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-rw-r--r--kernel/sched/clock.c36
1 files changed, 12 insertions, 24 deletions
diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index e086babe6c61..10c83e73837a 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -1,5 +1,5 @@
/*
- * sched_clock for unstable cpu clocks
+ * sched_clock() for unstable CPU clocks
*
* Copyright (C) 2008 Red Hat, Inc., Peter Zijlstra
*
@@ -11,7 +11,7 @@
* Guillaume Chazarain <guichaz@gmail.com>
*
*
- * What:
+ * What this file implements:
*
* cpu_clock(i) provides a fast (execution time) high resolution
* clock with bounded drift between CPUs. The value of cpu_clock(i)
@@ -26,11 +26,11 @@
* at 0 on boot (but people really shouldn't rely on that).
*
* cpu_clock(i) -- can be used from any context, including NMI.
- * local_clock() -- is cpu_clock() on the current cpu.
+ * local_clock() -- is cpu_clock() on the current CPU.
*
* sched_clock_cpu(i)
*
- * How:
+ * How it is implemented:
*
* The implementation either uses sched_clock() when
* !CONFIG_HAVE_UNSTABLE_SCHED_CLOCK, which means in that case the
@@ -52,19 +52,7 @@
* that is otherwise invisible (TSC gets stopped).
*
*/
-#include <linux/spinlock.h>
-#include <linux/hardirq.h>
-#include <linux/export.h>
-#include <linux/percpu.h>
-#include <linux/ktime.h>
-#include <linux/sched.h>
-#include <linux/nmi.h>
-#include <linux/sched/clock.h>
-#include <linux/static_key.h>
-#include <linux/workqueue.h>
-#include <linux/compiler.h>
-#include <linux/tick.h>
-#include <linux/init.h>
+#include "sched.h"
/*
* Scheduler clock - returns current time in nanosec units.
@@ -302,21 +290,21 @@ again:
* cmpxchg64 below only protects one readout.
*
* We must reread via sched_clock_local() in the retry case on
- * 32bit as an NMI could use sched_clock_local() via the
+ * 32-bit kernels as an NMI could use sched_clock_local() via the
* tracer and hit between the readout of
- * the low32bit and the high 32bit portion.
+ * the low 32-bit and the high 32-bit portion.
*/
this_clock = sched_clock_local(my_scd);
/*
- * We must enforce atomic readout on 32bit, otherwise the
- * update on the remote cpu can hit inbetween the readout of
- * the low32bit and the high 32bit portion.
+ * We must enforce atomic readout on 32-bit, otherwise the
+ * update on the remote CPU can hit inbetween the readout of
+ * the low 32-bit and the high 32-bit portion.
*/
remote_clock = cmpxchg64(&scd->clock, 0, 0);
#else
/*
- * On 64bit the read of [my]scd->clock is atomic versus the
- * update, so we can avoid the above 32bit dance.
+ * On 64-bit kernels the read of [my]scd->clock is atomic versus the
+ * update, so we can avoid the above 32-bit dance.
*/
sched_clock_local(my_scd);
again: