ARM: perf: allocate CPU PMU dynamically at probe time

Supporting multiple, heterogeneous CPU PMUs requires us to allocate the
arm_pmu structures dynamically as the devices are probed.

This patch removes the static structure definitions for each CPU PMU
type and instead passes pointers to the PMU-specific init functions.

Signed-off-by: Sudeep KarkadaNagesha <Sudeep.KarkadaNagesha@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

arch/arm/kernel/perf_event_cpu.c

@@ -23,6 +23,7 @@
 #include <linux/kernel.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/slab.h>
 #include <linux/spinlock.h>
 
 #include <asm/cputype.h>
@@ -195,13 +196,13 @@ static struct platform_device_id __devinitdata cpu_pmu_plat_device_ids[] = {
 /*
  * CPU PMU identification and probing.
  */
-static struct arm_pmu *__devinit probe_current_pmu(void)
+static int __devinit probe_current_pmu(struct arm_pmu *pmu)
 {
-	struct arm_pmu *pmu = NULL;
 	int cpu = get_cpu();
 	unsigned long cpuid = read_cpuid_id();
 	unsigned long implementor = (cpuid & 0xFF000000) >> 24;
 	unsigned long part_number = (cpuid & 0xFFF0);
+	int ret = -ENODEV;
 
 	pr_info("probing PMU on CPU %d\n", cpu);
 
@@ -211,25 +212,25 @@ static struct arm_pmu *__devinit probe_current_pmu(void)
 		case 0xB360:	/* ARM1136 */
 		case 0xB560:	/* ARM1156 */
 		case 0xB760:	/* ARM1176 */
-			pmu = armv6pmu_init();
+			ret = armv6pmu_init(pmu);
 			break;
 		case 0xB020:	/* ARM11mpcore */
-			pmu = armv6mpcore_pmu_init();
+			ret = armv6mpcore_pmu_init(pmu);
 			break;
 		case 0xC080:	/* Cortex-A8 */
-			pmu = armv7_a8_pmu_init();
+			ret = armv7_a8_pmu_init(pmu);
 			break;
 		case 0xC090:	/* Cortex-A9 */
-			pmu = armv7_a9_pmu_init();
+			ret = armv7_a9_pmu_init(pmu);
 			break;
 		case 0xC050:	/* Cortex-A5 */
-			pmu = armv7_a5_pmu_init();
+			ret = armv7_a5_pmu_init(pmu);
 			break;
 		case 0xC0F0:	/* Cortex-A15 */
-			pmu = armv7_a15_pmu_init();
+			ret = armv7_a15_pmu_init(pmu);
 			break;
 		case 0xC070:	/* Cortex-A7 */
-			pmu = armv7_a7_pmu_init();
+			ret = armv7_a7_pmu_init(pmu);
 			break;
 		}
 	/* Intel CPUs [xscale]. */
@@ -237,39 +238,51 @@ static struct arm_pmu *__devinit probe_current_pmu(void)
 		part_number = (cpuid >> 13) & 0x7;
 		switch (part_number) {
 		case 1:
-			pmu = xscale1pmu_init();
+			ret = xscale1pmu_init(pmu);
 			break;
 		case 2:
-			pmu = xscale2pmu_init();
+			ret = xscale2pmu_init(pmu);
 			break;
 		}
 	}
 
 	put_cpu();
-	return pmu;
+	return ret;
 }
 
 static int __devinit cpu_pmu_device_probe(struct platform_device *pdev)
 {
 	const struct of_device_id *of_id;
-	struct arm_pmu *(*init_fn)(void);
+	int (*init_fn)(struct arm_pmu *);
 	struct device_node *node = pdev->dev.of_node;
+	struct arm_pmu *pmu;
+	int ret = -ENODEV;
 
 	if (cpu_pmu) {
 		pr_info("attempt to register multiple PMU devices!");
 		return -ENOSPC;
 	}
 
-	if (node && (of_id = of_match_node(cpu_pmu_of_device_ids, pdev->dev.of_node))) {
-		init_fn = of_id->data;
-		cpu_pmu = init_fn();
-	} else {
-		cpu_pmu = probe_current_pmu();
+	pmu = kzalloc(sizeof(struct arm_pmu), GFP_KERNEL);
+	if (!pmu) {
+		pr_info("failed to allocate PMU device!");
+		return -ENOMEM;
 	}
 
