SNIP_CLASSIC_OS_FIGURE_Figure_7_20

Figure 7.20: A deadlock situation caused by interference, the high priority Task spins indefinitely because the low priority Task has occupied the spinlock. In such cases the second GetSpinlock call will return with an error. A user can protect a Task against such a situation by , for example, rapping the spinlock with SuspendAllInterrupts, so that it cannot be interfered by other Tasks. The OS can do this automatically for the caller - see OsSpinlockLockMethod. A second deadlock situation can be created by nested spinlocks calls, as illustrated in