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-rw-r--r--Documentation/x86/x86_64/boot-options.txt4
-rw-r--r--arch/x86/include/asm/mmzone_64.h6
-rw-r--r--arch/x86/include/asm/numa_64.h5
-rw-r--r--arch/x86/mm/numa_64.c117
4 files changed, 118 insertions, 14 deletions
diff --git a/Documentation/x86/x86_64/boot-options.txt b/Documentation/x86/x86_64/boot-options.txt
index 29a6ff8bc7d3..01150c64aa73 100644
--- a/Documentation/x86/x86_64/boot-options.txt
+++ b/Documentation/x86/x86_64/boot-options.txt
@@ -166,6 +166,10 @@ NUMA
numa=noacpi Don't parse the SRAT table for NUMA setup
+ numa=fake=<size>[MG]
+ If given as a memory unit, fills all system RAM with nodes of
+ size interleaved over physical nodes.
+
numa=fake=CMDLINE
If a number, fakes CMDLINE nodes and ignores NUMA setup of the
actual machine. Otherwise, system memory is configured
diff --git a/arch/x86/include/asm/mmzone_64.h b/arch/x86/include/asm/mmzone_64.h
index a29f48c2a322..288b96f815a6 100644
--- a/arch/x86/include/asm/mmzone_64.h
+++ b/arch/x86/include/asm/mmzone_64.h
@@ -39,11 +39,5 @@ static inline __attribute__((pure)) int phys_to_nid(unsigned long addr)
#define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
#define node_end_pfn(nid) (NODE_DATA(nid)->node_start_pfn + \
NODE_DATA(nid)->node_spanned_pages)
-
-#ifdef CONFIG_NUMA_EMU
-#define FAKE_NODE_MIN_SIZE (64 * 1024 * 1024)
-#define FAKE_NODE_MIN_HASH_MASK (~(FAKE_NODE_MIN_SIZE - 1UL))
-#endif
-
#endif
#endif /* _ASM_X86_MMZONE_64_H */
diff --git a/arch/x86/include/asm/numa_64.h b/arch/x86/include/asm/numa_64.h
index c4ae822e415f..823e070e7c26 100644
--- a/arch/x86/include/asm/numa_64.h
+++ b/arch/x86/include/asm/numa_64.h
@@ -36,6 +36,11 @@ extern void __cpuinit numa_set_node(int cpu, int node);
extern void __cpuinit numa_clear_node(int cpu);
extern void __cpuinit numa_add_cpu(int cpu);
extern void __cpuinit numa_remove_cpu(int cpu);
+
+#ifdef CONFIG_NUMA_EMU
+#define FAKE_NODE_MIN_SIZE ((u64)64 << 20)
+#define FAKE_NODE_MIN_HASH_MASK (~(FAKE_NODE_MIN_SIZE - 1UL))
+#endif /* CONFIG_NUMA_EMU */
#else
static inline void init_cpu_to_node(void) { }
static inline void numa_set_node(int cpu, int node) { }
diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c
index 2ecbe0ca0dfc..c47c78ba3aca 100644
--- a/arch/x86/mm/numa_64.c
+++ b/arch/x86/mm/numa_64.c
@@ -502,6 +502,102 @@ static int __init split_nodes_interleave(u64 addr, u64 max_addr,
}
/*
+ * Returns the end address of a node so that there is at least `size' amount of
+ * non-reserved memory or `max_addr' is reached.
+ */
+static u64 __init find_end_of_node(u64 start, u64 max_addr, u64 size)
+{
+ u64 end = start + size;
+
+ while (end - start - e820_hole_size(start, end) < size) {
+ end += FAKE_NODE_MIN_SIZE;
+ if (end > max_addr) {
+ end = max_addr;
+ break;
+ }
+ }
+ return end;
+}
+
+/*
+ * Sets up fake nodes of `size' interleaved over physical nodes ranging from
+ * `addr' to `max_addr'. The return value is the number of nodes allocated.
+ */
+static int __init split_nodes_size_interleave(u64 addr, u64 max_addr, u64 size)
+{
+ nodemask_t physnode_mask = NODE_MASK_NONE;
+ u64 min_size;
+ int ret = 0;
+ int i;
+
+ if (!size)
+ 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).
+ */
+ min_size = (max_addr - addr - e820_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 (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;
+
+ for (i = 0; i < MAX_NUMNODES; i++)
+ if (physnodes[i].start != physnodes[i].end)
+ node_set(i, physnode_mask);
+ /*
+ * Fill physical nodes with fake nodes of size until there is no memory
+ * left on any of them.
+ */
+ while (nodes_weight(physnode_mask)) {
+ for_each_node_mask(i, physnode_mask) {
+ u64 dma32_end = MAX_DMA32_PFN << PAGE_SHIFT;
+ u64 end;
+
+ end = find_end_of_node(physnodes[i].start,
+ physnodes[i].end, size);
+ /*
+ * If there won't be at least FAKE_NODE_MIN_SIZE of
+ * non-reserved memory in ZONE_DMA32 for the next node,
+ * this one must extend to the boundary.
+ */
+ if (end < dma32_end && dma32_end - end -
+ e820_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
+ end = dma32_end;
+
+ /*
+ * If there won't be enough non-reserved memory for the
+ * next node, this one must extend to the end of the
+ * physical node.
+ */
+ if (physnodes[i].end - end -
+ e820_hole_size(end, physnodes[i].end) < size)
+ end = physnodes[i].end;
+
+ /*
+ * Setup the fake node that will be allocated as bootmem
+ * later. If setup_node_range() returns non-zero, there
+ * is no more memory available on this physical node.
+ */
+ if (setup_node_range(ret++, &physnodes[i].start,
+ end - physnodes[i].start,
+ physnodes[i].end) < 0)
+ node_clear(i, physnode_mask);
+ }
+ }
+ return ret;
+}
+
+/*
* Splits num_nodes nodes up equally starting at node_start. The return value
* is the number of nodes split up and addr is adjusted to be at the end of the
* last node allocated.
@@ -546,14 +642,7 @@ static int __init split_nodes_equally(u64 *addr, u64 max_addr, int node_start,
if (i == num_nodes + node_start - 1)
end = max_addr;
else
- while (end - *addr - e820_hole_size(*addr, end) <
- size) {
- end += FAKE_NODE_MIN_SIZE;
- if (end > max_addr) {
- end = max_addr;
- break;
- }
- }
+ end = find_end_of_node(*addr, max_addr, size);
if (setup_node_range(i, addr, end - *addr, max_addr) < 0)
break;
}
@@ -589,6 +678,18 @@ static int __init numa_emulation(unsigned long start_pfn,
num_phys_nodes = setup_physnodes(addr, max_addr, acpi, k8);
/*
+ * If the numa=fake command-line contains a 'M' or 'G', it represents
+ * the fixed node size.
+ */
+ if (strchr(cmdline, 'M') || strchr(cmdline, 'G')) {
+ size = memparse(cmdline, &cmdline);
+ num_nodes = split_nodes_size_interleave(addr, max_addr, size);
+ if (num_nodes < 0)
+ return num_nodes;
+ goto out;
+ }
+
+ /*
* If the numa=fake command-line is just a single number N, split the
* system RAM into N fake nodes.
*/