/* * ring buffer based C-state tracer * * Arjan van de Ven * Copyright (C) 2008 Intel Corporation * * Much is borrowed from trace_boot.c which is * Copyright (C) 2008 Frederic Weisbecker * */ #include #include #include #include #include #include "trace.h" static struct trace_array *power_trace; static int __read_mostly trace_power_enabled; static void start_power_trace(struct trace_array *tr) { trace_power_enabled = 1; } static void stop_power_trace(struct trace_array *tr) { trace_power_enabled = 0; } static int power_trace_init(struct trace_array *tr) { int cpu; power_trace = tr; trace_power_enabled = 1; for_each_cpu(cpu, cpu_possible_mask) tracing_reset(tr, cpu); return 0; } static enum print_line_t power_print_line(struct trace_iterator *iter) { int ret = 0; struct trace_entry *entry = iter->ent; struct trace_power *field ; struct power_trace *it; struct trace_seq *s = &iter->seq; struct timespec stamp; struct timespec duration; trace_assign_type(field, entry); it = &field->state_data; stamp = ktime_to_timespec(it->stamp); duration = ktime_to_timespec(ktime_sub(it->end, it->stamp)); if (entry->type == TRACE_POWER) { if (it->type == POWER_CSTATE) ret = trace_seq_printf(s, "[%5ld.%09ld] CSTATE: Going to C%i on cpu %i for %ld.%09ld\n", stamp.tv_sec, stamp.tv_nsec, it->state, iter->cpu, duration.tv_sec, duration.tv_nsec); if (it->type == POWER_PSTATE) ret = trace_seq_printf(s, "[%5ld.%09ld] PSTATE: Going to P%i on cpu %i\n", stamp.tv_sec, stamp.tv_nsec, it->state, iter->cpu); if (!ret) return TRACE_TYPE_PARTIAL_LINE; return TRACE_TYPE_HANDLED; } return TRACE_TYPE_UNHANDLED; } static struct tracer power_tracer __read_mostly = { .name = "power", .init = power_trace_init, .start = start_power_trace, .stop = stop_power_trace, .reset = stop_power_trace, .print_line = power_print_line, }; static int init_power_trace(void) { return register_tracer(&power_tracer); } device_initcall(init_power_trace); void trace_power_start(struct power_trace *it, unsigned int type, unsigned int level) { if (!trace_power_enabled) return; memset(it, 0, sizeof(struct power_trace)); it->state = level; it->type = type; it->stamp = ktime_get(); } EXPORT_SYMBOL_GPL(trace_power_start); void trace_power_end(struct power_trace *it) { struct ring_buffer_event *event; struct trace_power *entry; struct trace_array_cpu *data; unsigned long irq_flags; struct trace_array *tr = power_trace; if (!trace_power_enabled) return; preempt_disable(); it->end = ktime_get(); data = tr->data[smp_processor_id()]; event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), &irq_flags); if (!event) goto out; entry = ring_buffer_event_data(event); tracing_generic_entry_update(&entry->ent, 0, 0); entry->ent.type = TRACE_POWER; entry->state_data = *it; ring_buffer_unlock_commit(tr->buffer, event, irq_flags); trace_wake_up(); out: preempt_enable(); } EXPORT_SYMBOL_GPL(trace_power_end); void trace_power_mark(struct power_trace *it, unsigned int type, unsigned int level) { struct ring_buffer_event *event; struct trace_power *entry; struct trace_array_cpu *data; unsigned long irq_flags; struct trace_array *tr = power_trace; if (!trace_power_enabled) return; memset(it, 0, sizeof(struct power_trace)); it->state = level; it->type = type; it->stamp = ktime_get(); preempt_disable(); it->end = it->stamp; data = tr->data[smp_processor_id()]; event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), &irq_flags); if (!event) goto out; entry = ring_buffer_event_data(event); tracing_generic_entry_update(&entry->ent, 0, 0); entry->ent.type = TRACE_POWER; entry->state_data = *it; ring_buffer_unlock_commit(tr->buffer, event, irq_flags); trace_wake_up(); out: preempt_enable(); } EXPORT_SYMBOL_GPL(trace_power_mark);