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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48CD6C433DF for ; Mon, 22 Jun 2020 08:37:36 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 13140206C3 for ; Mon, 22 Jun 2020 08:37:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 13140206C3 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=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A03C96B0002; Mon, 22 Jun 2020 04:37:35 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9B3BF6B0005; Mon, 22 Jun 2020 04:37:35 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8C92A6B0006; Mon, 22 Jun 2020 04:37:35 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0167.hostedemail.com [216.40.44.167]) by kanga.kvack.org (Postfix) with ESMTP id 736D26B0002 for ; Mon, 22 Jun 2020 04:37:35 -0400 (EDT) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id E61912C8B for ; Mon, 22 Jun 2020 08:37:34 +0000 (UTC) X-FDA: 76956194028.26.fan29_5a1030326e31 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin26.hostedemail.com (Postfix) with ESMTP id BDCDF1804B668 for ; Mon, 22 Jun 2020 08:37:34 +0000 (UTC) X-HE-Tag: fan29_5a1030326e31 X-Filterd-Recvd-Size: 5970 Received: from out30-57.freemail.mail.aliyun.com (out30-57.freemail.mail.aliyun.com [115.124.30.57]) by imf10.hostedemail.com (Postfix) with ESMTP for ; Mon, 22 Jun 2020 08:37:33 +0000 (UTC) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R181e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e07484;MF=richard.weiyang@linux.alibaba.com;NM=1;PH=DS;RN=11;SR=0;TI=SMTPD_---0U0K3ntX_1592815044; Received: from localhost(mailfrom:richard.weiyang@linux.alibaba.com fp:SMTPD_---0U0K3ntX_1592815044) by smtp.aliyun-inc.com(127.0.0.1); Mon, 22 Jun 2020 16:37:24 +0800 Date: Mon, 22 Jun 2020 16:37:24 +0800 From: Wei Yang To: David Hildenbrand Cc: Dan Williams , Linux Kernel Mailing List , Linux MM , Andrew Morton , Johannes Weiner , Michal Hocko , Minchan Kim , Huang Ying , Wei Yang , Mel Gorman Subject: Re: [PATCH v2 3/3] mm/shuffle: remove dynamic reconfiguration Message-ID: <20200622083724.GA96508@L-31X9LVDL-1304.local> Reply-To: Wei Yang References: <20200619125923.22602-1-david@redhat.com> <20200619125923.22602-4-david@redhat.com> <7a5f9ea1-7405-7058-af60-eea0bc165e79@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7a5f9ea1-7405-7058-af60-eea0bc165e79@redhat.com> X-Rspamd-Queue-Id: BDCDF1804B668 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam05 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 Mon, Jun 22, 2020 at 09:33:28AM +0200, David Hildenbrand wrote: >On 20.06.20 03:49, Dan Williams wrote: >> On Fri, Jun 19, 2020 at 5:59 AM David Hildenbrand wrote: >>> >>> Commit e900a918b098 ("mm: shuffle initial free memory to improve >>> memory-side-cache utilization") promised "autodetection of a >>> memory-side-cache (to be added in a follow-on patch)" over a year ago. >>> >>> The original series included patches [1], however, they were dropped >>> during review [2] to be followed-up later. >>> >>> Due to lack of platforms that publish an HMAT, autodetection is currently >>> not implemented. However, manual activation is actively used [3]. Let's >>> simplify for now and re-add when really (ever?) needed. >>> >>> [1] https://lkml.kernel.org/r/154510700291.1941238.817190985966612531.stgit@dwillia2-desk3.amr.corp.intel.com >>> [2] https://lkml.kernel.org/r/154690326478.676627.103843791978176914.stgit@dwillia2-desk3.amr.corp.intel.com >>> [3] https://lkml.kernel.org/r/CAPcyv4irwGUU2x+c6b4L=KbB1dnasNKaaZd6oSpYjL9kfsnROQ@mail.gmail.com >>> >>> Cc: Andrew Morton >>> Cc: Johannes Weiner >>> Cc: Michal Hocko >>> Cc: Minchan Kim >>> Cc: Huang Ying >>> Cc: Wei Yang >>> Cc: Mel Gorman >>> Cc: Dan Williams >>> Signed-off-by: David Hildenbrand >>> --- >>> mm/shuffle.c | 28 ++-------------------------- >>> mm/shuffle.h | 17 ----------------- >>> 2 files changed, 2 insertions(+), 43 deletions(-) >>> >>> diff --git a/mm/shuffle.c b/mm/shuffle.c >>> index dd13ab851b3ee..9b5cd4b004b0f 100644 >>> --- a/mm/shuffle.c >>> +++ b/mm/shuffle.c >>> @@ -10,33 +10,11 @@ >>> #include "shuffle.h" >>> >>> DEFINE_STATIC_KEY_FALSE(page_alloc_shuffle_key); >>> -static unsigned long shuffle_state __ro_after_init; >>> - >>> -/* >>> - * Depending on the architecture, module parameter parsing may run >>> - * before, or after the cache detection. SHUFFLE_FORCE_DISABLE prevents, >>> - * or reverts the enabling of the shuffle implementation. SHUFFLE_ENABLE >>> - * attempts to turn on the implementation, but aborts if it finds >>> - * SHUFFLE_FORCE_DISABLE already set. >>> - */ >>> -__meminit void page_alloc_shuffle(enum mm_shuffle_ctl ctl) >>> -{ >>> - if (ctl == SHUFFLE_FORCE_DISABLE) >>> - set_bit(SHUFFLE_FORCE_DISABLE, &shuffle_state); >>> - >>> - if (test_bit(SHUFFLE_FORCE_DISABLE, &shuffle_state)) { >>> - if (test_and_clear_bit(SHUFFLE_ENABLE, &shuffle_state)) >>> - static_branch_disable(&page_alloc_shuffle_key); >>> - } else if (ctl == SHUFFLE_ENABLE >>> - && !test_and_set_bit(SHUFFLE_ENABLE, &shuffle_state)) >>> - static_branch_enable(&page_alloc_shuffle_key); >>> -} >>> >>> static bool shuffle_param; >>> static int shuffle_show(char *buffer, const struct kernel_param *kp) >>> { >>> - return sprintf(buffer, "%c\n", test_bit(SHUFFLE_ENABLE, &shuffle_state) >>> - ? 'Y' : 'N'); >>> + return sprintf(buffer, "%c\n", shuffle_param ? 'Y' : 'N'); >>> } >>> >>> static __meminit int shuffle_store(const char *val, >>> @@ -47,9 +25,7 @@ static __meminit int shuffle_store(const char *val, >>> if (rc < 0) >>> return rc; >>> if (shuffle_param) >>> - page_alloc_shuffle(SHUFFLE_ENABLE); >>> - else >>> - page_alloc_shuffle(SHUFFLE_FORCE_DISABLE); >>> + static_branch_enable(&page_alloc_shuffle_key); >>> return 0; >>> } >> >> Let's do proper input validation here and require 1 / 'true' to enable >> shuffling and not also allow 0 to be an 'enable' value. > >I don't think that's currently done? > >param_set_bool(val, kp) will only default val==NULL to 'true'. Passing 0 >will properly be handled by strtobool(). Or am I missing something? > Agree with this statement. >Thanks! > >-- >Thanks, > >David / dhildenb -- Wei Yang Help you, Help me