process.c File Reference

#include <stdio.h>
#include <string.h>
#include <os_config.h>
#include <sys/init.h>
#include <config/config_param.h>
#include <config/config_cparam.h>
#include <sys/arch.h>
#include <sys/ktypes.h>
#include <sys/ksched.h>
#include <sys/process.h>
#include <sys/mem.h>
#include <sys/queue.h>
#include <sys/ksemaphore.h>
#include <sys/msg.h>
#include <sys/shm.h>
#include <sys/decls.h>
#include <sys/stats.h>
#include <sys/timer.h>
#include <pthread.h>

Functions
void	idle_task (void)
pid_t	proc_create (unsigned int priority)
int	process_invalidate (process_struct *proc)
int	sys_process_status (pid_t pid, p_stat *ps)
pid_t	sys_get_currentPID (void)
void	process_block (queuep queue, unsigned int state)
void	process_unblock (queuep queue)
reent_t *	sys_get_reentrancy (void)
Variables
void *	kernel_sp
	Process Table.
pid_t	current_pid = -1
	Kernel Stack pointer.
pid_t	prev_pid = -1
	Currently executing processes' ID.
process_struct *	current_process = NULL
	ID of process executing immediately before a context switch.

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Detailed Description

This contains process management and thread management modules.

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Function Documentation

void idle_task (  void   )

This task is run when the system is idle. This task is initialized during system init and is always run with the least priority. Returns: Nothing Note: None

pid_t proc_create (  unsigned int  priority  )

Process creation primitive. Reserves a pid for the process. Initializes the process structure (except for the context) Places the process in the READY_Q. Parameters: priority  is the priority of the process Returns: PID of the new process. -1 on Error. Max. process exceeded. Note: None

void process_block (  queuep  queue, unsigned int  state )

Block the process. Place the process into the specified wait queue, change the state of the process and set the kernel flag to PROCESS_BLOCK. Call the process_scheduler Parameters: queue  is the queue where the process is enqueued. state is the state of the process in queue. Returns: Nothing Note: None

int process_invalidate (  process_struct *  proc  )

Remove the Process with pid. This is an internal proc that is called by sys_kill() and also by the schedulers to remove "DEAD" processes Parameters: proc  is the process structure of process to invalidate Returns: 0 on Success -1 on Error Note: None

void process_unblock (  queuep  queue  )

Unblock the first process in queue and place it onto the ready queue. Call the process_scheduler only if this is PRIO scheduling. This is because we do not want the current process to prematurely lose its time slice. Change the state of the process to PROC_READY Parameters: queue  is the queue where the process is enqueued. Returns: Nothing Note: None

pid_t sys_get_currentPID (  void   )

Return the PID of the currently running process context Returns: PID of the currently running process context. Note: None

reent_t* sys_get_reentrancy (  void   )

Return the kernel re-entrancy structure. This structure holds program level state information for the current process. Upon each context switch this structure is updated. to minimize the run-time efficiency, each application ELF file can query a pointer to this structure once and then use it for all subsequent state information queries. Parameters: None  Returns: Pointer to kernel re-entrancy structure Note: None

int sys_process_status (  pid_t  pid, p_stat *  ps )

Return the status of the process. Parameters: pid  is the Process ID of the process. ps is the structure where the status is returned. Returns: The status of the process is returned on ps If pid not an active process, ps->pid is assigned -1 Note: None

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