github.com/metacubex/gvisor@v0.0.0-20240320004321-933faba989ec/runsc/boot/autosave.go (about)

     1  // Copyright 2024 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 boot
    16  
    17  import (
    18  	"fmt"
    19  	"os"
    20  
    21  	"github.com/metacubex/gvisor/pkg/abi/linux"
    22  	"github.com/metacubex/gvisor/pkg/log"
    23  	"github.com/metacubex/gvisor/pkg/sentry/arch"
    24  	"github.com/metacubex/gvisor/pkg/sentry/kernel"
    25  	"github.com/metacubex/gvisor/pkg/sentry/state"
    26  	"github.com/metacubex/gvisor/pkg/sentry/strace"
    27  	"github.com/metacubex/gvisor/pkg/sync"
    28  )
    29  
    30  // EnableAutosave enables auto save restore in syscall tests.
    31  func EnableAutosave(l *Loader, f *os.File) error {
    32  	var once sync.Once // Used by target.
    33  	target := func(k *kernel.Kernel) {
    34  		once.Do(func() {
    35  			t, _ := state.CPUTime()
    36  			log.Infof("Before save CPU usage: %s", t.String())
    37  			saveOpts := state.SaveOpts{
    38  				Destination: f,
    39  				Key:         nil,
    40  				Callback: func(err error) {
    41  					t1, _ := state.CPUTime()
    42  					log.Infof("Save CPU usage: %s", (t1 - t).String())
    43  					if err == nil {
    44  						log.Infof("Save succeeded: exiting...")
    45  						k.SetSaveSuccess(true)
    46  					} else {
    47  						log.Warningf("Save failed: exiting... %v", err)
    48  						k.SetSaveError(err)
    49  					}
    50  
    51  					// Kill the sandbox.
    52  					k.Kill(linux.WaitStatusExit(0))
    53  				},
    54  			}
    55  			saveOpts.Save(k.SupervisorContext(), k, l.watchdog)
    56  		})
    57  	}
    58  
    59  	for _, table := range kernel.SyscallTables() {
    60  		sys, ok := strace.Lookup(table.OS, table.Arch)
    61  		if !ok {
    62  			continue
    63  		}
    64  		if err := configureInitSyscall(table, sys, "init_module", kernel.ExternalAfterEnable); err != nil {
    65  			return err
    66  		}
    67  		// Set external args to our closure above.
    68  		table.External = target
    69  	}
    70  
    71  	return nil
    72  }
    73  
    74  // configureInitSyscall sets the trigger for the S/R syscall tests and the callback
    75  // method to be called after the sycall is executed.
    76  func configureInitSyscall(table *kernel.SyscallTable, sys strace.SyscallMap, initSyscall string, syscallFlag uint32) error {
    77  	sl := make(map[uintptr]bool)
    78  	sysno, ok := sys.ConvertToSysno(initSyscall)
    79  	if !ok {
    80  		return fmt.Errorf("syscall %q not found", initSyscall)
    81  	}
    82  	sl[sysno] = true
    83  	log.Infof("sysno %v name %v", sysno, initSyscall)
    84  	table.FeatureEnable.Enable(syscallFlag, sl, false)
    85  	table.ExternalFilterBefore = func(*kernel.Task, uintptr, arch.SyscallArguments) bool {
    86  		return false
    87  	}
    88  	// Sets ExternalFilterAfter to true which calls the closure assigned to
    89  	// External after the syscall is executed.
    90  	table.ExternalFilterAfter = func(*kernel.Task, uintptr, arch.SyscallArguments) bool {
    91  		return true
    92  	}
    93  	return nil
    94  }