[PATCH] x86-64: Allocate the NUMA hash function nodemap dynamically
Remove the statically allocated memory to NUMA node hash map in favor of a
dynamically allocated memory to node hash map (it is cache aligned).
This patch has the nice side effect in that it allows the hash map to grow
for systems with large amounts of memory (256GB - 1TB), but suffer from
having small PCI space tacked onto the boot node (which is somewhere
between 192MB to 512MB on the ES7000).
Signed-off-by: Amul Shah <amul.shah@unisys.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Rohit Seth <rohitseth@google.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
diff --git a/arch/x86_64/kernel/e820.c b/arch/x86_64/kernel/e820.c
index 6fe191c..9d67955 100644
--- a/arch/x86_64/kernel/e820.c
+++ b/arch/x86_64/kernel/e820.c
@@ -83,6 +83,13 @@
return 1;
}
+#ifdef CONFIG_NUMA
+ /* NUMA memory to node map */
+ if (last >= nodemap_addr && addr < nodemap_addr + nodemap_size) {
+ *addrp = nodemap_addr + nodemap_size;
+ return 1;
+ }
+#endif
/* XXX ramdisk image here? */
return 0;
}
diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c
index 6047724..f330f82 100644
--- a/arch/x86_64/kernel/setup.c
+++ b/arch/x86_64/kernel/setup.c
@@ -444,6 +444,11 @@
/* reserve ebda region */
if (ebda_addr)
reserve_bootmem_generic(ebda_addr, ebda_size);
+#ifdef CONFIG_NUMA
+ /* reserve nodemap region */
+ if (nodemap_addr)
+ reserve_bootmem_generic(nodemap_addr, nodemap_size);
+#endif
#ifdef CONFIG_SMP
/*
diff --git a/arch/x86_64/mm/numa.c b/arch/x86_64/mm/numa.c
index 2ee2e00..7d9c428 100644
--- a/arch/x86_64/mm/numa.c
+++ b/arch/x86_64/mm/numa.c
@@ -36,6 +36,8 @@
cpumask_t node_to_cpumask[MAX_NUMNODES] __read_mostly;
int numa_off __initdata;
+unsigned long __initdata nodemap_addr;
+unsigned long __initdata nodemap_size;
/*
@@ -52,34 +54,87 @@
int res = -1;
unsigned long addr, end;
- if (shift >= 64)
- return -1;
- memset(memnodemap, 0xff, sizeof(memnodemap));
+ memset(memnodemap, 0xff, memnodemapsize);
for (i = 0; i < numnodes; i++) {
addr = nodes[i].start;
end = nodes[i].end;
if (addr >= end)
continue;
- if ((end >> shift) >= NODEMAPSIZE)
+ if ((end >> shift) >= memnodemapsize)
return 0;
do {
if (memnodemap[addr >> shift] != 0xff)
return -1;
memnodemap[addr >> shift] = i;
- addr += (1UL << shift);
+ addr += (1UL << shift);
} while (addr < end);
res = 1;
}
return res;
}
+static int __init allocate_cachealigned_memnodemap(void)
+{
+ unsigned long pad, pad_addr;
+
+ memnodemap = memnode.embedded_map;
+ if (memnodemapsize <= 48) {
+ printk(KERN_DEBUG "NUMA: Allocated memnodemap from %lx - %lx\n",
+ nodemap_addr, nodemap_addr + nodemap_size);
+ return 0;
+ }
+
+ pad = L1_CACHE_BYTES - 1;
+ pad_addr = 0x8000;
+ nodemap_size = pad + memnodemapsize;
+ nodemap_addr = find_e820_area(pad_addr, end_pfn<<PAGE_SHIFT,
+ nodemap_size);
+ if (nodemap_addr == -1UL) {
+ printk(KERN_ERR
+ "NUMA: Unable to allocate Memory to Node hash map\n");
+ nodemap_addr = nodemap_size = 0;
+ return -1;
+ }
+ pad_addr = (nodemap_addr + pad) & ~pad;
+ memnodemap = phys_to_virt(pad_addr);
+
+ printk(KERN_DEBUG "NUMA: Allocated memnodemap from %lx - %lx\n",
+ nodemap_addr, nodemap_addr + nodemap_size);
+ return 0;
+}
+
+/*
+ * The LSB of all start and end addresses in the node map is the value of the
+ * maximum possible shift.
+ */
+static int __init
+extract_lsb_from_nodes (const struct bootnode *nodes, int numnodes)
+{
+ int i;
+ unsigned long start, end;
+ unsigned long bitfield = 0, memtop = 0;
+
+ for (i = 0; i < numnodes; i++) {
+ start = nodes[i].start;
+ end = nodes[i].end;
+ if (start >= end)
+ continue;
+ bitfield |= start | end;
+ if (end > memtop)
+ memtop = end;
+ }
+ i = find_first_bit(&bitfield, sizeof(unsigned long)*8);
+ memnodemapsize = (memtop >> i)+1;
+ return i;
+}
+
int __init compute_hash_shift(struct bootnode *nodes, int numnodes)
{
- int shift = 20;
+ int shift;
- while (populate_memnodemap(nodes, numnodes, shift + 1) >= 0)
- shift++;
-
+ shift = extract_lsb_from_nodes(nodes, numnodes);
+ if (allocate_cachealigned_memnodemap())
+ return -1;
printk(KERN_DEBUG "NUMA: Using %d for the hash shift.\n",
shift);
@@ -290,6 +345,7 @@
end_pfn << PAGE_SHIFT);
/* setup dummy node covering all memory */
memnode_shift = 63;
+ memnodemap = memnode.embedded_map;
memnodemap[0] = 0;
nodes_clear(node_online_map);
node_set_online(0);