David Hildenbrand <david@xxxxxxxxxx> writes:
> There is only a single user remaining. We can simply try to offline all
> online nodes - which is fast, because we usually span pages and can skip
> such nodes right away.
That makes me slightly nervous, because our big powerpc boxes tend to
trip on these scaling issues before others.
But the spanned pages check is just:
void try_offline_node(int nid)
{
pg_data_t *pgdat = NODE_DATA(nid);
...
if (pgdat->node_spanned_pages)
return;
So I guess that's pretty cheap, and it's only O(nodes), which should
never get that big.
> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
> Cc: Paul Mackerras <paulus@xxxxxxxxx>
> Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
> Cc: Len Brown <lenb@xxxxxxxxxx>
> Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
> Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx>
> Cc: Dave Jiang <dave.jiang@xxxxxxxxx>
> Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx>
> Cc: Jason Wang <jasowang@xxxxxxxxxx>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Nathan Lynch <nathanl@xxxxxxxxxxxxx>
> Cc: Laurent Dufour <ldufour@xxxxxxxxxxxxx>
> Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx>
> Cc: Scott Cheloha <cheloha@xxxxxxxxxxxxx>
> Cc: Anton Blanchard <anton@xxxxxxxxxx>
> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
> Cc: linux-acpi@xxxxxxxxxxxxxxx
> Cc: nvdimm@xxxxxxxxxxxxxxx
> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
> ---
> .../platforms/pseries/hotplug-memory.c | 9 ++++-----
> drivers/acpi/acpi_memhotplug.c | 7 +------
> drivers/dax/kmem.c | 3 +--
> drivers/virtio/virtio_mem.c | 4 ++--
> include/linux/memory_hotplug.h | 10 +++++-----
> mm/memory_hotplug.c | 20 +++++++++----------
> 6 files changed, 23 insertions(+), 30 deletions(-)
>
> diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c
> index 8377f1f7c78e..4a9232ddbefe 100644
> --- a/arch/powerpc/platforms/pseries/hotplug-memory.c
> +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
> @@ -286,7 +286,7 @@ static int pseries_remove_memblock(unsigned long base, unsigned long memblock_si
> {
> unsigned long block_sz, start_pfn;
> int sections_per_block;
> - int i, nid;
> + int i;
>
> start_pfn = base >> PAGE_SHIFT;
>
> @@ -297,10 +297,9 @@ static int pseries_remove_memblock(unsigned long base, unsigned long memblock_si
>
> block_sz = pseries_memory_block_size();
> sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
> - nid = memory_add_physaddr_to_nid(base);
>
> for (i = 0; i < sections_per_block; i++) {
> - __remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE);
> + __remove_memory(base, MIN_MEMORY_BLOCK_SIZE);
> base += MIN_MEMORY_BLOCK_SIZE;
> }
>
> @@ -386,7 +385,7 @@ static int dlpar_remove_lmb(struct drmem_lmb *lmb)
>
> block_sz = pseries_memory_block_size();
>
> - __remove_memory(mem_block->nid, lmb->base_addr, block_sz);
> + __remove_memory(lmb->base_addr, block_sz);
> put_device(&mem_block->dev);
>
> /* Update memory regions for memory remove */
> @@ -638,7 +637,7 @@ static int dlpar_add_lmb(struct drmem_lmb *lmb)
>
> rc = dlpar_online_lmb(lmb);
> if (rc) {
> - __remove_memory(nid, lmb->base_addr, block_sz);
> + __remove_memory(lmb->base_addr, block_sz);
> invalidate_lmb_associativity_index(lmb);
> } else {
> lmb->flags |= DRCONF_MEM_ASSIGNED;
Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> (powerpc)
cheers