-	if (!cpu_pmu)
-		return -ENODEV;
+	if (node && (of_id = of_match_node(cpu_pmu_of_device_ids, pdev->dev.of_node))) {
+		init_fn = of_id->data;
+		ret = init_fn(pmu);
+	} else {
+		ret = probe_current_pmu(pmu);
+	}
 
+	if (ret) {
+		pr_info("failed to register PMU devices!");
+		kfree(pmu);
+		return ret;
+	}
+
+	cpu_pmu = pmu;
 	cpu_pmu->plat_device = pdev;
 	cpu_pmu_init(cpu_pmu);
 	register_cpu_notifier(&cpu_pmu_hotplug_notifier);

arch/arm/kernel/perf_event_v6.c

@@ -649,24 +649,22 @@ static int armv6_map_event(struct perf_event *event)
 				&armv6_perf_cache_map, 0xFF);
 }
 
-static struct arm_pmu armv6pmu = {
-	.name			= "v6",
-	.handle_irq		= armv6pmu_handle_irq,
-	.enable			= armv6pmu_enable_event,
-	.disable		= armv6pmu_disable_event,
-	.read_counter		= armv6pmu_read_counter,
-	.write_counter		= armv6pmu_write_counter,
-	.get_event_idx		= armv6pmu_get_event_idx,
-	.start			= armv6pmu_start,
-	.stop			= armv6pmu_stop,
-	.map_event		= armv6_map_event,
-	.num_events		= 3,
-	.max_period		= (1LLU << 32) - 1,
-};
-
-static struct arm_pmu *__devinit armv6pmu_init(void)
+static int __devinit armv6pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return &armv6pmu;
+	cpu_pmu->name		= "v6";
+	cpu_pmu->handle_irq	= armv6pmu_handle_irq;
+	cpu_pmu->enable		= armv6pmu_enable_event;
+	cpu_pmu->disable	= armv6pmu_disable_event;
+	cpu_pmu->read_counter	= armv6pmu_read_counter;
+	cpu_pmu->write_counter	= armv6pmu_write_counter;
+	cpu_pmu->get_event_idx	= armv6pmu_get_event_idx;
+	cpu_pmu->start		= armv6pmu_start;
+	cpu_pmu->stop		= armv6pmu_stop;
+	cpu_pmu->map_event	= armv6_map_event;
+	cpu_pmu->num_events	= 3;
+	cpu_pmu->max_period	= (1LLU << 32) - 1;
+
+	return 0;
 }
 
 /*
@@ -683,33 +681,31 @@ static int armv6mpcore_map_event(struct perf_event *event)
 				&armv6mpcore_perf_cache_map, 0xFF);
 }
 
-static struct arm_pmu armv6mpcore_pmu = {
-	.name			= "v6mpcore",
-	.handle_irq		= armv6pmu_handle_irq,
-	.enable			= armv6pmu_enable_event,
-	.disable		= armv6mpcore_pmu_disable_event,
-	.read_counter		= armv6pmu_read_counter,
-	.write_counter		= armv6pmu_write_counter,
-	.get_event_idx		= armv6pmu_get_event_idx,
-	.start			= armv6pmu_start,
-	.stop			= armv6pmu_stop,
-	.map_event		= armv6mpcore_map_event,
-	.num_events		= 3,
-	.max_period		= (1LLU << 32) - 1,
-};
-
-static struct arm_pmu *__devinit armv6mpcore_pmu_init(void)
+static int __devinit armv6mpcore_pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return &armv6mpcore_pmu;
+	cpu_pmu->name		= "v6mpcore";
+	cpu_pmu->handle_irq	= armv6pmu_handle_irq;
+	cpu_pmu->enable		= armv6pmu_enable_event;
+	cpu_pmu->disable	= armv6mpcore_pmu_disable_event;
+	cpu_pmu->read_counter	= armv6pmu_read_counter;
+	cpu_pmu->write_counter	= armv6pmu_write_counter;
+	cpu_pmu->get_event_idx	= armv6pmu_get_event_idx;
+	cpu_pmu->start		= armv6pmu_start;
+	cpu_pmu->stop		= armv6pmu_stop;
+	cpu_pmu->map_event	= armv6mpcore_map_event;
+	cpu_pmu->num_events	= 3;
+	cpu_pmu->max_period	= (1LLU << 32) - 1;
+
+	return 0;
 }
 #else
-static struct arm_pmu *__devinit armv6pmu_init(void)
+static int armv6pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return NULL;
+	return -ENODEV;
 }
 
-static struct arm_pmu *__devinit armv6mpcore_pmu_init(void)
+static int armv6mpcore_pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return NULL;
+	return -ENODEV;
 }
 #endif	/* CONFIG_CPU_V6 || CONFIG_CPU_V6K */

arch/arm/kernel/perf_event_v7.c

@@ -18,8 +18,6 @@
 
 #ifdef CONFIG_CPU_V7
 
-static struct arm_pmu armv7pmu;
-
 /*
  * Common ARMv7 event types
  *
@@ -1014,7 +1012,7 @@ static void armv7pmu_enable_event(struct hw_perf_event *hwc, int idx)
 	 * We only need to set the event for the cycle counter if we
 	 * have the ability to perform event filtering.
 	 */
-	if (armv7pmu.set_event_filter || idx != ARMV7_IDX_CYCLE_COUNTER)
+	if (cpu_pmu->set_event_filter || idx != ARMV7_IDX_CYCLE_COUNTER)
 		armv7_pmnc_write_evtsel(idx, hwc->config_base);
 
 	/*
@@ -1232,17 +1230,18 @@ static int armv7_a7_map_event(struct perf_event *event)
 				&armv7_a7_perf_cache_map, 0xFF);
 }
 
-static struct arm_pmu armv7pmu = {
-	.handle_irq		= armv7pmu_handle_irq,
-	.enable			= armv7pmu_enable_event,
-	.disable		= armv7pmu_disable_event,
-	.read_counter		= armv7pmu_read_counter,
-	.write_counter		= armv7pmu_write_counter,
-	.get_event_idx		= armv7pmu_get_event_idx,
-	.start			= armv7pmu_start,
-	.stop			= armv7pmu_stop,
-	.reset			= armv7pmu_reset,
-	.max_period		= (1LLU << 32) - 1,
+static void armv7pmu_init(struct arm_pmu *cpu_pmu)
+{
+	cpu_pmu->handle_irq	= armv7pmu_handle_irq;
+	cpu_pmu->enable		= armv7pmu_enable_event;
+	cpu_pmu->disable	= armv7pmu_disable_event;
+	cpu_pmu->read_counter	= armv7pmu_read_counter;
+	cpu_pmu->write_counter	= armv7pmu_write_counter;
+	cpu_pmu->get_event_idx	= armv7pmu_get_event_idx;
+	cpu_pmu->start		= armv7pmu_start;
+	cpu_pmu->stop		= armv7pmu_stop;
+	cpu_pmu->reset		= armv7pmu_reset;
+	cpu_pmu->max_period	= (1LLU << 32) - 1;
 };
 
 static u32 __devinit armv7_read_num_pmnc_events(void)
@@ -1256,70 +1255,75 @@ static u32 __devinit armv7_read_num_pmnc_events(void)
 	return nb_cnt + 1;
 }
 
-static struct arm_pmu *__devinit armv7_a8_pmu_init(void)
+static int __devinit armv7_a8_pmu_init(struct arm_pmu *cpu_pmu)
 {
-	armv7pmu.name		= "ARMv7 Cortex-A8";
-	armv7pmu.map_event	= armv7_a8_map_event;
-	armv7pmu.num_events	= armv7_read_num_pmnc_events();
-	return &armv7pmu;
+	armv7pmu_init(cpu_pmu);
+	cpu_pmu->name		= "ARMv7 Cortex-A8";
+	cpu_pmu->map_event	= armv7_a8_map_event;
+	cpu_pmu->num_events	= armv7_read_num_pmnc_events();
+	return 0;
 }
 
-static struct arm_pmu *__devinit armv7_a9_pmu_init(void)
+static int __devinit armv7_a9_pmu_init(struct arm_pmu *cpu_pmu)
 {
-	armv7pmu.name		= "ARMv7 Cortex-A9";
-	armv7pmu.map_event	= armv7_a9_map_event;
-	armv7pmu.num_events	= armv7_read_num_pmnc_events();
-	return &armv7pmu;
+	armv7pmu_init(cpu_pmu);
+	cpu_pmu->name		= "ARMv7 Cortex-A9";
+	cpu_pmu->map_event	= armv7_a9_map_event;
+	cpu_pmu->num_events	= armv7_read_num_pmnc_events();
+	return 0;
 }
 
-static struct arm_pmu *__devinit armv7_a5_pmu_init(void)
+static int __devinit armv7_a5_pmu_init(struct arm_pmu *cpu_pmu)
 {
-	armv7pmu.name		= "ARMv7 Cortex-A5";
-	armv7pmu.map_event	= armv7_a5_map_event;
-	armv7pmu.num_events	= armv7_read_num_pmnc_events();
-	return &armv7pmu;
+	armv7pmu_init(cpu_pmu);
+	cpu_pmu->name		= "ARMv7 Cortex-A5";
+	cpu_pmu->map_event	= armv7_a5_map_event;
+	cpu_pmu->num_events	= armv7_read_num_pmnc_events();
+	return 0;
 }
 
-static struct arm_pmu *__devinit armv7_a15_pmu_init(void)
+static int __devinit armv7_a15_pmu_init(struct arm_pmu *cpu_pmu)
 {
-	armv7pmu.name		= "ARMv7 Cortex-A15";
-	armv7pmu.map_event	= armv7_a15_map_event;
-	armv7pmu.num_events	= armv7_read_num_pmnc_events();
-	armv7pmu.set_event_filter = armv7pmu_set_event_filter;
-	return &armv7pmu;
+	armv7pmu_init(cpu_pmu);
+	cpu_pmu->name		= "ARMv7 Cortex-A15";
+	cpu_pmu->map_event	= armv7_a15_map_event;
+	cpu_pmu->num_events	= armv7_read_num_pmnc_events();
+	cpu_pmu->set_event_filter = armv7pmu_set_event_filter;
+	return 0;
 }
 
-static struct arm_pmu *__devinit armv7_a7_pmu_init(void)
+static int __devinit armv7_a7_pmu_init(struct arm_pmu *cpu_pmu)
 {
-	armv7pmu.name		= "ARMv7 Cortex-A7";
-	armv7pmu.map_event	= armv7_a7_map_event;
-	armv7pmu.num_events	= armv7_read_num_pmnc_events();
-	armv7pmu.set_event_filter = armv7pmu_set_event_filter;
-	return &armv7pmu;
+	armv7pmu_init(cpu_pmu);
+	cpu_pmu->name		= "ARMv7 Cortex-A7";
+	cpu_pmu->map_event	= armv7_a7_map_event;
+	cpu_pmu->num_events	= armv7_read_num_pmnc_events();
+	cpu_pmu->set_event_filter = armv7pmu_set_event_filter;
+	return 0;
 }
 #else
-static struct arm_pmu *__devinit armv7_a8_pmu_init(void)
+static inline int armv7_a8_pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return NULL;
+	return -ENODEV;
 }
 
-static struct arm_pmu *__devinit armv7_a9_pmu_init(void)
+static inline int armv7_a9_pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return NULL;
+	return -ENODEV;
 }
 
-static struct arm_pmu *__devinit armv7_a5_pmu_init(void)
+static inline int armv7_a5_pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return NULL;
+	return -ENODEV;
 }
 
-static struct arm_pmu *__devinit armv7_a15_pmu_init(void)
+static inline int armv7_a15_pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return NULL;
+	return -ENODEV;
 }
 
-static struct arm_pmu *__devinit armv7_a7_pmu_init(void)
+static inline int armv7_a7_pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return NULL;
+	return -ENODEV;
 }
 #endif	/* CONFIG_CPU_V7 */

arch/arm/kernel/perf_event_xscale.c

@@ -434,24 +434,22 @@ static int xscale_map_event(struct perf_event *event)
 				&xscale_perf_cache_map, 0xFF);
 }
 
