A simple example of deadlock with threads can be the following situation, where we have 2 threads running:
Thread 1 takes lock on mutex for resource B
Thread 2 takes lock on mutex for resource A
Thread 1 tries to take lock on resource A, but Thread 2 has it
Thread 2 tries to take lock on resource B, but Thread 1 has it
At this point, thread 1 and 2 are deadlocked.Since neither can grab the locks they need, they will be descheduled by the kernel until one or the other gives up a mutex, which they cannot. Neither thread makes any progress
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chaominy
The necessary conditions for deadlock are:
1. At least one shared resource can only be used by one process at one time.
2. Hold and wait.
3. No Preemption.
4. Circular Wait. (Can be a circular among N processors, N > 1)
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bosher
And as a result, if we are able to guarantee that one of the conditions must not happen, we can be sure that our code does not have a deadlock.
A simple example of deadlock with threads can be the following situation, where we have 2 threads running:
Thread 1 takes lock on mutex for resource B
Thread 2 takes lock on mutex for resource A
Thread 1 tries to take lock on resource A, but Thread 2 has it
Thread 2 tries to take lock on resource B, but Thread 1 has it
At this point, thread 1 and 2 are deadlocked.Since neither can grab the locks they need, they will be descheduled by the kernel until one or the other gives up a mutex, which they cannot. Neither thread makes any progress
This comment was marked helpful 0 times.
The necessary conditions for deadlock are: 1. At least one shared resource can only be used by one process at one time. 2. Hold and wait. 3. No Preemption. 4. Circular Wait. (Can be a circular among N processors, N > 1)
This comment was marked helpful 0 times.
And as a result, if we are able to guarantee that one of the conditions must not happen, we can be sure that our code does not have a deadlock.
This comment was marked helpful 0 times.