[PATCH 4/5] cpufreq/amd-cppc: move epp_init into driver data

[Jan Beulich <jbeulich@xxxxxxxx>]

No reason for it to be a separate per-CPU item; it's connected to a
struct cpufreq_policy instance just like other driver data.

This further reduces the concern over amd_cppc_cpufreq_cpu_init() being
called for all CPUs, or a CPU going offline that's recorded in policy->cpu
(which would result in accesses of per-CPU data of offline CPUs).

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/xen/arch/x86/acpi/cpufreq/amd-cppc.c
+++ b/xen/arch/x86/acpi/cpufreq/amd-cppc.c
@@ -35,7 +35,6 @@
  * for freq-to-perf transition
  */
 static DEFINE_PER_CPU_READ_MOSTLY(unsigned int, pxfreq_mhz);
-static DEFINE_PER_CPU_READ_MOSTLY(uint8_t, epp_init);
 #ifndef NDEBUG
 static bool __ro_after_init opt_active_mode;
 #else
@@ -248,7 +247,7 @@ static int cf_check amd_cppc_cpufreq_tar
     amd_cppc_write_request(policy, data->caps.lowest_nonlinear_perf,
                            des_perf, data->caps.highest_perf,
                            /* Pre-defined BIOS value for passive mode */
-                           per_cpu(epp_init, policy->cpu));
+                           data->epp_init);
     return 0;
 }
 
@@ -326,7 +325,7 @@ static void cf_check amd_cppc_init_msrs(
 
     /* Store pre-defined BIOS value for passive mode */
     rdmsrl(MSR_AMD_CPPC_REQ, val);
-    this_cpu(epp_init) = MASK_EXTR(val, AMD_CPPC_EPP_MASK);
+    data->epp_init = MASK_EXTR(val, AMD_CPPC_EPP_MASK);
 
     return;
 
@@ -465,7 +464,7 @@ static void amd_cppc_prepare_policy(stru
         break;
 
     default:
-        *epp = per_cpu(epp_init, policy->cpu);
+        *epp = data->epp_init;
         break;
     }
 }
--- a/xen/include/acpi/cpufreq/cpufreq.h
+++ b/xen/include/acpi/cpufreq/cpufreq.h
@@ -143,6 +143,8 @@ struct amd_cppc_drv_data {
         };
     } req;
 
+    uint8_t epp_init;
+
     int err;
 };