memblock: Factor the lowest level alloc function
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/mm/memblock.c b/mm/memblock.c
index 13807f2..e264e8c 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -294,8 +294,8 @@
return (addr + (size - 1)) & ~(size - 1);
}
-static u64 __init memblock_alloc_nid_unreserved(u64 start, u64 end,
- u64 size, u64 align)
+static u64 __init memblock_alloc_region(u64 start, u64 end,
+ u64 size, u64 align)
{
u64 base, res_base;
long j;
@@ -318,6 +318,13 @@
return ~(u64)0;
}
+u64 __weak __init memblock_nid_range(u64 start, u64 end, int *nid)
+{
+ *nid = 0;
+
+ return end;
+}
+
static u64 __init memblock_alloc_nid_region(struct memblock_region *mp,
u64 size, u64 align, int nid)
{
@@ -333,8 +340,7 @@
this_end = memblock_nid_range(start, end, &this_nid);
if (this_nid == nid) {
- u64 ret = memblock_alloc_nid_unreserved(start, this_end,
- size, align);
+ u64 ret = memblock_alloc_region(start, this_end, size, align);
if (ret != ~(u64)0)
return ret;
}
@@ -351,6 +357,10 @@
BUG_ON(0 == size);
+ /* We do a bottom-up search for a region with the right
+ * nid since that's easier considering how memblock_nid_range()
+ * works
+ */
size = memblock_align_up(size, align);
for (i = 0; i < mem->cnt; i++) {
@@ -383,7 +393,7 @@
u64 __init __memblock_alloc_base(u64 size, u64 align, u64 max_addr)
{
- long i, j;
+ long i;
u64 base = 0;
u64 res_base;
@@ -396,33 +406,24 @@
if (max_addr == MEMBLOCK_ALLOC_ANYWHERE)
max_addr = MEMBLOCK_REAL_LIMIT;
+ /* Pump up max_addr */
+ if (max_addr == MEMBLOCK_ALLOC_ANYWHERE)
+ max_addr = ~(u64)0;
+
+ /* We do a top-down search, this tends to limit memory
+ * fragmentation by keeping early boot allocs near the
+ * top of memory
+ */
for (i = memblock.memory.cnt - 1; i >= 0; i--) {
u64 memblockbase = memblock.memory.regions[i].base;
u64 memblocksize = memblock.memory.regions[i].size;
if (memblocksize < size)
continue;
- if (max_addr == MEMBLOCK_ALLOC_ANYWHERE)
- base = memblock_align_down(memblockbase + memblocksize - size, align);
- else if (memblockbase < max_addr) {
- base = min(memblockbase + memblocksize, max_addr);
- base = memblock_align_down(base - size, align);
- } else
- continue;
-
- while (base && memblockbase <= base) {
- j = memblock_overlaps_region(&memblock.reserved, base, size);
- if (j < 0) {
- /* this area isn't reserved, take it */
- if (memblock_add_region(&memblock.reserved, base, size) < 0)
- return 0;
- return base;
- }
- res_base = memblock.reserved.regions[j].base;
- if (res_base < size)
- break;
- base = memblock_align_down(res_base - size, align);
- }
+ base = min(memblockbase + memblocksize, max_addr);
+ res_base = memblock_alloc_region(memblockbase, base, size, align);
+ if (res_base != ~(u64)0)
+ return res_base;
}
return 0;
}
@@ -528,9 +529,3 @@
return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
}
-u64 __weak memblock_nid_range(u64 start, u64 end, int *nid)
-{
- *nid = 0;
-
- return end;
-}