static int sbprof_tb_open(struct inode *inode, struct file *filp)
{
int minor;
- int err = 0;
- lock_kernel();
minor = iminor(inode);
- if (minor != 0) {
- err = -ENODEV;
- goto out;
- }
+ if (minor != 0)
+ return -ENODEV;
- if (xchg(&sbp.open, SB_OPENING) != SB_CLOSED) {
- err = -EBUSY;
- goto out;
- }
+ if (xchg(&sbp.open, SB_OPENING) != SB_CLOSED)
+ return -EBUSY;
memset(&sbp, 0, sizeof(struct sbprof_tb));
sbp.sbprof_tbbuf = vmalloc(MAX_TBSAMPLE_BYTES);
if (!sbp.sbprof_tbbuf) {
- err = -ENOMEM;
- goto out;
+ sbp.open = SB_CLOSED;
+ wmb();
+ return -ENOMEM;
}
+
memset(sbp.sbprof_tbbuf, 0, MAX_TBSAMPLE_BYTES);
init_waitqueue_head(&sbp.tb_sync);
init_waitqueue_head(&sbp.tb_read);
mutex_init(&sbp.lock);
sbp.open = SB_OPEN;
+ wmb();
- out:
- unlock_kernel();
- return err;
+ return 0;
}
static int sbprof_tb_release(struct inode *inode, struct file *filp)
int minor;
minor = iminor(inode);
- if (minor != 0 || !sbp.open)
+ if (minor != 0 || sbp.open != SB_CLOSED)
return -ENODEV;
mutex_lock(&sbp.lock);
sbprof_zbprof_stop();
vfree(sbp.sbprof_tbbuf);
- sbp.open = 0;
+ sbp.open = SB_CLOSED;
+ wmb();
mutex_unlock(&sbp.lock);
}
tb_dev = dev;
- sbp.open = 0;
+ sbp.open = SB_CLOSED;
+ wmb();
tb_period = zbbus_mhz * 10000LL;
pr_info(DEVNAME ": initialized - tb_period = %lld\n",
(long long) tb_period);