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Diffstat (limited to 'kernel/old/include/procs.h')
| -rw-r--r-- | kernel/old/include/procs.h | 457 |
1 files changed, 457 insertions, 0 deletions
diff --git a/kernel/old/include/procs.h b/kernel/old/include/procs.h new file mode 100644 index 0000000..bc5b705 --- /dev/null +++ b/kernel/old/include/procs.h @@ -0,0 +1,457 @@ +/* +** @file procs.h +** +** @author CSCI-452 class of 20245 +** +** @brief Process-related declarations +*/ + +#ifndef PROCS_H_ +#define PROCS_H_ + +#include <common.h> + +/* +** General (C and/or assembly) definitions +*/ + +#ifndef ASM_SRC + +/* +** Start of C-only definitions +*/ + +/* +** Types +*/ + +/* +** Process states +*/ +enum state_e { + // pre-viable + STATE_UNUSED = 0, + STATE_NEW, + // runnable + STATE_READY, + STATE_RUNNING, + // runnable, but waiting for some event + STATE_SLEEPING, + STATE_BLOCKED, + STATE_WAITING, + // no longer runnable + STATE_KILLED, + STATE_ZOMBIE + // sentinel value + , + N_STATES +}; + +// these may be handy for checking general conditions of processes +// they depend on the order of the state names in the enum! +#define FIRST_VIABLE STATE_READY +#define FIRST_BLOCKED STATE_SLEEPING +#define LAST_VIABLE STATE_WAITING + +/* +** Process priorities are defined in <defs.h> +*/ + +/* +** Quantum lengths - values are number of clock ticks +*/ +enum quantum_e { QUANTUM_SHORT = 1, QUANTUM_STANDARD = 3, QUANTUM_LONG = 5 }; + +/* +** PID-related definitions +*/ +#define PID_INIT 1 +#define FIRST_USER_PID 2 + +/* +** Process context structure +** +** NOTE: the order of data members here depends on the +** register save code in isr_stubs.S!!!! +** +** This will be at the top of the user stack when we enter +** an ISR. In the case of a system call, it will be followed +** by the return address and the system call parameters. +*/ + +typedef struct context_s { + uint32_t ss; // pushed by isr_save + uint32_t gs; + uint32_t fs; + uint32_t es; + uint32_t ds; + uint32_t edi; + uint32_t esi; + uint32_t ebp; + uint32_t esp; + uint32_t ebx; + uint32_t edx; + uint32_t ecx; + uint32_t eax; + uint32_t vector; + uint32_t code; // pushed by isr_save or the hardware + uint32_t eip; // pushed by the hardware + uint32_t cs; + uint32_t eflags; +} context_t; + +#define SZ_CONTEXT sizeof(context_t) + +/* +** program section information for user processes +*/ + +typedef struct section_s { + uint_t length; // length, in some units + uint_t addr; // location, in some units +} section_t; + +// note: these correspond to the PT_LOAD sections found in +// an ELF file, not necessarily to text/data/bss +#define SECT_L1 0 +#define SECT_L2 1 +#define SECT_L3 2 +#define SECT_STACK 3 + +// total number of section table entries in our PCB +#define N_SECTS 4 +// number of those that can be loaded from an ELF module +#define N_LOADABLE 3 + +/* +** The process control block +** +** Fields are ordered by size to avoid padding +** +** Currently, this is 72 bytes long. It could be reduced to 64 (2^6) +** bytes by making the last four fields uint16_t types; that would +** divide nicely into 1024 bytes, giving 16 PCBs per 1/4 page of memory. +*/ + +typedef struct pcb_s { + // four-byte fields + // start with these four bytes, for easy access in assembly + context_t *context; // pointer to context save area on stack + + // VM information + pde_t *pdir; // page directory for this process + section_t sects[N_SECTS]; // per-section memory information + + // queue linkage + struct pcb_s *next; // next PCB in queue + + // process state information + struct pcb_s *parent; // pointer to PCB of our parent process + uint32_t wakeup; // wakeup time, for sleeping processes + int32_t exit_status; // termination status, for parent's use + + // these things may not need to be four bytes + uint_t pid; // PID of this process + enum state_e state; // process' current state + enum priority_e priority; // process priority level + uint_t ticks; // remaining ticks in this time slice + +} pcb_t; + +#define SZ_PCB sizeof(pcb_t) + +/* +** PCB queue structure (opaque to the rest of the kernel) +*/ +typedef struct pcb_queue_s *pcb_queue_t; + +/* +** Queue ordering methods +*/ +enum pcb_queue_order_e { + O_FIFO, + O_PRIO, + O_PID, + O_WAKEUP + // sentinel + , + N_ORDERINGS +}; +#define O_FIRST_STYLE O_FIFO +#define O_LAST_STYLE O_WAKEUP + +/* +** Globals +*/ + +// public-facing queue handles +extern pcb_queue_t pcb_freelist; +extern pcb_queue_t ready; +extern pcb_queue_t waiting; +extern pcb_queue_t sleeping; +extern pcb_queue_t zombie; +extern pcb_queue_t sioread; + +// pointer to the currently-running process +extern pcb_t *current; + +// the process table +extern pcb_t ptable[N_PROCS]; + +// next available PID +extern uint_t next_pid; + +// pointer to the PCB for the 'init' process +extern pcb_t *init_pcb; + +// table of state name strings +extern const char state_str[N_STATES][4]; + +// table of priority name strings +extern const char prio_str[N_PRIOS][5]; + +// table of queue ordering name strings +extern const char ord_str[N_ORDERINGS][5]; + +/* +** Prototypes +*/ + +/** +** Name: pcb_init +** +** Initialization for the Process module. +*/ +void pcb_init(void); + +/** +** Name: