diff options
| -rw-r--r-- | cmd/ioworkload/scenario_polling.go | 31 | ||||
| -rw-r--r-- | cmd/ioworkload/scenario_polling_test.go | 33 | ||||
| -rw-r--r-- | integrationtests/polling_test.go | 58 |
3 files changed, 103 insertions, 19 deletions
diff --git a/cmd/ioworkload/scenario_polling.go b/cmd/ioworkload/scenario_polling.go index 6a97f57..1531511 100644 --- a/cmd/ioworkload/scenario_polling.go +++ b/cmd/ioworkload/scenario_polling.go @@ -1,6 +1,7 @@ package main import ( + "errors" "fmt" "runtime" "syscall" @@ -29,6 +30,7 @@ func pollingEpoll() error { return fmt.Errorf("epoll_ctl add: %w", err) } + pwait2Supported := true deadline := time.Now().Add(5 * time.Second) for time.Now().Before(deadline) { if err := waitAndDrain(epfd, pipefd, callEpollWait); err != nil { @@ -37,8 +39,16 @@ func pollingEpoll() error { if err := waitAndDrain(epfd, pipefd, callEpollPwait); err != nil { return err } - if err := waitAndDrain(epfd, pipefd, callEpollPwait2); err != nil { - return err + if pwait2Supported { + if err := waitAndDrain(epfd, pipefd, callEpollPwait2); err != nil { + if !isUnsupportedEpollPwait2Err(err) { + return err + } + if drainErr := drainWakeByte(pipefd[0]); drainErr != nil { + return drainErr + } + pwait2Supported = false + } } } @@ -57,8 +67,12 @@ func waitAndDrain(epfd int, pipefd [2]int, waitFn func(int, []unix.EpollEvent) ( if ready < 1 { return fmt.Errorf("epoll wait returned %d ready events", ready) } + return drainWakeByte(pipefd[0]) +} + +func drainWakeByte(readFD int) error { var buf [1]byte - if _, err := syscall.Read(pipefd[0], buf[:]); err != nil { + if _, err := syscall.Read(readFD, buf[:]); err != nil { return fmt.Errorf("drain wake byte: %w", err) } return nil @@ -119,3 +133,14 @@ func callEpollPwait2(epfd int, events []unix.EpollEvent) (int, error) { } return int(r1), nil } + +func isUnsupportedEpollPwait2Err(err error) bool { + if err == nil { + return false + } + var errno syscall.Errno + if !errors.As(err, &errno) { + return false + } + return errno == syscall.ENOSYS || errno == syscall.ENOTSUP +} diff --git a/cmd/ioworkload/scenario_polling_test.go b/cmd/ioworkload/scenario_polling_test.go new file mode 100644 index 0000000..83e6d7c --- /dev/null +++ b/cmd/ioworkload/scenario_polling_test.go @@ -0,0 +1,33 @@ +package main + +import ( + "fmt" + "syscall" + "testing" +) + +func TestIsUnsupportedEpollPwait2Err(t *testing.T) { + t.Parallel() + + tests := []struct { + name string + err error + want bool + }{ + {name: "nil", err: nil, want: false}, + {name: "enosys", err: fmt.Errorf("epoll_pwait2: %w", syscall.ENOSYS), want: true}, + {name: "enotsup", err: fmt.Errorf("epoll_pwait2: %w", syscall.ENOTSUP), want: true}, + {name: "einval", err: fmt.Errorf("epoll_pwait2: %w", syscall.EINVAL), want: false}, + {name: "opaque", err: fmt.Errorf("epoll_pwait2: not-supported"), want: false}, + } + + for _, tt := range tests { + t.Run(tt.name, func(t *testing.T) { + t.Parallel() + got := isUnsupportedEpollPwait2Err(tt.err) + if got != tt.want { + t.Fatalf("isUnsupportedEpollPwait2Err(%v) = %v, want %v", tt.err, got, tt.want) + } + }) + } +} diff --git a/integrationtests/polling_test.go b/integrationtests/polling_test.go index af3806a..cea535e 100644 --- a/integrationtests/polling_test.go +++ b/integrationtests/polling_test.go @@ -1,6 +1,9 @@ package integrationtests -import "testing" +import ( + "strings" + "testing" +) const ( pollingParquetDuration = 10 @@ -21,8 +24,11 @@ func TestPollingEpollTracepoints(t *testing.T) { {Tracepoint: "enter_epoll_ctl", Comm: "ioworkload", MinCount: 1}, {Tracepoint: "enter_epoll_wait", Comm: "ioworkload", MinCount: 1}, {Tracepoint: "enter_epoll_pwait", Comm: "ioworkload", MinCount: 1}, - {Tracepoint: "enter_epoll_pwait2", Comm: "ioworkload", MinCount: 1}, }) + + if !hasTracepoint(result, "enter_epoll_pwait2") { + t.Log("enter_epoll_pwait2 not observed; treating as unsupported-kernel path") + } } func TestPollingEpollReadyCountInParquet(t *testing.T) { @@ -38,21 +44,26 @@ func TestPollingEpollReadyCountInParquet(t *testing.T) { t.Fatalf("expected parquet rows for workload PID %d", pid) } - wantReadyCount := map[string]bool{ - "epoll_wait": false, - "epoll_pwait": false, - "epoll_pwait2": false, - } + wantReadyCount := map[string]bool{"epoll_wait": false, "epoll_pwait": false} + var sawPwait2 bool + var sawPwait2ReadyCount bool for _, row := range rows { - _, tracked := wantReadyCount[row.Syscall] - if !tracked { - continue - } - if row.Ret > 0 { - wantReadyCount[row.Syscall] = true - } - if row.Bytes != 0 { - t.Fatalf("%s bytes = %d, want 0 for ready-count events", row.Syscall, row.Bytes) + switch row.Syscall { + case "epoll_wait", "epoll_pwait": + if row.Ret > 0 { + wantReadyCount[row.Syscall] = true + } + if row.Bytes != 0 { + t.Fatalf("%s bytes = %d, want 0 for ready-count events", row.Syscall, row.Bytes) + } + case "epoll_pwait2": + sawPwait2 = true + if row.Ret > 0 { + sawPwait2ReadyCount = true + } + if row.Bytes != 0 { + t.Fatalf("%s bytes = %d, want 0 for ready-count events", row.Syscall, row.Bytes) + } } } @@ -61,4 +72,19 @@ func TestPollingEpollReadyCountInParquet(t *testing.T) { t.Fatalf("expected %s row with positive ready-count ret in parquet output", syscall) } } + if sawPwait2 && !sawPwait2ReadyCount { + t.Fatalf("expected epoll_pwait2 row with positive ready-count ret when epoll_pwait2 is present") + } + if !sawPwait2 { + t.Log("epoll_pwait2 parquet rows not observed; treating as unsupported-kernel path") + } +} + +func hasTracepoint(result TestResult, tracepoint string) bool { + for _, rec := range result.Records { + if strings.Contains(rec.TraceID.String(), tracepoint) { + return true + } + } + return false } |