zephyr/arch/arm64
Henri Xavier 45af717a66 arch/arm64: Implement ASID support in ARM64 MMU
Improves context-switch performance.

TLB invalidation and the nG bit are used conservatively. This could
be improved in future work.

Tested with tests/benchmarks/sched_userspace:

BEFORE:
```
Swapping  2 threads: 161562583 cyc & 1000000 rounds ->   1615 ns per ctx
Swapping  8 threads: 161569289 cyc & 1000000 rounds ->   1615 ns per ctx
Swapping 16 threads: 161649163 cyc & 1000000 rounds ->   1616 ns per ctx
Swapping 32 threads: 163487880 cyc & 1000000 rounds ->   1634 ns per ctx
```

AFTER:
```
Swapping  2 threads: 18129207 cyc & 1000000 rounds ->    181 ns per ctx
Swapping  8 threads: 49702891 cyc & 1000000 rounds ->    497 ns per ctx
Swapping 16 threads: 55898650 cyc & 1000000 rounds ->    558 ns per ctx
Swapping 32 threads: 58059704 cyc & 1000000 rounds ->    580 ns per ctx
```

Signed-off-by: Henri Xavier <datacomos@huawei.com>
2022-12-13 17:21:11 +09:00
..
core arch/arm64: Implement ASID support in ARM64 MMU 2022-12-13 17:21:11 +09:00
include arch/arm64: Implement ASID support in ARM64 MMU 2022-12-13 17:21:11 +09:00
CMakeLists.txt
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