Re: [PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-10-04 Thread Reza Arbab
On Tue, Oct 04, 2016 at 11:48:30AM +1100, Balbir Singh wrote: On 27/09/16 10:14, Reza Arbab wrote: Right. To be clear, the background info I put in the commit log refers to x86, where the SRAT can describe movable nodes which exist at boot. They're trying to avoid allocations from those nodes

Re: [PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-10-04 Thread Reza Arbab
On Tue, Oct 04, 2016 at 11:48:30AM +1100, Balbir Singh wrote: On 27/09/16 10:14, Reza Arbab wrote: Right. To be clear, the background info I put in the commit log refers to x86, where the SRAT can describe movable nodes which exist at boot. They're trying to avoid allocations from those nodes

Re: [PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-10-03 Thread Balbir Singh
On 27/09/16 10:14, Reza Arbab wrote: > On Tue, Sep 27, 2016 at 07:12:31AM +1000, Benjamin Herrenschmidt wrote: >> In any case, if the memory hasn't been hotplug, this shouldn't be necessary >> as we shouldn't be considering it for allocation. > > Right. To be clear, the background info I put

Re: [PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-10-03 Thread Balbir Singh
On 27/09/16 10:14, Reza Arbab wrote: > On Tue, Sep 27, 2016 at 07:12:31AM +1000, Benjamin Herrenschmidt wrote: >> In any case, if the memory hasn't been hotplug, this shouldn't be necessary >> as we shouldn't be considering it for allocation. > > Right. To be clear, the background info I put

Re: [PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-09-26 Thread Reza Arbab
On Tue, Sep 27, 2016 at 07:12:31AM +1000, Benjamin Herrenschmidt wrote: In any case, if the memory hasn't been hotplug, this shouldn't be necessary as we shouldn't be considering it for allocation. Right. To be clear, the background info I put in the commit log refers to x86, where the SRAT

Re: [PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-09-26 Thread Reza Arbab
On Tue, Sep 27, 2016 at 07:12:31AM +1000, Benjamin Herrenschmidt wrote: In any case, if the memory hasn't been hotplug, this shouldn't be necessary as we shouldn't be considering it for allocation. Right. To be clear, the background info I put in the commit log refers to x86, where the SRAT

Re: [PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-09-26 Thread Benjamin Herrenschmidt
On Sun, 2016-09-25 at 13:36 -0500, Reza Arbab wrote: > At boot, the movable_node option sets bottom-up memblock allocation. > > This reduces the chance that, in the window before movable memory has > been identified, an allocation for the kernel might come from a movable > node. By going

Re: [PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-09-26 Thread Benjamin Herrenschmidt
On Sun, 2016-09-25 at 13:36 -0500, Reza Arbab wrote: > At boot, the movable_node option sets bottom-up memblock allocation. > > This reduces the chance that, in the window before movable memory has > been identified, an allocation for the kernel might come from a movable > node. By going

Re: [PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-09-26 Thread Reza Arbab
On Mon, Sep 26, 2016 at 09:17:43PM +0530, Aneesh Kumar K.V wrote: + /* bottom-up allocation may have been set by movable_node */ + memblock_set_bottom_up(false); + By then we have done few memblock allocation right ? Yes, some allocations do occur while bottom-up is set. IMHO,

Re: [PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-09-26 Thread Reza Arbab
On Mon, Sep 26, 2016 at 09:17:43PM +0530, Aneesh Kumar K.V wrote: + /* bottom-up allocation may have been set by movable_node */ + memblock_set_bottom_up(false); + By then we have done few memblock allocation right ? Yes, some allocations do occur while bottom-up is set. IMHO,

Re: [PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-09-26 Thread Aneesh Kumar K.V
Reza Arbab writes: > At boot, the movable_node option sets bottom-up memblock allocation. > > This reduces the chance that, in the window before movable memory has > been identified, an allocation for the kernel might come from a movable > node. By going bottom-up,

Re: [PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-09-26 Thread Aneesh Kumar K.V
Reza Arbab writes: > At boot, the movable_node option sets bottom-up memblock allocation. > > This reduces the chance that, in the window before movable memory has > been identified, an allocation for the kernel might come from a movable > node. By going bottom-up, early allocations will most

[PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-09-25 Thread Reza Arbab
At boot, the movable_node option sets bottom-up memblock allocation. This reduces the chance that, in the window before movable memory has been identified, an allocation for the kernel might come from a movable node. By going bottom-up, early allocations will most likely come from the same node

[PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

2016-09-25 Thread Reza Arbab
At boot, the movable_node option sets bottom-up memblock allocation. This reduces the chance that, in the window before movable memory has been identified, an allocation for the kernel might come from a movable node. By going bottom-up, early allocations will most likely come from the same node