ARM: 7448/1: perf: remove arm_perf_pmu_ids global enumeration

In order to provide PMU name strings compatible with the OProfile
user ABI, an enumeration of all PMUs is currently used by perf to
identify each PMU uniquely. Unfortunately, this does not scale well
in the presence of multiple PMUs and creates a single, global namespace
across all PMUs in the system.

This patch removes the enumeration and instead uses the name string
for the PMU to map onto the OProfile variant. perf_pmu_name is
implemented for CPU PMUs, which is all that OProfile cares about anyway.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/include/asm/perf_event.h b/arch/arm/include/asm/perf_event.h
index 00cbe10a50e3693b32afe48d0d20e3787e9183d0..e074948d81431cec24598e088a696202d52f1615 100644 (file)
--- a/arch/arm/include/asm/perf_event.h
+++ b/arch/arm/include/asm/perf_event.h
@@ -12,21 +12,6 @@
 #ifndef __ARM_PERF_EVENT_H__
 #define __ARM_PERF_EVENT_H__
 
-/* ARM perf PMU IDs for use by internal perf clients. */
-enum arm_perf_pmu_ids {
-       ARM_PERF_PMU_ID_XSCALE1 = 0,
-       ARM_PERF_PMU_ID_XSCALE2,
-       ARM_PERF_PMU_ID_V6,
-       ARM_PERF_PMU_ID_V6MP,
-       ARM_PERF_PMU_ID_CA8,
-       ARM_PERF_PMU_ID_CA9,
-       ARM_PERF_PMU_ID_CA5,
-       ARM_PERF_PMU_ID_CA15,
-       ARM_PERF_PMU_ID_CA7,
-       ARM_NUM_PMU_IDS,
-};
-
-extern enum arm_perf_pmu_ids
-armpmu_get_pmu_id(void);
+/* Nothing to see here... */
 
 #endif /* __ARM_PERF_EVENT_H__ */

diff --git a/arch/arm/include/asm/pmu.h b/arch/arm/include/asm/pmu.h
index 90114faa9f3c7c087f6fce6b871b16ab5e433b44..4432305f4a2aa1b2e89bf69beaf032929816f78d 100644 (file)
--- a/arch/arm/include/asm/pmu.h
+++ b/arch/arm/include/asm/pmu.h
@@ -103,10 +103,9 @@ struct pmu_hw_events {
 
 struct arm_pmu {
        struct pmu      pmu;
-       enum arm_perf_pmu_ids id;
        enum arm_pmu_type type;
        cpumask_t       active_irqs;
-       const char      *name;
+       char            *name;
        irqreturn_t     (*handle_irq)(int irq_num, void *dev);
        void            (*enable)(struct hw_perf_event *evt, int idx);
        void            (*disable)(struct hw_perf_event *evt, int idx);

diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 186c8cb982c543a2cc1631796b34376151b33702..df85eda3add31666dd673d530c6837dc4662195a 100644 (file)
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -47,17 +47,14 @@ static DEFINE_PER_CPU(struct pmu_hw_events, cpu_hw_events);
 /* Set at runtime when we know what CPU type we are. */
 static struct arm_pmu *cpu_pmu;
 
-enum arm_perf_pmu_ids
-armpmu_get_pmu_id(void)
+const char *perf_pmu_name(void)
 {
-       int id = -ENODEV;
-
-       if (cpu_pmu != NULL)
-               id = cpu_pmu->id;
+       if (!cpu_pmu)
+               return NULL;
 
