program: block SIGPROF during BPF_PROG_RUN #887
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lmb
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Extend the profiler blocking we introduced for BPF_PROG_LOAD to BPF_PROG_RUN, with the difference that EINTR is not handled in the syscall wrapper itself. This allows us to have PROG_RUN specific retry logic. Deprecate RunOptions.Reset since its main motivation was to account for profiler skew. Interruptions from the runtime are only possible via runtime.AllThreadSyscall, which is very specialised anyways. This doesn't protect from interruptions due to signals that are being sent from "outside" the process, which will still skew results and cause retries. Document that RunOptions.Repeat is a lower bound for how often a program is run due to the retry behaviour. Also add a workaround that makes the common case of repeat == 1 not suffer from interruptions. Fixes cilium#853
The BPF command is now called BPF_PROG_RUN, rename testRun to reflect this.
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Extend the profiler blocking we introduced for BPF_PROG_LOAD to BPF_PROG_RUN, with the difference that EINTR is not handled in the syscall wrapper itself. This allows us to have PROG_RUN specific retry logic.
Deprecate RunOptions.Reset since its main motivation was to account for profiler skew. Interruptions from the runtime are only possible via runtime.AllThreadSyscall, which is very specialised anyways. This doesn't protect from interruptions due to signals that are being sent from "outside" the process, which will still skew results and cause retries.
Document that RunOptions.Repeat is a lower bound for how often a program is run due to the retry behaviour. Also add a workaround that makes the common case of repeat == 1 not suffer from interruptions.
Fixes #853