diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/Makefile | 1 | ||||
| -rw-r--r-- | kernel/cpu.c | 13 | ||||
| -rw-r--r-- | kernel/fork.c | 69 | ||||
| -rw-r--r-- | kernel/sched/Makefile | 2 | ||||
| -rw-r--r-- | kernel/sched/core.c | 2 | ||||
| -rw-r--r-- | kernel/smp.c | 27 | ||||
| -rw-r--r-- | kernel/smpboot.c | 62 | ||||
| -rw-r--r-- | kernel/smpboot.h | 18 |
8 files changed, 171 insertions, 23 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index cb41b9547c9..6c07f30fa9b 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -43,6 +43,7 @@ obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o obj-$(CONFIG_RT_MUTEX_TESTER) += rtmutex-tester.o obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o obj-$(CONFIG_SMP) += smp.o +obj-$(CONFIG_SMP) += smpboot.o ifneq ($(CONFIG_SMP),y) obj-y += up.o endif diff --git a/kernel/cpu.c b/kernel/cpu.c index 2060c6e5702..0e6353cf147 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -17,6 +17,8 @@ #include <linux/gfp.h> #include <linux/suspend.h> +#include "smpboot.h" + #ifdef CONFIG_SMP /* Serializes the updates to cpu_online_mask, cpu_present_mask */ static DEFINE_MUTEX(cpu_add_remove_lock); @@ -295,11 +297,19 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen) int ret, nr_calls = 0; void *hcpu = (void *)(long)cpu; unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; + struct task_struct *idle; if (cpu_online(cpu) || !cpu_present(cpu)) return -EINVAL; cpu_hotplug_begin(); + + idle = idle_thread_get(cpu); + if (IS_ERR(idle)) { + ret = PTR_ERR(idle); + goto out; + } + ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls); if (ret) { nr_calls--; @@ -309,7 +319,7 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen) } /* Arch-specific enabling code. */ - ret = __cpu_up(cpu); + ret = __cpu_up(cpu, idle); if (ret != 0) goto out_notify; BUG_ON(!cpu_online(cpu)); @@ -320,6 +330,7 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen) out_notify: if (ret != 0) __cpu_notify(CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL); +out: cpu_hotplug_done(); return ret; diff --git a/kernel/fork.c b/kernel/fork.c index 687a15d5624..9f9b296fa6d 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -112,32 +112,67 @@ int nr_processes(void) return total; } -#ifndef __HAVE_ARCH_TASK_STRUCT_ALLOCATOR -# define alloc_task_struct_node(node) \ - kmem_cache_alloc_node(task_struct_cachep, GFP_KERNEL, node) -# define free_task_struct(tsk) \ - kmem_cache_free(task_struct_cachep, (tsk)) +#ifndef CONFIG_ARCH_TASK_STRUCT_ALLOCATOR static struct kmem_cache *task_struct_cachep; + +static inline struct task_struct *alloc_task_struct_node(int node) +{ + return kmem_cache_alloc_node(task_struct_cachep, GFP_KERNEL, node); +} + +void __weak arch_release_task_struct(struct task_struct *tsk) { } + +static inline void free_task_struct(struct task_struct *tsk) +{ + arch_release_task_struct(tsk); + kmem_cache_free(task_struct_cachep, tsk); +} #endif -#ifndef __HAVE_ARCH_THREAD_INFO_ALLOCATOR +#ifndef CONFIG_ARCH_THREAD_INFO_ALLOCATOR +void __weak arch_release_thread_info(struct thread_info *ti) { } + +/* + * Allocate pages if THREAD_SIZE is >= PAGE_SIZE, otherwise use a + * kmemcache based allocator. + */ +# if THREAD_SIZE >= PAGE_SIZE static struct thread_info *alloc_thread_info_node(struct task_struct *tsk, int node) { -#ifdef CONFIG_DEBUG_STACK_USAGE - gfp_t mask = GFP_KERNEL | __GFP_ZERO; -#else - gfp_t mask = GFP_KERNEL; -#endif - struct page *page = alloc_pages_node(node, mask, THREAD_SIZE_ORDER); + struct page *page = alloc_pages_node(node, THREADINFO_GFP, + THREAD_SIZE_ORDER); return page ? page_address(page) : NULL; } static inline void free_thread_info(struct thread_info *ti) { + arch_release_thread_info(ti); free_pages((unsigned long)ti, THREAD_SIZE_ORDER); } +# else +static struct kmem_cache *thread_info_cache; + +static struct thread_info *alloc_thread_info_node(struct task_struct *tsk, + int node) +{ + return kmem_cache_alloc_node(thread_info_cache, THREADINFO_GFP, node); +} + +static void free_thread_info(struct thread_info *ti) +{ + arch_release_thread_info(ti); + kmem_cache_free(thread_info_cache, ti); +} + +void thread_info_cache_init(void) +{ + thread_info_cache = kmem_cache_create("thread_info", THREAD_SIZE, + THREAD_SIZE, 0, NULL); + BUG_ON(thread_info_cache == NULL); +} +# endif #endif /* SLAB cache for signal_struct structures (tsk->signal) */ @@ -204,17 +239,11 @@ void __put_task_struct(struct task_struct *tsk) } EXPORT_SYMBOL_GPL(__put_task_struct); -/* - * macro override instead of weak attribute alias, to workaround - * gcc 4.1.0 and 4.1.1 bugs with weak attribute and empty functions. - */ -#ifndef arch_task_cache_init -#define arch_task_cache_init() -#endif +void __init __weak arch_task_cache_init(void) { } void __init fork_init(unsigned long mempages) { -#ifndef __HAVE_ARCH_TASK_STRUCT_ALLOCATOR +#ifndef CONFIG_ARCH_TASK_STRUCT_ALLOCATOR #ifndef ARCH_MIN_TASKALIGN #define ARCH_MIN_TASKALIGN L1_CACHE_BYTES #endif diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile index 9a7dd35102a..173ea52f3af 100644 --- a/kernel/sched/Makefile +++ b/kernel/sched/Makefile @@ -16,5 +16,3 @@ obj-$(CONFIG_SMP) += cpupri.o obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o obj-$(CONFIG_SCHEDSTATS) += stats.o obj-$(CONFIG_SCHED_DEBUG) += debug.o - - diff --git a/kernel/sched/core.c b/kernel/sched/core.c index eb4131b8ad6..ea8a4769fea 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -83,6 +83,7 @@ #include "sched.h" #include "../workqueue_sched.h" +#include "../smpboot.h" #define CREATE_TRACE_POINTS #include <trace/events/sched.h> @@ -7062,6 +7063,7 @@ void __init sched_init(void) /* May be allocated at isolcpus cmdline parse time */ if (cpu_isolated_map == NULL) zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT); + idle_thread_set_boot_cpu(); #endif init_sched_fair_class(); diff --git a/kernel/smp.c b/kernel/smp.c index 2f8b10ecf75..d0ae5b24875 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -13,6 +13,8 @@ #include <linux/smp.h> #include <linux/cpu.h> +#include "smpboot.h" + #ifdef CONFIG_USE_GENERIC_SMP_HELPERS static struct { struct list_head queue; @@ -669,6 +671,8 @@ void __init smp_init(void) { unsigned int cpu; + idle_threads_init(); + /* FIXME: This should be done in userspace --RR */ for_each_present_cpu(cpu) { if (num_online_cpus() >= setup_max_cpus) @@ -791,3 +795,26 @@ void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info), } } EXPORT_SYMBOL(on_each_cpu_cond); + +static void do_nothing(void *unused) +{ +} + +/** + * kick_all_cpus_sync - Force all cpus out of idle + * + * Used to synchronize the update of pm_idle function pointer. It's + * called after the pointer is updated and returns after the dummy + * callback function has been executed on all cpus. The execution of + * the function can only happen on the remote cpus after they have + * left the idle function which had been called via pm_idle function + * pointer. So it's guaranteed that nothing uses the previous pointer + * anymore. + */ +void kick_all_cpus_sync(void) +{ + /* Make sure the change is visible before we kick the cpus */ + smp_mb(); + smp_call_function(do_nothing, NULL, 1); +} +EXPORT_SYMBOL_GPL(kick_all_cpus_sync); diff --git a/kernel/smpboot.c b/kernel/smpboot.c new file mode 100644 index 00000000000..e1a797e028a --- /dev/null +++ b/kernel/smpboot.c @@ -0,0 +1,62 @@ +/* + * Common SMP CPU bringup/teardown functions + */ +#include <linux/err.h> +#include <linux/smp.h> +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/percpu.h> + +#include "smpboot.h" + +#ifdef CONFIG_GENERIC_SMP_IDLE_THREAD +/* + * For the hotplug case we keep the task structs around and reuse + * them. + */ +static DEFINE_PER_CPU(struct task_struct *, idle_threads); + +struct task_struct * __cpuinit idle_thread_get(unsigned int cpu) +{ + struct task_struct *tsk = per_cpu(idle_threads, cpu); + + if (!tsk) + return ERR_PTR(-ENOMEM); + init_idle(tsk, cpu); + return tsk; +} + +void __init idle_thread_set_boot_cpu(void) +{ + per_cpu(idle_threads, smp_processor_id()) = current; +} + +static inline void idle_init(unsigned int cpu) +{ + struct task_struct *tsk = per_cpu(idle_threads, cpu); + + if (!tsk) { + tsk = fork_idle(cpu); + if (IS_ERR(tsk)) + pr_err("SMP: fork_idle() failed for CPU %u\n", cpu); + else + per_cpu(idle_threads, cpu) = tsk; + } +} + +/** + * idle_thread_init - Initialize the idle thread for a cpu + * @cpu: The cpu for which the idle thread should be initialized + * + * Creates the thread if it does not exist. + */ +void __init idle_threads_init(void) +{ + unsigned int cpu; + + for_each_possible_cpu(cpu) { + if (cpu != smp_processor_id()) + idle_init(cpu); + } +} +#endif diff --git a/kernel/smpboot.h b/kernel/smpboot.h new file mode 100644 index 00000000000..80c0acfb847 --- /dev/null +++ b/kernel/smpboot.h @@ -0,0 +1,18 @@ +#ifndef SMPBOOT_H +#define SMPBOOT_H + +struct task_struct; + +int smpboot_prepare(unsigned int cpu); + +#ifdef CONFIG_GENERIC_SMP_IDLE_THREAD +struct task_struct *idle_thread_get(unsigned int cpu); +void idle_thread_set_boot_cpu(void); +void idle_threads_init(void); +#else +static inline struct task_struct *idle_thread_get(unsigned int cpu) { return NULL; } +static inline void idle_thread_set_boot_cpu(void) { } +static inline void idle_threads_init(void) { } +#endif + +#endif |