sched/headers: sched/clock: Mark all functions 'notrace', remove CC_FLAGS_FTRACE build asymmetry

Mark all non-init functions in kernel/sched.c as 'notrace', instead of
turning them all off via CC_FLAGS_FTRACE.

This is going to allow the treatment of this file as any other scheduler
file, and it can be #include-ed in compound compilation units as well.

Signed-off-by: Ingo Molnar <[e-mail]>
Reviewed-by: Peter Zijlstra <[e-mail]>

kernel/sched/Makefile

···
 # SPDX-License-Identifier: GPL-2.0
-ifdef CONFIG_FUNCTION_TRACER
-CFLAGS_REMOVE_clock.o = $(CC_FLAGS_FTRACE)
-endif
 
 # The compilers are complaining about unused variables inside an if(0) scope
 # block. This is daft, shut them up.

kernel/sched/clock.c

···
  * This is default implementation.
  * Architectures and sub-architectures can override this.
  */
-unsigned long long __weak sched_clock(void)
+notrace unsigned long long __weak sched_clock(void)
 {
 	return (unsigned long long)(jiffies - INITIAL_JIFFIES)
 					* (NSEC_PER_SEC / HZ);
···
 
 static DEFINE_PER_CPU_SHARED_ALIGNED(struct sched_clock_data, sched_clock_data);
 
-static inline struct sched_clock_data *this_scd(void)
+notrace static inline struct sched_clock_data *this_scd(void)
 {
 	return this_cpu_ptr(&sched_clock_data);
 }
 
-static inline struct sched_clock_data *cpu_sdc(int cpu)
+notrace static inline struct sched_clock_data *cpu_sdc(int cpu)
 {
 	return &per_cpu(sched_clock_data, cpu);
 }
 
-int sched_clock_stable(void)
+notrace int sched_clock_stable(void)
 {
 	return static_branch_likely(&__sched_clock_stable);
 }
 
-static void __scd_stamp(struct sched_clock_data *scd)
+notrace static void __scd_stamp(struct sched_clock_data *scd)
 {
 	scd->tick_gtod = ktime_get_ns();
 	scd->tick_raw = sched_clock();
 }
 
-static void __set_sched_clock_stable(void)
+notrace static void __set_sched_clock_stable(void)
 {
 	struct sched_clock_data *scd;
 
···
  * The only way to fully avoid random clock jumps is to boot with:
  * "tsc=unstable".
  */
-static void __sched_clock_work(struct work_struct *work)
+notrace static void __sched_clock_work(struct work_struct *work)
 {
 	struct sched_clock_data *scd;
 	int cpu;
···
 
 static DECLARE_WORK(sched_clock_work, __sched_clock_work);
 
-static void __clear_sched_clock_stable(void)
+notrace static void __clear_sched_clock_stable(void)
 {
 	if (!sched_clock_stable())
 		return;
···
 	schedule_work(&sched_clock_work);
 }
 
-void clear_sched_clock_stable(void)
+notrace void clear_sched_clock_stable(void)
 {
 	__sched_clock_stable_early = 0;
 
···
 		__clear_sched_clock_stable();
 }
 
-static void __sched_clock_gtod_offset(void)
+notrace static void __sched_clock_gtod_offset(void)
 {
 	struct sched_clock_data *scd = this_scd();
 
···
  * min, max except they take wrapping into account
  */
 
-static inline u64 wrap_min(u64 x, u64 y)
+notrace static inline u64 wrap_min(u64 x, u64 y)
 {
 	return (s64)(x - y) < 0 ? x : y;
 }
 
-static inline u64 wrap_max(u64 x, u64 y)
+notrace static inline u64 wrap_max(u64 x, u64 y)
 {
 	return (s64)(x - y) > 0 ? x : y;
 }
···
  *  - filter out backward motion
  *  - use the GTOD tick value to create a window to filter crazy TSC values
  */
-static u64 sched_clock_local(struct sched_clock_data *scd)
+notrace static u64 sched_clock_local(struct sched_clock_data *scd)
 {
 	u64 now, clock, old_clock, min_clock, max_clock, gtod;
 	s64 delta;
···
 	return clock;
 }
 
-static u64 sched_clock_remote(struct sched_clock_data *scd)
+notrace static u64 sched_clock_remote(struct sched_clock_data *scd)
 {
 	struct sched_clock_data *my_scd = this_scd();
 	u64 this_clock, remote_clock;
···
  *
  * See cpu_clock().
  */
-u64 sched_clock_cpu(int cpu)
+notrace u64 sched_clock_cpu(int cpu)
 {
 	struct sched_clock_data *scd;
 	u64 clock;
···
 }
 EXPORT_SYMBOL_GPL(sched_clock_cpu);
 
-void sched_clock_tick(void)
+notrace void sched_clock_tick(void)
 {
 	struct sched_clock_data *scd;
 
···
 	sched_clock_local(scd);
 }
 
-void sched_clock_tick_stable(void)
+notrace void sched_clock_tick_stable(void)
 {
 	if (!sched_clock_stable())
 		return;
···
 /*
  * We are going deep-idle (irqs are disabled):
  */
-void sched_clock_idle_sleep_event(void)
+notrace void sched_clock_idle_sleep_event(void)
 {
 	sched_clock_cpu(smp_processor_id());
 }
···
 /*
  * We just idled; resync with ktime.
  */
-void sched_clock_idle_wakeup_event(void)
+notrace void sched_clock_idle_wakeup_event(void)
 {
 	unsigned long flags;
 
···
 	local_irq_enable();
 }
 
-u64 sched_clock_cpu(int cpu)
+notrace u64 sched_clock_cpu(int cpu)
 {
 	if (!static_branch_likely(&sched_clock_running))
 		return 0;
···
  * On bare metal this function should return the same as local_clock.
  * Architectures and sub-architectures can override this.
  */
-u64 __weak running_clock(void)
+notrace u64 __weak running_clock(void)
 {
 	return local_clock();
 }