kernel/sysproc.c

1#include "types.h"2#include "riscv.h"3#include "defs.h"4#include "param.h"5#include "memlayout.h"6#include "spinlock.h"7#include "proc.h"8#include "vm.h"910uint6411sys_exit(void)12{13  int n;14  argint(0, &n);15  kexit(n);16  return 0;  // not reached17}1819uint6420sys_getpid(void)21{22  return myproc()->pid;23}2425uint6426sys_fork(void)27{28  return kfork();29}3031uint6432sys_wait(void)33{34  uint64 p;35  argaddr(0, &p);36  return kwait(p);37}3839uint6440sys_sbrk(void)41{42  uint64 addr;43  int t;44  int n;4546  argint(0, &n);47  argint(1, &t);48  addr = myproc()->sz;4950  if(t == SBRK_EAGER || n < 0) {51    if(growproc(n) < 0) {52      return -1;53    }54  } else {55    // Lazily allocate memory for this process: increase its memory56    // size but don't allocate memory. If the processes uses the57    // memory, vmfault() will allocate it.58    if(addr + n < addr)59      return -1;60    if(addr + n > TRAPFRAME)61      return -1;62    myproc()->sz += n;63  }64  return addr;65}6667uint6468sys_pause(void)69{70  int n;71  uint ticks0;7273  argint(0, &n);74  if(n < 0)75    n = 0;76  acquire(&tickslock);77  ticks0 = ticks;78  while(ticks - ticks0 < n){79    if(killed(myproc())){80      release(&tickslock);81      return -1;82    }83    sleep(&ticks, &tickslock);84  }85  release(&tickslock);86  return 0;87}8889uint6490sys_kill(void)91{92  int pid;9394  argint(0, &pid);95  return kkill(pid);96}9798// return how many clock tick interrupts have occurred99// since start.100uint64101sys_uptime(void)102{103  uint xticks;104105  acquire(&tickslock);106  xticks = ticks;107  release(&tickslock);108  return xticks;109}110