[libvirt] [PATCH v2 13/30] cpu_x86: Store CPU signature in an array

[Jiri Denemark]

In preparation for storing several CPU signatures in a single CPU model,
we need to turn virCPUx86Model's signature into an array of signatures.

The parser still hardcodes the number of signatures to 1, but the
following patch will drop this limit.

Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
---

Notes:
    Version 2:
    - separated from 11/26 cpu_x86: Allow multiple signatures for a CPU model

 src/cpu/cpu_x86.c | 50 ++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 41 insertions(+), 9 deletions(-)

diff --git a/src/cpu/cpu_x86.c b/src/cpu/cpu_x86.c
index 0be1b12cdb..3577f31aa0 100644
--- a/src/cpu/cpu_x86.c
+++ b/src/cpu/cpu_x86.c
@@ -147,7 +147,8 @@ typedef virCPUx86Model *virCPUx86ModelPtr;
 struct _virCPUx86Model {
     char *name;
     virCPUx86VendorPtr vendor;
-    uint32_t signature;
+    size_t nsignatures;
+    uint32_t *signatures;
     virCPUx86Data data;
 };
 
@@ -974,6 +975,7 @@ x86ModelFree(virCPUx86ModelPtr model)
         return;
 
     VIR_FREE(model->name);
+    VIR_FREE(model->signatures);
     virCPUx86DataClear(&model->data);
     VIR_FREE(model);
 }
@@ -983,7 +985,14 @@ static int
 x86ModelCopySignatures(virCPUx86ModelPtr dst,
                        virCPUx86ModelPtr src)
 {
-    dst->signature = src->signature;
+    size_t i;
+
+    if (VIR_ALLOC_N(dst->signatures, src->nsignatures) < 0)
+        return -1;
+
+    dst->nsignatures = src->nsignatures;
+    for (i = 0; i < src->nsignatures; i++)
+        dst->signatures[i] = src->signatures[i];
 
     return 0;
 }
@@ -1200,12 +1209,18 @@ static int
 x86ModelParseSignature(virCPUx86ModelPtr model,
                        xmlXPathContextPtr ctxt)
 {
+    /* Remove inherited signatures. */
+    VIR_FREE(model->signatures);
 
     if (virXPathBoolean("boolean(./signature)", ctxt)) {
         unsigned int sigFamily = 0;
         unsigned int sigModel = 0;
         int rc;
 
+        model->nsignatures = 1;
+        if (VIR_ALLOC_N(model->signatures, 1) < 0)
+            return -1;
+
         rc = virXPathUInt("string(./signature/@family)", ctxt, &sigFamily);
         if (rc < 0 || sigFamily == 0) {
             virReportError(VIR_ERR_INTERNAL_ERROR,
@@ -1222,7 +1237,7 @@ x86ModelParseSignature(virCPUx86ModelPtr model,
             return -1;
         }
 
-        model->signature = x86MakeSignature(sigFamily, sigModel, 0);
+        model->signatures[0] = x86MakeSignature(sigFamily, sigModel, 0);
     }
 
     return 0;
@@ -1625,7 +1640,8 @@ x86Compute(virCPUDefPtr host,
                                      &host_model->vendor->cpuid) < 0)
             goto error;
 
-        if (x86DataAddSignature(&guest_model->data, host_model->signature) < 0)
+        if (host_model->signatures &&
+            x86DataAddSignature(&guest_model->data, *host_model->signatures) < 0)
             goto error;
 
         if (cpu->type == VIR_CPU_TYPE_GUEST
@@ -1731,6 +1747,21 @@ virCPUx86Compare(virCPUDefPtr host,
 }
 
 
+static bool
+x86ModelHasSignature(virCPUx86ModelPtr model,
+                     uint32_t signature)
+{
+    size_t i;
+
+    for (i = 0; i < model->nsignatures; i++) {
+        if (model->signatures[i] == signature)
+            return true;
+    }
+
+    return false;
+}
+
+
 /*
  * Checks whether a candidate model is a better fit for the CPU data than the
  * current model.
@@ -1772,8 +1803,8 @@ x86DecodeUseCandidate(virCPUx86ModelPtr current,
      * consider candidates with matching family/model.
      */
     if (signature &&
-        current->signature == signature &&
-        candidate->signature != signature) {
+        x86ModelHasSignature(current, signature) &&
+        !x86ModelHasSignature(candidate, signature)) {
         VIR_DEBUG("%s differs in signature from matching %s",
                   cpuCandidate->model, cpuCurrent->model);
         return 0;
@@ -1789,8 +1820,8 @@ x86DecodeUseCandidate(virCPUx86ModelPtr current,
      * result in longer list of features.
      */
     if (signature &&
-        candidate->signature == signature &&
-        current->signature != signature) {
+        x86ModelHasSignature(candidate, signature) &&
+        !x86ModelHasSignature(current, signature)) {
         VIR_DEBUG("%s provides matching signature", cpuCandidate->model);
         return 1;
     }
@@ -2858,7 +2889,8 @@ virCPUx86Translate(virCPUDefPtr cpu,
         virCPUx86DataAddCPUIDInt(&model->data, &model->vendor->cpuid) < 0)
         goto cleanup;
 
-    if (x86DataAddSignature(&model->data, model->signature) < 0)
+    if (model->signatures &&
+        x86DataAddSignature(&model->data, model->signatures[0]) < 0)
         goto cleanup;
 
     if (!(translated = virCPUDefCopyWithoutModel(cpu)))
-- 
2.21.0