diff options
Diffstat (limited to 'pkg/sentry/kernel')
-rw-r--r-- | pkg/sentry/kernel/seqatomic_taskgoroutineschedinfo_unsafe.go | 36 |
1 files changed, 15 insertions, 21 deletions
diff --git a/pkg/sentry/kernel/seqatomic_taskgoroutineschedinfo_unsafe.go b/pkg/sentry/kernel/seqatomic_taskgoroutineschedinfo_unsafe.go index 950645965..90148bbb2 100644 --- a/pkg/sentry/kernel/seqatomic_taskgoroutineschedinfo_unsafe.go +++ b/pkg/sentry/kernel/seqatomic_taskgoroutineschedinfo_unsafe.go @@ -10,39 +10,33 @@ import ( ) // SeqAtomicLoad returns a copy of *ptr, ensuring that the read does not race -// with any writer critical sections in sc. -func SeqAtomicLoadTaskGoroutineSchedInfo(sc *sync.SeqCount, ptr *TaskGoroutineSchedInfo) TaskGoroutineSchedInfo { - // This function doesn't use SeqAtomicTryLoad because doing so is - // measurably, significantly (~20%) slower; Go is awful at inlining. - var val TaskGoroutineSchedInfo +// with any writer critical sections in seq. +// +//go:nosplit +func SeqAtomicLoadTaskGoroutineSchedInfo(seq *sync.SeqCount, ptr *TaskGoroutineSchedInfo) TaskGoroutineSchedInfo { for { - epoch := sc.BeginRead() - if sync.RaceEnabled { - - sync.Memmove(unsafe.Pointer(&val), unsafe.Pointer(ptr), unsafe.Sizeof(val)) - } else { - - val = *ptr - } - if sc.ReadOk(epoch) { - break + if val, ok := SeqAtomicTryLoadTaskGoroutineSchedInfo(seq, seq.BeginRead(), ptr); ok { + return val } } - return val } // SeqAtomicTryLoad returns a copy of *ptr while in a reader critical section -// in sc initiated by a call to sc.BeginRead() that returned epoch. If the read -// would race with a writer critical section, SeqAtomicTryLoad returns +// in seq initiated by a call to seq.BeginRead() that returned epoch. If the +// read would race with a writer critical section, SeqAtomicTryLoad returns // (unspecified, false). -func SeqAtomicTryLoadTaskGoroutineSchedInfo(sc *sync.SeqCount, epoch sync.SeqCountEpoch, ptr *TaskGoroutineSchedInfo) (TaskGoroutineSchedInfo, bool) { - var val TaskGoroutineSchedInfo +// +//go:nosplit +func SeqAtomicTryLoadTaskGoroutineSchedInfo(seq *sync.SeqCount, epoch sync.SeqCountEpoch, ptr *TaskGoroutineSchedInfo) (val TaskGoroutineSchedInfo, ok bool) { if sync.RaceEnabled { + sync.Memmove(unsafe.Pointer(&val), unsafe.Pointer(ptr), unsafe.Sizeof(val)) } else { + val = *ptr } - return val, sc.ReadOk(epoch) + ok = seq.ReadOk(epoch) + return } func initTaskGoroutineSchedInfo() { |