minix/kernel/profile.c

/*
 * This file contains several functions and variables used for system
 * profiling.
 *
 * Statistical Profiling:
 *   The interrupt handler for profiling clock. 
 *
 * Call Profiling:
 *   The table used for profiling data and a function to get its size.
 *
 *   The function used by kernelspace processes to register the locations
 *   of their control struct and profiling table.
 *
 * Changes:
 *   14 Aug, 2006   Created, (Rogier Meurs)
 */

#include <minix/config.h>

#include <minix/profile.h>
#include <minix/portio.h>
#include "kernel.h"
#include "profile.h"
#include "proc.h"

#if SPROFILE

#include <string.h>

/* Function prototype for the profiling clock handler. */ 
FORWARD _PROTOTYPE( int profile_clock_handler, (irq_hook_t *hook) );

/* A hook for the profiling clock interrupt handler. */
PRIVATE irq_hook_t profile_clock_hook;

/*===========================================================================*
 *			init_profile_clock				     *
 *===========================================================================*/
PUBLIC void init_profile_clock(u32_t freq)
{
  int r, irq;

  intr_disable();

  if((irq = arch_init_profile_clock(freq)) >= 0) {
	/* Register interrupt handler for statistical system profiling.  */
	profile_clock_hook.proc_nr_e = CLOCK;
	put_irq_handler(&profile_clock_hook, irq, profile_clock_handler);
	enable_irq(&profile_clock_hook);
  }

  intr_enable();
}

/*===========================================================================*
 *			profile_clock_stop				     *
 *===========================================================================*/
PUBLIC void stop_profile_clock()
{
  intr_disable();
  arch_stop_profile_clock();
  intr_enable();

  /* Unregister interrupt handler. */
  disable_irq(&profile_clock_hook);
  rm_irq_handler(&profile_clock_hook);
}

/*===========================================================================*
 *			profile_clock_handler                           *
 *===========================================================================*/
PRIVATE int profile_clock_handler(hook)
irq_hook_t *hook;
{
/* This executes on every tick of the CMOS timer. */

  /* Are we profiling, and profiling memory not full? */
  if (!sprofiling || sprof_info.mem_used == -1) return (1);

  /* Check if enough memory available before writing sample. */
  if (sprof_info.mem_used + sizeof(sprof_info) > sprof_mem_size) {
	sprof_info.mem_used = -1;
	return(1);
  }

  /* All is OK */

  /* Idle process? */
  if (priv(proc_ptr)->s_proc_nr == IDLE) {
	sprof_info.idle_samples++;
  } else
  /* Runnable system process? */
  if (priv(proc_ptr)->s_flags & SYS_PROC && !proc_ptr->p_rts_flags) {
	/* Note: k_reenter is always 0 here. */

	/* Store sample (process name and program counter). */
	data_copy(SYSTEM, (vir_bytes) proc_ptr->p_name,
		sprof_ep, sprof_data_addr_vir + sprof_info.mem_used,
		strlen(proc_ptr->p_name));

	data_copy(SYSTEM, (vir_bytes) &proc_ptr->p_reg.pc, sprof_ep,
		(vir_bytes) (sprof_data_addr_vir + sprof_info.mem_used +
					sizeof(proc_ptr->p_name)),
		(vir_bytes) sizeof(proc_ptr->p_reg.pc));

	sprof_info.mem_used += sizeof(sprof_sample);

	sprof_info.system_samples++;
  } else {
	/* User process. */
	sprof_info.user_samples++;
  }
  
  sprof_info.total_samples++;

  /* Acknowledge interrupt if necessary. */
  arch_ack_profile_clock();

  return(1);                                    /* reenable interrupts */
}

#endif /* SPROFILE */


/* 
 * The following variables and functions are used by the procentry/
 * procentry syslib functions when linked with kernelspace processes.
 * For userspace processes, the same variables and function are defined
 * elsewhere. This enables different functionality and variable sizes,
 * which is needed is a few cases.
 */

/* A small table is declared for the kernelspace processes. */
struct cprof_tbl_s cprof_tbl[CPROF_TABLE_SIZE_KERNEL];

/* Function that returns table size. */
PUBLIC int profile_get_tbl_size(void)
{
  return CPROF_TABLE_SIZE_KERNEL;
}

/* Function that returns on which execution of procentry to announce. */
PUBLIC int profile_get_announce(void)
{
  return CPROF_ACCOUNCE_KERNEL;
}

/*
 * The kernel "announces" its control struct and table locations
 * to itself through this function.
 */
PUBLIC void profile_register(ctl_ptr, tbl_ptr)
void *ctl_ptr;
void *tbl_ptr;
{
  int proc_nr;
  vir_bytes vir_dst;
  struct proc *rp;                          

  if(cprof_procs_no >= NR_SYS_PROCS)
	return;

  /* Store process name, control struct, table locations. */
  rp = proc_addr(SYSTEM);

  cprof_proc_info[cprof_procs_no].endpt = rp->p_endpoint;
  cprof_proc_info[cprof_procs_no].name = rp->p_name;
  cprof_proc_info[cprof_procs_no].ctl_v = (vir_bytes) ctl_ptr;
  cprof_proc_info[cprof_procs_no].buf_v = (vir_bytes) tbl_ptr;

  cprof_procs_no++;
}