diff options
| author | Daniel S Fava <danielsfava@gmail.com> | 2020-11-20 21:23:45 +0100 |
|---|---|---|
| committer | Ian Lance Taylor <iant@golang.org> | 2020-11-25 15:59:35 +0000 |
| commit | df68e01b6860e585033156e84f8f9716d2f41a28 (patch) | |
| tree | aa36a6a8e82986473dc1d1473b1db959c6b4b9a8 /src/runtime/select.go | |
| parent | 1d3baf20dcac2d9ad88634ac3fe75e9f6d966971 (diff) | |
| download | go-df68e01b6860e585033156e84f8f9716d2f41a28.tar.gz go-df68e01b6860e585033156e84f8f9716d2f41a28.zip | |
runtime: check channel's elemsize before calling race detector
When c.elemsize==0 we call raceacquire() and racerelease()
as opposed to calling racereleaseacquire()
The reason for this change is that, when elemsize==0, we don't
allocate a full buffer for the channel. Instead of individual
buffer entries, the race detector uses the c.buf as the only
buffer entry. This simplification prevents us following the
memory model's happens-before rules implemented in racereleaseacquire().
So, instead of calling racereleaseacquire(), we accumulate
happens-before information in the synchronization object associated
with c.buf.
The functionality in this change is implemented in a new function
called racenotify()
Fixes #42598
Change-Id: I75b92708633fdfde658dc52e06264e2171824e51
Reviewed-on: https://go-review.googlesource.com/c/go/+/271987
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Ian Lance Taylor <iant@golang.org>
Diffstat (limited to 'src/runtime/select.go')
| -rw-r--r-- | src/runtime/select.go | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/src/runtime/select.go b/src/runtime/select.go index f04b130b15..e72761bfa9 100644 --- a/src/runtime/select.go +++ b/src/runtime/select.go @@ -415,7 +415,7 @@ bufrecv: if cas.elem != nil { raceWriteObjectPC(c.elemtype, cas.elem, casePC(casi), chanrecvpc) } - racereleaseacquire(chanbuf(c, c.recvx)) + racenotify(c, c.recvx, nil) } if msanenabled && cas.elem != nil { msanwrite(cas.elem, c.elemtype.size) @@ -437,7 +437,7 @@ bufrecv: bufsend: // can send to buffer if raceenabled { - racereleaseacquire(chanbuf(c, c.sendx)) + racenotify(c, c.sendx, nil) raceReadObjectPC(c.elemtype, cas.elem, casePC(casi), chansendpc) } if msanenabled { |