-       return id;
+       return cpu_pmu->pmu.name;
 }
-EXPORT_SYMBOL_GPL(armpmu_get_pmu_id);
+EXPORT_SYMBOL_GPL(perf_pmu_name);
 
 int perf_num_counters(void)
 {
@@ -760,7 +757,7 @@ init_hw_perf_events(void)
                        cpu_pmu->name, cpu_pmu->num_events);
                cpu_pmu_init(cpu_pmu);
                register_cpu_notifier(&pmu_cpu_notifier);
-               armpmu_register(cpu_pmu, "cpu", PERF_TYPE_RAW);
+               armpmu_register(cpu_pmu, cpu_pmu->name, PERF_TYPE_RAW);
        } else {
                pr_info("no hardware support available\n");
        }

diff --git a/arch/arm/kernel/perf_event_v6.c b/arch/arm/kernel/perf_event_v6.c
index ab627a740fa37409258b24441ae7c0b5aec7e7f6..c90fcb2b69676b1f462c5be0160de35d9b2f1b26 100644 (file)
--- a/arch/arm/kernel/perf_event_v6.c
+++ b/arch/arm/kernel/perf_event_v6.c
@@ -650,7 +650,6 @@ static int armv6_map_event(struct perf_event *event)
 }
 
 static struct arm_pmu armv6pmu = {
-       .id                     = ARM_PERF_PMU_ID_V6,
        .name                   = "v6",
        .handle_irq             = armv6pmu_handle_irq,
        .enable                 = armv6pmu_enable_event,
@@ -685,7 +684,6 @@ static int armv6mpcore_map_event(struct perf_event *event)
 }
 
 static struct arm_pmu armv6mpcore_pmu = {
-       .id                     = ARM_PERF_PMU_ID_V6MP,
        .name                   = "v6mpcore",
        .handle_irq             = armv6pmu_handle_irq,
        .enable                 = armv6pmu_enable_event,

diff --git a/arch/arm/kernel/perf_event_v7.c b/arch/arm/kernel/perf_event_v7.c
index d3c536068162d30ec782c60eb780e6514e4784b5..f04070bd21838dd9146d694066d756d2bb1e753a 100644 (file)
--- a/arch/arm/kernel/perf_event_v7.c
+++ b/arch/arm/kernel/perf_event_v7.c
@@ -1258,7 +1258,6 @@ static u32 __init armv7_read_num_pmnc_events(void)
 
 static struct arm_pmu *__init armv7_a8_pmu_init(void)
 {
-       armv7pmu.id             = ARM_PERF_PMU_ID_CA8;
        armv7pmu.name           = "ARMv7 Cortex-A8";
        armv7pmu.map_event      = armv7_a8_map_event;
        armv7pmu.num_events     = armv7_read_num_pmnc_events();
@@ -1267,7 +1266,6 @@ static struct arm_pmu *__init armv7_a8_pmu_init(void)
 
 static struct arm_pmu *__init armv7_a9_pmu_init(void)
 {
-       armv7pmu.id             = ARM_PERF_PMU_ID_CA9;
        armv7pmu.name           = "ARMv7 Cortex-A9";
        armv7pmu.map_event      = armv7_a9_map_event;
        armv7pmu.num_events     = armv7_read_num_pmnc_events();
@@ -1276,7 +1274,6 @@ static struct arm_pmu *__init armv7_a9_pmu_init(void)
 
 static struct arm_pmu *__init armv7_a5_pmu_init(void)
 {
-       armv7pmu.id             = ARM_PERF_PMU_ID_CA5;
        armv7pmu.name           = "ARMv7 Cortex-A5";
        armv7pmu.map_event      = armv7_a5_map_event;
        armv7pmu.num_events     = armv7_read_num_pmnc_events();
@@ -1285,7 +1282,6 @@ static struct arm_pmu *__init armv7_a5_pmu_init(void)
 
 static struct arm_pmu *__init armv7_a15_pmu_init(void)
 {
-       armv7pmu.id             = ARM_PERF_PMU_ID_CA15;
        armv7pmu.name           = "ARMv7 Cortex-A15";
        armv7pmu.map_event      = armv7_a15_map_event;
        armv7pmu.num_events     = armv7_read_num_pmnc_events();
@@ -1295,7 +1291,6 @@ static struct arm_pmu *__init armv7_a15_pmu_init(void)
 
 static struct arm_pmu *__init armv7_a7_pmu_init(void)
 {
-       armv7pmu.id             = ARM_PERF_PMU_ID_CA7;
        armv7pmu.name           = "ARMv7 Cortex-A7";
        armv7pmu.map_event      = armv7_a7_map_event;
        armv7pmu.num_events     = armv7_read_num_pmnc_events();

diff --git a/arch/arm/kernel/perf_event_xscale.c b/arch/arm/kernel/perf_event_xscale.c
index e34e7254e65263ee66cfc7d2d5397980aaf6b399..f759fe0bab632303b34484001ca2b6a9e91452f1 100644 (file)
--- a/arch/arm/kernel/perf_event_xscale.c
+++ b/arch/arm/kernel/perf_event_xscale.c
@@ -435,7 +435,6 @@ static int xscale_map_event(struct perf_event *event)
 }
 
 static struct arm_pmu xscale1pmu = {
-       .id             = ARM_PERF_PMU_ID_XSCALE1,
        .name           = "xscale1",
        .handle_irq     = xscale1pmu_handle_irq,
        .enable         = xscale1pmu_enable_event,
@@ -803,7 +802,6 @@ xscale2pmu_write_counter(int counter, u32 val)
 }
 
 static struct arm_pmu xscale2pmu = {
-       .id             = ARM_PERF_PMU_ID_XSCALE2,
        .name           = "xscale2",
        .handle_irq     = xscale2pmu_handle_irq,
        .enable         = xscale2pmu_enable_event,

diff --git a/arch/arm/oprofile/common.c b/arch/arm/oprofile/common.c
index 4e0a371630b38fb3a950b9063f30a53d3ed0b5a7..99c63d4b6af8ad2060ca6f7ed6b7972b9387ac30 100644 (file)
--- a/arch/arm/oprofile/common.c
+++ b/arch/arm/oprofile/common.c
@@ -23,26 +23,37 @@
 #include <asm/ptrace.h>
 
 #ifdef CONFIG_HW_PERF_EVENTS
+
+/*
+ * OProfile has a curious naming scheme for the ARM PMUs, but they are
+ * part of the user ABI so we need to map from the perf PMU name for
+ * supported PMUs.
+ */
+static struct op_perf_name {
+       char *perf_name;
+       char *op_name;
+} op_perf_name_map[] = {
+       { "xscale1",            "arm/xscale1"   },
+       { "xscale1",            "arm/xscale2"   },
+       { "v6",                 "arm/armv6"     },
+       { "v6mpcore",           "arm/mpcore"    },
+       { "ARMv7 Cortex-A8",    "arm/armv7"     },
+       { "ARMv7 Cortex-A9",    "arm/armv7-ca9" },
+};
+
 char *op_name_from_perf_id(void)
 {
-       enum arm_perf_pmu_ids id = armpmu_get_pmu_id();
-
-       switch (id) {
-       case ARM_PERF_PMU_ID_XSCALE1:
-               return "arm/xscale1";
-       case ARM_PERF_PMU_ID_XSCALE2:
-               return "arm/xscale2";
-       case ARM_PERF_PMU_ID_V6:
-               return "arm/armv6";
-       case ARM_PERF_PMU_ID_V6MP:
-               return "arm/mpcore";
-       case ARM_PERF_PMU_ID_CA8:
-               return "arm/armv7";
-       case ARM_PERF_PMU_ID_CA9:
-               return "arm/armv7-ca9";
-       default:
-               return NULL;
+       int i;
+       struct op_perf_name names;
+       const char *perf_name = perf_pmu_name();
+
+       for (i = 0; i < ARRAY_SIZE(op_perf_name_map); ++i) {
+               names = op_perf_name_map[i];
+               if (!strcmp(names.perf_name, perf_name))
+                       return names.op_name;
        }
+
+       return NULL;
 }
 #endif