程序調度程序在哪裡執行？我可以追踪它嗎？

程序調度程序在使用者空間是否“可見”？可以用ps看嗎？也許它是核心執行緒之一？如果是，它是怎麼稱呼的？我怎樣才能“看到”它？

它不作為單獨的執行緒或模組存在，而是作為函式實現

好的，但是這個函式是如何、在哪里以及以何種方式執行的呢？有沒有辦法跟踪它並看到它？

正如什麼是 Linux 中的程序調度程序中所解釋的那樣？調度器是一個核函式，__schedule；它不會顯示為單獨的執行緒或程序。

函式註釋解釋了它是如何執行的：

* The main means of driving the scheduler and thus entering this function are:
*
*   1. Explicit blocking: mutex, semaphore, waitqueue, etc.
*
*   2. TIF_NEED_RESCHED flag is checked on interrupt and userspace return
*      paths. For example, see arch/x86/entry_64.S.
*
*      To drive preemption between tasks, the scheduler sets the flag in timer
*      interrupt handler scheduler_tick().
*
*   3. Wakeups don't really cause entry into schedule(). They add a
*      task to the run-queue and that's it.
*
*      Now, if the new task added to the run-queue preempts the current
*      task, then the wakeup sets TIF_NEED_RESCHED and schedule() gets
*      called on the nearest possible occasion:
*
*       - If the kernel is preemptible (CONFIG_PREEMPTION=y):
*
*         - in syscall or exception context, at the next outmost
*           preempt_enable(). (this might be as soon as the wake_up()'s
*           spin_unlock()!)
*
*         - in IRQ context, return from interrupt-handler to
*           preemptible context
*
*       - If the kernel is not preemptible (CONFIG_PREEMPTION is not set)
*         then at the next:
*
*          - cond_resched() call
*          - explicit schedule() call
*          - return from syscall or exception to user-space
*          - return from interrupt-handler to user-space

功能無法追踪；它的儀器被禁用（參見notrace其聲明中的條目）。

引用自：https://unix.stackexchange.com/questions/699279