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

Pull SMP hotplug notifier removal from Thomas Gleixner:
 "This is the final cleanup of the hotplug notifier infrastructure. The
  series has been reintgrated in the last two days because there came a
  new driver using the old infrastructure via the SCSI tree.

  Summary:

   - convert the last leftover drivers utilizing notifiers

   - fixup for a completely broken hotplug user

   - prevent setup of already used states

   - removal of the notifiers

   - treewide cleanup of hotplug state names

   - consolidation of state space

  There is a sphinx based documentation pending, but that needs review
  from the documentation folks"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/armada-xp: Consolidate hotplug state space
  irqchip/gic: Consolidate hotplug state space
  coresight/etm3/4x: Consolidate hotplug state space
  cpu/hotplug: Cleanup state names
  cpu/hotplug: Remove obsolete cpu hotplug register/unregister functions
  staging/lustre/libcfs: Convert to hotplug state machine
  scsi/bnx2i: Convert to hotplug state machine
  scsi/bnx2fc: Convert to hotplug state machine
  cpu/hotplug: Prevent overwriting of callbacks
  x86/msr: Remove bogus cleanup from the error path
  bus: arm-ccn: Prevent hotplug callback leak
  perf/x86/intel/cstate: Prevent hotplug callback leak
  ARM/imx/mmcd: Fix broken cpu hotplug handling
  scsi: qedi: Convert to hotplug state machine

1 files changed, 22 insertions, 12 deletions

diff --git a/arch/arm/mach-imx/mmdc.c b/arch/arm/mach-imx/mmdc.c
index ba96bf979625..699157759120 100644
--- a/arch/arm/mach-imx/mmdc.c
+++ b/arch/arm/mach-imx/mmdc.c
@@ -60,6 +60,7 @@
 
 #define to_mmdc_pmu(p) container_of(p, struct mmdc_pmu, pmu)
 
+static enum cpuhp_state cpuhp_mmdc_state;
 static int ddr_type;
 
 struct fsl_mmdc_devtype_data {
@@ -451,8 +452,8 @@ static int imx_mmdc_remove(struct platform_device *pdev)
 {
 	struct mmdc_pmu *pmu_mmdc = platform_get_drvdata(pdev);
 
+	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
 	perf_pmu_unregister(&pmu_mmdc->pmu);
-	cpuhp_remove_state_nocalls(CPUHP_ONLINE);
 	kfree(pmu_mmdc);
 	return 0;
 }
@@ -472,6 +473,18 @@ static int imx_mmdc_perf_init(struct platform_device *pdev, void __iomem *mmdc_b
 		return -ENOMEM;
 	}
 
+	/* The first instance registers the hotplug state */
+	if (!cpuhp_mmdc_state) {
+		ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
+					      "perf/arm/mmdc:online", NULL,
+					      mmdc_pmu_offline_cpu);
+		if (ret < 0) {
+			pr_err("cpuhp_setup_state_multi failed\n");
+			goto pmu_free;
+		}
+		cpuhp_mmdc_state = ret;
+	}
+
 	mmdc_num = mmdc_pmu_init(pmu_mmdc, mmdc_base, &pdev->dev);
 	if (mmdc_num == 0)
 		name = "mmdc";
@@ -485,26 +498,23 @@ static int imx_mmdc_perf_init(struct platform_device *pdev, void __iomem *mmdc_b
 			HRTIMER_MODE_REL);
 	pmu_mmdc->hrtimer.function = mmdc_pmu_timer_handler;
 
-	cpuhp_state_add_instance_nocalls(CPUHP_ONLINE,
-					 &pmu_mmdc->node);
-	cpumask_set_cpu(smp_processor_id(), &pmu_mmdc->cpu);
-	ret = cpuhp_setup_state_multi(CPUHP_AP_NOTIFY_ONLINE,
-				      "MMDC_ONLINE", NULL,
-				      mmdc_pmu_offline_cpu);
-	if (ret) {
-		pr_err("cpuhp_setup_state_multi failure\n");
-		goto pmu_register_err;
-	}
+	cpumask_set_cpu(raw_smp_processor_id(), &pmu_mmdc->cpu);
+
+	/* Register the pmu instance for cpu hotplug */
+	cpuhp_state_add_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
 
 	ret = perf_pmu_register(&(pmu_mmdc->pmu), name, -1);
-	platform_set_drvdata(pdev, pmu_mmdc);
 	if (ret)
 		goto pmu_register_err;
+
+	platform_set_drvdata(pdev, pmu_mmdc);
 	return 0;
 
 pmu_register_err:
 	pr_warn("MMDC Perf PMU failed (%d), disabled\n", ret);
+	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
 	hrtimer_cancel(&pmu_mmdc->hrtimer);
+pmu_free:
 	kfree(pmu_mmdc);
 	return ret;
 }