/include/linux/damon.h b/include/linux/damon.h >>> index 715dadd21f7c..4fce5f1f6dad 100644 >>> --- a/include/linux/damon.h >>> +++ b/include/linux/damon.h >>> @@ -316,6 +316,7 @@ void damon_destroy_scheme(struct damos *s); >>> >>> struct damon_target *damon_new_target(unsigned long id); >>> void damon_add_target(struct damon_ctx *ctx, struct damon_target *t= ); >>> +bool damon_targets_empty(struct damon_ctx *ctx); >>> void damon_free_target(struct damon_target *t); >>> void damon_destroy_target(struct damon_target *t); >>> unsigned int damon_nr_regions(struct damon_target *t); >>> diff --git a/mm/damon/core.c b/mm/damon/core.c >>> index 2f6785737902..c3a1374dbe0b 100644 >>> --- a/mm/damon/core.c >>> +++ b/mm/damon/core.c >>> @@ -156,6 +156,11 @@ void damon_add_target(struct damon_ctx *ctx, str= uct damon_target *t) >>> list_add_tail(&t->list, &ctx->adaptive_targets); >>> } >>> >>> +bool damon_targets_empty(struct damon_ctx *ctx) >>> +{ >>> + return list_empty(&ctx->adaptive_targets); >>> +} >>> + >>> static void damon_del_target(struct damon_target *t) >>> { >>> list_del(&t->list); >>> diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c >>> index 38188347d8ab..9dee29f7d103 100644 >>> --- a/mm/damon/dbgfs.c >>> +++ b/mm/damon/dbgfs.c >>> @@ -865,12 +865,19 @@ static ssize_t dbgfs_monitor_on_write(struct fi= le *file, >>> return -EINVAL; >>> } >>> >>> - if (!strncmp(kbuf, "on", count)) >>> + if (!strncmp(kbuf, "on", count)) { >>> + int i; >>> + >>> + for (i =3D 0; i < dbgfs_nr_ctxs; i++) { >>> + if (damon_targets_empty(dbgfs_ctxs[i])) >>> + return -EINVAL; > Oops, I forgot that you should 'kfree(kbuf)' before returning here. Pl= ease do > that. Okay,=C2=A0 i will correct it, thank you. > > Thanks, > SJ > >>> + } >>> err =3D damon_start(dbgfs_ctxs, dbgfs_nr_ctxs); >>> - else if (!strncmp(kbuf, "off", count)) >>> + } else if (!strncmp(kbuf, "off", count)) { >>> err =3D damon_stop(dbgfs_ctxs, dbgfs_nr_ctxs); >>> - else >>> + } else { >>> err =3D -EINVAL; >>> + } >>> >>> if (err) >>> ret =3D err; >>> -- >>> 2.31.0 >> --=20 Best Regards! Xin Hao