[PATCH] kthread: convert stop_machine into a kthread (8bdd1d12) · Commits · 戴 / test

kernel/stop_machine.c

+11 −6

Original line number	Diff line number	Diff line
		@@ -4,6 +4,7 @@
		#include <linux/cpu.h>
		#include <linux/err.h>
		#include <linux/syscalls.h>
		#include <linux/kthread.h>
		#include <asm/atomic.h>
		#include <asm/semaphore.h>
		#include <asm/uaccess.h>
		@@ -25,13 +26,11 @@ static unsigned int stopmachine_num_threads;
		static atomic_t stopmachine_thread_ack;
		static DECLARE_MUTEX(stopmachine_mutex);

		static int stopmachine(void *cpu)
		static int stopmachine(void *unused)
		{
		int irqs_disabled = 0;
		int prepared = 0;

		set_cpus_allowed(current, cpumask_of_cpu((int)(long)cpu));

		/* Ack: we are alive */
		smp_mb(); /* Theoretically the ack = 0 might not be on this CPU yet. */
		atomic_inc(&stopmachine_thread_ack);
		@@ -85,7 +84,8 @@ static void stopmachine_set_state(enum stopmachine_state state)

		static int stop_machine(void)
		{
		int i, ret = 0;
		int ret = 0;
		unsigned int i;
		struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };

		/* One high-prio thread per cpu. We'll do this one. */
		@@ -96,11 +96,16 @@ static int stop_machine(void)
		stopmachine_state = STOPMACHINE_WAIT;

		for_each_online_cpu(i) {
		struct task_struct *tsk;
		if (i == raw_smp_processor_id())
		continue;
		ret = kernel_thread(stopmachine, (void *)(long)i,CLONE_KERNEL);
		if (ret < 0)
		tsk = kthread_create(stopmachine, NULL, "stopmachine");
		if (IS_ERR(tsk)) {
		ret = PTR_ERR(tsk);
		break;
		}
		kthread_bind(tsk, i);
		wake_up_process(tsk);
		stopmachine_num_threads++;
		}