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Diffstat (limited to 'kernel/trace/trace_clock.c')
-rw-r--r--kernel/trace/trace_clock.c42
1 files changed, 32 insertions, 10 deletions
diff --git a/kernel/trace/trace_clock.c b/kernel/trace/trace_clock.c
index 84a3a7ba072..57b67b1f24d 100644
--- a/kernel/trace/trace_clock.c
+++ b/kernel/trace/trace_clock.c
@@ -13,6 +13,7 @@
* Tracer plugins will chose a default from these clocks.
*/
#include <linux/spinlock.h>
+#include <linux/irqflags.h>
#include <linux/hardirq.h>
#include <linux/module.h>
#include <linux/percpu.h>
@@ -20,8 +21,6 @@
#include <linux/ktime.h>
#include <linux/trace_clock.h>
-#include "trace.h"
-
/*
* trace_clock_local(): the simplest and least coherent tracing clock.
*
@@ -31,22 +30,22 @@
u64 notrace trace_clock_local(void)
{
u64 clock;
- int resched;
/*
* sched_clock() is an architecture implemented, fast, scalable,
* lockless clock. It is not guaranteed to be coherent across
* CPUs, nor across CPU idle events.
*/
- resched = ftrace_preempt_disable();
+ preempt_disable_notrace();
clock = sched_clock();
- ftrace_preempt_enable(resched);
+ preempt_enable_notrace();
return clock;
}
+EXPORT_SYMBOL_GPL(trace_clock_local);
/*
- * trace_clock(): 'inbetween' trace clock. Not completely serialized,
+ * trace_clock(): 'between' trace clock. Not completely serialized,
* but not completely incorrect when crossing CPUs either.
*
* This is based on cpu_clock(), which will allow at most ~1 jiffy of
@@ -55,9 +54,20 @@ u64 notrace trace_clock_local(void)
*/
u64 notrace trace_clock(void)
{
- return cpu_clock(raw_smp_processor_id());
+ return local_clock();
}
+/*
+ * trace_jiffy_clock(): Simply use jiffies as a clock counter.
+ * Note that this use of jiffies_64 is not completely safe on
+ * 32-bit systems. But the window is tiny, and the effect if
+ * we are affected is that we will have an obviously bogus
+ * timestamp on a trace event - i.e. not life threatening.
+ */
+u64 notrace trace_clock_jiffies(void)
+{
+ return jiffies_64_to_clock_t(jiffies_64 - INITIAL_JIFFIES);
+}
/*
* trace_clock_global(): special globally coherent trace clock
@@ -83,10 +93,10 @@ u64 notrace trace_clock_global(void)
int this_cpu;
u64 now;
- raw_local_irq_save(flags);
+ local_irq_save(flags);
this_cpu = raw_smp_processor_id();
- now = cpu_clock(this_cpu);
+ now = sched_clock_cpu(this_cpu);
/*
* If in an NMI context then dont risk lockups and return the
* cpu_clock() time:
@@ -109,7 +119,19 @@ u64 notrace trace_clock_global(void)
arch_spin_unlock(&trace_clock_struct.lock);
out:
- raw_local_irq_restore(flags);
+ local_irq_restore(flags);
return now;
}
+
+static atomic64_t trace_counter;
+
+/*
+ * trace_clock_counter(): simply an atomic counter.
+ * Use the trace_counter "counter" for cases where you do not care
+ * about timings, but are interested in strict ordering.
+ */
+u64 notrace trace_clock_counter(void)
+{
+ return atomic64_add_return(1, &trace_counter);
+}