github.com/fafucoder/cilium@v1.6.11/pkg/safetime/safetime.go (about)

     1  // Copyright 2018 Authors of Cilium
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package safetime
    16  
    17  import (
    18  	"runtime"
    19  	"time"
    20  
    21  	"github.com/cilium/cilium/pkg/logging/logfields"
    22  
    23  	log "github.com/sirupsen/logrus"
    24  )
    25  
    26  // TimeSinceSafe returns the duration since t. If the duration is negative,
    27  // returns false to indicate the fact.
    28  //
    29  // Used to workaround a malfunctioning monotonic clock.
    30  func TimeSinceSafe(t time.Time, logger *log.Entry) (time.Duration, bool) {
    31  	n := time.Now()
    32  	d := n.Sub(t)
    33  
    34  	if d < 0 {
    35  		logger = logger.WithFields(log.Fields{
    36  			logfields.StartTime: t,
    37  			logfields.EndTime:   n,
    38  			logfields.Duration:  d,
    39  		})
    40  		_, file, line, ok := runtime.Caller(1)
    41  		if ok {
    42  			logger = logger.WithFields(log.Fields{
    43  				logfields.Path: file,
    44  				logfields.Line: line,
    45  			})
    46  		}
    47  		logger.Warn("BUG: negative duration")
    48  
    49  		return time.Duration(0), false
    50  	}
    51  
    52  	return d, true
    53  }