aboutsummaryrefslogtreecommitdiff
path: root/kernel/trace/trace_power.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/trace/trace_power.c')
-rw-r--r--kernel/trace/trace_power.c179
1 files changed, 179 insertions, 0 deletions
diff --git a/kernel/trace/trace_power.c b/kernel/trace/trace_power.c
new file mode 100644
index 00000000000..a7172a352f6
--- /dev/null
+++ b/kernel/trace/trace_power.c
@@ -0,0 +1,179 @@
+/*
+ * ring buffer based C-state tracer
+ *
+ * Arjan van de Ven <arjan@linux.intel.com>
+ * Copyright (C) 2008 Intel Corporation
+ *
+ * Much is borrowed from trace_boot.c which is
+ * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com>
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/debugfs.h>
+#include <linux/ftrace.h>
+#include <linux/kallsyms.h>
+#include <linux/module.h>
+
+#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_mask(cpu, cpu_possible_map)
+ 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);