diff options
| -rw-r--r-- | libpod/lock/lock.go | 11 | ||||
| -rw-r--r-- | libpod/lock/shm/shm_lock.go | 8 | ||||
| -rw-r--r-- | libpod/lock/shm_lock_manager_linux.go | 12 | ||||
| -rw-r--r-- | libpod/runtime.go | 110 |
4 files changed, 95 insertions, 46 deletions
diff --git a/libpod/lock/lock.go b/libpod/lock/lock.go index 5258c641f..73c1fdcf7 100644 --- a/libpod/lock/lock.go +++ b/libpod/lock/lock.go @@ -41,11 +41,14 @@ type Locker interface { // Lock locks the lock. // This call MUST block until it successfully acquires the lock or // encounters a fatal error. - Lock() error + // All errors must be handled internally, as they are not returned. For + // the most part, panicking should be appropriate. + Lock() // Unlock unlocks the lock. - // A call to Unlock() on a lock that is already unlocked lock MUST - // error. - Unlock() error + // All errors must be handled internally, as they are not returned. For + // the most part, panicking should be appropriate. + // This includes unlocking locks which are already unlocked. + Unlock() // Free deallocates the underlying lock, allowing its reuse by other // pods and containers. // The lock MUST still be usable after a Free() - some libpod instances diff --git a/libpod/lock/shm/shm_lock.go b/libpod/lock/shm/shm_lock.go index 16d7f2008..3372a8c71 100644 --- a/libpod/lock/shm/shm_lock.go +++ b/libpod/lock/shm/shm_lock.go @@ -12,9 +12,13 @@ import ( "unsafe" "github.com/pkg/errors" + "github.com/sirupsen/logrus" ) -const ( +var ( + // BitmapSize is the size of the bitmap used when managing SHM locks. + // an SHM lock manager's max locks will be rounded up to a multiple of + // this number. BitmapSize uint32 = uint32(C.bitmap_size_c) ) @@ -51,6 +55,8 @@ func CreateSHMLock(path string, numLocks uint32) (*SHMLocks, error) { locks.maxLocks = uint32(lockStruct.num_locks) locks.valid = true + logrus.Debugf("Initialized SHM lock manager at path %s", path) + return locks, nil } diff --git a/libpod/lock/shm_lock_manager_linux.go b/libpod/lock/shm_lock_manager_linux.go index 974431a13..2c0ea611a 100644 --- a/libpod/lock/shm_lock_manager_linux.go +++ b/libpod/lock/shm_lock_manager_linux.go @@ -73,13 +73,17 @@ func (l *SHMLock) ID() uint32 { } // Lock acquires the lock. -func (l *SHMLock) Lock() error { - return l.manager.locks.LockSemaphore(l.lockID) +func (l *SHMLock) Lock() { + if err := l.manager.locks.LockSemaphore(l.lockID); err != nil { + panic(err.Error()) + } } // Unlock releases the lock. -func (l *SHMLock) Unlock() error { - return l.manager.locks.UnlockSemaphore(l.lockID) +func (l *SHMLock) Unlock() { + if err := l.manager.locks.UnlockSemaphore(l.lockID); err != nil { + panic(err.Error()) + } } // Free releases the lock, allowing it to be reused. diff --git a/libpod/runtime.go b/libpod/runtime.go index facbe5d66..238a7a9db 100644 --- a/libpod/runtime.go +++ b/libpod/runtime.go @@ -11,6 +11,7 @@ import ( is "github.com/containers/image/storage" "github.com/containers/image/types" "github.com/containers/libpod/libpod/image" + "github.com/containers/libpod/libpod/lock" "github.com/containers/libpod/pkg/firewall" sysreg "github.com/containers/libpod/pkg/registries" "github.com/containers/libpod/pkg/rootless" @@ -64,6 +65,11 @@ const ( // DefaultInitPath is the default path to the container-init binary DefaultInitPath = "/usr/libexec/podman/catatonit" + + // DefaultSHMLockPath is the default path for SHM locks + DefaultSHMLockPath = "/libpod_lock" + // DefaultRootlessSHMLockPath is the default path for rootless SHM locks + DefaultRootlessSHMLockPath = "/libpod_rootless_lock" ) // A RuntimeOption is a functional option which alters the Runtime created by @@ -86,6 +92,7 @@ type Runtime struct { lock sync.RWMutex imageRuntime *image.Runtime firewallBackend firewall.FirewallBackend + lockManager lock.Manager configuredFrom *runtimeConfiguredFrom } @@ -165,6 +172,7 @@ type RuntimeConfig struct { // and all containers and pods will be visible. // The default namespace is "". Namespace string `toml:"namespace,omitempty"` + // InfraImage is the image a pod infra container will use to manage namespaces InfraImage string `toml:"infra_image"` // InfraCommand is the command run to start up a pod infra container @@ -179,6 +187,10 @@ type RuntimeConfig struct { EnablePortReservation bool `toml:"enable_port_reservation"` // EnableLabeling indicates wether libpod will support container labeling EnableLabeling bool `toml:"label"` + + // NumLocks is the number of locks to make available for containers and + // pods. + NumLocks uint32 `toml:"num_locks,omitempty"` } // runtimeConfiguredFrom is a struct used during early runtime init to help @@ -234,6 +246,7 @@ var ( InfraImage: DefaultInfraImage, EnablePortReservation: true, EnableLabeling: true, + NumLocks: 2048, } ) @@ -487,6 +500,56 @@ func makeRuntime(runtime *Runtime) (err error) { } } + // We now need to see if the system has restarted + // We check for the presence of a file in our tmp directory to verify this + // This check must be locked to prevent races + runtimeAliveLock := filepath.Join(runtime.config.TmpDir, "alive.lck") + runtimeAliveFile := filepath.Join(runtime.config.TmpDir, "alive") + aliveLock, err := storage.GetLockfile(runtimeAliveLock) + if err != nil { + return errors.Wrapf(err, "error acquiring runtime init lock") + } + // Acquire the lock and hold it until we return + // This ensures that no two processes will be in runtime.refresh at once + // TODO: we can't close the FD in this lock, so we should keep it around + // and use it to lock important operations + aliveLock.Lock() + locked := true + doRefresh := false + defer func() { + if locked { + aliveLock.Unlock() + } + }() + _, err = os.Stat(runtimeAliveFile) + if err != nil { + // If the file doesn't exist, we need to refresh the state + // This will trigger on first use as well, but refreshing an + // empty state only creates a single file + // As such, it's not really a performance concern + if os.IsNotExist(err) { + doRefresh = true + } else { + return errors.Wrapf(err, "error reading runtime status file %s", runtimeAliveFile) + } + } + + // Set up the lock manager + var manager lock.Manager + lockPath := DefaultSHMLockPath + if rootless.IsRootless() { + lockPath = DefaultRootlessSHMLockPath + } + if doRefresh { + manager, err = lock.NewSHMLockManager(lockPath, runtime.config.NumLocks) + } else { + manager, err = lock.OpenSHMLockManager(lockPath, runtime.config.NumLocks) + } + if err != nil { + return errors.Wrapf(err, "error initializing SHM locking") + } + runtime.lockManager = manager + // Set up the state switch runtime.config.StateType { case InMemoryStateStore: @@ -656,46 +719,19 @@ func makeRuntime(runtime *Runtime) (err error) { } runtime.firewallBackend = fwBackend - // We now need to see if the system has restarted - // We check for the presence of a file in our tmp directory to verify this - // This check must be locked to prevent races - runtimeAliveLock := filepath.Join(runtime.config.TmpDir, "alive.lck") - runtimeAliveFile := filepath.Join(runtime.config.TmpDir, "alive") - aliveLock, err := storage.GetLockfile(runtimeAliveLock) - if err != nil { - return errors.Wrapf(err, "error acquiring runtime init lock") - } - // Acquire the lock and hold it until we return - // This ensures that no two processes will be in runtime.refresh at once - // TODO: we can't close the FD in this lock, so we should keep it around - // and use it to lock important operations - aliveLock.Lock() - locked := true - defer func() { - if locked { + // If we need to refresh the state, do it now - things are guaranteed to + // be set up by now. + if doRefresh { + if os.Geteuid() != 0 { aliveLock.Unlock() - } - }() - _, err = os.Stat(runtimeAliveFile) - if err != nil { - // If the file doesn't exist, we need to refresh the state - // This will trigger on first use as well, but refreshing an - // empty state only creates a single file - // As such, it's not really a performance concern - if os.IsNotExist(err) { - if os.Geteuid() != 0 { - aliveLock.Unlock() - locked = false - if err2 := runtime.refreshRootless(); err2 != nil { - return err2 - } - } else { - if err2 := runtime.refresh(runtimeAliveFile); err2 != nil { - return err2 - } + locked = false + if err2 := runtime.refreshRootless(); err2 != nil { + return err2 } } else { - return errors.Wrapf(err, "error reading runtime status file %s", runtimeAliveFile) + if err2 := runtime.refresh(runtimeAliveFile); err2 != nil { + return err2 + } } } |