tick/sched: Remove nohz disabled special case in cputime fetch

Even when nohz is not runtime enabled, the dynticks idle cputime accounting
can run and the common idle cputime accessors are still relevant.

Remove the nohz disabled special case accordingly.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Tested-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Link: https://patch.msgid.link/20260508131647.43868-9-frederic@kernel.org

Author: Frederic Weisbecker

kernel/time/tick-sched.c

@@ -795,9 +795,6 @@ static u64 get_cpu_sleep_time_us(int cpu, enum cpu_usage_stat idx,
 	ktime_t now, idle;
 	unsigned int seq;
 
-	if (!tick_nohz_active)
-		return -1;
-
 	now = ktime_get();
 	if (last_update_time)
 		*last_update_time = ktime_to_us(now);
@@ -839,7 +836,7 @@ static u64 get_cpu_sleep_time_us(int cpu, enum cpu_usage_stat idx,
  * This time is measured via accounting rather than sampling,
  * and is as accurate as ktime_get() is.
  *
- * Return: -1 if NOHZ is not enabled, else total idle time of the @cpu
+ * Return: -1 if generic vtime is enabled, else total idle time of the @cpu
  */
 u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time)
 {
@@ -863,7 +860,7 @@ EXPORT_SYMBOL_GPL(get_cpu_idle_time_us);
  * This time is measured via accounting rather than sampling,
  * and is as accurate as ktime_get() is.
  *
- * Return: -1 if NOHZ is not enabled, else total iowait time of @cpu
+ * Return: -1 if generic vtime is enabled, else total iowait time of @cpu
  */
 u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time)
 {