[libvirt] qemu, numa: non-contiguous cpusets
Btw,
while I got your attention, on a not-really related topic: how do we
feel about adding support for specifying a non-contiguous set of cpus
for a numa node in qemu with the -numa option? I.e., like this, for
example:
x86_64-softmmu/qemu-system-x86_64 -smp 8 -numa node,nodeid=0,cpus=0\;2\;4-5 -numa
node,nodeid=1,cpus=1\;3\;6-7
The ';' needs to be escaped from the shell but I'm open for better
suggestions.
Here's a diff:
---
diff --git a/vl.c b/vl.c
index 4e709d5c1c20..82a6c8451fb0 100644
--- a/vl.c
+++ b/vl.c
@@ -1261,9 +1261,27 @@ char *get_boot_devices_list(size_t *size)
return list;
}
+static int __numa_set_cpus(unsigned long *map, int start, int end)
+{
+ if (end >= MAX_CPUMASK_BITS) {
+ end = MAX_CPUMASK_BITS - 1;
+ fprintf(stderr,
+ "qemu: NUMA: A max of %d VCPUs are supported\n",
+ MAX_CPUMASK_BITS);
+ return -EINVAL;
+ }
+
+ if (end < start) {
+ return -EINVAL;
+ }
+
+ bitmap_set(map, start, end-start+1);
+ return 0;
+}
+
static void numa_node_parse_cpus(int nodenr, const char *cpus)
{
- char *endptr;
+ char *endptr, *ptr = (char *)cpus;
unsigned long long value, endvalue;
/* Empty CPU range strings will be considered valid, they will simply
@@ -1273,7 +1291,8 @@ static void numa_node_parse_cpus(int nodenr, const char *cpus)
return;
}
- if (parse_uint(cpus, &value, &endptr, 10) < 0) {
+fromthetop:
+ if (parse_uint(ptr, &value, &endptr, 10) < 0) {
goto error;
}
if (*endptr == '-') {
@@ -1282,22 +1301,22 @@ static void numa_node_parse_cpus(int nodenr, const char *cpus)
}
} else if (*endptr == '\0') {
endvalue = value;
- } else {
- goto error;
- }
+ } else if (*endptr == ';') {
+ if (__numa_set_cpus(node_cpumask[nodenr], value, value) < 0) {
+ goto error;
+ }
+ endptr++;
+ if (*endptr == '\0')
+ return;
- if (endvalue >= MAX_CPUMASK_BITS) {
- endvalue = MAX_CPUMASK_BITS - 1;
- fprintf(stderr,
- "qemu: NUMA: A max of %d VCPUs are supported\n",
- MAX_CPUMASK_BITS);
- }
+ ptr = endptr;
- if (endvalue < value) {
+ goto fromthetop;
+ } else {
goto error;
}
- bitmap_set(node_cpumask[nodenr], value, endvalue-value+1);
+ __numa_set_cpus(node_cpumask[nodenr], value, endvalue);
return;
error:
--
Thanks.
--
Regards/Gruss,
Boris.
Sent from a fat crate under my desk. Formatting is fine.
--