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 06F5DC433EF for ; Wed, 6 Oct 2021 12:13:17 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A756F61166 for ; Wed, 6 Oct 2021 12:13:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org A756F61166 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 394AD940007; Wed, 6 Oct 2021 08:13:16 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 31CB06B0073; Wed, 6 Oct 2021 08:13:16 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 196F2940007; Wed, 6 Oct 2021 08:13:16 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0070.hostedemail.com [216.40.44.70]) by kanga.kvack.org (Postfix) with ESMTP id 069606B0071 for ; Wed, 6 Oct 2021 08:13:16 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id AB8B639488 for ; Wed, 6 Oct 2021 12:13:15 +0000 (UTC) X-FDA: 78665902350.25.113227C Received: from m43-7.mailgun.net (m43-7.mailgun.net [69.72.43.7]) by imf27.hostedemail.com (Postfix) with ESMTP id 3D8C1700801D for ; Wed, 6 Oct 2021 12:13:15 +0000 (UTC) DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1633522395; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: MIME-Version: Date: Message-ID: From: References: Cc: To: Subject: Sender; bh=It/MRNqAXGNPyFh/a1DDiLRtR989/cjNw7hpzBembtQ=; b=VOCGO+FyylnuZe2HSgllvosLO8G+cS8rcmACsm3+lVsM56t9DohsTxsXVBXZl7URccrbFEWG vYUjeoPxCTxVZJOj/ysqmsW9EFWc2EyL0YxVRLS5M+KbJ+avsFP6jf3+sF5i77ulybj9mZzl CgwPob7K6BvyXeq5/ZD7+lRDG/o= X-Mailgun-Sending-Ip: 69.72.43.7 X-Mailgun-Sid: WyIwY2Q3OCIsICJsaW51eC1tbUBrdmFjay5vcmciLCAiYmU5ZTRhIl0= Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n02.prod.us-east-1.postgun.com with SMTP id 615d92dab8ab9916b353f3d5 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 06 Oct 2021 12:13:14 GMT Received: by smtp.codeaurora.org (Postfix, from userid 1001) id B3CAFC43460; Wed, 6 Oct 2021 12:13:13 +0000 (UTC) Received: from [192.168.0.109] (unknown [49.204.182.88]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: faiyazm) by smtp.codeaurora.org (Postfix) with ESMTPSA id 4C39DC4338F; Wed, 6 Oct 2021 12:13:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 smtp.codeaurora.org 4C39DC4338F Subject: Re: [PATCH v1] mm: page_alloc: Add debug log in free_reserved_area for static memory To: David Hildenbrand , akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: guptap@codeaurora.org References: <1632819849-511-1-git-send-email-faiyazm@codeaurora.org> <248ec931-7c16-3e2d-cc8f-8ce0dd4e923b@redhat.com> <0149edd5-fe7f-2786-413c-6de2eab3e30c@codeaurora.org> <1f6708d2-1ca8-6d1f-d9f0-855f2df755ed@codeaurora.org> From: Faiyaz Mohammed Message-ID: <88df48af-901b-5765-d92c-6d14c2b1f73e@codeaurora.org> Date: Wed, 6 Oct 2021 17:43:08 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 3D8C1700801D X-Stat-Signature: 5isp8h9jcu3iiqst37wjn61cjjmfuen4 Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=mg.codeaurora.org header.s=smtp header.b=VOCGO+Fy; dmarc=none; spf=pass (imf27.hostedemail.com: domain of "bounce+d06763.be9e4a-linux-mm=kvack.org@mg.codeaurora.org" designates 69.72.43.7 as permitted sender) smtp.mailfrom="bounce+d06763.be9e4a-linux-mm=kvack.org@mg.codeaurora.org" X-HE-Tag: 1633522395-756244 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: Hi, Sorry for delayed response. On 9/29/2021 10:33 PM, David Hildenbrand wrote: > On 29.09.21 10:58, Faiyaz Mohammed wrote: >> >> >> On 9/28/2021 4:46 PM, David Hildenbrand wrote: >>> On 28.09.21 12:53, Faiyaz Mohammed wrote: >>>> >>>> >>>> On 9/28/2021 4:09 PM, David Hildenbrand wrote: >>>>> On 28.09.21 11:04, Faiyaz Mohammed wrote: >>>>>> For INITRD and initmem memory is reserved through "memblock_reserv= e" >>>>>> during boot up but it is free via "free_reserved_area" instead >>>>>> of "memblock_free". >>>>>> For example: >>>>>> [=C2=A0=C2=A0=C2=A0 0.294848] Freeing initrd memory: 12K. >>>>>> [=C2=A0=C2=A0=C2=A0 0.696688] Freeing unused kernel memory: 4096K. >>>>>> >>>>>> To get the start and end address of the above freed memory and to >>>>>> account >>>>>> proper memblock added memblock_dbg log in "free_reserved_area". >>>>>> After adding log: >>>>>> [=C2=A0=C2=A0=C2=A0 0.294837] memblock_free: [0x00000083600000-0x0= 0000083603000] >>>>>> free_initrd_mem+0x20/0x28 >>>>>> [=C2=A0=C2=A0=C2=A0 0.294848] Freeing initrd memory: 12K. >>>>>> [=C2=A0=C2=A0=C2=A0 0.695246] memblock_free: [0x00000081600000-0x0= 0000081a00000] >>>>>> free_initmem+0x70/0xc8 >>>>>> [=C2=A0=C2=A0=C2=A0 0.696688] Freeing unused kernel memory: 4096K. >>>>>> >>>>>> Signed-off-by: Faiyaz Mohammed >>>>>> --- >>>>>> =C2=A0=C2=A0=C2=A0 mm/page_alloc.c | 5 +++++ >>>>>> =C2=A0=C2=A0=C2=A0 1 file changed, 5 insertions(+) >>>>>> >>>>>> diff --git a/mm/page_alloc.c b/mm/page_alloc.c >>>>>> index b37435c..f85c3b2 100644 >>>>>> --- a/mm/page_alloc.c >>>>>> +++ b/mm/page_alloc.c >>>>>> @@ -8129,6 +8129,11 @@ unsigned long free_reserved_area(void *star= t, >>>>>> void *end, int poison, const char >>>>>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= pr_info("Freeing %s memory: %ldK\n", >>>>>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0 s, pages << (PAGE_SHIFT - 10)); >>>>>> =C2=A0=C2=A0=C2=A0 +#ifdef CONFIG_HAVE_MEMBLOCK >>>>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 memblock_dbg("memblock= _free: [%#016llx-%#016llx] %pS\n", >>>>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= __pa(start), __pa(end), (void *)_RET_IP_); >>>>>> +#endif >>>>> >>>>> IMHO, the "memblock_free" part is misleading. Something was allocat= ed >>>>> early via memblock, then we transitioned to the buddy, now we're >>>>> freeing >>>>> that early allocation via the buddy. >>>>> Yes, we're freeing the early allocation via buddy, but for proper >>>> memblock accounting we need this debug print. >>>> >>> >>> What do you mean with "accounting" ? These are debug statements. >>> >>> >> Yes, these are debug statements, which help to know the a-b address >> belongs to x callsite. This info is required when memblock=3Ddebug is >> passed through command line and CONFIG_HAVE_MEMBLOCK is enabled. >=20 > The issue I'm having is talking in the name of memblock "memblock_dbg, > memblock_free", when memblock might no longer be around. We have other > places where we free early memblock allocations back to the buddy. I didn't find place where we free early memblock allocation back to the buddy. Why "memblock_dbg" print with "memblock_free" string?. - After buddy took over, buddy will free memblock reserved memory through free_reserved_area and it will print the freed memory size, but the freed memory through buddy still be part of memblock.reserved.regions= . - To know the address ranges, added the "memblock_dbg" print along with "membloc_free" string. - If it is misleading or confusing, we can remove the "memblock_free" string from the "memblock_dgb" print and we can just print the address range when "memlock=3Ddebug" pass through command line. Thanks and regards, Mohammed Faiyaz