From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754131AbaIOQgx (ORCPT ); Mon, 15 Sep 2014 12:36:53 -0400 Received: from bues.ch ([80.190.117.144]:42389 "EHLO bues.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753975AbaIOQgw (ORCPT ); Mon, 15 Sep 2014 12:36:52 -0400 X-Greylist: delayed 1342 seconds by postgrey-1.27 at vger.kernel.org; Mon, 15 Sep 2014 12:36:51 EDT Date: Mon, 15 Sep 2014 18:13:31 +0200 From: Michael =?UTF-8?B?QsO8c2No?= To: Amos Kong Cc: virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, herbert@gondor.apana.org.au, mpm@selenic.com, rusty@rustcorp.com.au, amit.shah@redhat.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/3] hw_random: increase schedule timeout in rng_dev_read() Message-ID: <20140915181331.4e3f5fed@wiggum> In-Reply-To: <1410796949-2221-4-git-send-email-akong@redhat.com> References: <1410796949-2221-1-git-send-email-akong@redhat.com> <1410796949-2221-4-git-send-email-akong@redhat.com> X-Mailer: Claws Mail 3.10.1 (GTK+ 2.24.24; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/k2AhhoIPntp+aTxsAG=dZk/"; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Sig_/k2AhhoIPntp+aTxsAG=dZk/ Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Tue, 16 Sep 2014 00:02:29 +0800 Amos Kong wrote: > This patch increases the schedule timeout to 10 jiffies, it's more > appropriate, then other takes can easy to hold the mutex lock. >=20 > Signed-off-by: Amos Kong > --- > drivers/char/hw_random/core.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) >=20 > diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c > index 263a370..b5d1b6f 100644 > --- a/drivers/char/hw_random/core.c > +++ b/drivers/char/hw_random/core.c > @@ -195,7 +195,7 @@ static ssize_t rng_dev_read(struct file *filp, char _= _user *buf, > =20 > mutex_unlock(&rng_mutex); > =20 > - schedule_timeout_interruptible(1); > + schedule_timeout_interruptible(10); > =20 > if (signal_pending(current)) { > err =3D -ERESTARTSYS; Does a schedule of 1 ms or 10 ms decrease the throughput? I think we need some benchmarks. --=20 Michael --Sig_/k2AhhoIPntp+aTxsAG=dZk/ Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBAgAGBQJUFxArAAoJEPUyvh2QjYsOGCsQAJK4Wd0MLbTsJSE0dnSuW7zm +lF26LyK0hZJDv84A1SO9/KxnGLAPVNsdZWPCQ2G27OMxOZ6NLIbHJqdSoIImF7L Y4EncdeOKFmu+W78PxqgJV03LkBTmgQUF+mf9bMr7GGFu25VriM5/fqJkMygjA95 xI0lKPoaPKVlHTNnZSxi/+b10vNCD5/8r+OU3keoSeOQ59UwPLpPJBwHvMB58cEh 7MZ3irpQwZfQajkD7nB7351tXekxy4MimHOPwWSoem9BhFwzxzRSlcIKwgWR0Dyi Khmjqn5sG4GDvWTy/f1Cmuubsr5giWOsnjGtIGTfMwLHXGx7rOgYnSPbShnGNJzN NDDf2v+BfNIHEuPTSeh3M86pd7NR/rTjB8ZuhhvGfk0IaU6R4j21wTeV1w5cWT1n UpBKH7jJmwot/Qss4QIVaDhmFOqzgRfqumGirJbhEMqQp/L9SaKLWnE/GtSkXXSJ Ov8ACjmuR6/sqQEJ/zos7f5lhEKGxBzfgeDFT5mVwCpyAUMnOrXWlvsTWpbi+RiV kwQ960ok6/SIE4Qw3KFQsCjR0/S9wM00rT2PfAGUJN2czpMDf157Ip3thk4tg2/0 K59x4FJt1Or1GGJdi0+sNLH3zgoqwGNIDhPt8IsC7yMG35/CZDD7NzRqpud9Y64k Wf/71D5PPuyFe8NpKj4c =2MVV -----END PGP SIGNATURE----- --Sig_/k2AhhoIPntp+aTxsAG=dZk/--