Busy loop: Difference between revisions
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(Created page with "{{Template:Stub}} A busy loop is a loop that continuously polls for an event. An alternative to this inefficient use of resources, for example, is to ask for an interrupt or ...") |
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== Definition == |
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A busy loop is a loop that continuously polls for an event. An alternative to this inefficient use of resources, for example, is to ask for an interrupt or sleep until the event occurs. |
A busy loop is a loop that continuously polls for an event. An alternative to this inefficient use of resources, for example, is to ask for an interrupt or sleep until the event occurs. |
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== Use Cases == |
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Busy loops, while expensive, can be used efficiently in some cases. You can implement a mutex like so, using a busy loop: |
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<source lang=c> |
<source lang=c> |
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int lock(mutex *mutex) { |
int lock(mutex *mutex) { |
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} |
} |
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</source> |
</source> |
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Busy loops can also be used to poll hardware, although it is inefficient. This is sometimes the only option for some hardware that does not support interrupts (bless it's heart). |
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Revision as of 22:37, 30 May 2021
Definition
A busy loop is a loop that continuously polls for an event. An alternative to this inefficient use of resources, for example, is to ask for an interrupt or sleep until the event occurs.
Use Cases
Busy loops, while expensive, can be used efficiently in some cases. You can implement a mutex like so, using a busy loop:
int lock(mutex *mutex) {
// Wait for the mutex to become free.
while(mutex->in_use);
mutex->in_use = 1;
return 0;
}
Busy loops can also be used to poll hardware, although it is inefficient. This is sometimes the only option for some hardware that does not support interrupts (bless it's heart).