Commit a0f11dff authored by Wang Yuanheng's avatar Wang Yuanheng Committed by guzitao
Browse files

sw64: fix secondary cpu bring up bug 

Sunway inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IB73UR



--------------------------------

If smp_rcb->ready is set after secondary cpu receives reset
signal, the secondary cpu may fail to wake up.

Signed-off-by: default avatarWang Yuanheng <wangyuanheng@wxiat.com>
Reviewed-by: default avatarHe Sheng <hesheng@wxiat.com>
Signed-off-by: default avatarGu Zitao <guzitao@wxiat.com>
parent 13e8251f

arch/sw_64/kernel/smp.c

+3 −8
Original line number Diff line number Diff line
@@ -139,6 +139,9 @@ static int secondary_cpu_start(int cpuid, struct task_struct *idle) 


	set_secondary_ready(cpuid);



	/* send reset signal */

	reset_cpu(cpuid);



	/* Wait 10 seconds for secondary cpu.  */

	timeout = jiffies + 10*HZ;

	while (time_before(jiffies, timeout)) {
@@ -318,7 +321,6 @@ int vt_cpu_up(unsigned int cpu, struct task_struct *tidle) 
	wmb();

	smp_rcb->ready = 0;

	/* irq must be disabled before reset vCPU */

	reset_cpu(cpu);

	smp_boot_one_cpu(cpu, tidle);



	return cpu_online(cpu) ? 0 : -EIO;
@@ -340,13 +342,6 @@ int __cpu_up(unsigned int cpu, struct task_struct *tidle) 
	/* send wake up signal */

	send_wakeup_interrupt(cpu);

#endif

	/* send reset signal */

	if (is_in_host()) {

		reset_cpu(cpu);

	} else {

		while (1)

			cpu_relax();

	}

	smp_boot_one_cpu(cpu, tidle);



#ifdef CONFIG_SUBARCH_C3B