Fix CPU frequency estimation on riscv #1549
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https://github.com/google/benchmark/actions/runs/4217605263/jobs/7332317281#step:6:24 .. looks like a bit cleverer #defines are needed to avoid the lambda capture that's unnecessary. |
It has been resolved. It looks like only clang++ complains about this. By the way, I think clang is actually used for the workflow |
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looks good.. just that one thing i'd like you to move back please, then check CI, then i can merge it :) |
I think |
sure. if they're unused let's do that. i'll wait :) |
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thank you! |
--- Manual changes: --- 1) Updated version of google_benchmark to fix windows compile error. New range: https://chromium.googlesource.com/external/github.com/google/benchmark/+log/e8baf26..b177433 2) Remove unused sleep.[cc|h] from BUILD.gn. (Removed here: google/benchmark#1549) 3) Fix deprecation warnings (treated as errors) in allocation_perf.cc. benchmark::DoNotOptimize has deprecated overloads due to google/benchmark#1493. Bug: 1425054 --- Original message generated by autoroll: --- Rolling v8/third_party/google_benchmark/src: https://chromium.googlesource.com/external/github.com/google/benchmark/+log/e8baf26..efc89f0 link to benchmark directly for tests that aren't link_main_test (#1576) (dominic) https://chromium.googlesource.com/external/github.com/google/benchmark/+/efc89f0 Convert uses of `const char*` to `std::string` (#1567) (dominic) https://chromium.googlesource.com/external/github.com/google/benchmark/+/46d3c84 add '@' to correctly reference build file for libpfm (#1575) (dominic) https://chromium.googlesource.com/external/github.com/google/benchmark/+/68aa190 Address warnings on NVIDIA nvc++ (#1573) (Henrique Bucher) https://chromium.googlesource.com/external/github.com/google/benchmark/+/9f7dc38 simplify setting C++ standard (Dominic Hamon) https://chromium.googlesource.com/external/github.com/google/benchmark/+/1b507cb [FR] Provide public accessors to benchmark name and arguments #1551 (#1563) (Mike Apodaca) https://chromium.googlesource.com/external/github.com/google/benchmark/+/f32748c use std::string for skip messages (#1571) (dominic) https://chromium.googlesource.com/external/github.com/google/benchmark/+/060d762 [FR] state.SkipWithMessage #963 (#1564) (Mike Apodaca) https://chromium.googlesource.com/external/github.com/google/benchmark/+/adb0d3d ... Change-Id: I69218b84b88fb1da25e740d7fb623528d526b85b Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/4429376 Reviewed-by: Toon Verwaest <[email protected]> Commit-Queue: Matthias Liedtke <[email protected]> Cr-Commit-Position: refs/heads/main@{#87139}
I used to run llvm-test-suite on the riscv64 platform, but I found that the CPU frequency given by the benchmark framework was incorrect. Unfortunately, neither the
cpufreqinterface norBogoMIPSis implemented on the linux-riscv64 platform, it just usesrdcycleandnanosleepto estimate CPU frequency.However, cycle counters are per-core on RISC-V, and what “sleep” means is also not standardized by the RISC-V specifications.
On my machine, calling
nanosleepdoesn't work because the cycle counter doesn't increase during sleeping. Furthermore, it does not prevent thread migration during timing.Please also refer to riscv/riscv-isa-manual#140 and the RISC-V Instruction Set Manual.
I use the pseudo-random number generator given by
<random>instead of callingSleepForMillisecondsas the load and temporarily pin the current thread to a core during timing. This patch works fine on my machine.It has been tested on the following platforms:
If it is OK, I can also drop bogoMIPS and just use the estimation to close #312.
Since
SleepForMillisecondsis no longer used,sleep.handsleep.cccan be removed from the framework.