Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fixes from Ingo Molnar:
 "Misc kernel fixes: a virtualization environment related fix, an uncore
  PMU driver removal handling fix, a PowerPC fix and new events for
  Knights Landing"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel: Honour the CPUID for number of fixed counters in hypervisors
  perf/powerpc: Don't call perf_event_disable() from atomic context
  perf/core: Protect PMU device removal with a 'pmu_bus_running' check, to fix CONFIG_DEBUG_TEST_DRIVER_REMOVE=y kernel panic
  perf/x86/intel/cstate: Add C-state residency events for Knights Landing

5 files changed, 52 insertions, 14 deletions

diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c
index 9781c69eae57..03d089b3ed72 100644
--- a/arch/powerpc/kernel/hw_breakpoint.c
+++ b/arch/powerpc/kernel/hw_breakpoint.c
@@ -275,7 +275,7 @@ int hw_breakpoint_handler(struct die_args *args)
         if (!stepped) {
                 WARN(1, "Unable to handle hardware breakpoint. Breakpoint at "
                         "0x%lx will be disabled.", info->address);
-                perf_event_disable(bp);
+                perf_event_disable_inatomic(bp);
                 goto out;
         }
         /*
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index eab0915f5995..a74a2dbc0180 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -3607,10 +3607,14 @@ __init int intel_pmu_init(void)
 
         /*
          * Quirk: v2 perfmon does not report fixed-purpose events, so
-         * assume at least 3 events:
+         * assume at least 3 events, when not running in a hypervisor:
          */
-        if (version > 1)
-                x86_pmu.num_counters_fixed = max((int)edx.split.num_counters_fixed, 3);
+        if (version > 1) {
+                int assume = 3 * !boot_cpu_has(X86_FEATURE_HYPERVISOR);
+
+                x86_pmu.num_counters_fixed =
+                        max((int)edx.split.num_counters_fixed, assume);
+        }
 
         if (boot_cpu_has(X86_FEATURE_PDCM)) {
                 u64 capabilities;
diff --git a/arch/x86/events/intel/cstate.c b/arch/x86/events/intel/cstate.c
index 3ca87b5a8677..4f5ac726335f 100644
--- a/arch/x86/events/intel/cstate.c
+++ b/arch/x86/events/intel/cstate.c
@@ -48,7 +48,8 @@
  *                             Scope: Core
  *      MSR_CORE_C6_RESIDENCY: CORE C6 Residency Counter
  *                             perf code: 0x02
- *                             Available model: SLM,AMT,NHM,WSM,SNB,IVB,HSW,BDW,SKL
+ *                             Available model: SLM,AMT,NHM,WSM,SNB,IVB,HSW,BDW
+ *                                              SKL,KNL
  *                             Scope: Core
  *      MSR_CORE_C7_RESIDENCY: CORE C7 Residency Counter
  *                             perf code: 0x03
@@ -56,15 +57,16 @@
  *                             Scope: Core
  *      MSR_PKG_C2_RESIDENCY:  Package C2 Residency Counter.
  *                             perf code: 0x00
- *                             Available model: SNB,IVB,HSW,BDW,SKL
+ *                             Available model: SNB,IVB,HSW,BDW,SKL,KNL
  *                             Scope: Package (physical package)
  *      MSR_PKG_C3_RESIDENCY:  Package C3 Residency Counter.
  *                             perf code: 0x01
- *                             Available model: NHM,WSM,SNB,IVB,HSW,BDW,SKL
+ *                             Available model: NHM,WSM,SNB,IVB,HSW,BDW,SKL,KNL
  *                             Scope: Package (physical package)
  *      MSR_PKG_C6_RESIDENCY:  Package C6 Residency Counter.
  *                             perf code: 0x02
- *                             Available model: SLM,AMT,NHM,WSM,SNB,IVB,HSW,BDW,SKL
+ *                             Available model: SLM,AMT,NHM,WSM,SNB,IVB,HSW,BDW
+ *                                              SKL,KNL
  *                             Scope: Package (physical package)
  *      MSR_PKG_C7_RESIDENCY:  Package C7 Residency Counter.
  *                             perf code: 0x03
@@ -118,6 +120,7 @@ struct cstate_model {
 
 /* Quirk flags */
 #define SLM_PKG_C6_USE_C7_MSR   (1UL << 0)
+#define KNL_CORE_C6_MSR         (1UL << 1)
 
 struct perf_cstate_msr {
         u64     msr;
@@ -488,6 +491,18 @@ static const struct cstate_model slm_cstates __initconst = {
         .quirks                 = SLM_PKG_C6_USE_C7_MSR,
 };
 
