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This change can save 8 * u64 entries per CMA. Signed-off-by: Zhongkun He --- mm/cma.c | 11 ++++++----- mm/cma.h | 6 ++++-- 2 files changed, 10 insertions(+), 7 deletions(-) diff --git a/mm/cma.c b/mm/cma.c index 15632939f20a..ec4b9a401b7d 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -143,13 +143,14 @@ bool cma_validate_zones(struct cma *cma) =20 static void __init cma_activate_area(struct cma *cma) { - unsigned long pfn, end_pfn; + unsigned long pfn, end_pfn, early_pfn[CMA_MAX_RANGES]; int allocrange, r; struct cma_memrange *cmr; unsigned long bitmap_count, count; =20 for (allocrange =3D 0; allocrange < cma->nranges; allocrange++) { cmr =3D &cma->ranges[allocrange]; + early_pfn[allocrange] =3D cmr->early_pfn; cmr->bitmap =3D bitmap_zalloc(cma_bitmap_maxno(cma, cmr), GFP_KERNEL); if (!cmr->bitmap) @@ -161,13 +162,13 @@ static void __init cma_activate_area(struct cma *cma) =20 for (r =3D 0; r < cma->nranges; r++) { cmr =3D &cma->ranges[r]; - if (cmr->early_pfn !=3D cmr->base_pfn) { - count =3D cmr->early_pfn - cmr->base_pfn; + if (early_pfn[r] !=3D cmr->base_pfn) { + count =3D early_pfn[r] - cmr->base_pfn; bitmap_count =3D cma_bitmap_pages_to_bits(cma, count); bitmap_set(cmr->bitmap, 0, bitmap_count); } =20 - for (pfn =3D cmr->early_pfn; pfn < cmr->base_pfn + cmr->count; + for (pfn =3D early_pfn[r]; pfn < cmr->base_pfn + cmr->count; pfn +=3D pageblock_nr_pages) init_cma_reserved_pageblock(pfn_to_page(pfn)); } @@ -193,7 +194,7 @@ static void __init cma_activate_area(struct cma *cma) for (r =3D 0; r < allocrange; r++) { cmr =3D &cma->ranges[r]; end_pfn =3D cmr->base_pfn + cmr->count; - for (pfn =3D cmr->early_pfn; pfn < end_pfn; pfn++) + for (pfn =3D early_pfn[r]; pfn < end_pfn; pfn++) free_reserved_page(pfn_to_page(pfn)); } } diff --git a/mm/cma.h b/mm/cma.h index 41a3ab0ec3de..c70180c36559 100644 --- a/mm/cma.h +++ b/mm/cma.h @@ -25,9 +25,11 @@ struct cma_kobject { */ struct cma_memrange { unsigned long base_pfn; - unsigned long early_pfn; unsigned long count; - unsigned long *bitmap; + union { + unsigned long early_pfn; + unsigned long *bitmap; + }; #ifdef CONFIG_CMA_DEBUGFS struct debugfs_u32_array dfs_bitmap; #endif --=20 2.39.5