arch/sh/kernel/process.c

   1 #include <linux/mm.h>
   2 #include <linux/kernel.h>
   3 #include <linux/slab.h>
   4 #include <linux/sched.h>
   5
   6 struct kmem_cache *task_xstate_cachep = NULL;
   7 unsigned int xstate_size;
   8
   9 /*
  10  * this gets called so that we can store lazy state into memory and copy the
  11  * current task into the new thread.
  12  */
  13 int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
  14 {
  15 #ifdef CONFIG_SUPERH32
  16         unlazy_fpu(src, task_pt_regs(src));
  17 #endif
  18         *dst = *src;
  19
  20         if (src->thread.xstate) {
  21                 dst->thread.xstate = kmem_cache_alloc(task_xstate_cachep,
  22                                                       GFP_KERNEL);
  23                 if (!dst->thread.xstate)
  24                         return -ENOMEM;
  25                 memcpy(dst->thread.xstate, src->thread.xstate, xstate_size);
  26         }
  27
  28         return 0;
  29 }
  30
  31 void free_thread_xstate(struct task_struct *tsk)
  32 {
  33         if (tsk->thread.xstate) {
  34                 kmem_cache_free(task_xstate_cachep, tsk->thread.xstate);
  35                 tsk->thread.xstate = NULL;
  36         }
  37 }
  38
  39 #if THREAD_SHIFT < PAGE_SHIFT
  40 static struct kmem_cache *thread_info_cache;
  41
  42 struct thread_info *alloc_thread_info_node(struct task_struct *tsk, int node)
  43 {
  44         struct thread_info *ti;
  45 #ifdef CONFIG_DEBUG_STACK_USAGE
  46         gfp_t mask = GFP_KERNEL | __GFP_ZERO;
  47 #else
  48         gfp_t mask = GFP_KERNEL;
  49 #endif
  50
  51         ti = kmem_cache_alloc_node(thread_info_cache, mask, node);
  52         return ti;
  53 }
  54
  55 void free_thread_info(struct thread_info *ti)
  56 {
  57         free_thread_xstate(ti->task);
  58         kmem_cache_free(thread_info_cache, ti);
  59 }
  60
  61 void thread_info_cache_init(void)
  62 {
  63         thread_info_cache = kmem_cache_create("thread_info", THREAD_SIZE,
  64                                               THREAD_SIZE, SLAB_PANIC, NULL);
  65 }
  66 #else
  67 struct thread_info *alloc_thread_info_node(struct task_struct *tsk, int node)
  68 {
  69 #ifdef CONFIG_DEBUG_STACK_USAGE
  70         gfp_t mask = GFP_KERNEL | __GFP_ZERO;
  71 #else
  72         gfp_t mask = GFP_KERNEL;
  73 #endif
  74         struct page *page = alloc_pages_node(node, mask, THREAD_SIZE_ORDER);
  75
  76         return page ? page_address(page) : NULL;
  77 }
  78
  79 void free_thread_info(struct thread_info *ti)
  80 {
  81         free_thread_xstate(ti->task);
  82         free_pages((unsigned long)ti, THREAD_SIZE_ORDER);
  83 }
  84 #endif /* THREAD_SHIFT < PAGE_SHIFT */
  85
  86 void arch_task_cache_init(void)
  87 {
  88         if (!xstate_size)
  89                 return;
  90
  91         task_xstate_cachep = kmem_cache_create("task_xstate", xstate_size,
  92                                                __alignof__(union thread_xstate),
  93                                                SLAB_PANIC | SLAB_NOTRACK, NULL);
  94 }
  95
  96 #ifdef CONFIG_SH_FPU_EMU
  97 # define HAVE_SOFTFP    1
  98 #else
  99 # define HAVE_SOFTFP    0
 100 #endif
 101
 102 void __cpuinit init_thread_xstate(void)
 103 {
 104         if (boot_cpu_data.flags & CPU_HAS_FPU)
 105                 xstate_size = sizeof(struct sh_fpu_hard_struct);
 106         else if (HAVE_SOFTFP)
 107                 xstate_size = sizeof(struct sh_fpu_soft_struct);
 108         else
 109                 xstate_size = 0;
 110 }