Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755205AbZJZH66 (ORCPT ); Mon, 26 Oct 2009 03:58:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755123AbZJZH65 (ORCPT ); Mon, 26 Oct 2009 03:58:57 -0400 Received: from xc.sipsolutions.net ([83.246.72.84]:35420 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754995AbZJZH64 (ORCPT ); Mon, 26 Oct 2009 03:58:56 -0400 Subject: Re: [PATCH] net: Adjust softirq raising in __napi_schedule From: Johannes Berg To: Jarek Poplawski Cc: Tilman Schmidt , David Miller , hidave.darkstar@gmail.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, linux-wireless@vger.kernel.org, linux-ppp@vger.kernel.org, netdev@vger.kernel.org, paulus@samba.org, Michael Buesch , Oliver Hartkopp In-Reply-To: <20091026075438.GB6187@ff.dom.local> References: <4AD76184.6030900@gmail.com> <4ADF5710.4030505@imap.cc> <20091021211906.GA11401@ami.dom.local> <1256160330.12174.2.camel@johannes.local> <20091021213947.GA12202@ami.dom.local> <1256200021.12174.11.camel@johannes.local> <4AE1C00B.5010008@imap.cc> <1256309191.12174.51.camel@johannes.local> <20091026074126.GA6187@ff.dom.local> <1256543054.28230.6.camel@johannes.local> <20091026075438.GB6187@ff.dom.local> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-5UamH4+2+8z4jInfScvN" Date: Mon, 26 Oct 2009 08:58:52 +0100 Message-ID: <1256543932.28230.9.camel@johannes.local> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2085 Lines: 54 --=-5UamH4+2+8z4jInfScvN Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, 2009-10-26 at 07:54 +0000, Jarek Poplawski wrote: > > No, I wrote that I didn't know. I suppose now that I looked at it I do > > know, and only disabling preemption is required. >=20 > But netif_rx has preemption disabled most of the time (by hardirqs > disabling). So maybe disabling preemption isn't the main reason here > either? Not for netpoll though, which may or may not be relevant (if I were to venture a guess I'd say it isn't and it disables preemption to be able to do the softirq thing) However, I lost track now of why we're discussing this. Basically it boils down to using netif_rx() when in (soft)irq, and netif_rx_ni() when in process context. That could just be an optimisation, but it's a very valid one. johannes --=-5UamH4+2+8z4jInfScvN Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- iQIcBAABAgAGBQJK5Va4AAoJEODzc/N7+QmaGZ0P/3XWgEgM6SCQX98BVmafmXc5 2Mbi7bpGvxC34SPawy9T3H7vUgRrATm8S/DGDscgRjTAY0/bZQaau2dFs+a2UBfc 4XJvc41om+OuhG83o9LvyjlGN1w0XFt8WwPFT7UeXoRRePnXz0DPt3YPMiZ9IkwY tynu6L3i2yG+G2xR2/rd49Dk15YZJfKzbJs6KrMJhtOWPYMWXrDfXD2CDUApbXOZ 3tzaZrnRF/YbBLvOlNrxoRyBhQyvR+QgiKdnQkf5dD+DqAtPVdFPrJHRdp/W9m1p Dgqvml35IoWNA71BeDdH+ozEGkLLESp7G8nR1nnZpU2IBR5PhuPfAzfb6t763bW3 qS57TUtAGcokPm+HonmginKt2q34+nN3J+iRyjr0XIRlcm05idvMImxBucVYf6CF cbVMZ5BGwZRvjj6e2YOdNRZRbcy+5sNfCRF+AGYWuDyF9WbEiaecKnAx0qkWcRQv BLTDC35t5cS5M4+Qa/cyopFc9uvBxGa1gMUYpqmSqV6Ix24bdzZlM+e9FrTprsud 3L/9XjrA8daRU1DQzaAz0uWAL07gu0xq6kJpBndFsDcTq4HIKJvEERvF4fGogURu ENDJ6UgqWDMsnIzmVFsOTeZv0YggzRwIc6AxUoSwdHSwSJtszlknjN9Yhzxvw2AR Wh1lCuj79evprgY5Fhsx =NWhK -----END PGP SIGNATURE----- --=-5UamH4+2+8z4jInfScvN-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/