> +/**
> + * for_each_free_mem_range_in_zone - iterate through zone specific free
> + * memblock areas
> + * @i: u64 used as loop variable
> + * @zone: zone in which all of the memory blocks reside
> + * @p_start: ptr to phys_addr_t for start address of the range, can be %NULL
> + * @p_end: ptr to phys_addr_t for end address of the range, can be %NULL
> + *
> + * Walks over free (memory && !reserved) areas of memblock in a specific
> + * zone. Available as soon as memblock is initialized.
> + */
> +#define for_each_free_mem_pfn_range_in_zone(i, zone, p_start, p_end) \
> + for (i = 0, \
> + __next_mem_pfn_range_in_zone(&i, zone, p_start, p_end); \
> + i != (u64)ULLONG_MAX; \
> + __next_mem_pfn_range_in_zone(&i, zone, p_start, p_end))
> +#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
Use U64_MAX instead of ULLONG_MAX, and avoid u64 cast. I know other
places in this file use UULONG_MAX with cast, but I think U64_MAX is
better.
> +
> /**
> * for_each_free_mem_range - iterate through free memblock areas
> * @i: u64 used as loop variable
> diff --git a/mm/memblock.c b/mm/memblock.c
> index 7df468c8ebc8..f1d1fbfd1ae7 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -1239,6 +1239,69 @@ int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
> return 0;
> }
> #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
> +#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
> +/**
> + * __next_mem_pfn_range_in_zone - iterator for for_each_*_range_in_zone()
> + *
> + * @idx: pointer to u64 loop variable
> + * @zone: zone in which all of the memory blocks reside
> + * @out_start: ptr to ulong for start pfn of the range, can be %NULL
> + * @out_end: ptr to ulong for end pfn of the range, can be %NULL
> + *
> + * This function is meant to be a zone/pfn specific wrapper for the
> + * for_each_mem_range type iterators. Specifically they are used in the
> + * deferred memory init routines and as such we were duplicating much of
> + * this logic throughout the code. So instead of having it in multiple
> + * locations it seemed like it would make more sense to centralize this to
> + * one new iterator that does everything they need.
> + */
> +void __init_memblock
> +__next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone,
> + unsigned long *out_spfn, unsigned long *out_epfn)
> +{
> + int zone_nid = zone_to_nid(zone);
> + phys_addr_t spa, epa;
> + int nid;
> +
> + __next_mem_range(idx, zone_nid, MEMBLOCK_NONE,
> + &memblock.memory, &memblock.reserved,
> + &spa, &epa, &nid);
> +
> + while (*idx != ULLONG_MAX) {
Ditto, use U64_MAX
> + unsigned long epfn = PFN_DOWN(epa);
> + unsigned long spfn = PFN_UP(spa);
> +
> + /*
> + * Verify the end is at least past the start of the zone and
> + * that we have at least one PFN to initialize.
> + */
> + if (zone->zone_start_pfn < epfn && spfn < epfn) {
> + /* if we went too far just stop searching */
> + if (zone_end_pfn(zone) <= spfn)
> + break;
Set *idx = U64_MAX here, then break. This way after we are outside this
while loop idx is always equals to U64_MAX.
> +
> + if (out_spfn)
> + *out_spfn = max(zone->zone_start_pfn, spfn);
> + if (out_epfn)
> + *out_epfn = min(zone_end_pfn(zone), epfn);
Don't we need to verify after adjustment that out_spfn != out_epfn, so
there is at least one PFN to initialize?
The rest looks good. Once the above is fixed:
Reviewed-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Thank you,
Pasha
