From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH RT] ehea: make receive irq handler non-threaded (IRQF_NODELAY) From: Michael Ellerman To: Thomas Gleixner In-Reply-To: References: <4BF30793.5070300@us.ibm.com> <4BF30C32.1020403@linux.vnet.ibm.com> <4BF31322.5090206@us.ibm.com> <1274232324.29980.9.camel@concordia> <4BF3F2DB.7030701@us.ibm.com> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-aiq25ZM3gW5ZVbBYYhS/" Date: Thu, 20 May 2010 11:34:08 +1000 Message-ID: <1274319248.22892.40.camel@concordia> Mime-Version: 1.0 Cc: Darren Hart , Jan-Bernd Themann , dvhltc@linux.vnet.ibm.com, linux-kernel@vger.kernel.org, Will Schmidt , Brian King , niv@linux.vnet.ibm.com, Doug Maxey , linuxppc-dev@lists.ozlabs.org Reply-To: michael@ellerman.id.au List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --=-aiq25ZM3gW5ZVbBYYhS/ Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, 2010-05-19 at 23:08 +0200, Thomas Gleixner wrote: > On Wed, 19 May 2010, Thomas Gleixner wrote: > > > I'm still not clear on why the ultimate solution wasn't to have XICS = report > > > edge triggered as edge triggered. Probably some complexity of the ent= ire power > > > stack that I am ignorant of. > > >=20 > > > > Apart from the issue of loosing interrupts there is also the fact t= hat > > > > masking on the XICS requires an RTAS call which takes a global lock= . > >=20 > > Right, I'd love to avoid that but with real level interrupts we'd run > > into an interrupt storm. Though another solution would be to issue the > > EOI after the threaded handler finished, that'd work as well, but > > needs testing. >=20 > Thought more about that. The case at hand (ehea) is nasty: >=20 > The driver does _NOT_ disable the rx interrupt in the card in the rx > interrupt handler - for whatever reason. Yeah I saw that, but I don't know why it's written that way. Perhaps Jan-Bernd or Doug will chime in and enlighten us? :) cheers --=-aiq25ZM3gW5ZVbBYYhS/ Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iEYEABECAAYFAkv0kZAACgkQdSjSd0sB4dIFugCgjix5AnNDseOZh2iuTLfFEzMy 4SMAn0qUvgVBUVw7mrFFEzN1/4aSzJnZ =9YxJ -----END PGP SIGNATURE----- --=-aiq25ZM3gW5ZVbBYYhS/--