@@ -48,5 +48,29 @@ ulong __init_memblock memblock_next_valid_pfn(ulong pfn)
return PHYS_PFN(regions[early_region_idx].base);
}
EXPORT_SYMBOL(memblock_next_valid_pfn);
+
+int pfn_valid_region(ulong pfn)
+{
+ ulong start_pfn, end_pfn;
+ struct memblock_type *type = &memblock.memory;
+ struct memblock_region *regions = type->regions;
+
+ if (early_region_idx != -1) {
+ start_pfn = PFN_DOWN(regions[early_region_idx].base);
+ end_pfn = PFN_DOWN(regions[early_region_idx].base +
+ regions[early_region_idx].size);
+
+ if (pfn >= start_pfn && pfn < end_pfn)
+ return !memblock_is_nomap(
+ ®ions[early_region_idx]);
+ }
+
+ early_region_idx = memblock_search_pfn_regions(pfn);
+ if (early_region_idx == -1)
+ return false;
+
+ return !memblock_is_nomap(®ions[early_region_idx]);
+}
+EXPORT_SYMBOL(pfn_valid_region);
#endif /*CONFIG_HAVE_ARCH_PFN_VALID*/
#endif /*__ARM96_COMMON_H*/
Commit b92df1de5d28 ("mm: page_alloc: skip over regions of invalid pfns where possible") optimized the loop in memmap_init_zone(). But there is still some room for improvement. E.g. in early_pfn_valid(), if pfn and pfn+1 are in the same memblock region, we can record the last returned memblock region index and check pfn++ is still in the same region. Thus we can avoid do the slow binary searches. Currently it only improve the performance on arm/arm64 and will have no impact on other arches. Signed-off-by: Jia He <jia.he@hxt-semitech.com> --- include/linux/arm96_common.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+)