[PATCH 6/7] target/i386: Make some PEBS features user-visible

[Zide Chen <zide.chen@intel.com>]

Populate selected PEBS feature names in FEAT_PERF_CAPABILITIES to make
the corresponding bits user-visible CPU feature knobs, allowing them to
be explicitly enabled or disabled via -cpu +/-<feature>.

Once named, these bits become part of the guest CPU configuration
contract.  If a VM is configured with such a feature enabled, migration
to a destination that does not support the feature may fail, as the
destination cannot honor the guest-visible CPU model.

The PEBS_FMT bits are intentionally not exposed. They are not meaningful
as user-visible features, and QEMU registers CPU features as boolean
QOM properties, which makes them unsuitable for representing and
checking numeric capabilities.

Co-developed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Zide Chen <zide.chen@intel.com>
---
 target/i386/cpu.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index f1ac98970d3e..fc6a64287415 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1618,10 +1618,10 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
         .type = MSR_FEATURE_WORD,
         .feat_names = {
             NULL, NULL, NULL, NULL,
+            NULL, NULL, "pebs-trap", "pebs-arch-reg"
             NULL, NULL, NULL, NULL,
-            NULL, NULL, NULL, NULL,
-            NULL, "full-width-write", NULL, NULL,
-            NULL, NULL, NULL, NULL,
+            NULL, "full-width-write", "pebs-baseline", NULL,
+            NULL, "pebs-timing-info", NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
-- 
2.52.0