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Diffstat (limited to 'arch/x86/mm/numa_emulation.c')
-rw-r--r--arch/x86/mm/numa_emulation.c107
1 files changed, 87 insertions, 20 deletions
diff --git a/arch/x86/mm/numa_emulation.c b/arch/x86/mm/numa_emulation.c
index 34a2a3bfde9c..b54d52a2d00a 100644
--- a/arch/x86/mm/numa_emulation.c
+++ b/arch/x86/mm/numa_emulation.c
@@ -61,7 +61,7 @@ static int __init emu_setup_memblk(struct numa_meminfo *ei,
eb->nid = nid;
if (emu_nid_to_phys[nid] == NUMA_NO_NODE)
- emu_nid_to_phys[nid] = nid;
+ emu_nid_to_phys[nid] = pb->nid;
pb->start += size;
if (pb->start >= pb->end) {
@@ -198,40 +198,73 @@ static u64 __init find_end_of_node(u64 start, u64 max_addr, u64 size)
return end;
}
+static u64 uniform_size(u64 max_addr, u64 base, u64 hole, int nr_nodes)
+{
+ unsigned long max_pfn = PHYS_PFN(max_addr);
+ unsigned long base_pfn = PHYS_PFN(base);
+ unsigned long hole_pfns = PHYS_PFN(hole);
+
+ return PFN_PHYS((max_pfn - base_pfn - hole_pfns) / nr_nodes);
+}
+
/*
* Sets up fake nodes of `size' interleaved over physical nodes ranging from
* `addr' to `max_addr'.
*
* Returns zero on success or negative on error.
*/
-static int __init split_nodes_size_interleave(struct numa_meminfo *ei,
+static int __init split_nodes_size_interleave_uniform(struct numa_meminfo *ei,
struct numa_meminfo *pi,
- u64 addr, u64 max_addr, u64 size)
+ u64 addr, u64 max_addr, u64 size,
+ int nr_nodes, struct numa_memblk *pblk,
+ int nid)
{
nodemask_t physnode_mask = numa_nodes_parsed;
+ int i, ret, uniform = 0;
u64 min_size;
- int nid = 0;
- int i, ret;
- if (!size)
+ if ((!size && !nr_nodes) || (nr_nodes && !pblk))
return -1;
+
/*
- * The limit on emulated nodes is MAX_NUMNODES, so the size per node is
- * increased accordingly if the requested size is too small. This
- * creates a uniform distribution of node sizes across the entire
- * machine (but not necessarily over physical nodes).
+ * In the 'uniform' case split the passed in physical node by
+ * nr_nodes, in the non-uniform case, ignore the passed in
+ * physical block and try to create nodes of at least size
+ * @size.
+ *
+ * In the uniform case, split the nodes strictly by physical
+ * capacity, i.e. ignore holes. In the non-uniform case account
+ * for holes and treat @size as a minimum floor.
*/
- min_size = (max_addr - addr - mem_hole_size(addr, max_addr)) / MAX_NUMNODES;
- min_size = max(min_size, FAKE_NODE_MIN_SIZE);
- if ((min_size & FAKE_NODE_MIN_HASH_MASK) < min_size)
- min_size = (min_size + FAKE_NODE_MIN_SIZE) &
- FAKE_NODE_MIN_HASH_MASK;
+ if (!nr_nodes)
+ nr_nodes = MAX_NUMNODES;
+ else {
+ nodes_clear(physnode_mask);
+ node_set(pblk->nid, physnode_mask);
+ uniform = 1;
+ }
+
+ if (uniform) {
+ min_size = uniform_size(max_addr, addr, 0, nr_nodes);
+ size = min_size;
+ } else {
+ /*
+ * The limit on emulated nodes is MAX_NUMNODES, so the
+ * size per node is increased accordingly if the
+ * requested size is too small. This creates a uniform
+ * distribution of node sizes across the entire machine
+ * (but not necessarily over physical nodes).
+ */
+ min_size = uniform_size(max_addr, addr,
+ mem_hole_size(addr, max_addr), nr_nodes);
+ }
+ min_size = ALIGN(max(min_size, FAKE_NODE_MIN_SIZE), FAKE_NODE_MIN_SIZE);
if (size < min_size) {
pr_err("Fake node size %LuMB too small, increasing to %LuMB\n",
size >> 20, min_size >> 20);
size = min_size;
}
- size &= FAKE_NODE_MIN_HASH_MASK;
+ size = ALIGN_DOWN(size, FAKE_NODE_MIN_SIZE);
/*
* Fill physical nodes with fake nodes of size until there is no memory
@@ -248,10 +281,14 @@ static int __init split_nodes_size_interleave(struct numa_meminfo *ei,
node_clear(i, physnode_mask);
continue;
}
+
start = pi->blk[phys_blk].start;
limit = pi->blk[phys_blk].end;
- end = find_end_of_node(start, limit, size);
+ if (uniform)
+ end = start + size;
+ else
+ end = find_end_of_node(start, limit, size);
/*
* If there won't be at least FAKE_NODE_MIN_SIZE of
* non-reserved memory in ZONE_DMA32 for the next node,
@@ -266,7 +303,8 @@ static int __init split_nodes_size_interleave(struct numa_meminfo *ei,
* next node, this one must extend to the end of the
* physical node.
*/
- if (limit - end - mem_hole_size(end, limit) < size)
+ if ((limit - end - mem_hole_size(end, limit) < size)
+ && !uniform)
end = limit;
ret = emu_setup_memblk(ei, pi, nid++ % MAX_NUMNODES,
@@ -276,7 +314,15 @@ static int __init split_nodes_size_interleave(struct numa_meminfo *ei,
return ret;
}
}
- return 0;
+ return nid;
+}
+
+static int __init split_nodes_size_interleave(struct numa_meminfo *ei,
+ struct numa_meminfo *pi,
+ u64 addr, u64 max_addr, u64 size)
+{
+ return split_nodes_size_interleave_uniform(ei, pi, addr, max_addr, size,
+ 0, NULL, NUMA_NO_NODE);
}
int __init setup_emu2phys_nid(int *dfl_phys_nid)
@@ -346,7 +392,28 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt)
* the fixed node size. Otherwise, if it is just a single number N,
* split the system RAM into N fake nodes.
*/
- if (strchr(emu_cmdline, 'M') || strchr(emu_cmdline, 'G')) {
+ if (strchr(emu_cmdline, 'U')) {
+ nodemask_t physnode_mask = numa_nodes_parsed;
+ unsigned long n;
+ int nid = 0;
+
+ n = simple_strtoul(emu_cmdline, &emu_cmdline, 0);
+ ret = -1;
+ for_each_node_mask(i, physnode_mask) {
+ ret = split_nodes_size_interleave_uniform(&ei, &pi,
+ pi.blk[i].start, pi.blk[i].end, 0,
+ n, &pi.blk[i], nid);
+ if (ret < 0)
+ break;
+ if (ret < n) {
+ pr_info("%s: phys: %d only got %d of %ld nodes, failing\n",
+ __func__, i, ret, n);
+ ret = -1;
+ break;
+ }
+ nid = ret;
+ }
+ } else if (strchr(emu_cmdline, 'M') || strchr(emu_cmdline, 'G')) {
u64 size;
size = memparse(emu_cmdline, &emu_cmdline);