pcb_alloc +** +** Allocate a PCB from the list of free PCBs. +** +** @param pcb Pointer to a pcb_t * where the PCB pointer will be returned. +** +** @return status of the allocation attempt +*/ +int pcb_alloc(pcb_t **pcb); + +/** +** Name: pcb_free +** +** Return a PCB to the list of free PCBs. +** +** @param pcb Pointer to the PCB to be deallocated. +*/ +void pcb_free(pcb_t *pcb); + +/** +** Name: pcb_zombify +** +** Turn the indicated process into a Zombie. This function +** does most of the real work for exit() and kill() calls. +** Is also called from the scheduler and dispatcher. +** +** @param pcb Pointer to the newly-undead PCB +*/ +void pcb_zombify(register pcb_t *victim); + +/** +** Name: pcb_cleanup +** +** Reclaim a process' data structures +** +** @param pcb The PCB to reclaim +*/ +void pcb_cleanup(pcb_t *pcb); + +/** +** Name: pcb_find_pid +** +** Locate the PCB for the process with the specified PID +** +** @param pid The PID to be located +** +** @return Pointer to the PCB, or NULL +*/ +pcb_t *pcb_find_pid(uint_t pid); + +/** +** Name: pcb_find_ppid +** +** Locate the PCB for the process with the specified parent +** +** @param pid The PID to be located +** +** @return Pointer to the PCB, or NULL +*/ +pcb_t *pcb_find_ppid(uint_t pid); + +/** +** Name: pcb_queue_reset +** +** Initialize a PCB queue. +** +** @param queue[out] The queue to be initialized +** @param order[in] The desired ordering for the queue +** +** @return status of the init request +*/ +int pcb_queue_reset(pcb_queue_t queue, enum pcb_queue_order_e style); + +/** +** Name: pcb_queue_empty +** +** Determine whether a queue is empty. Essentially just a wrapper +** for the PCB_QUEUE_EMPTY() macro, for use outside this module. +** +** @param[in] queue The queue to check +** +** @return true if the queue is empty, else false +*/ +bool_t pcb_queue_empty(pcb_queue_t queue); + +/** +** Name: pcb_queue_length +** +** Return the count of elements in the specified queue. +** +** @param[in] queue The queue to check +** +** @return the count (0 if the queue is empty) +*/ +uint_t pcb_queue_length(const pcb_queue_t queue); + +/** +** Name: pcb_queue_insert +** +** Inserts a PCB into the indicated queue. +** +** @param queue[in,out] The queue to be used +** @param pcb[in] The PCB to be inserted +** +** @return status of the insertion request +*/ +int pcb_queue_insert(pcb_queue_t queue, pcb_t *pcb); + +/** +** Name: pcb_queue_peek +** +** Return the first PCB from the indicated queue, but don't +** remove it from the queue +** +** @param queue[in] The queue to be used +** +** @return the PCB pointer, or NULL if the queue is empty +*/ +pcb_t *pcb_queue_peek(const pcb_queue_t queue); + +/** +** Name: pcb_queue_remove +** +** Remove the first PCB from the indicated queue. +** +** @param queue[in,out] The queue to be used +** @param pcb[out] Pointer to where the PCB pointer will be saved +** +** @return status of the removal request +*/ +int pcb_queue_remove(pcb_queue_t queue, pcb_t **pcb); + +/** +** Name: pcb_queue_remove_this +** +** Remove the specified PCB from the indicated queue. +** +** @param queue[in,out] The queue to be used +** @param pcb[in] Pointer to the PCB to be removed +** +** @return status of the removal request +*/ +int pcb_queue_remove_this(pcb_queue_t queue, pcb_t *pcb); + +/* +** Scheduler routines +*/ + +/** +** schedule(pcb) +** +** Schedule the supplied process +** +** @param pcb Pointer to the PCB of the process to be scheduled +*/ +void schedule(pcb_t *pcb); + +/** +** dispatch() +** +** Select the next process to receive the CPU +*/ +void dispatch(void); + +/* +** Debugging/tracing routines +*/ + +/** +** Name: ctx_dump +** +** Dumps the contents of this process context to the console +** +** @param msg[in] An optional message to print before the dump +** @param c[in] The context to dump out +*/ +void ctx_dump(const char *msg, register context_t *c); + +/** +** Name: ctx_dump_all +** +** dump the process context for all active processes +** +** @param msg[in] Optional message to print +*/ +void ctx_dump_all(const char *msg); + +/** +** Name: pcb_dump +** +** Dumps the contents of this PCB to the console +** +** @param msg[in] An optional message to print before the dump +** @param p[in] The PCB to dump +** @param all[in] Dump all the contents? +*/ +void pcb_dump(const char *msg, register pcb_t *p, bool_t all); + +/** +** Name: pcb_queue_dump +** +** Dump the contents of the specified queue to the console +** +** @param msg[in] An optional message to print before the dump +** @param queue[in] The queue to dump +** @param contents[in] Also dump (some) contents? +*/ +void pcb_queue_dump(const char *msg, pcb_queue_t queue, bool_t contents); + +/** +** Name: ptable_dump +** +** dump the contents of the "active processes" table +** +** @param msg[in] Optional message to print +** @param all[in] Dump all or only part of the relevant data +*/ +void ptable_dump(const char *msg, bool_t all); + +/** +** Name: ptable_dump_counts +** +** Prints basic information about the process table (number of +** entries, number with each process state, etc.). +*/ +void ptable_dump_counts(void); + +#endif /* !ASM_SRC */ + +#endif |