8:44 a.m.
CPU models defined in the cpu_map can use signature/@stepping attribute
to match a limited set of stepping numbers. The value is a bitmap for
bits 0..15 each corresponding to a single stepping value. For example,
stepping='4-6,9' will match 4, 5, 6, and 9. Omitting the attribute is
equivalent to stepping='0-15'.
Signed-off-by: Jiri Denemark <jdenemar(a)redhat.com>
---
src/cpu/cpu_x86.c | 60 +++++++++++++++++++++++++++++++++++++++--------
1 file changed, 50 insertions(+), 10 deletions(-)
diff --git a/src/cpu/cpu_x86.c b/src/cpu/cpu_x86.c
index 51c98efca9..bd224a9d0d 100644
--- a/src/cpu/cpu_x86.c
+++ b/src/cpu/cpu_x86.c
@@ -125,6 +125,7 @@ typedef struct _virCPUx86Signature virCPUx86Signature;
struct _virCPUx86Signature {
unsigned int family;
unsigned int model;
+ virBitmapPtr stepping;
};
typedef struct _virCPUx86Signatures virCPUx86Signatures;
@@ -732,7 +733,17 @@ x86MakeSignature(unsigned int family,
static uint32_t
virCPUx86SignatureToCPUID(virCPUx86Signature *sig)
{
- return x86MakeSignature(sig->family, sig->model, 0);
+ unsigned int stepping = 0;
+
+ if (sig->stepping) {
+ ssize_t fisrtBit;
+
+ fisrtBit = virBitmapNextSetBit(sig->stepping, -1);
+ if (fisrtBit >= 0)
+ stepping = fisrtBit;
+ }
+
+ return x86MakeSignature(sig->family, sig->model, stepping);
}
@@ -767,8 +778,8 @@ x86DataToSignatureFull(const virCPUx86Data *data,
}
-/* Mask out irrelevant bits (R and Step) from processor signature. */
-#define SIGNATURE_MASK 0x0fff3ff0
+/* Mask out reserved bits from processor signature. */
+#define SIGNATURE_MASK 0x0fff3fff
static uint32_t
x86DataToSignature(const virCPUx86Data *data)
@@ -1134,9 +1145,14 @@ virCPUx86SignaturesNew(size_t count)
static void
virCPUx86SignaturesFree(virCPUx86SignaturesPtr sigs)
{
+ size_t i;
+
if (!sigs)
return;
+ for (i = 0; i < sigs->count; i++)
+ virBitmapFree(sigs->items[i].stepping);
+
g_free(sigs->items);
g_free(sigs);
}
@@ -1153,8 +1169,12 @@ virCPUx86SignaturesCopy(virCPUx86SignaturesPtr src)
dst = virCPUx86SignaturesNew(src->count);
- for (i = 0; i < src->count; i++)
- dst->items[i] = src->items[i];
+ for (i = 0; i < src->count; i++) {
+ dst->items[i].family = src->items[i].family;
+ dst->items[i].model = src->items[i].model;
+ if (src->items[i].stepping)
+ dst->items[i].stepping = virBitmapNewCopy(src->items[i].stepping);
+ }
return dst;
}
@@ -1176,7 +1196,9 @@ virCPUx86SignaturesMatch(virCPUx86SignaturesPtr sigs,
for (i = 0; i < sigs->count; i++) {
if (sigs->items[i].family == family &&
- sigs->items[i].model == model)
+ sigs->items[i].model == model &&
+ (!sigs->items[i].stepping ||
+ virBitmapIsBitSet(sigs->items[i].stepping, stepping)))
return true;
}
@@ -1194,9 +1216,15 @@ virCPUx86SignaturesFormat(virCPUx86SignaturesPtr sigs)
return virBufferContentAndReset(&buf);
for (i = 0; i < sigs->count; i++) {
- virBufferAsprintf(&buf, "(%u,%u,0), ",
+ g_autofree char *stepping = NULL;
+
+ if (sigs->items[i].stepping)
+ stepping = virBitmapFormat(sigs->items[i].stepping);
+
+ virBufferAsprintf(&buf, "(%u,%u,%s), ",
sigs->items[i].family,
- sigs->items[i].model);
+ sigs->items[i].model,
+ stepping ? stepping : "0-15");
}
virBufferTrim(&buf, ", ");
@@ -1473,6 +1501,7 @@ x86ModelParseSignatures(virCPUx86ModelPtr model,
for (i = 0; i < n; i++) {
virCPUx86Signature *sig = &model->signatures->items[i];
+ g_autofree char *stepping = NULL;
int rc;
ctxt->node = nodes[i];
@@ -1492,6 +1521,11 @@ x86ModelParseSignatures(virCPUx86ModelPtr model,
model->name);
return -1;
}
+
+ stepping = virXPathString("string(@stepping)", ctxt);
+ /* stepping corresponds to 4 bits in 32b signature, see above */
+ if (stepping && virBitmapParse(stepping, &sig->stepping, 16) <
0)
+ return -1;
}
ctxt->node = root;
@@ -2094,6 +2128,9 @@ x86Decode(virCPUDefPtr cpu,
virDomainCapsCPUModelPtr hvModel = NULL;
g_autofree char *sigs = NULL;
uint32_t signature;
+ unsigned int sigFamily;
+ unsigned int sigModel;
+ unsigned int sigStepping;
ssize_t i;
int rc;
@@ -2107,6 +2144,7 @@ x86Decode(virCPUDefPtr cpu,
vendor = x86DataToVendor(&data, map);
signature = x86DataToSignature(&data);
+ virCPUx86SignatureFromCPUID(signature, &sigFamily, &sigModel,
&sigStepping);
x86DataFilterTSX(&data, vendor, map);
@@ -2188,8 +2226,10 @@ x86Decode(virCPUDefPtr cpu,
sigs = virCPUx86SignaturesFormat(model->signatures);
- VIR_DEBUG("Using CPU model %s (signatures %s) for CPU with signature
%06lx",
- model->name, NULLSTR(sigs), (unsigned long)signature);
+ VIR_DEBUG("Using CPU model %s with signatures [%s] for "
+ "CPU with signature (%u,%u,%u)",
+ model->name, NULLSTR(sigs),
+ sigFamily, sigModel, sigStepping);
cpu->model = g_steal_pointer(&cpuModel->model);
cpu->features = g_steal_pointer(&cpuModel->features);
--
2.26.0