github.com/ice-blockchain/go/src@v0.0.0-20240403114104-1564d284e521/internal/trace/v2/testdata/generators/go122-syscall-steal-proc-ambiguous.go (about) 1 // Copyright 2023 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 // Tests syscall P stealing. 6 // 7 // Specifically, it tests a scenerio wherein, without a 8 // P sequence number of GoSyscallBegin, the syscall that 9 // a ProcSteal applies to is ambiguous. This only happens in 10 // practice when the events aren't already properly ordered 11 // by timestamp, since the ProcSteal won't be seen until after 12 // the correct GoSyscallBegin appears on the frontier. 13 14 package main 15 16 import ( 17 "internal/trace/v2" 18 "internal/trace/v2/event/go122" 19 testgen "internal/trace/v2/internal/testgen/go122" 20 ) 21 22 func main() { 23 testgen.Main(gen) 24 } 25 26 func gen(t *testgen.Trace) { 27 t.DisableTimestamps() 28 29 g := t.Generation(1) 30 31 // One goroutine does a syscall without blocking, then another one where 32 // it's P gets stolen. 33 b0 := g.Batch(trace.ThreadID(0), 0) 34 b0.Event("ProcStatus", trace.ProcID(0), go122.ProcRunning) 35 b0.Event("GoStatus", trace.GoID(1), trace.ThreadID(0), go122.GoRunning) 36 b0.Event("GoSyscallBegin", testgen.Seq(1), testgen.NoStack) 37 b0.Event("GoSyscallEnd") 38 b0.Event("GoSyscallBegin", testgen.Seq(2), testgen.NoStack) 39 b0.Event("GoSyscallEndBlocked") 40 41 // A running goroutine steals proc 0. 42 b1 := g.Batch(trace.ThreadID(1), 0) 43 b1.Event("ProcStatus", trace.ProcID(2), go122.ProcRunning) 44 b1.Event("GoStatus", trace.GoID(2), trace.ThreadID(1), go122.GoRunning) 45 b1.Event("ProcSteal", trace.ProcID(0), testgen.Seq(3), trace.ThreadID(0)) 46 }