intel/VPMU: MSR_CORE_PERF_GLOBAL_CTRL should be initialized to zero

MSR_CORE_PERF_GLOBAL_CTRL register should be set zero initially. It is up to
the guest to set it so that counters are enabled.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Dietmar Hahn <dietmar.hahn@ts.fujitsu.com>
Tested-by: Dietmar Hahn <dietmar.hahn@ts.fujitsu.com>

diff --git a/xen/arch/x86/hvm/vmx/vpmu_core2.c b/xen/arch/x86/hvm/vmx/vpmu_core2.c
index 8b84079a7bb9f2a2b20ae6cf9eac3abc4481e9ee..77931452e60f757c817f2e27876d24393b884cf1 100644 (file)
--- a/xen/arch/x86/hvm/vmx/vpmu_core2.c
+++ b/xen/arch/x86/hvm/vmx/vpmu_core2.c
@@ -165,14 +165,6 @@ static int core2_get_fixed_pmc_count(void)
     return MASK_EXTR(eax, PMU_FIXED_NR_MASK);
 }
 
-static u64 core2_calc_intial_glb_ctrl_msr(void)
-{
-    int arch_pmc_bits = (1 << arch_pmc_cnt) - 1;
-    u64 fix_pmc_bits  = (1 << fixed_pmc_cnt) - 1;
-
-    return (fix_pmc_bits << 32) | arch_pmc_bits;
-}
-
 /* edx bits 5-12: Bit width of fixed-function performance counters  */
 static int core2_get_bitwidth_fix_count(void)
 {
@@ -373,8 +365,7 @@ static int core2_vpmu_alloc_resource(struct vcpu *v)
 
     if ( vmx_add_guest_msr(MSR_CORE_PERF_GLOBAL_CTRL) )
         goto out_err;
-    vmx_write_guest_msr(MSR_CORE_PERF_GLOBAL_CTRL,
-                 core2_calc_intial_glb_ctrl_msr());
+    vmx_write_guest_msr(MSR_CORE_PERF_GLOBAL_CTRL, 0);
 
     core2_vpmu_cxt = xzalloc_bytes(sizeof(struct core2_vpmu_context) +
                     (arch_pmc_cnt-1)*sizeof(struct arch_msr_pair));