diff options
Diffstat (limited to 'src/runtime/runtime2.go')
| -rw-r--r-- | src/runtime/runtime2.go | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/src/runtime/runtime2.go b/src/runtime/runtime2.go index 5017a7a80a..2a02e1fb3b 100644 --- a/src/runtime/runtime2.go +++ b/src/runtime/runtime2.go @@ -342,7 +342,7 @@ type gobuf struct { bp uintptr // for framepointer-enabled architectures } -// sudog represents a g in a wait list, such as for sending/receiving +// sudog (pseudo-g) represents a g in a wait list, such as for sending/receiving // on a channel. // // sudog is necessary because the g ↔ synchronization object relation @@ -382,6 +382,13 @@ type sudog struct { // because c was closed. success bool + // waiters is a count of semaRoot waiting list other than head of list, + // clamped to a uint16 to fit in unused space. + // Only meaningful at the head of the list. + // (If we wanted to be overly clever, we could store a high 16 bits + // in the second entry in the list.) + waiters uint16 + parent *sudog // semaRoot binary tree waitlink *sudog // g.waiting list or semaRoot waittail *sudog // semaRoot |