kernel: Add CONFIG_SCHED_IPI_CASCADE (ada3c90f) · Commits · Wenxi XU / zephyr

kernel/Kconfig.smp

+12 −0

Original line number	Diff line number	Diff line
		@@ -63,6 +63,18 @@ config SCHED_IPI_SUPPORTED
		thread to take an interrupt, which can be arbitrarily far in the
		future).

		config SCHED_IPI_CASCADE
		bool "Use cascading IPIs to correct localized scheduling"
		depends on SCHED_CPU_MASK && !SCHED_CPU_MASK_PIN_ONLY
		default n
		help
		Threads that are preempted by a local thread (a thread that is
		restricted by its CPU mask to execute on a subset of all CPUs) may
		trigger additional IPIs when the preempted thread is of higher
		priority than a currently executing thread on another CPU. Although
		these cascading IPIs will ensure that the system will settle upon a
		valid set of high priority threads, it comes at a performance cost.

		config TRACE_SCHED_IPI
		bool "Test IPI"
		help

+10 −1

Original line number	Diff line number	Diff line
		@@ -931,12 +931,15 @@ void z_get_next_switch_handle(void interrupted)
		z_sched_usage_switch(new_thread);

		if (old_thread != new_thread) {
		uint8_t cpu_id;

		update_metairq_preempt(new_thread);
		z_sched_switch_spin(new_thread);
		arch_cohere_stacks(old_thread, interrupted, new_thread);

		_current_cpu->swap_ok = 0;
		new_thread->base.cpu = arch_curr_cpu()->id;
		cpu_id = arch_curr_cpu()->id;
		new_thread->base.cpu = cpu_id;
		set_current(new_thread);

		#ifdef CONFIG_TIMESLICING
		@@ -959,6 +962,12 @@ void z_get_next_switch_handle(void interrupted)
		* will not return into it.
		*/
		if (z_is_thread_queued(old_thread)) {
		#ifdef CONFIG_SCHED_IPI_CASCADE
		if ((new_thread->base.cpu_mask != -1) &&
		(old_thread->base.cpu_mask != BIT(cpu_id))) {
		flag_ipi(ipi_mask_create(old_thread));
		}
		#endif
		runq_add(old_thread);
		}
		}