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Guard DBImpl::versions_ by mutex_.

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mutex_ was already acquired before accessing DBImpl::versions_ in all
but one place: DBImpl::GetApproximateSizes. This change requires mutex_
to be held before accessing versions_.

PiperOrigin-RevId: 248390814
This commit is contained in:
Chris Mumford 2019-05-15 13:13:13 -07:00
parent 1d0b101165
commit c00e177f36
2 changed files with 7 additions and 12 deletions
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17
db/db_impl.cc
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@ -893,10 +893,11 @@ Status DBImpl::DoCompactionWork(CompactionState* compact) {
compact->smallest_snapshot = snapshots_.oldest()->sequence_number();
}
Iterator* input = versions_->MakeInputIterator(compact->compaction);
// Release mutex while we're actually doing the compaction work
mutex_.Unlock();
Iterator* input = versions_->MakeInputIterator(compact->compaction);
input->SeekToFirst();
Status status;
ParsedInternalKey ikey;
@ -1433,12 +1434,9 @@ bool DBImpl::GetProperty(const Slice& property, std::string* value) {
void DBImpl::GetApproximateSizes(const Range* range, int n, uint64_t* sizes) {
// TODO(opt): better implementation
Version* v;
{
MutexLock l(&mutex_);
versions_->current()->Ref();
v = versions_->current();
}
MutexLock l(&mutex_);
Version* v = versions_->current();
v->Ref();
for (int i = 0; i < n; i++) {
// Convert user_key into a corresponding internal key.
@ -1449,10 +1447,7 @@ void DBImpl::GetApproximateSizes(const Range* range, int n, uint64_t* sizes) {
sizes[i] = (limit >= start ? limit - start : 0);
}
{
MutexLock l(&mutex_);
v->Unref();
}
v->Unref();
}
// Default implementations of convenience methods that subclasses of DB

2
db/db_impl.h
View File

@ -197,7 +197,7 @@ class DBImpl : public DB {
ManualCompaction* manual_compaction_ GUARDED_BY(mutex_);
VersionSet* const versions_;
VersionSet* const versions_ GUARDED_BY(mutex_);
// Have we encountered a background error in paranoid mode?
Status bg_error_ GUARDED_BY(mutex_);