code:prele - ikarishinjieva/unixV6-code-analyze-chs GitHub Wiki

7875

7876 /* Unlock a pipe.

7877 * If WANT bit is on,

7878 * wakeup.

7879 * This routine is also used

7880 * to ulock inodes in general.

7881 */

7882 prele(ip)

7883 int *ip;

7884 {

7885 register *rp;

7886

7887 rp = ip;

7888 rp->i_flag =& ~ILOCK;

清除锁标志

7889 if(rp->i_flag&IWANT) {

7890 rp->i_flag =& ~IWANT;

7891 wakeup(rp);

7892 }

如果有进程在等待该INODE，则

清除IWANT标志

唤醒因等待该块而睡眠的进程

参看睡眠原因

7893 }

7894 /* ------------------------- */

7895

7896

7897

7898

7899