diff options
| -rw-r--r-- | arch/arm/oprofile/common.c | 333 |
1 files changed, 281 insertions, 52 deletions
diff --git a/arch/arm/oprofile/common.c b/arch/arm/oprofile/common.c index 3fcd752d6146..aad83df89bac 100644 --- a/arch/arm/oprofile/common.c +++ b/arch/arm/oprofile/common.c @@ -2,32 +2,183 @@ * @file common.c * * @remark Copyright 2004 Oprofile Authors + * @remark Copyright 2010 ARM Ltd. * @remark Read the file COPYING * * @author Zwane Mwaikambo + * @author Will Deacon [move to perf] */ +#include <linux/cpumask.h> +#include <linux/errno.h> #include <linux/init.h> +#include <linux/mutex.h> #include <linux/oprofile.h> -#include <linux/errno.h> +#include <linux/perf_event.h> #include <linux/slab.h> #include <linux/sysdev.h> -#include <linux/mutex.h> +#include <asm/stacktrace.h> +#include <linux/uaccess.h> + +#include <asm/perf_event.h> +#include <asm/ptrace.h> -#include "op_counter.h" -#include "op_arm_model.h" +#ifdef CONFIG_HW_PERF_EVENTS +/* + * Per performance monitor configuration as set via oprofilefs. + */ +struct op_counter_config { + unsigned long count; + unsigned long enabled; + unsigned long event; + unsigned long unit_mask; + unsigned long kernel; + unsigned long user; + struct perf_event_attr attr; +}; -static struct op_arm_model_spec *op_arm_model; static int op_arm_enabled; static DEFINE_MUTEX(op_arm_mutex); -struct op_counter_config *counter_config; +static struct op_counter_config *counter_config; +static struct perf_event **perf_events[nr_cpumask_bits]; +static int perf_num_counters; + +/* + * Overflow callback for oprofile. + */ +static void op_overflow_handler(struct perf_event *event, int unused, + struct perf_sample_data *data, struct pt_regs *regs) +{ + int id; + u32 cpu = smp_processor_id(); + + for (id = 0; id < perf_num_counters; ++id) + if (perf_events[cpu][id] == event) + break; + + if (id != perf_num_counters) + oprofile_add_sample(regs, id); + else + pr_warning("oprofile: ignoring spurious overflow " + "on cpu %u\n", cpu); +} + +/* + * Called by op_arm_setup to create perf attributes to mirror the oprofile + * settings in counter_config. Attributes are created as `pinned' events and + * so are permanently scheduled on the PMU. + */ +static void op_perf_setup(void) +{ + int i; + u32 size = sizeof(struct perf_event_attr); + struct perf_event_attr *attr; + + for (i = 0; i < perf_num_counters; ++i) { + attr = &counter_config[i].attr; + memset(attr, 0, size); + attr->type = PERF_TYPE_RAW; + attr->size = size; + attr->config = counter_config[i].event; + attr->sample_period = counter_config[i].count; + attr->pinned = 1; + } +} + +static int op_create_counter(int cpu, int event) +{ + int ret = 0; + struct perf_event *pevent; + + if (!counter_config[event].enabled || (perf_events[cpu][event] != NULL)) + return ret; + + pevent = perf_event_create_kernel_counter(&counter_config[event].attr, + cpu, -1, + op_overflow_handler); + + if (IS_ERR(pevent)) { + ret = PTR_ERR(pevent); + } else if (pevent->state != PERF_EVENT_STATE_ACTIVE) { + pr_warning("oprofile: failed to enable event %d " + "on CPU %d\n", event, cpu); + ret = -EBUSY; + } else { + perf_events[cpu][event] = pevent; + } + + return ret; +} + +static void op_destroy_counter(int cpu, int event) +{ + struct perf_event *pevent = perf_events[cpu][event]; + + if (pevent) { + perf_event_release_kernel(pevent); + perf_events[cpu][event] = NULL; + } +} + +/* + * Called by op_arm_start to create active perf events based on the + * perviously configured attributes. + */ +static int op_perf_start(void) +{ + int cpu, event, ret = 0; + + for_each_online_cpu(cpu) { + for (event = 0; event < perf_num_counters; ++event) { + ret = op_create_counter(cpu, event); + if (ret) + goto out; + } + } + +out: + return ret; +} + +/* + * Called by op_arm_stop at the end of a profiling run. + */ +static void op_perf_stop(void) +{ + int cpu, event; + + for_each_online_cpu(cpu) + for (event = 0; event < perf_num_counters; ++event) + op_destroy_counter(cpu, event); +} + + +static char *op_name_from_perf_id(enum arm_perf_pmu_ids 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; + } +} static int op_arm_create_files(struct super_block *sb, struct dentry *root) { unsigned int i; - for (i = 0; i < op_arm_model->num_counters; i++) { + for (i = 0; i < perf_num_counters; i++) { struct dentry *dir; char buf[4]; @@ -46,12 +197,10 @@ static int op_arm_create_files(struct super_block *sb, struct dentry *root) static int op_arm_setup(void) { - int ret; - spin_lock(&oprofilefs_lock); - ret = op_arm_model->setup_ctrs(); + op_perf_setup(); spin_unlock(&oprofilefs_lock); - return ret; + return 0; } static int op_arm_start(void) @@ -60,8 +209,9 @@ static int op_arm_start(void) mutex_lock(&op_arm_mutex); if (!op_arm_enabled) { - ret = op_arm_model->start(); - op_arm_enabled = !ret; + ret = 0; + op_perf_start(); + op_arm_enabled = 1; } mutex_unlock(&op_arm_mutex); return ret; @@ -71,7 +221,7 @@ static void op_arm_stop(void) { mutex_lock(&op_arm_mutex); if (op_arm_enabled) - op_arm_model->stop(); + op_perf_stop(); op_arm_enabled = 0; mutex_unlock(&op_arm_mutex); } @@ -81,7 +231,7 @@ static int op_arm_suspend(struct sys_device *dev, pm_message_t state) { mutex_lock(&op_arm_mutex); if (op_arm_enabled) - op_arm_model->stop(); + op_perf_stop(); mutex_unlock(&op_arm_mutex); return 0; } @@ -89,7 +239,7 @@ static int op_arm_suspend(struct sys_device *dev, pm_message_t state) static int op_arm_resume(struct sys_device *dev) { mutex_lock(&op_arm_mutex); - if (op_arm_enabled && op_arm_model->start()) + if (op_arm_enabled && op_perf_start()) op_arm_enabled = 0; mutex_unlock(&op_arm_mutex); return 0; @@ -126,58 +276,137 @@ static void exit_driverfs(void) #define exit_driverfs() do { } while (0) #endif /* CONFIG_PM */ -int __init oprofile_arch_init(struct oprofile_operations *ops) +static int report_trace(struct stackframe *frame, void *d) { - struct op_arm_model_spec *spec = NULL; - int ret = -ENODEV; + unsigned int *depth = d; - ops->backtrace = arm_backtrace; + if (*depth) { + oprofile_add_trace(frame->pc); + (*depth)--; + } -#ifdef CONFIG_CPU_XSCALE - spec = &op_xscale_spec; -#endif + return *depth == 0; +} -#ifdef CONFIG_OPROFILE_ARMV6 - spec = &op_armv6_spec; -#endif +/* + * The registers we're interested in are at the end of the variable + * length saved register structure. The fp points at the end of this + * structure so the address of this struct is: + * (struct frame_tail *)(xxx->fp)-1 + */ +struct frame_tail { + struct frame_tail *fp; + unsigned long sp; + unsigned long lr; +} __attribute__((packed)); -#ifdef CONFIG_OPROFILE_MPCORE - spec = &op_mpcore_spec; -#endif +static struct frame_tail* user_backtrace(struct frame_tail *tail) +{ + struct frame_tail buftail[2]; -#ifdef CONFIG_OPROFILE_ARMV7 - spec = &op_armv7_spec; -#endif + /* Also check accessibility of one struct frame_tail beyond */ + if (!access_ok(VERIFY_READ, tail, sizeof(buftail))) + return NULL; + if (__copy_from_user_inatomic(buftail, tail, sizeof(buftail))) + return NULL; - if (spec) { - ret = spec->init(); - if (ret < 0) - return ret; + oprofile_add_trace(buftail[0].lr); - counter_config = kcalloc(spec->num_counters, sizeof(struct op_counter_config), - GFP_KERNEL); - if (!counter_config) - return -ENOMEM; + /* frame pointers should strictly progress back up the stack + * (towards higher addresses) */ + if (tail >= buftail[0].fp) + return NULL; + + return buftail[0].fp-1; +} + +static void arm_backtrace(struct pt_regs * const regs, unsigned int depth) +{ + struct frame_tail *tail = ((struct frame_tail *) regs->ARM_fp) - 1; + + if (!user_mode(regs)) { + struct stackframe frame; + frame.fp = regs->ARM_fp; + frame.sp = regs->ARM_sp; + frame.lr = regs->ARM_lr; + frame.pc = regs->ARM_pc; + walk_stackframe(&frame, report_trace, &depth); + return; + } + + while (depth-- && tail && !((unsigned long) tail & 3)) + tail = user_backtrace(tail); +} + +int __init oprofile_arch_init(struct oprofile_operations *ops) +{ + int cpu, ret = 0; + + perf_num_counters = armpmu_get_max_events(); + + counter_config = kcalloc(perf_num_counters, + sizeof(struct op_counter_config), GFP_KERNEL); - op_arm_model = spec; - init_driverfs(); - ops->create_files = op_arm_create_files; - ops->setup = op_arm_setup; - ops->shutdown = op_arm_stop; - ops->start = op_arm_start; - ops->stop = op_arm_stop; - ops->cpu_type = op_arm_model->name; - printk(KERN_INFO "oprofile: using %s\n", spec->name); + if (!counter_config) { + pr_info("oprofile: failed to allocate %d " + "counters\n", perf_num_counters); + return -ENOMEM; } + for_each_possible_cpu(cpu) { + perf_events[cpu] = kcalloc(perf_num_counters, + sizeof(struct perf_event *), GFP_KERNEL); + if (!perf_events[cpu]) { + pr_info("oprofile: failed to allocate %d perf events " + "for cpu %d\n", perf_num_counters, cpu); + while (--cpu >= 0) + kfree(perf_events[cpu]); + return -ENOMEM; + } + } + + init_driverfs(); + ops->backtrace = arm_backtrace; + ops->create_files = op_arm_create_files; + ops->setup = op_arm_setup; + ops->start = op_arm_start; + ops->stop = op_arm_stop; + ops->shutdown = op_arm_stop; + ops->cpu_type = op_name_from_perf_id(armpmu_get_pmu_id()); + + if (!ops->cpu_type) + ret = -ENODEV; + else + pr_info("oprofile: using %s\n", ops->cpu_type); + return ret; } void oprofile_arch_exit(void) { - if (op_arm_model) { + int cpu, id; + struct perf_event *event; + + if (*perf_events) { exit_driverfs(); - op_arm_model = NULL; + for_each_possible_cpu(cpu) { + for (id = 0; id < perf_num_counters; ++id) { + event = perf_events[cpu][id]; + if (event != NULL) + perf_event_release_kernel(event); + } + kfree(perf_events[cpu]); + } } - kfree(counter_config); + + if (counter_config) + kfree(counter_config); +} +#else +int __init oprofile_arch_init(struct oprofile_operations *ops) +{ + pr_info("oprofile: hardware counters not available\n"); + return -ENODEV; } +void oprofile_arch_exit(void) {} +#endif /* CONFIG_HW_PERF_EVENTS */ |