xv6-cs450/proc.h
2006-07-20 09:07:53 +00:00

76 lines
1.9 KiB
C

/*
* p->mem:
* text
* original data and bss
* fixed-size stack
* expandable heap
*/
/*
* segments in proc->gdt
*/
#define SEG_KCODE 1 // kernel code
#define SEG_KDATA 2 // kernel data+stack
#define SEG_UCODE 3
#define SEG_UDATA 4
#define SEG_TSS 5 // this process's task state
#define NSEGS 6
struct jmpbuf {
// saved registers for kernel context switches
// don't need to save all the fs etc. registers because
// they are constant across kernel contexts
// save all the regular registers so we don't care which are caller save
// don't save eax because that's the return register
// layout known to setjmp.S
int ebx;
int ecx;
int edx;
int esi;
int edi;
int esp;
int ebp;
int eip;
};
enum proc_state { UNUSED, EMBRYO, SLEEPING, RUNNABLE, RUNNING, ZOMBIE };
struct proc{
char *mem; // start of process's physical memory
uint sz; // total size of mem, including kernel stack
char *kstack; // kernel stack, separate from mem so it doesn't move
enum proc_state state;
enum proc_state newstate; // desired state after swtch()
struct spinlock *mtx; // mutex for condition variable
int pid;
int ppid;
void *chan; // sleep
int killed;
struct fd *fds[NOFILE];
struct taskstate ts; // only to give cpu address of kernel stack
struct segdesc gdt[NSEGS];
uint esp; // kernel stack pointer
uint ebp; // kernel frame pointer
struct jmpbuf jmpbuf;
struct trapframe *tf; // points into kstack, used to find user regs
};
extern struct proc proc[];
extern struct proc *curproc[NCPU]; // can be NULL if no proc running.
// XXX move curproc into cpu structure?
#define MPSTACK 512
struct cpu {
uchar apicid; // Local APIC ID
struct jmpbuf jmpbuf;
char mpstack[MPSTACK]; // per-cpu start-up stack, only used to get into main()
struct proc *lastproc; // last proc scheduled on this cpu (never NULL)
int nlock; // # of locks currently held
};
extern struct cpu cpus[NCPU];
extern int ncpu;