sanitizer_deadlock_detector1.cc [plain text]
#include "sanitizer_deadlock_detector_interface.h"
#include "sanitizer_deadlock_detector.h"
#include "sanitizer_allocator_internal.h"
#include "sanitizer_placement_new.h"
#include "sanitizer_mutex.h"
#if SANITIZER_DEADLOCK_DETECTOR_VERSION == 1
namespace __sanitizer {
typedef TwoLevelBitVector<> DDBV;
struct DDPhysicalThread {
};
struct DDLogicalThread {
u64 ctx;
DeadlockDetectorTLS<DDBV> dd;
DDReport rep;
bool report_pending;
};
struct DD : public DDetector {
SpinMutex mtx;
DeadlockDetector<DDBV> dd;
DDFlags flags;
explicit DD(const DDFlags *flags);
DDPhysicalThread* CreatePhysicalThread();
void DestroyPhysicalThread(DDPhysicalThread *pt);
DDLogicalThread* CreateLogicalThread(u64 ctx);
void DestroyLogicalThread(DDLogicalThread *lt);
void MutexInit(DDCallback *cb, DDMutex *m);
void MutexBeforeLock(DDCallback *cb, DDMutex *m, bool wlock);
void MutexAfterLock(DDCallback *cb, DDMutex *m, bool wlock, bool trylock);
void MutexBeforeUnlock(DDCallback *cb, DDMutex *m, bool wlock);
void MutexDestroy(DDCallback *cb, DDMutex *m);
DDReport *GetReport(DDCallback *cb);
void MutexEnsureID(DDLogicalThread *lt, DDMutex *m);
void ReportDeadlock(DDCallback *cb, DDMutex *m);
};
DDetector *DDetector::Create(const DDFlags *flags) {
(void)flags;
void *mem = MmapOrDie(sizeof(DD), "deadlock detector");
return new(mem) DD(flags);
}
DD::DD(const DDFlags *flags)
: flags(*flags) {
dd.clear();
}
DDPhysicalThread* DD::CreatePhysicalThread() {
return 0;
}
void DD::DestroyPhysicalThread(DDPhysicalThread *pt) {
}
DDLogicalThread* DD::CreateLogicalThread(u64 ctx) {
DDLogicalThread *lt = (DDLogicalThread*)InternalAlloc(sizeof(*lt));
lt->ctx = ctx;
lt->dd.clear();
lt->report_pending = false;
return lt;
}
void DD::DestroyLogicalThread(DDLogicalThread *lt) {
lt->~DDLogicalThread();
InternalFree(lt);
}
void DD::MutexInit(DDCallback *cb, DDMutex *m) {
m->id = 0;
m->stk = cb->Unwind();
}
void DD::MutexEnsureID(DDLogicalThread *lt, DDMutex *m) {
if (!dd.nodeBelongsToCurrentEpoch(m->id))
m->id = dd.newNode(reinterpret_cast<uptr>(m));
dd.ensureCurrentEpoch(<->dd);
}
void DD::MutexBeforeLock(DDCallback *cb,
DDMutex *m, bool wlock) {
DDLogicalThread *lt = cb->lt;
if (lt->dd.empty()) return; if (dd.hasAllEdges(<->dd, m->id)) return; SpinMutexLock lk(&mtx);
MutexEnsureID(lt, m);
if (dd.isHeld(<->dd, m->id))
return; if (dd.onLockBefore(<->dd, m->id)) {
dd.addEdges(<->dd, m->id, cb->Unwind(), cb->UniqueTid());
ReportDeadlock(cb, m);
}
}
void DD::ReportDeadlock(DDCallback *cb, DDMutex *m) {
DDLogicalThread *lt = cb->lt;
uptr path[10];
uptr len = dd.findPathToLock(<->dd, m->id, path, ARRAY_SIZE(path));
CHECK_GT(len, 0U); CHECK_EQ(m->id, path[0]);
lt->report_pending = true;
DDReport *rep = <->rep;
rep->n = len;
for (uptr i = 0; i < len; i++) {
uptr from = path[i];
uptr to = path[(i + 1) % len];
DDMutex *m0 = (DDMutex*)dd.getData(from);
DDMutex *m1 = (DDMutex*)dd.getData(to);
u32 stk_from = -1U, stk_to = -1U;
int unique_tid = 0;
dd.findEdge(from, to, &stk_from, &stk_to, &unique_tid);
rep->loop[i].thr_ctx = unique_tid;
rep->loop[i].mtx_ctx0 = m0->ctx;
rep->loop[i].mtx_ctx1 = m1->ctx;
rep->loop[i].stk[0] = stk_to;
rep->loop[i].stk[1] = stk_from;
}
}
void DD::MutexAfterLock(DDCallback *cb, DDMutex *m, bool wlock, bool trylock) {
DDLogicalThread *lt = cb->lt;
u32 stk = 0;
if (flags.second_deadlock_stack)
stk = cb->Unwind();
if (dd.onFirstLock(<->dd, m->id, stk))
return;
if (dd.onLockFast(<->dd, m->id, stk))
return;
SpinMutexLock lk(&mtx);
MutexEnsureID(lt, m);
if (wlock) CHECK(!dd.isHeld(<->dd, m->id));
if (!trylock)
dd.addEdges(<->dd, m->id, stk ? stk : cb->Unwind(), cb->UniqueTid());
dd.onLockAfter(<->dd, m->id, stk);
}
void DD::MutexBeforeUnlock(DDCallback *cb, DDMutex *m, bool wlock) {
dd.onUnlock(&cb->lt->dd, m->id);
}
void DD::MutexDestroy(DDCallback *cb,
DDMutex *m) {
if (!m->id) return;
SpinMutexLock lk(&mtx);
if (dd.nodeBelongsToCurrentEpoch(m->id))
dd.removeNode(m->id);
m->id = 0;
}
DDReport *DD::GetReport(DDCallback *cb) {
if (!cb->lt->report_pending)
return 0;
cb->lt->report_pending = false;
return &cb->lt->rep;
}
} #endif // #if SANITIZER_DEADLOCK_DETECTOR_VERSION == 1