diff options
Diffstat (limited to 'cmd')
| -rw-r--r-- | cmd/ioworkload/scenario_sleep.go | 34 |
1 files changed, 32 insertions, 2 deletions
diff --git a/cmd/ioworkload/scenario_sleep.go b/cmd/ioworkload/scenario_sleep.go index bb6c5a4..c004c4b 100644 --- a/cmd/ioworkload/scenario_sleep.go +++ b/cmd/ioworkload/scenario_sleep.go @@ -21,17 +21,47 @@ func sleepSyscalls() error { if err := callClockNanosleep(3_000_000); err != nil { return err } + // Also exercise the TIMER_ABSTIME (absolute) path so the tracer's + // absolute-sleep handling is covered: the request timespec here is an + // absolute CLOCK_MONOTONIC wakeup time, not a relative duration, so the + // tracer must NOT report it as a sleep duration (see task a20). + if err := callClockNanosleepAbs(2_000_000); err != nil { + return err + } } return nil } +// callClockNanosleep issues a relative clock_nanosleep (flags = 0), sleeping for +// requestedNs nanoseconds. func callClockNanosleep(requestedNs int64) error { req := unix.Timespec{Sec: requestedNs / 1_000_000_000, Nsec: requestedNs % 1_000_000_000} + return invokeClockNanosleep(0, &req) +} + +// callClockNanosleepAbs issues an absolute clock_nanosleep (flags = +// TIMER_ABSTIME). The request timespec is an absolute CLOCK_MONOTONIC wakeup +// time computed as "now + aheadNs", so the call blocks for roughly aheadNs but +// the request value itself is a multi-decade absolute timestamp, not a +// duration. +func callClockNanosleepAbs(aheadNs int64) error { + var now unix.Timespec + if err := unix.ClockGettime(unix.CLOCK_MONOTONIC, &now); err != nil { + return fmt.Errorf("clock_gettime: %w", err) + } + target := now.Nano() + aheadNs + req := unix.Timespec{Sec: target / 1_000_000_000, Nsec: target % 1_000_000_000} + return invokeClockNanosleep(unix.TIMER_ABSTIME, &req) +} + +// invokeClockNanosleep is the shared raw clock_nanosleep syscall wrapper used by +// both the relative and absolute callers. +func invokeClockNanosleep(flags uintptr, req *unix.Timespec) error { _, _, errno := syscall.RawSyscall6( unix.SYS_CLOCK_NANOSLEEP, uintptr(unix.CLOCK_MONOTONIC), - 0, - uintptr(unsafe.Pointer(&req)), + flags, + uintptr(unsafe.Pointer(req)), 0, 0, 0, |