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From: KAMEZAWA Hiroyuki on 25 Feb 2010 20:20 On Thu, 25 Feb 2010 12:30:26 -0600 (CST) Christoph Lameter <cl(a)linux-foundation.org> wrote: > On Thu, 25 Feb 2010, David Rientjes wrote: > > > I don't see how memory hotadd with a new node being onlined could have > > worked fine before since slab lacked any memory hotplug notifier until > > Andi just added it. > > AFAICR The cpu notifier took on that role in the past. > > If what you say is true then memory hotplug has never worked before. > Kamesan? > In this code, int node = numa_node_id(); node is got by its CPU. At node hotplug, following order should be kept. Add: memory -> cpu Remove: cpu -> memory cpus must be onlined after memory. At least, we online cpus only after memory. Then, we(our heavy test on RHEL5) never see this kind of race. I'm sorry if my answer misses your point. Thanks, -Kame > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo(a)vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Pekka Enberg on 26 Feb 2010 05:50 Christoph Lameter kirjoitti: >> kmalloc_node() in generic kernel code. All that is done under >> MEM_GOING_ONLINE and not MEM_ONLINE, which is why I suggest the first and >> fourth patch in this series may not be necessary if we prevent setting the >> bit in the nodemask or building the zonelists until the slab nodelists are >> ready. > > That sounds good. Andi? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Andi Kleen on 26 Feb 2010 06:50 On Thu, Feb 25, 2010 at 12:30:26PM -0600, Christoph Lameter wrote: > On Thu, 25 Feb 2010, David Rientjes wrote: > > > I don't see how memory hotadd with a new node being onlined could have > > worked fine before since slab lacked any memory hotplug notifier until > > Andi just added it. > > AFAICR The cpu notifier took on that role in the past. The problem is that slab already allocates inside the notifier and then some state wasn't set up. > If what you say is true then memory hotplug has never worked before. > Kamesan? Memory hotplug with node add never quite worked on x86 before, for various reasons not related to slab. -Andi -- ak(a)linux.intel.com -- Speaking for myself only. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Andi Kleen on 26 Feb 2010 06:50 On Fri, Feb 26, 2010 at 12:45:02PM +0200, Pekka Enberg wrote: > Christoph Lameter kirjoitti: >>> kmalloc_node() in generic kernel code. All that is done under >>> MEM_GOING_ONLINE and not MEM_ONLINE, which is why I suggest the first and >>> fourth patch in this series may not be necessary if we prevent setting the >>> bit in the nodemask or building the zonelists until the slab nodelists are >>> ready. >> >> That sounds good. > > Andi? Well if Christoph wants to submit a better patch that is tested and solves the problems he can do that. if he doesn't then I think my patch kit which has been tested is the best alternative currently. -Andi -- ak(a)linux.intel.com -- Speaking for myself only. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Pekka Enberg on 26 Feb 2010 07:40
On Fri, Feb 26, 2010 at 1:43 PM, Andi Kleen <andi(a)firstfloor.org> wrote: > On Fri, Feb 26, 2010 at 12:45:02PM +0200, Pekka Enberg wrote: >> Christoph Lameter kirjoitti: >>>> kmalloc_node() in generic kernel code. �All that is done under >>>> MEM_GOING_ONLINE and not MEM_ONLINE, which is why I suggest the first and >>>> fourth patch in this series may not be necessary if we prevent setting the >>>> bit in the nodemask or building the zonelists until the slab nodelists are >>>> ready. >>> >>> That sounds good. >> >> Andi? > > Well if Christoph wants to submit a better patch that is tested and solves > the problems he can do that. Sure. > if he doesn't then I think my patch kit which has been tested > is the best alternative currently. So do you expect me to merge your patches over his objections? Pekka -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |