gvisor.dev/gvisor@v0.0.0-20240520182842-f9d4d51c7e0f/pkg/sentry/state/state_unsafe.go (about)

     1  // Copyright 2018 The gVisor Authors.
     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 state
    16  
    17  import (
    18  	"fmt"
    19  	"time"
    20  	"unsafe"
    21  
    22  	"golang.org/x/sys/unix"
    23  	"gvisor.dev/gvisor/pkg/abi/linux"
    24  )
    25  
    26  // CPUTime returns the CPU time usage by Sentry and app.
    27  func CPUTime() (time.Duration, error) {
    28  	var ts unix.Timespec
    29  	_, _, errno := unix.RawSyscall(unix.SYS_CLOCK_GETTIME, uintptr(linux.CLOCK_PROCESS_CPUTIME_ID), uintptr(unsafe.Pointer(&ts)), 0)
    30  	if errno != 0 {
    31  		return 0, fmt.Errorf("failed calling clock_gettime(CLOCK_PROCESS_CPUTIME_ID): errno=%d", errno)
    32  	}
    33  	return time.Duration(ts.Nano()), nil
    34  }