From 1b2bc75c1bde6581d2694cb3ed7fb06b69685008 Mon Sep 17 00:00:00 2001 From: Ralf Baechle Date: Tue, 23 Jun 2009 10:00:31 +0100 Subject: MIPS: Add arch generic CPU hotplug Each platform has to add support for CPU hotplugging itself by providing suitable definitions for the cpu_disable and cpu_die of the smp_ops methods and setting SYS_SUPPORTS_HOTPLUG_CPU. A platform should only set SYS_SUPPORTS_HOTPLUG_CPU once all it's smp_ops definitions have the necessary changes. This patch contains the changes to the dummy smp_ops definition for uni-processor systems. Parts of the code contributed by Cavium Inc. Signed-off-by: Ralf Baechle --- arch/mips/kernel/smp.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) (limited to 'arch/mips/kernel/smp.c') diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c index 58f4679bbd4..bc7d9b05e2f 100644 --- a/arch/mips/kernel/smp.c +++ b/arch/mips/kernel/smp.c @@ -45,7 +45,7 @@ #include #endif /* CONFIG_MIPS_MT_SMTC */ -static volatile cpumask_t cpu_callin_map; /* Bitmask of started secondaries */ +volatile cpumask_t cpu_callin_map; /* Bitmask of started secondaries */ int __cpu_number_map[NR_CPUS]; /* Map physical to logical */ int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */ @@ -201,6 +201,8 @@ void __devinit smp_prepare_boot_cpu(void) * and keep control until "cpu_online(cpu)" is set. Note: cpu is * physical, not logical. */ +static struct task_struct *cpu_idle_thread[NR_CPUS]; + int __cpuinit __cpu_up(unsigned int cpu) { struct task_struct *idle; @@ -210,9 +212,16 @@ int __cpuinit __cpu_up(unsigned int cpu) * The following code is purely to make sure * Linux can schedule processes on this slave. */ - idle = fork_idle(cpu); - if (IS_ERR(idle)) - panic(KERN_ERR "Fork failed for CPU %d", cpu); + if (!cpu_idle_thread[cpu]) { + idle = fork_idle(cpu); + cpu_idle_thread[cpu] = idle; + + if (IS_ERR(idle)) + panic(KERN_ERR "Fork failed for CPU %d", cpu); + } else { + idle = cpu_idle_thread[cpu]; + init_idle(idle, cpu); + } mp_ops->boot_secondary(cpu, idle); -- cgit v1.2.3