From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: [PATCH V3] xen/balloon: Memory hotplug support for Xen balloon driver Date: Wed, 18 May 2011 08:21:49 +0100 Message-ID: <1305703309.7738.23.camel@dagon.hellion.org.uk> References: <20110517214421.GD30232@router-fw-old.local.net-space.pl> <1305701868.28175.1.camel@vase> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1305701868.28175.1.camel@vase> Sender: owner-linux-mm@kvack.org To: "v.tolstov@selfip.ru" Cc: Daniel Kiper , "akpm@linux-foundation.org" , "andi.kleen@intel.com" , "haicheng.li@linux.intel.com" , "fengguang.wu@intel.com" , "jeremy@goop.org" , "konrad.wilk@oracle.com" , Dan Magenheimer , "pasik@iki.fi" , "dave@linux.vnet.ibm.com" , "wdauchy@gmail.com" , "rientjes@google.com" , "xen-devel@lists.xensource.com" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" List-Id: xen-devel@lists.xenproject.org On Wed, 2011-05-18 at 07:57 +0100, Vasiliy G Tolstov wrote: > On Tue, 2011-05-17 at 23:44 +0200, Daniel Kiper wrote: > > + Memory could be hotplugged in following steps: > > + > > + 1) dom0: xl mem-max > > + where is >= requested memory size, > > + > > + 2) dom0: xl mem-set > > + where is requested memory size; alternatively memory > > + could be added by writing proper value to > > + /sys/devices/system/xen_memory/xen_memory0/target or > > + /sys/devices/system/xen_memory/xen_memory0/target_kb on dumU, > > + > > + 3) domU: for i in /sys/devices/system/memory/memory*/state; do \ > > + [ "`cat "$i"`" = offline ] && echo online > "$i"; done > > + > Very good. Is that possible to eliminate step 3 ? And do it automatic if > domU runs with specific xen balloon param? When we faced the same question WRT VCPU hotplug we ended up using a udev rule. Presumably the same could be done here. In the VCPU case the rule is: ACTION=="add", SUBSYSTEM=="cpu", RUN+="/bin/sh -c '[ ! -e /sys$devpath/online ] || echo 1 > /sys$devpath/online'" Presumably the memory one will be broadly similar. Ian. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org