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 C393318C35B for ; Mon, 15 Jul 2024 15:21:34 +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=1721056894; cv=none; b=rTK6BZeIdOjLJpODGYzz4LLGT1VfHGGVnJKqTECOoRH0QxyMyejt9/DXfEbCWl3i76Z7puMVEZJk03H900M80wGK/p3K2z8wCwn1tGwIvrH/w39TnjaHAopd6vSob7Ef2SvHB27QrIH/HJtQlSDa2/DP/PJWenPtU35WSV28AaQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721056894; c=relaxed/simple; bh=JZ33jT8IC8r7jk171HMCeY5ZfAwmlRKd5yUYKLz3nNc=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=KgzyozXTeSEXzir38eoPeDqbvfQ9T5/4UBVtwxbTABBheiOdVKxVyqQsg5HtZOFoilHOhf+rC85bklbY1ngC8R6404cqgVJX57RPWOr0efBlBGy5x5oA2iT9aSaH0qbhKRgBSiubSAbGmdr1txnTGAca3f9qckEQ+4yQeGqOZJg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=b78LWNtC; 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="b78LWNtC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B766CC4AF0D; Mon, 15 Jul 2024 15:21:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1721056894; bh=JZ33jT8IC8r7jk171HMCeY5ZfAwmlRKd5yUYKLz3nNc=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=b78LWNtCvk5B6l+0KcaioRSwOdo3syIGBmAC1PLRCHA8l5WLOCWq2602OrU/pAGwE 9djDzuMSJ1i5Z31bwz8TrQAvQQtvskL7/VyQs5KRBEN8klarWGEdgK8gydbOsQHT6r EnzbYL+OXGfrP1irL11M1olmS4NUnID1nSHqQV7+F2pjYhMLpIP+YzPoPMBet4I5Gq Q9gn/A8XRgbEFnld0qsNUYCe5qSrHowIAQo3zjEFy+ZdPXS5W+wKhVXYhElLDp7w9n g6VhB4tEMkCxpTAZ5yX2foSa7sM6SFHRMLoUISfvOyDBJSKjgQ5SP6zbT8TRLSTEFx uth3oeyCFWO1w== Message-ID: Subject: Re: [PATCH 09/14] nfsd: return hard failure for OP_SETCLIENTID when there are too many clients. From: Jeff Layton To: NeilBrown , Chuck Lever Cc: linux-nfs@vger.kernel.org, Olga Kornievskaia , Dai Ngo , Tom Talpey , Steve Dickson Date: Mon, 15 Jul 2024 11:21:32 -0400 In-Reply-To: <20240715074657.18174-10-neilb@suse.de> References: <20240715074657.18174-1-neilb@suse.de> <20240715074657.18174-10-neilb@suse.de> Autocrypt: addr=jlayton@kernel.org; prefer-encrypt=mutual; keydata=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 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.50.4 (3.50.4-1.fc39) Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Mon, 2024-07-15 at 17:14 +1000, NeilBrown wrote: > If there are more non-courteous clients than the calculated limit, we > should fail the request rather than report a soft failure and > encouraging the client to retry indefinitely. >=20 > If there a courteous clients which push us over the limit, then expedite > their removal. >=20 > This is not known to have caused a problem is production use, but > testing of lots of clients reports repeated NFS4ERR_DELAY responses > which doesn't seem helpful. >=20 > Also remove an outdated comment - we do use a slab cache. >=20 > Signed-off-by: NeilBrown > --- > =C2=A0fs/nfsd/nfs4state.c | 23 +++++++++++++---------- > =C2=A01 file changed, 13 insertions(+), 10 deletions(-) >=20 > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > index a20c2c9d7d45..88936f3189e1 100644 > --- a/fs/nfsd/nfs4state.c > +++ b/fs/nfsd/nfs4state.c > @@ -2212,21 +2212,20 @@ STALE_CLIENTID(clientid_t *clid, struct nfsd_net = *nn) > =C2=A0 return 1; > =C2=A0} > =C2=A0 > -/*=20 > - * XXX Should we use a slab cache ? > - * This type of memory management is somewhat inefficient, but we use it > - * anyway since SETCLIENTID is not a common operation. > - */ > =C2=A0static struct nfs4_client *alloc_client(struct xdr_netobj name, > =C2=A0 struct nfsd_net *nn) > =C2=A0{ > =C2=A0 struct nfs4_client *clp; > =C2=A0 int i; > =C2=A0 > - if (atomic_read(&nn->nfs4_client_count) >=3D nn->nfs4_max_clients) { > + if (atomic_read(&nn->nfs4_client_count) - > + =C2=A0=C2=A0=C2=A0 atomic_read(&nn->nfsd_courtesy_clients) >=3D nn->nfs= 4_max_clients) > + return ERR_PTR(-EREMOTEIO); > + nit: I know it gets remapped, but why EREMOTEIO? From nfsd's standpoint this would seem to imply a problem on the client. Maybe: #define EUSERS 87 /* Too many users */ ...instead? > + if (atomic_read(&nn->nfs4_client_count) >=3D nn->nfs4_max_clients && > + =C2=A0=C2=A0=C2=A0 atomic_read(&nn->nfsd_courtesy_clients) > 0) > =C2=A0 mod_delayed_work(laundry_wq, &nn->laundromat_work, 0); > - return NULL; > - } > + > =C2=A0 clp =3D kmem_cache_zalloc(client_slab, GFP_KERNEL); > =C2=A0 if (clp =3D=3D NULL) > =C2=A0 return NULL; > @@ -3115,8 +3114,8 @@ static struct nfs4_client *create_client(struct xdr= _netobj name, > =C2=A0 struct dentry *dentries[ARRAY_SIZE(client_files)]; > =C2=A0 > =C2=A0 clp =3D alloc_client(name, nn); > - if (clp =3D=3D NULL) > - return NULL; > + if (IS_ERR_OR_NULL(clp)) > + return clp; > =C2=A0 > =C2=A0 ret =3D copy_cred(&clp->cl_cred, &rqstp->rq_cred); > =C2=A0 if (ret) { > @@ -3498,6 +3497,8 @@ nfsd4_exchange_id(struct svc_rqst *rqstp, struct nf= sd4_compound_state *cstate, > =C2=A0 new =3D create_client(exid->clname, rqstp, &verf); > =C2=A0 if (new =3D=3D NULL) > =C2=A0 return nfserr_jukebox; > + if (IS_ERR(new)) > + return nfserr_resource; > =C2=A0 status =3D copy_impl_id(new, exid); > =C2=A0 if (status) > =C2=A0 goto out_nolock; > @@ -4416,6 +4417,8 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nf= sd4_compound_state *cstate, > =C2=A0 new =3D create_client(clname, rqstp, &clverifier); > =C2=A0 if (new =3D=3D NULL) > =C2=A0 return nfserr_jukebox; > + if (IS_ERR(new)) > + return nfserr_resource; > =C2=A0 spin_lock(&nn->client_lock); > =C2=A0 conf =3D find_confirmed_client_by_name(&clname, nn); > =C2=A0 if (conf && client_has_state(conf)) { Patch looks fine otherwise though. Reviewed-by: Jeff Layton