release/src-rt-6.x.4708/linux/linux-2.6.36/include/linux/task_io_accounting_ops.h

   1 /*
   2  * Task I/O accounting operations
   3  */
   4 #ifndef __TASK_IO_ACCOUNTING_OPS_INCLUDED
   5 #define __TASK_IO_ACCOUNTING_OPS_INCLUDED
   6
   7 #include <linux/sched.h>
   8
   9 #ifdef CONFIG_TASK_IO_ACCOUNTING
  10 static inline void task_io_account_read(size_t bytes)
  11 {
  12         current->ioac.read_bytes += bytes;
  13 }
  14
  15 /*
  16  * We approximate number of blocks, because we account bytes only.
  17  * A 'block' is 512 bytes
  18  */
  19 static inline unsigned long task_io_get_inblock(const struct task_struct *p)
  20 {
  21         return p->ioac.read_bytes >> 9;
  22 }
  23
  24 static inline void task_io_account_write(size_t bytes)
  25 {
  26         current->ioac.write_bytes += bytes;
  27 }
  28
  29 /*
  30  * We approximate number of blocks, because we account bytes only.
  31  * A 'block' is 512 bytes
  32  */
  33 static inline unsigned long task_io_get_oublock(const struct task_struct *p)
  34 {
  35         return p->ioac.write_bytes >> 9;
  36 }
  37
  38 static inline void task_io_account_cancelled_write(size_t bytes)
  39 {
  40         current->ioac.cancelled_write_bytes += bytes;
  41 }
  42
  43 static inline void task_io_accounting_init(struct task_io_accounting *ioac)
  44 {
  45         memset(ioac, 0, sizeof(*ioac));
  46 }
  47
  48 static inline void task_blk_io_accounting_add(struct task_io_accounting *dst,
  49                                                 struct task_io_accounting *src)
  50 {
  51         dst->read_bytes += src->read_bytes;
  52         dst->write_bytes += src->write_bytes;
  53         dst->cancelled_write_bytes += src->cancelled_write_bytes;
  54 }
  55
  56 #else
  57
  58 static inline void task_io_account_read(size_t bytes)
  59 {
  60 }
  61
  62 static inline unsigned long task_io_get_inblock(const struct task_struct *p)
  63 {
  64         return 0;
  65 }
  66
  67 static inline void task_io_account_write(size_t bytes)
  68 {
  69 }
  70
  71 static inline unsigned long task_io_get_oublock(const struct task_struct *p)
  72 {
  73         return 0;
  74 }
  75
  76 static inline void task_io_account_cancelled_write(size_t bytes)
  77 {
  78 }
  79
  80 static inline void task_io_accounting_init(struct task_io_accounting *ioac)
  81 {
  82 }
  83
  84 static inline void task_blk_io_accounting_add(struct task_io_accounting *dst,
  85                                                 struct task_io_accounting *src)
  86 {
  87 }
  88
  89 #endif /* CONFIG_TASK_IO_ACCOUNTING */
  90
  91 #ifdef CONFIG_TASK_XACCT
  92 static inline void task_chr_io_accounting_add(struct task_io_accounting *dst,
  93                                                 struct task_io_accounting *src)
  94 {
  95         dst->rchar += src->rchar;
  96         dst->wchar += src->wchar;
  97         dst->syscr += src->syscr;
  98         dst->syscw += src->syscw;
  99 }
 100 #else
 101 static inline void task_chr_io_accounting_add(struct task_io_accounting *dst,
 102                                                 struct task_io_accounting *src)
 103 {
 104 }
 105 #endif /* CONFIG_TASK_XACCT */
 106
 107 static inline void task_io_accounting_add(struct task_io_accounting *dst,
 108                                                 struct task_io_accounting *src)
 109 {
 110         task_chr_io_accounting_add(dst, src);
 111         task_blk_io_accounting_add(dst, src);
 112 }
 113 #endif /* __TASK_IO_ACCOUNTING_OPS_INCLUDED */