Pileus Git - ~andy/linux/blob - kernel/events/internal.h

   1 #ifndef _KERNEL_EVENTS_INTERNAL_H
   2 #define _KERNEL_EVENTS_INTERNAL_H
   3
   4 #include <linux/hardirq.h>
   5 #include <linux/uaccess.h>
   6
   7 /* Buffer handling */
   8
   9 #define RING_BUFFER_WRITABLE            0x01
  10
  11 struct ring_buffer {
  12         atomic_t                        refcount;
  13         struct rcu_head                 rcu_head;
  14 #ifdef CONFIG_PERF_USE_VMALLOC
  15         struct work_struct              work;
  16         int                             page_order;     /* allocation order  */
  17 #endif
  18         int                             nr_pages;       /* nr of data pages  */
  19         int                             overwrite;      /* can overwrite itself */
  20
  21         atomic_t                        poll;           /* POLL_ for wakeups */
  22
  23         local_t                         head;           /* write position    */
  24         local_t                         nest;           /* nested writers    */
  25         local_t                         events;         /* event limit       */
  26         local_t                         wakeup;         /* wakeup stamp      */
  27         local_t                         lost;           /* nr records lost   */
  28
  29         long                            watermark;      /* wakeup watermark  */
  30         /* poll crap */
  31         spinlock_t                      event_lock;
  32         struct list_head                event_list;
  33
  34         int                             mmap_locked;
  35         struct user_struct              *mmap_user;
  36
  37         struct perf_event_mmap_page     *user_page;
  38         void                            *data_pages[0];
  39 };
  40
  41 extern void rb_free(struct ring_buffer *rb);
  42 extern struct ring_buffer *
  43 rb_alloc(int nr_pages, long watermark, int cpu, int flags);
  44 extern void perf_event_wakeup(struct perf_event *event);
  45
  46 extern void
  47 perf_event_header__init_id(struct perf_event_header *header,
  48                            struct perf_sample_data *data,
  49                            struct perf_event *event);
  50 extern void
  51 perf_event__output_id_sample(struct perf_event *event,
  52                              struct perf_output_handle *handle,
  53                              struct perf_sample_data *sample);
  54
  55 extern struct page *
  56 perf_mmap_to_page(struct ring_buffer *rb, unsigned long pgoff);
  57
  58 #ifdef CONFIG_PERF_USE_VMALLOC
  59 /*
  60  * Back perf_mmap() with vmalloc memory.
  61  *
  62  * Required for architectures that have d-cache aliasing issues.
  63  */
  64
  65 static inline int page_order(struct ring_buffer *rb)
  66 {
  67         return rb->page_order;
  68 }
  69
  70 #else
  71
  72 static inline int page_order(struct ring_buffer *rb)
  73 {
  74         return 0;
  75 }
  76 #endif
  77
  78 static inline unsigned long perf_data_size(struct ring_buffer *rb)
  79 {
  80         return rb->nr_pages << (PAGE_SHIFT + page_order(rb));
  81 }
  82
  83 #define DEFINE_OUTPUT_COPY(func_name, memcpy_func)                      \
  84 static inline unsigned int                                              \
  85 func_name(struct perf_output_handle *handle,                            \
  86           const void *buf, unsigned int len)                            \
  87 {                                                                       \
  88         unsigned long size, written;                                    \
  89                                                                         \
  90         do {                                                            \
  91                 size = min_t(unsigned long, handle->size, len);         \
  92                                                                         \
  93                 written = memcpy_func(handle->addr, buf, size);         \
  94                                                                         \
  95                 len -= written;                                         \
  96                 handle->addr += written;                                \
  97                 buf += written;                                         \
  98                 handle->size -= written;                                \
  99                 if (!handle->size) {                                    \
 100                         struct ring_buffer *rb = handle->rb;            \
 101                                                                         \
 102                         handle->page++;                                 \
 103                         handle->page &= rb->nr_pages - 1;               \
 104                         handle->addr = rb->data_pages[handle->page];    \
 105                         handle->size = PAGE_SIZE << page_order(rb);     \
 106                 }                                                       \
 107         } while (len && written == size);                               \
 108                                                                         \
 109         return len;                                                     \
 110 }
 111
 112 static inline int memcpy_common(void *dst, const void *src, size_t n)
 113 {
 114         memcpy(dst, src, n);
 115         return n;
 116 }
 117
 118 DEFINE_OUTPUT_COPY(__output_copy, memcpy_common)
 119
 120 #define MEMCPY_SKIP(dst, src, n) (n)
 121
 122 DEFINE_OUTPUT_COPY(__output_skip, MEMCPY_SKIP)
 123
 124 #ifndef arch_perf_out_copy_user
 125 #define arch_perf_out_copy_user __copy_from_user_inatomic
 126 #endif
 127
 128 DEFINE_OUTPUT_COPY(__output_copy_user, arch_perf_out_copy_user)
 129
 130 /* Callchain handling */
 131 extern struct perf_callchain_entry *
 132 perf_callchain(struct perf_event *event, struct pt_regs *regs);
 133 extern int get_callchain_buffers(void);
 134 extern void put_callchain_buffers(void);
 135
 136 static inline int get_recursion_context(int *recursion)
 137 {
 138         int rctx;
 139
 140         if (in_nmi())
 141                 rctx = 3;
 142         else if (in_irq())
 143                 rctx = 2;
 144         else if (in_softirq())
 145                 rctx = 1;
 146         else
 147                 rctx = 0;
 148
 149         if (recursion[rctx])
 150                 return -1;
 151
 152         recursion[rctx]++;
 153         barrier();
 154
 155         return rctx;
 156 }
 157
 158 static inline void put_recursion_context(int *recursion, int rctx)
 159 {
 160         barrier();
 161         recursion[rctx]--;
 162 }
 163
 164 #ifdef CONFIG_HAVE_PERF_USER_STACK_DUMP
 165 static inline bool arch_perf_have_user_stack_dump(void)
 166 {
 167         return true;
 168 }
 169
 170 #define perf_user_stack_pointer(regs) user_stack_pointer(regs)
 171 #else
 172 static inline bool arch_perf_have_user_stack_dump(void)
 173 {
 174         return false;
 175 }
 176
 177 #define perf_user_stack_pointer(regs) 0
 178 #endif /* CONFIG_HAVE_PERF_USER_STACK_DUMP */
 179
 180 #endif /* _KERNEL_EVENTS_INTERNAL_H */