pub unsafe extern "C" fn k_sched_lock()Expand description
@brief Lock the scheduler.
This routine prevents the current thread from being preempted by another thread by instructing the scheduler to treat it as a cooperative thread. If the thread subsequently performs an operation that makes it unready, it will be context switched out in the normal manner. When the thread again becomes the current thread, its non-preemptible status is maintained.
This routine can be called recursively.
Owing to clever implementation details, scheduler locks are extremely fast for non-userspace threads (just one byte inc/decrement in the thread struct).
@note This works by elevating the thread priority temporarily to a cooperative priority, allowing cheap synchronization vs. other preemptible or cooperative threads running on the current CPU. It does not prevent preemption or asynchrony of other types. It does not prevent threads from running on other CPUs when CONFIG_SMP=y. It does not prevent interrupts from happening, nor does it prevent threads with MetaIRQ priorities from preempting the current thread. In general this is a historical API not well-suited to modern applications, use with care.