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[216.228.121.65]) by mx.google.com with ESMTPS id g23si507284otj.307.2019.06.06.20.40.09 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 06 Jun 2019 20:40:09 -0700 (PDT) Received-SPF: pass (google.com: domain of jhubbard@nvidia.com designates 216.228.121.65 as permitted sender) client-ip=216.228.121.65; Authentication-Results: mx.google.com; dkim=pass header.i=@nvidia.com header.s=n1 header.b=G1lFsOJU; spf=pass (google.com: domain of jhubbard@nvidia.com designates 216.228.121.65 as permitted sender) smtp.mailfrom=jhubbard@nvidia.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=nvidia.com Received: from hqpgpgate102.nvidia.com (Not Verified[216.228.121.13]) by hqemgate16.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Thu, 06 Jun 2019 20:40:08 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate102.nvidia.com (PGP Universal service); Thu, 06 Jun 2019 20:40:08 -0700 X-PGP-Universal: processed; by hqpgpgate102.nvidia.com on Thu, 06 Jun 2019 20:40:08 -0700 Received: from [10.110.48.28] (10.124.1.5) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Fri, 7 Jun 2019 03:40:08 +0000 Subject: Re: [PATCH v2 hmm 10/11] mm/hmm: Do not use list*_rcu() for hmm->ranges To: Jason Gunthorpe , Jerome Glisse , "Ralph Campbell" , CC: , , Andrea Arcangeli , , , Jason Gunthorpe References: <20190606184438.31646-1-jgg@ziepe.ca> <20190606184438.31646-11-jgg@ziepe.ca> X-Nvconfidentiality: public From: John Hubbard Message-ID: <59b5de4b-e872-30f4-149e-f8a3bc946f22@nvidia.com> Date: Thu, 6 Jun 2019 20:40:07 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <20190606184438.31646-11-jgg@ziepe.ca> X-Originating-IP: [10.124.1.5] X-ClientProxiedBy: HQMAIL104.nvidia.com (172.18.146.11) To HQMAIL107.nvidia.com (172.20.187.13) Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: quoted-printable DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1559878808; bh=pa8me+rakZWDjEypIvJVJP7U7jLDmCrHPlreNoxTeR8=; h=X-PGP-Universal:Subject:To:CC:References:X-Nvconfidentiality:From: Message-ID:Date:User-Agent:MIME-Version:In-Reply-To: X-Originating-IP:X-ClientProxiedBy:Content-Type:Content-Language: Content-Transfer-Encoding; b=G1lFsOJUt+3jxL5x/uSOUxqaW8LvFvibp6A1hycDOeXtZ3mAVTRD5L3VKP0+kejUe plHS/p/eAzx3ex2XvNWSsTCNfKzMxe6E+GIKyEeyTNz3eSluzrCzSvLLKtXOp+RwaI voG1xUgVGSn8ma6EEdNcmXRkz1nklW0nF4LIQrahYEMP2+v0xepaEdhjPoULnG84Qp EDLZE60nNdaLX38kGT9lcb2ftfpDNdj31aqY2OYsEJ2m2Fb88xd/ujlbrFDIGrhXl3 wYDlYNzBx0QOfzYwjwKgB+ND6ZyLRRb32g3Q1tZd7Iqq+9mp7WwLSdXx/jOveKZLKX LKsPn6DIVkigg== 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 6/6/19 11:44 AM, Jason Gunthorpe wrote: > From: Jason Gunthorpe >=20 > This list is always read and written while holding hmm->lock so there is > no need for the confusing _rcu annotations. >=20 > Signed-off-by: Jason Gunthorpe > Reviewed-by: J=C3=A9r=C3=B4me Glisse > --- > mm/hmm.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) >=20 > diff --git a/mm/hmm.c b/mm/hmm.c > index c2fecb3ecb11e1..709d138dd49027 100644 > --- a/mm/hmm.c > +++ b/mm/hmm.c > @@ -911,7 +911,7 @@ int hmm_range_register(struct hmm_range *range, > mutex_lock(&hmm->lock); > =20 > range->hmm =3D hmm; > - list_add_rcu(&range->list, &hmm->ranges); > + list_add(&range->list, &hmm->ranges); > =20 > /* > * If there are any concurrent notifiers we have to wait for them for > @@ -941,7 +941,7 @@ void hmm_range_unregister(struct hmm_range *range) > return; > =20 > mutex_lock(&hmm->lock); > - list_del_rcu(&range->list); > + list_del(&range->list); > mutex_unlock(&hmm->lock); > =20 > /* Drop reference taken by hmm_range_register() */ >=20 Good point. I'd overlooked this many times. Reviewed-by: John Hubbard thanks, --=20 John Hubbard NVIDIA