[PATCH 31/43] memblock: Add arch function to control coalescing of memblock memory regions
in [Kernel]
|
Prev: [PATCH 08/43] memblock/microblaze: Use new accessors
Next: [PATCH 10/43] memblock/sparc: Use new accessors
From: Benjamin Herrenschmidt on 6 Aug 2010 01:30 Some archs such as ARM want to avoid coalescing accross things such as the lowmem/highmem boundary or similar. This provides the option to control it via an arch callback for which a weak default is provided which always allows coalescing. Signed-off-by: Benjamin Herrenschmidt <benh(a)kernel.crashing.org> --- include/linux/memblock.h | 2 ++ mm/memblock.c | 19 ++++++++++++++++++- 2 files changed, 20 insertions(+), 1 deletions(-) diff --git a/include/linux/memblock.h b/include/linux/memblock.h index 150be93..e5e8f9d 100644 --- a/include/linux/memblock.h +++ b/include/linux/memblock.h @@ -72,6 +72,8 @@ extern void memblock_dump_all(void); /* Provided by the architecture */ extern phys_addr_t memblock_nid_range(phys_addr_t start, phys_addr_t end, int *nid); +extern int memblock_memory_can_coalesce(phys_addr_t addr1, phys_addr_t size1, + phys_addr_t addr2, phys_addr_t size2); /** * memblock_set_current_limit - Set the current allocation limit to allow diff --git a/mm/memblock.c b/mm/memblock.c index 0787790..8715f09 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -241,6 +241,12 @@ static int memblock_double_array(struct memblock_type *type) return 0; } +extern int __weak memblock_memory_can_coalesce(phys_addr_t addr1, phys_addr_t size1, + phys_addr_t addr2, phys_addr_t size2) +{ + return 1; +} + static long memblock_add_region(struct memblock_type *type, phys_addr_t base, phys_addr_t size) { unsigned long coalesced = 0; @@ -262,6 +268,10 @@ static long memblock_add_region(struct memblock_type *type, phys_addr_t base, ph return 0; adjacent = memblock_addrs_adjacent(base, size, rgnbase, rgnsize); + /* Check if arch allows coalescing */ + if (adjacent != 0 && type == &memblock.memory && + !memblock_memory_can_coalesce(base, size, rgnbase, rgnsize)) + break; if (adjacent > 0) { type->regions[i].base -= size; type->regions[i].size += size; @@ -274,7 +284,14 @@ static long memblock_add_region(struct memblock_type *type, phys_addr_t base, ph } } - if ((i < type->cnt - 1) && memblock_regions_adjacent(type, i, i+1)) { + /* If we plugged a hole, we may want to also coalesce with the + * next region + */ + if ((i < type->cnt - 1) && memblock_regions_adjacent(type, i, i+1) && + ((type != &memblock.memory || memblock_memory_can_coalesce(type->regions[i].base, + type->regions[i].size, + type->regions[i+1].base, + type->regions[i+1].size)))) { memblock_coalesce_regions(type, i, i+1); coalesced++; } -- 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |