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Diffstat (limited to 'pkg/sentry/vfs/epoll.go')
-rw-r--r--pkg/sentry/vfs/epoll.go27
1 files changed, 15 insertions, 12 deletions
diff --git a/pkg/sentry/vfs/epoll.go b/pkg/sentry/vfs/epoll.go
index 1b5af9f73..a98aac52b 100644
--- a/pkg/sentry/vfs/epoll.go
+++ b/pkg/sentry/vfs/epoll.go
@@ -27,6 +27,8 @@ import (
var epollCycleMu sync.Mutex
// EpollInstance represents an epoll instance, as described by epoll(7).
+//
+// +stateify savable
type EpollInstance struct {
vfsfd FileDescription
FileDescriptionDefaultImpl
@@ -38,11 +40,11 @@ type EpollInstance struct {
// interest is the set of file descriptors that are registered with the
// EpollInstance for monitoring. interest is protected by interestMu.
- interestMu sync.Mutex
+ interestMu sync.Mutex `state:"nosave"`
interest map[epollInterestKey]*epollInterest
// mu protects fields in registered epollInterests.
- mu sync.Mutex
+ mu sync.Mutex `state:"nosave"`
// ready is the set of file descriptors that may be "ready" for I/O. Note
// that this must be an ordered list, not a map: "If more than maxevents
@@ -55,6 +57,7 @@ type EpollInstance struct {
ready epollInterestList
}
+// +stateify savable
type epollInterestKey struct {
// file is the registered FileDescription. No reference is held on file;
// instead, when the last reference is dropped, FileDescription.DecRef()
@@ -67,9 +70,11 @@ type epollInterestKey struct {
}
// epollInterest represents an EpollInstance's interest in a file descriptor.
+//
+// +stateify savable
type epollInterest struct {
// epoll is the owning EpollInstance. epoll is immutable.
- epoll *EpollInstance
+ epoll *EpollInstance `state:"wait"`
// key is the file to which this epollInterest applies. key is immutable.
key epollInterestKey
@@ -331,11 +336,9 @@ func (ep *EpollInstance) removeLocked(epi *epollInterest) {
ep.mu.Unlock()
}
-// ReadEvents reads up to len(events) ready events into events and returns the
-// number of events read.
-//
-// Preconditions: len(events) != 0.
-func (ep *EpollInstance) ReadEvents(events []linux.EpollEvent) int {
+// ReadEvents appends up to maxReady events to events and returns the updated
+// slice of events.
+func (ep *EpollInstance) ReadEvents(events []linux.EpollEvent, maxEvents int) []linux.EpollEvent {
i := 0
// Hot path: avoid defer.
ep.mu.Lock()
@@ -368,16 +371,16 @@ func (ep *EpollInstance) ReadEvents(events []linux.EpollEvent) int {
requeue.PushBack(epi)
}
// Report ievents.
- events[i] = linux.EpollEvent{
+ events = append(events, linux.EpollEvent{
Events: ievents.ToLinux(),
Data: epi.userData,
- }
+ })
i++
- if i == len(events) {
+ if i == maxEvents {
break
}
}
ep.ready.PushBackList(&requeue)
ep.mu.Unlock()
- return i
+ return events
}