1 files changed, 13 insertions, 21 deletions

diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c
index df9012bbd211..2d3681bbb522 100644
--- a/arch/x86/kernel/cpu/perf_counter.c
+++ b/arch/x86/kernel/cpu/perf_counter.c
@@ -23,7 +23,6 @@
 #include <asm/stacktrace.h>
 #include <asm/nmi.h>
 
-static bool perf_counters_initialized __read_mostly;
 static u64 perf_counter_mask __read_mostly;
 
 struct cpu_hw_counters {
@@ -227,6 +226,11 @@ static void hw_perf_counter_destroy(struct perf_counter *counter)
         }
 }
 
+static inline int x86_pmu_initialized(void)
+{
+        return x86_pmu.handle_irq != NULL;
+}
+
 /*
  * Setup the hardware configuration for a given hw_event_type
  */
@@ -240,8 +244,8 @@ static int __hw_perf_counter_init(struct perf_counter *counter)
         if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
                 return -ENOSYS;
 
-        if (unlikely(!perf_counters_initialized))
-                return -EINVAL;
+        if (!x86_pmu_initialized())
+                return -ENODEV;
 
         err = 0;
         if (atomic_inc_not_zero(&num_counters)) {
@@ -348,9 +352,8 @@ static u64 amd_pmu_save_disable_all(void)
 
 u64 hw_perf_save_disable(void)
 {
-        if (unlikely(!perf_counters_initialized))
+        if (!x86_pmu_initialized())
                 return 0;
-
         return x86_pmu.save_disable_all();
 }
 /*
@@ -388,9 +391,8 @@ static void amd_pmu_restore_all(u64 ctrl)
 
 void hw_perf_restore(u64 ctrl)
 {
-        if (unlikely(!perf_counters_initialized))
+        if (!x86_pmu_initialized())
                 return;
-
         x86_pmu.restore_all(ctrl);
 }
 /*
@@ -402,8 +404,6 @@ static inline u64 intel_pmu_get_status(u64 mask)
 {
         u64 status;
 
-        if (unlikely(!perf_counters_initialized))
-                return 0;
         rdmsrl(MSR_CORE_PERF_GLOBAL_STATUS, status);
 
         return status;
@@ -417,10 +417,6 @@ static inline void intel_pmu_ack_status(u64 ack)
 static inline void x86_pmu_enable_counter(struct hw_perf_counter *hwc, int idx)
 {
         int err;
-
-        if (unlikely(!perf_counters_initialized))
-                return;
-
         err = checking_wrmsrl(hwc->config_base + idx,
                               hwc->config | ARCH_PERFMON_EVENTSEL0_ENABLE);
 }
@@ -428,10 +424,6 @@ static inline void x86_pmu_enable_counter(struct hw_perf_counter *hwc, int idx)
 static inline void x86_pmu_disable_counter(struct hw_perf_counter *hwc, int idx)
 {
         int err;
-
-        if (unlikely(!perf_counters_initialized))
-                return;
-
         err = checking_wrmsrl(hwc->config_base + idx,
                               hwc->config);
 }
@@ -787,10 +779,10 @@ void perf_counter_unthrottle(void)
 {
         struct cpu_hw_counters *cpuc;
 
-        if (!cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))
+        if (!x86_pmu_initialized())
                 return;
 
-        if (unlikely(!perf_counters_initialized))
+        if (!cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))
                 return;
 
         cpuc = &__get_cpu_var(cpu_hw_counters);
@@ -829,8 +821,9 @@ void perf_counters_lapic_init(int nmi)
 {
         u32 apic_val;
 
-        if (!perf_counters_initialized)
+        if (!x86_pmu_initialized())
                 return;
+
         /*
          * Enable the performance counter vector in the APIC LVT:
          */
@@ -988,7 +981,6 @@ void __init init_hw_perf_counters(void)
                 ((1LL << x86_pmu.num_counters_fixed)-1) << X86_PMC_IDX_FIXED;
 
         pr_info("... counter mask:    %016Lx\n", perf_counter_mask);
-        perf_counters_initialized = true;
 
         perf_counters_lapic_init(0);
         register_die_notifier(&perf_counter_nmi_notifier);