The Watch device deals with timer interrupts. More...
#include <device/watch.h>
Inheritance diagram for Watch: Collaboration diagram for Watch:Public Member Functions | |
| bool | windup (uint32_t us) |
| Windup / initialize. More... | |
| bool | prologue () override |
| Prologue of timer interrupts. More... | |
| void | epilogue () override |
| Epilogue of timer interrupts. More... | |
| uint32_t | interval () const |
| Retrieve the interrupt interval. More... | |
| void | activate () const |
| Activate the timer on this core. More... | |
| Public Member Functions inherited from Gate | |
The Watch device deals with timer interrupts.
Handles LAPIC::Timer interrupts, therefore managing the time slices and triggering a thread switch if necessary.
| bool Watch::windup | ( | uint32_t | us | ) |
Windup / initialize.
Assigns itself to the Plugbox and initializes the LAPIC::Timer in such a way that regular interrupts are triggered approx. every us microseconds when Watch::activate() is called. For this purpose, a suitable timer divisor is determined based on the timer frequency determined with LAPIC::Timer::ticks(). This timer divisor has to be as small as possible, but large enough to prevent the 32bit counter from overflowing.
| us | Desired interrupt interval in microseconds. |
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overridevirtual |
Prologue of timer interrupts.
i4stubs-all@lists.cs.fau.detrue if the Watch::epilogue should be executed.Implements Gate.
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overridevirtual |
Epilogue of timer interrupts.
Triggers the thread switch.
Reimplemented from Gate.
| uint32_t Watch::interval | ( | ) | const |
| void Watch::activate | ( | ) | const |
Activate the timer on this core.
The core local timer starts with the interval previously configured in windup(). To get timer interrupts on all cores, this method must be called once per core (however, it is sufficient to call windup only once since the APIC-Bus frequency is the same on each core).