-static struct arm_pmu xscale1pmu = {
-	.name		= "xscale1",
-	.handle_irq	= xscale1pmu_handle_irq,
-	.enable		= xscale1pmu_enable_event,
-	.disable	= xscale1pmu_disable_event,
-	.read_counter	= xscale1pmu_read_counter,
-	.write_counter	= xscale1pmu_write_counter,
-	.get_event_idx	= xscale1pmu_get_event_idx,
-	.start		= xscale1pmu_start,
-	.stop		= xscale1pmu_stop,
-	.map_event	= xscale_map_event,
-	.num_events	= 3,
-	.max_period	= (1LLU << 32) - 1,
-};
-
-static struct arm_pmu *__devinit xscale1pmu_init(void)
+static int __devinit xscale1pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return &xscale1pmu;
+	cpu_pmu->name		= "xscale1";
+	cpu_pmu->handle_irq	= xscale1pmu_handle_irq;
+	cpu_pmu->enable		= xscale1pmu_enable_event;
+	cpu_pmu->disable	= xscale1pmu_disable_event;
+	cpu_pmu->read_counter	= xscale1pmu_read_counter;
+	cpu_pmu->write_counter	= xscale1pmu_write_counter;
+	cpu_pmu->get_event_idx	= xscale1pmu_get_event_idx;
+	cpu_pmu->start		= xscale1pmu_start;
+	cpu_pmu->stop		= xscale1pmu_stop;
+	cpu_pmu->map_event	= xscale_map_event;
+	cpu_pmu->num_events	= 3;
+	cpu_pmu->max_period	= (1LLU << 32) - 1;
+
+	return 0;
 }
 
 #define XSCALE2_OVERFLOWED_MASK	0x01f
@@ -801,33 +799,31 @@ xscale2pmu_write_counter(int counter, u32 val)
 	}
 }
 
-static struct arm_pmu xscale2pmu = {
-	.name		= "xscale2",
-	.handle_irq	= xscale2pmu_handle_irq,
-	.enable		= xscale2pmu_enable_event,
-	.disable	= xscale2pmu_disable_event,
-	.read_counter	= xscale2pmu_read_counter,
-	.write_counter	= xscale2pmu_write_counter,
-	.get_event_idx	= xscale2pmu_get_event_idx,
-	.start		= xscale2pmu_start,
-	.stop		= xscale2pmu_stop,
-	.map_event	= xscale_map_event,
-	.num_events	= 5,
-	.max_period	= (1LLU << 32) - 1,
-};
-
-static struct arm_pmu *__devinit xscale2pmu_init(void)
+static int __devinit xscale2pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return &xscale2pmu;
+	cpu_pmu->name		= "xscale2";
+	cpu_pmu->handle_irq	= xscale2pmu_handle_irq;
+	cpu_pmu->enable		= xscale2pmu_enable_event;
+	cpu_pmu->disable	= xscale2pmu_disable_event;
+	cpu_pmu->read_counter	= xscale2pmu_read_counter;
+	cpu_pmu->write_counter	= xscale2pmu_write_counter;
+	cpu_pmu->get_event_idx	= xscale2pmu_get_event_idx;
+	cpu_pmu->start		= xscale2pmu_start;
+	cpu_pmu->stop		= xscale2pmu_stop;
+	cpu_pmu->map_event	= xscale_map_event;
+	cpu_pmu->num_events	= 5;
+	cpu_pmu->max_period	= (1LLU << 32) - 1;
+
+	return 0;
 }
 #else
-static struct arm_pmu *__devinit xscale1pmu_init(void)
+static inline int xscale1pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return NULL;
+	return -ENODEV;
 }
 
-static struct arm_pmu *__devinit xscale2pmu_init(void)
+static inline int xscale2pmu_init(struct arm_pmu *cpu_pmu)
 {
-	return NULL;
+	return -ENODEV;
 }
 #endif	/* CONFIG_CPU_XSCALE */