Extends the numa=fake x86_64 command-line option to split the remaining
system memory into equal-sized nodes.
For example:
numa=fake=2*512,4* gives two 512M nodes and the remaining system
memory is split into four approximately equal
chunks.
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: David Rientjes <rientjes@cs.washington.edu>
---
Documentation/x86_64/boot-options.txt | 4 +++-
arch/x86_64/mm/numa.c | 24 +++++++++++++++++++-----
2 files changed, 22 insertions(+), 6 deletions(-)
diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt
index 6ccdb5e..0721416 100644
--- a/Documentation/x86_64/boot-options.txt
+++ b/Documentation/x86_64/boot-options.txt
@@ -155,7 +155,9 @@ NUMA
depending on the sizes and coefficients listed. For example:
numa=fake=2*512,1024,4*256
gives two 512M nodes, a 1024M node, and four 256M nodes. If
- the last character of CMDLINE is a comma, the remaining system
+ the last character of CMDLINE is a *, the remaining system
+ memory is divided up equally among its previous coefficient.
+ If the last character is a comma, the remaining system
memory is not allocated to an additional node.
numa=hotadd=percent
diff --git a/arch/x86_64/mm/numa.c b/arch/x86_64/mm/numa.c
index 0417921..3344d60 100644
--- a/arch/x86_64/mm/numa.c
+++ b/arch/x86_64/mm/numa.c
@@ -415,11 +415,25 @@ static int __init numa_emulation(unsigned long start_pfn, unsigned long end_pfn)
done:
if (!num_nodes)
return -1;
- /* Fill remainder of system RAM with a final node, if appropriate. */
- if (addr < max_addr && *(cmdline - 1) != ',') {
- setup_node_range(num_nodes, nodes, &addr, max_addr - addr,
- max_addr);
- num_nodes++;
+ /* Fill remainder of system RAM, if appropriate. */
+ if (addr < max_addr) {
+ switch (*(cmdline - 1)) {
+ case '*':
+ /* Split remaining nodes into coeff chunks */
+ if (coeff <= 0)
+ break;
+ num_nodes += split_nodes_equally(nodes, &addr, max_addr,
+ num_nodes, coeff);
+ break;
+ case ',':
+ /* Do not allocate remaining system RAM */
+ break;
+ default:
+ /* Give one final node */
+ setup_node_range(num_nodes, nodes, &addr,
+ max_addr - addr, max_addr);
+ num_nodes++;
+ }
}
out:
memnode_shift = compute_hash_shift(nodes, num_nodes);
-
