Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

release-23.2: rangefeed: fix scheduler catchup iterator race #114379

Merged
merged 1 commit into from
Nov 15, 2023
Merged

release-23.2: rangefeed: fix scheduler catchup iterator race #114379

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
25 changes: 23 additions & 2 deletions pkg/kv/kvserver/rangefeed/scheduled_processor.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -18,6 +18,7 @@ import (
"github.com/cockroachdb/cockroach/pkg/kv/kvpb"
"github.com/cockroachdb/cockroach/pkg/roachpb"
"github.com/cockroachdb/cockroach/pkg/storage/enginepb"
"github.com/cockroachdb/cockroach/pkg/util/buildutil"
"github.com/cockroachdb/cockroach/pkg/util/future"
"github.com/cockroachdb/cockroach/pkg/util/hlc"
"github.com/cockroachdb/cockroach/pkg/util/log"
Expand Down Expand Up @@ -574,19 +575,39 @@ func (p *ScheduledProcessor) Filter() *Filter {
// is guaranteed that only single request is modifying processor at any given
// time. It is advisable to use provided processor reference for operations
// rather than using one within closure itself.
// If request can't be queued or processor stoppedC is closed then default
// value is returned.
//
// If the processor is stopped concurrently with the request queueing, it may or
// may not be processed. If the request is ever processed, its return value is
// guaranteed to be returned here. Otherwise, the zero value is returned and the
// request is never processed.
func runRequest[T interface{}](
p *ScheduledProcessor, f func(ctx context.Context, p *ScheduledProcessor) T,
) (r T) {
result := make(chan T, 1)
p.enqueueRequest(func(ctx context.Context) {
result <- f(ctx, p)
// Assert that we never process requests after stoppedC is closed. This is
// necessary to coordinate catchup iter ownership and avoid double-closing.
// Note that request/stop processing is always sequential, see process().
if buildutil.CrdbTestBuild {
select {
case <-p.stoppedC:
log.Fatalf(ctx, "processing request on stopped processor")
default:
}
}
})
select {
case r = <-result:
return r
case <-p.stoppedC:
// If a request and stop were processed in rapid succession, and the node is
// overloaded, this select may observe them happening at the same time and
// take this branch instead of the result with 50% probability. Check again.
select {
case r = <-result:
default:
}
return r
}
}
Expand Down