blktrace_api.h

   1 #ifndef BLKTRACEAPI_H
   2 #define BLKTRACEAPI_H
   3
   4 #include <asm/types.h>
   5
   6 /*
   7  * Trace categories
   8  */
   9 enum {
  10         BLK_TC_READ     = 1 << 0,       /* reads */
  11         BLK_TC_WRITE    = 1 << 1,       /* writes */
  12         BLK_TC_BARRIER  = 1 << 2,       /* barrier */
  13         BLK_TC_SYNC     = 1 << 3,       /* barrier */
  14         BLK_TC_QUEUE    = 1 << 4,       /* queueing/merging */
  15         BLK_TC_REQUEUE  = 1 << 5,       /* requeueing */
  16         BLK_TC_ISSUE    = 1 << 6,       /* issue */
  17         BLK_TC_COMPLETE = 1 << 7,       /* completions */
  18         BLK_TC_FS       = 1 << 8,       /* fs requests */
  19         BLK_TC_PC       = 1 << 9,       /* pc requests */
  20
  21         BLK_TC_END      = 1 << 15,      /* only 16-bits, reminder */
  22 };
  23
  24 #define BLK_TC_SHIFT            (16)
  25 #define BLK_TC_ACT(act)         ((act) << BLK_TC_SHIFT)
  26
  27 /*
  28  * Basic trace actions
  29  */
  30 enum {
  31         __BLK_TA_QUEUE = 1,             /* queued */
  32         __BLK_TA_BACKMERGE,             /* back merged to existing rq */
  33         __BLK_TA_FRONTMERGE,            /* front merge to existing rq */
  34         __BLK_TA_GETRQ,                 /* allocated new request */
  35         __BLK_TA_SLEEPRQ,               /* sleeping on rq allocation */
  36         __BLK_TA_REQUEUE,               /* request requeued */
  37         __BLK_TA_ISSUE,                 /* sent to driver */
  38         __BLK_TA_COMPLETE,              /* completed by driver */
  39 };
  40
  41 /*
  42  * Trace actions in full. Additionally, read or write is masked
  43  */
  44 #define BLK_TA_QUEUE            (__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE))
  45 #define BLK_TA_BACKMERGE        (__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE))
  46 #define BLK_TA_FRONTMERGE       (__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE))
  47 #define BLK_TA_GETRQ            (__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE))
  48 #define BLK_TA_SLEEPRQ          (__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE))
  49 #define BLK_TA_REQUEUE          (__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE))
  50 #define BLK_TA_ISSUE            (__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE))
  51 #define BLK_TA_COMPLETE         (__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE))
  52
  53 #define BLK_IO_TRACE_MAGIC      0x65617400
  54 #define BLK_IO_TRACE_VERSION    0x04
  55
  56 /*
  57  * The trace itself
  58  */
  59 struct blk_io_trace {
  60         __u32 magic;            /* MAGIC << 8 | version */
  61         __u32 sequence;         /* event number */
  62         __u64 time;             /* in microseconds */
  63         __u64 sector;           /* disk offset */
  64         __u32 bytes;            /* transfer length */
  65         __u32 action;           /* what happened */
  66         __u32 pid;              /* who did it */
  67         __u32 cpu;              /* on what cpu did it happen */
  68         __u16 error;            /* completion error */
  69         __u16 pdu_len;          /* length of data after this trace */
  70         char  comm[16];         /* task command name (TASK_COMM_LEN) */
  71 };
  72
  73 /*
  74  * User setup structure passed with BLKSTARTTRACE
  75  */
  76 struct blk_user_trace_setup {
  77         char name[32];                  /* output */
  78         __u16 act_mask;                 /* input */
  79         __u32 buf_size;                 /* input */
  80         __u32 buf_nr;                   /* input */
  81 };
  82
  83 #define BLKSTARTTRACE _IOWR(0x12,115,struct blk_user_trace_setup)
  84 #define BLKSTOPTRACE _IO(0x12,116)
  85
  86 #endif