add option to use a busy waiting within the idle loop #1243
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mkroening
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Jun 5, 2024
- avoid using the halt instruction - CPU waits until another CPU change the ready queue - doesn't require wakeup IPIs
=> using busy waiting loop
…ate` Signed-off-by: Martin Kröning <[email protected]>
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Instead of the
hltinstruction, the idle loop use thepauseinstruction. => lower latency to wake up the core, but higher energy consumption.In addition, this PR support
monitor/mwaitinstructions. In this, the kernel hasn't to send an IPI to wakeup a core. The second optimization is that the kernels sends only an IPI, if the core is halted.