+
+static const struct cstate_model knl_cstates __initconst = {
+        .core_events            = BIT(PERF_CSTATE_CORE_C6_RES),
+
+        .pkg_events             = BIT(PERF_CSTATE_PKG_C2_RES) |
+                                  BIT(PERF_CSTATE_PKG_C3_RES) |
+                                  BIT(PERF_CSTATE_PKG_C6_RES),
+        .quirks                 = KNL_CORE_C6_MSR,
+};
+
+
+
 #define X86_CSTATES_MODEL(model, states)                                \
         { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (unsigned long) &(states) }
 
@@ -523,6 +538,8 @@ static const struct x86_cpu_id intel_cstates_match[] __initconst = {
 
         X86_CSTATES_MODEL(INTEL_FAM6_SKYLAKE_MOBILE,  snb_cstates),
         X86_CSTATES_MODEL(INTEL_FAM6_SKYLAKE_DESKTOP, snb_cstates),
+
+        X86_CSTATES_MODEL(INTEL_FAM6_XEON_PHI_KNL, knl_cstates),
         { },
 };
 MODULE_DEVICE_TABLE(x86cpu, intel_cstates_match);
@@ -558,6 +575,11 @@ static int __init cstate_probe(const struct cstate_model *cm)
         if (cm->quirks & SLM_PKG_C6_USE_C7_MSR)
                 pkg_msr[PERF_CSTATE_PKG_C6_RES].msr = MSR_PKG_C7_RESIDENCY;
 
+        /* KNL has different MSR for CORE C6 */
+        if (cm->quirks & KNL_CORE_C6_MSR)
+                pkg_msr[PERF_CSTATE_CORE_C6_RES].msr = MSR_KNL_CORE_C6_RESIDENCY;
+
+
         has_cstate_core = cstate_probe_msr(cm->core_events,
                                            PERF_CSTATE_CORE_EVENT_MAX,
                                            core_msr, core_events_attrs);
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 060d0ede88df..4741ecdb9817 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -1257,6 +1257,7 @@ extern u64 perf_swevent_set_period(struct perf_event *event);
 extern void perf_event_enable(struct perf_event *event);
 extern void perf_event_disable(struct perf_event *event);
 extern void perf_event_disable_local(struct perf_event *event);
+extern void perf_event_disable_inatomic(struct perf_event *event);
 extern void perf_event_task_tick(void);
 #else /* !CONFIG_PERF_EVENTS: */
 static inline void *
diff --git a/kernel/events/core.c b/kernel/events/core.c
index c6e47e97b33f..0e292132efac 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1960,6 +1960,12 @@ void perf_event_disable(struct perf_event *event)
 }
 EXPORT_SYMBOL_GPL(perf_event_disable);
 
+void perf_event_disable_inatomic(struct perf_event *event)
+{
+        event->pending_disable = 1;
+        irq_work_queue(&event->pending);
+}
+
 static void perf_set_shadow_time(struct perf_event *event,
                                  struct perf_event_context *ctx,
                                  u64 tstamp)
@@ -7075,8 +7081,8 @@ static int __perf_event_overflow(struct perf_event *event,
         if (events && atomic_dec_and_test(&event->event_limit)) {
                 ret = 1;
                 event->pending_kill = POLL_HUP;
-                event->pending_disable = 1;
-                irq_work_queue(&event->pending);
+
+                perf_event_disable_inatomic(event);
         }
 
         READ_ONCE(event->overflow_handler)(event, data, regs);
@@ -8855,7 +8861,10 @@ EXPORT_SYMBOL_GPL(perf_pmu_register);
 
 void perf_pmu_unregister(struct pmu *pmu)
 {
+        int remove_device;
+
         mutex_lock(&pmus_lock);
+        remove_device = pmu_bus_running;
         list_del_rcu(&pmu->entry);
         mutex_unlock(&pmus_lock);
 
@@ -8869,10 +8878,12 @@ void perf_pmu_unregister(struct pmu *pmu)
         free_percpu(pmu->pmu_disable_count);
         if (pmu->type >= PERF_TYPE_MAX)
                 idr_remove(&pmu_idr, pmu->type);
-        if (pmu->nr_addr_filters)
-                device_remove_file(pmu->dev, &dev_attr_nr_addr_filters);
-        device_del(pmu->dev);
-        put_device(pmu->dev);
+        if (remove_device) {
+                if (pmu->nr_addr_filters)
+                        device_remove_file(pmu->dev, &dev_attr_nr_addr_filters);
+                device_del(pmu->dev);
+                put_device(pmu->dev);
+        }
         free_pmu_context(pmu);
 }
 EXPORT_SYMBOL_GPL(perf_pmu_unregister);