text: #ifndef _PROFILE_H
  #define _PROFILE_H
  
  #include <minix/type.h>
  #include <sys/types.h>
  
  /*
   * Types relating to system profiling.  Types are supplied for both
   * statistical profiling and call profiling.
   */
  
  #  define PROF_START       0    /* start statistical profiling */
  #  define PROF_STOP        1    /* stop statistical profiling */
  
  #define PROF_RTC	0 /* RTC based profiling */
  #define PROF_NMI	1 /* NMI based profiling, profiles kernel too */
  
  /* Info struct to be copied to from kernel to user program. */
  struct sprof_info_s {
    int mem_used;
    int total_samples;
    int idle_samples;
    int system_samples;
    int user_samples;
  };
  
  /* What a profiling sample looks like (used for sizeof()). */
  struct sprof_sample {
  	endpoint_t	proc;
  	void *		pc;
  };
  
  struct sprof_proc {
  	endpoint_t	proc;
  	char		name[PROC_NAME_LEN];
  };
  
  #  define PROF_GET         2    /* get call profiling tables */
  #  define PROF_RESET       3    /* reset call profiling tables */
  
  /* Hash table size in each profiled process is table size + index size.
   *
   * Table size = CPROF_TABLE_SIZE * (CPROF_CPATH_MAX_LEN + 16).
   * Index size = CPROF_INDEX_SIZE * 4;
   *
   * Making CPROF_CPATH_MAX_LEN too small may cause call path overruns.
   * Making CPROF_TABLE_SIZE too small may cause table overruns.
   * 
   * There are some restrictions: processes in the boot image are loaded
   * below 16 MB and the kernel is loaded in lower memory (below 640 kB). The
   * latter is reason to use a different size for the kernel table.
   */
  #define CPROF_TABLE_SIZE_OTHER	3000	/* nr of slots in hash table */
  #define CPROF_TABLE_SIZE_KERNEL	1500	/* kernel has a smaller table */
  #define CPROF_CPATH_MAX_LEN	256	/* len of cpath string field: */
  					/* MUST BE MULTIPLE OF WORDSIZE */
  
  #define CPROF_INDEX_SIZE	(10*1024)/* size of index to hash table */
  #define CPROF_STACK_SIZE	24	/* size of call stack */
  #define CPROF_PROCNAME_LEN	8	/* len of proc name field */
  
  #define CPROF_CPATH_OVERRUN	0x1	/* call path overrun */
  #define CPROF_STACK_OVERRUN	0x2	/* call stack overrun */
  #define CPROF_TABLE_OVERRUN	0x4	/* hash table overrun */
  
  #define CPROF_ANNOUNCE_OTHER	1	/* processes announce their profiling
  					 * data on n-th entry of procentry */
  #define CPROF_ACCOUNCE_KERNEL	10000	/* kernel announces not directly */
  
  /* Prototype for function called by procentry to get size of table. */
  int profile_get_tbl_size(void);
  /* Prototype for function called by procentry to get announce number. */
  int profile_get_announce(void);
  /* Prototype for function called by procentry to announce control struct
   * and table locations to the kernel. */
  void profile_register(void *ctl_ptr, void *tbl_ptr);
  
  /* Info struct to be copied from kernel to user program. */
  struct cprof_info_s {
    int mem_used;
    int err;
  };
  
  /* Data structures for control structure and profiling data table in the
   * in the profiled processes. 
   */
  struct cprof_ctl_s {
    int reset;				/* kernel sets to have table reset */
    int slots_used;			/* proc writes nr slots used in table */
    int err;				/* proc writes errors that occurred */
  };
  
  struct cprof_tbl_s {
    struct cprof_tbl_s *next;		/* next in chain */
    char cpath[CPROF_CPATH_MAX_LEN];	/* string with call path */
    int calls;				/* nr of executions of path */
    u64_t cycles;				/* execution time of path, in cycles */
  };
  
  int sprofile(int action, int size, int freq, int type, void *ctl_ptr,
  	void *mem_ptr);
  
  int cprofile(int action, int size, void *ctl_ptr, void *mem_ptr);
  
  #endif /* PROFILE_H */
  
  