Extends the numa=fake x86_64 command-line option to split the remaining
system memory into nodes of fixed size. Any leftover memory is allocated
to a final node unless the command-line ends with a comma.
For example:
numa=fake=2*512,*128 gives two 512M nodes and the remaining system
memory is split into nodes of 128M each.
Cc: Andi Kleen <[email protected]>
Signed-off-by: David Rientjes <[email protected]>
---
Documentation/x86_64/boot-options.txt | 15 ++++++----
arch/x86_64/mm/numa.c | 47 ++++++++++++++++++++++++++-------
2 files changed, 46 insertions(+), 16 deletions(-)
diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt
index 0721416..9917b9f 100644
--- a/Documentation/x86_64/boot-options.txt
+++ b/Documentation/x86_64/boot-options.txt
@@ -153,12 +153,15 @@ NUMA
If a number, fakes CMDLINE nodes and ignores NUMA setup of the
actual machine. Otherwise, system memory is configured
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 *, 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=fake=2*512,1024,4*256,*128
+ gives two 512M nodes, a 1024M node, four 256M nodes, and the
+ rest split into 128M chunks. If the last character of CMDLINE
+ is a *, the remaining memory is divided up equally among its
+ coefficient:
+ numa=fake=2*512,2*
+ gives two 512M nodes and the rest split into two nodes. If
+ the last character is a comma, the remaining system memory is
+ not allocated to an additional node.
numa=hotadd=percent
Only allow hotadd memory to preallocate page structures upto
diff --git a/arch/x86_64/mm/numa.c b/arch/x86_64/mm/numa.c
index 3344d60..2ee228b 100644
--- a/arch/x86_64/mm/numa.c
+++ b/arch/x86_64/mm/numa.c
@@ -359,6 +359,21 @@ static int split_nodes_equally(struct bootnode *nodes, u64 *addr, u64 max_addr,
}
/*
+ * Splits the remaining system RAM into chunks of size. The remaining memory is
+ * always assigned to a final node and can be asymmetric. Returns the number of
+ * nodes split.
+ */
+static int split_nodes_by_size(struct bootnode *nodes, u64 *addr, u64 max_addr,
+ int node_start, u64 size)
+{
+ int i = node_start;
+ size = (size << 20) & FAKE_NODE_MIN_HASH_MASK;
+ while (!setup_node_range(i++, nodes, addr, size, max_addr))
+ ;
+ return i - node_start;
+}
+
+/*
* Sets up the system RAM area from start_pfn to end_pfn according to the
* numa=fake command-line option.
*/
@@ -367,9 +382,10 @@ static int __init numa_emulation(unsigned long start_pfn, unsigned long end_pfn)
struct bootnode nodes[MAX_NUMNODES];
u64 addr = start_pfn << PAGE_SHIFT;
u64 max_addr = end_pfn << PAGE_SHIFT;
- unsigned int coeff;
- unsigned int num = 0;
int num_nodes = 0;
+ int coeff_flag;
+ int coeff = -1;
+ int num = 0;
u64 size;
int i;
@@ -387,29 +403,34 @@ static int __init numa_emulation(unsigned long start_pfn, unsigned long end_pfn)
}
/* Parse the command line. */
- for (coeff = 1; ; cmdline++) {
+ for (coeff_flag = 0; ; cmdline++) {
if (*cmdline && isdigit(*cmdline)) {
num = num * 10 + *cmdline - '0';
continue;
}
- if (*cmdline == '*')
- coeff = num;
+ if (*cmdline == '*') {
+ if (num > 0)
+ coeff = num;
+ coeff_flag = 1;
+ }
if (!*cmdline || *cmdline == ',') {
+ if (!coeff_flag)
+ coeff = 1;
/*
* Round down to the nearest FAKE_NODE_MIN_SIZE.
* Command-line coefficients are in megabytes.
*/
size = (num << 20) & FAKE_NODE_MIN_HASH_MASK;
- if (size) {
+ if (size)
for (i = 0; i < coeff; i++, num_nodes++)
if (setup_node_range(num_nodes, nodes,
&addr, size, max_addr) < 0)
goto done;
- coeff = 1;
- }
+ if (!*cmdline)
+ break;
+ coeff_flag = 0;
+ coeff = -1;
}
- if (!*cmdline)
- break;
num = 0;
}
done:
@@ -417,6 +438,12 @@ done:
return -1;
/* Fill remainder of system RAM, if appropriate. */
if (addr < max_addr) {
+ if (coeff_flag && coeff < 0) {
+ /* Split remaining nodes into num-sized chunks */
+ num_nodes += split_nodes_by_size(nodes, &addr, max_addr,
+ num_nodes, num);
+ goto out;
+ }
switch (*(cmdline - 1)) {
case '*':
/* Split remaining nodes into coeff chunks */
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
