From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Phillips Subject: Re: [RFC][PATCH 0/9] Network receive deadlock prevention for NBD Date: Sun, 13 Aug 2006 17:56:08 -0700 Message-ID: <44DFCA28.7040808@google.com> References: <1155127040.12225.25.camel@twins> <20060809130752.GA17953@2ka.mipt.ru> <1155130353.12225.53.camel@twins> <44DD4E3A.4040000@redhat.com> <20060812084713.GA29523@2ka.mipt.ru> <1155374390.13508.15.camel@lappy> <20060812093706.GA13554@2ka.mipt.ru> <44DDE857.3080703@redhat.com> <20060812144921.GA25058@2ka.mipt.ru> <44DDEC1F.6010603@redhat.com> <20060812150842.GA5638@2ka.mipt.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=KOI8-R; format=flowed Content-Transfer-Encoding: 7bit Cc: Rik van Riel , Peter Zijlstra , linux-mm@kvack.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Return-path: Received: from smtp-out.google.com ([216.239.45.12]:16040 "EHLO smtp-out.google.com") by vger.kernel.org with ESMTP id S1751177AbWHNA4Z (ORCPT ); Sun, 13 Aug 2006 20:56:25 -0400 To: Evgeniy Polyakov In-Reply-To: <20060812150842.GA5638@2ka.mipt.ru> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Evgeniy Polyakov wrote: > One must receive a packet to determine if that packet must be dropped > until tricky hardware with header split capabilities or MMIO copying is > used. Peter uses special pool to get data from when system is in OOM (at > least in his latest patchset), so allocations are separated and thus > network code is not affected by OOM condition, which allows to make > forward progress. Nice executive summary. Crucial point: you want to say "in reclaim" not "in OOM". Yes, right from the beginning the patch set got its sk_buff memory from a special pool when the system is in reclaim, however the exact nature of the pool and how/where it is accounted has evolved... mostly forward. Regards, Daniel