On Tue, 2023-08-01 at 10:11 +0530, Aneesh Kumar K.V wrote:
> With memmap on memory, some architecture needs more details w.r.t altmap
> such as base_pfn, end_pfn, etc to unmap vmemmap memory. Instead of
> computing them again when we remove a memory block, embed vmem_altmap
> details in struct memory_block if we are using memmap on memory block
> feature.
>
> Acked-by: David Hildenbrand <david@xxxxxxxxxx>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
> ---
> drivers/base/memory.c | 27 +++++++++++++--------
> include/linux/memory.h | 8 ++----
> mm/memory_hotplug.c | 55 ++++++++++++++++++++++++++----------------
> 3 files changed, 53 insertions(+), 37 deletions(-)
>
<snip>
> @@ -2136,10 +2148,10 @@ EXPORT_SYMBOL(try_offline_node);
>
> static int __ref try_remove_memory(u64 start, u64 size)
> {
> - struct vmem_altmap mhp_altmap = {};
> - struct vmem_altmap *altmap = NULL;
> - unsigned long nr_vmemmap_pages;
> + int ret;
Minor nit - there is already an 'int rc' below - just use that, or
rename it to 'ret' if that's better for consistency.
> + struct memory_block *mem;
> int rc = 0, nid = NUMA_NO_NODE;
> + struct vmem_altmap *altmap = NULL;
>
> BUG_ON(check_hotplug_memory_range(start, size));
>
> @@ -2161,25 +2173,20 @@ static int __ref try_remove_memory(u64 start, u64 size)
> * the same granularity it was added - a single memory block.
> */
> if (mhp_memmap_on_memory()) {
> - nr_vmemmap_pages = walk_memory_blocks(start, size, NULL,
> - get_nr_vmemmap_pages_cb);
> - if (nr_vmemmap_pages) {
> + ret = walk_memory_blocks(start, size, &mem, test_has_altmap_cb);
> + if (ret) {
> if (size != memory_block_size_bytes()) {
> pr_warn("Refuse to remove %#llx - %#llx,"
> "wrong granularity\n",
> start, start + size);
> return -EINVAL;
> }
> -
> + altmap = mem->altmap;
> /*
> - * Let remove_pmd_table->free_hugepage_table do the
> - * right thing if we used vmem_altmap when hot-adding
> - * the range.
> + * Mark altmap NULL so that we can add a debug
> + * check on memblock free.
> */
> - mhp_altmap.base_pfn = PHYS_PFN(start);
> - mhp_altmap.free = nr_vmemmap_pages;
> - mhp_altmap.alloc = nr_vmemmap_pages;
> - altmap = &mhp_altmap;
> + mem->altmap = NULL;
> }
> }
>
