6 Commits

Author SHA1 Message Date
Dmitry Vyukov
7505cc301f tsan: remove tracking of racy addresses
We used to deduplicate based on the race address to prevent lots
of repeated reports about the same race.

But now we clear the shadow for the racy address in DoReportRace:

  // This prevents trapping on this address in future.
  for (uptr i = 0; i < kShadowCnt; i++)
    StoreShadow(&shadow_mem[i], i == 0 ? Shadow::kRodata : Shadow::kEmpty);

It should have the same effect of not reporting duplicates
(and actually better because it's automatically reset when the memory is reallocated).

So drop the address deduplication code. Both simpler and faster.

Reviewed By: melver

Differential Revision: https://reviews.llvm.org/D130240
2022-07-25 10:33:26 +02:00
Dmitry Vyukov
f831d6fc80 tsan: fix false positive during fd close
FdClose is a subjet to the same atomicity problem as MemoryRangeFreed
(memory state is not "monotoic" wrt race detection).
So we need to lock the thread slot in FdClose the same way we do
in MemoryRangeFreed.
This fixes the modified stress.cpp test.

Reviewed By: vitalybuka, melver

Differential Revision: https://reviews.llvm.org/D121143
2022-03-08 10:40:56 +01:00
Dmitry Vyukov
2eb3e20461 tsan: fix deadlock during race reporting
SlotPairLocker calls SlotLock under ctx->multi_slot_mtx.
SlotLock can invoke global reset DoReset if we are out of slots/epochs.
But DoReset locks ctx->multi_slot_mtx as well, which leads to deadlock.

Resolve the deadlock by removing SlotPairLocker/multi_slot_mtx
and only lock one slot for which we will do RestoreStack.
We need to lock that slot because RestoreStack accesses the slot journal.
But it's unclear why we need to lock the current slot.
Initially I did it just to be on the safer side (but at that time
we dit not lock the second slot, so it was easy just to lock the current slot).

Reviewed By: melver

Differential Revision: https://reviews.llvm.org/D116040
2021-12-20 18:52:48 +01:00
Dan Liew
d6a4294d13 Use standard separator for TSan options in stress.cpp test case.
Use of space as a separator for options is problematic for wrapper
scripts (i.e. implementations of `%run`) that have to marshall
environment variables to target different than the host.

Rather than requiring every implementation of `%run` to support spaces
in `TSAN_OPTIONS` it is simpler to fix this single test case.

rdar://83637067

Differential Revision: https://reviews.llvm.org/D110967
2021-10-02 21:11:18 -07:00
Dmitry Vyukov
34412cea5c tsan: don't use pipe2 in tests
MacOS buildbots failed:
stress.cpp:57:7: error: use of undeclared identifier 'pipe2'
https://green.lab.llvm.org/green//job/clang-stage1-RA/24209/consoleFull#-3468768778254eaf0-7326-4999-85b0-388101f2d404

Fix the test to not use pipe2.

Differential Revision: https://reviews.llvm.org/D110423
2021-09-24 17:52:16 +02:00
Dmitry Vyukov
124fcd7e9d tsan: add a stress test
The stress test does various assorted things
(memory accesses, function calls, atomic operations,
thread creation/join, intercepted libc calls)
in multiple threads just to stress various parts
of the runtime.

Reviewed By: melver

Differential Revision: https://reviews.llvm.org/D110416
2021-09-24 16:46:13 +02:00