perf(x86_64): skip APIC probe on uhyve

[n0toose]

• Skip memory probes, use default address directly on Uhyve.
• Checking whether the processor supports x2apic in init_x2apic goes against the component's own conventions.
• We need a local APIC, but IO-APIC is not supported.
• Show more relevant info/warning messages.
• Fix minor formatting issue that shows "0x0x" prefix.

Fixes #1352

[n0toose]

As pointed out in #1352 (comment), a manual skip of x2apic causes an error (adding that it appears both under QEMU and Uhyve). I don't currently believe it is relevant to my changes.

[github-actions]

Benchmark Results

Benchmark	Current: 9d15052	Previous: 376b966	Performance Ratio
startup_benchmark Build Time	108.61 s	110.37 s	0.98
startup_benchmark File Size	0.91 MB	0.90 MB	1.00
Startup Time - 1 core	0.91 s (±0.03 s)	0.93 s (±0.03 s)	0.99
Startup Time - 2 cores	0.90 s (±0.03 s)	0.93 s (±0.03 s)	0.96
Startup Time - 4 cores	0.92 s (±0.04 s)	0.93 s (±0.03 s)	0.99
multithreaded_benchmark Build Time	112.07 s	114.11 s	0.98
multithreaded_benchmark File Size	1.01 MB	1.01 MB	1.00
Multithreaded Pi Efficiency - 2 Threads	87.89 % (±9.00 %)	87.54 % (±7.72 %)	1.00
Multithreaded Pi Efficiency - 4 Threads	43.50 % (±3.24 %)	43.85 % (±3.71 %)	0.99
Multithreaded Pi Efficiency - 8 Threads	24.88 % (±2.03 %)	25.11 % (±2.07 %)	0.99
micro_benchmarks Build Time	106.56 s	106.92 s	1.00
micro_benchmarks File Size	1.01 MB	1.01 MB	1.00
Scheduling time - 1 thread	68.69 ticks (±5.22 ticks)	67.03 ticks (±3.54 ticks)	1.02
Scheduling time - 2 threads	38.19 ticks (±4.69 ticks)	38.31 ticks (±5.49 ticks)	1.00
Micro - Time for syscall (getpid)	3.20 ticks (±0.50 ticks)	2.98 ticks (±0.45 ticks)	1.07
Memcpy speed - (built_in) block size 4096	82695.54 MByte/s (±57207.20 MByte/s)	78287.67 MByte/s (±54207.29 MByte/s)	1.06
Memcpy speed - (built_in) block size 1048576	42700.92 MByte/s (±29572.30 MByte/s)	42758.95 MByte/s (±29603.37 MByte/s)	1.00
Memcpy speed - (built_in) block size 16777216	28953.71 MByte/s (±23785.36 MByte/s)	28796.76 MByte/s (±23654.74 MByte/s)	1.01
Memset speed - (built_in) block size 4096	82745.72 MByte/s (±57244.21 MByte/s)	78337.85 MByte/s (±54246.52 MByte/s)	1.06
Memset speed - (built_in) block size 1048576	42936.08 MByte/s (±29733.57 MByte/s)	43001.55 MByte/s (±29767.07 MByte/s)	1.00
Memset speed - (built_in) block size 16777216	29713.37 MByte/s (±24222.04 MByte/s)	29553.13 MByte/s (±24095.41 MByte/s)	1.01
Memcpy speed - (rust) block size 4096	72695.87 MByte/s (±50564.54 MByte/s)	70495.32 MByte/s (±49405.95 MByte/s)	1.03
Memcpy speed - (rust) block size 1048576	42717.91 MByte/s (±29581.54 MByte/s)	42856.55 MByte/s (±29682.27 MByte/s)	1.00
Memcpy speed - (rust) block size 16777216	28794.14 MByte/s (±23621.65 MByte/s)	28900.71 MByte/s (±23739.86 MByte/s)	1.00
Memset speed - (rust) block size 4096	72838.08 MByte/s (±50644.01 MByte/s)	69943.60 MByte/s (±49128.48 MByte/s)	1.04
Memset speed - (rust) block size 1048576	42918.33 MByte/s (±29718.03 MByte/s)	43095.53 MByte/s (±29843.91 MByte/s)	1.00
Memset speed - (rust) block size 16777216	29543.48 MByte/s (±24052.22 MByte/s)	29647.15 MByte/s (±24171.90 MByte/s)	1.00
alloc_benchmarks Build Time	104.71 s	105.40 s	0.99
alloc_benchmarks File Size	0.97 MB	0.97 MB	1.00
Allocations - Allocation success	100.00 %	100.00 %	1
Allocations - Deallocation success	70.01 % (±0.27 %)	70.03 % (±0.30 %)	1.00
Allocations - Pre-fail Allocations	100.00 %	100.00 %	1
Allocations - Average Allocation time	12238.43 Ticks (±206.43 Ticks)	12298.03 Ticks (±230.53 Ticks)	1.00
Allocations - Average Allocation time (no fail)	12238.43 Ticks (±206.43 Ticks)	12298.03 Ticks (±230.53 Ticks)	1.00
Allocations - Average Deallocation time	714.40 Ticks (±78.86 Ticks)	722.17 Ticks (±103.75 Ticks)	0.99
mutex_benchmark Build Time	104.83 s	105.06 s	1.00
mutex_benchmark File Size	1.02 MB	1.02 MB	1.00
Mutex Stress Test Average Time per Iteration - 1 Threads	12.72 ns (±0.87 ns)	12.74 ns (±0.74 ns)	1.00
Mutex Stress Test Average Time per Iteration - 2 Threads	14.54 ns (±1.04 ns)	14.80 ns (±1.47 ns)	0.98

This comment was automatically generated by workflow using github-action-benchmark.

[mkroening]

Could you split this up into several commits to ease review of separate changes? :)

I am not too convinced about the log changes. Not being able to find APIC via ACPI or MP is expected for certain machines (such as Uhyve). I don't think this warrants a warning. In what kind of cases are the logs useful in practice?

[mkroening]

Do I understand correctly that this is improving the performance and not fixing a problem?

[n0toose]

Do I understand correctly that this is improving the performance and not fixing a problem?

I considered performing checks "that will not go anywhere" in the Uhyve environment to be a problem/bug, but I understand why the fix: might be misleading. Sorry.

To answer your question: Yes. To the best extend that I am aware of, I don't find that the previous checks are necessary within Uhyve (as far as its main branch is concerned) for Uhyve to work. This change removes this "small freeze effect"-feeling when launching Uhyve.

[mkroening]

All right, I have further separated the refactoring from the first commit. I think you missed adding a condition in application_processor_init. I wonder why this caused no problems, though. It should have, as far as I understand.

Are you okay with my changes? :) c2159c8..9d15052