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2021-07-01Merge release-20210628.0-19-g16b751b6c (automated)gVisor bot
2021-07-01Mix checklocks and atomic analyzers.Adin Scannell
This change makes the checklocks analyzer considerable more powerful, adding: * The ability to traverse complex structures, e.g. to have multiple nested fields as part of the annotation. * The ability to resolve simple anonymous functions and closures, and perform lock analysis across these invocations. This does not apply to closures that are passed elsewhere, since it is not possible to know the context in which they might be invoked. * The ability to annotate return values in addition to receivers and other parameters, with the same complex structures noted above. * Ignoring locking semantics for "fresh" objects, i.e. objects that are allocated in the local frame (typically a new-style function). * Sanity checking of locking state across block transitions and returns, to ensure that no unexpected locks are held. Note that initially, most of these findings are excluded by a comprehensive nogo.yaml. The findings that are included are fundamental lock violations. The changes here should be relatively low risk, minor refactorings to either include necessary annotations to simplify the code structure (in general removing closures in favor of methods) so that the analyzer can be easily track the lock state. This change additional includes two changes to nogo itself: * Sanity checking of all types to ensure that the binary and ast-derived types have a consistent objectpath, to prevent the bug above from occurring silently (and causing much confusion). This also requires a trick in order to ensure that serialized facts are consumable downstream. This can be removed with https://go-review.googlesource.com/c/tools/+/331789 merged. * A minor refactoring to isolation the objdump settings in its own package. This was originally used to implement the sanity check above, but this information is now being passed another way. The minor refactor is preserved however, since it cleans up the code slightly and is minimal risk. PiperOrigin-RevId: 382613300
2021-06-01Move sync generics to their own packagesTamir Duberstein
The presence of multiple packages in a single directory sometimes confuses `go mod`, producing output like: go: downloading gvisor.dev/gvisor v0.0.0-20210601174640-77dc0f5bc94d $GOMODCACHE/gvisor.dev/gvisor@v0.0.0-20210601174640-77dc0f5bc94d/pkg/linewriter/linewriter.go:21:2: found packages sync (aliases.go) and seqatomic (generic_atomicptr_unsafe.go) in $GOMODCACHE/gvisor.dev/gvisor@v0.0.0-20210601174640-77dc0f5bc94d/pkg/sync imports.go:67:2: found packages tcp (accept.go) and rcv (rcv_test.go) in $GOMODCACHE/gvisor.dev/gvisor@v0.0.0-20210601174640-77dc0f5bc94d/pkg/tcpip/transport/tcp PiperOrigin-RevId: 376956213
2021-04-28Fix typo of Syncutil to sync on sync packages READMEKoichi Shiraishi
Signed-off-by: Koichi Shiraishi <zchee.io@gmail.com>
2021-04-14Merge release-20210408.0-30-g5c1052b6b (automated)gVisor bot
2021-04-14[syserror] Remove syserror from go_marshalZach Koopmans
PiperOrigin-RevId: 368470656
2021-03-03Merge release-20210301.0-8-g3e69f5d08 (automated)gVisor bot
2021-03-03Add checklocks analyzer.Bhasker Hariharan
This validates that struct fields if annotated with "// checklocks:mu" where "mu" is a mutex field in the same struct then access to the field is only done with "mu" locked. All types that are guarded by a mutex must be annotated with // +checklocks:<mutex field name> For more details please refer to README.md. PiperOrigin-RevId: 360729328
2021-02-24Merge release-20210208.0-89-gba4dfa717 (automated)gVisor bot
2021-02-24Move //pkg/gate.Gate to //pkg/sync.Jamie Liu
- Use atomic add rather than CAS in every Gate method, which is slightly faster in most cases. - Implement Close wakeup using gopark/goready to avoid channel allocation. New benchmarks: name old time/op new time/op delta GateEnterLeave-12 16.7ns ± 1% 10.3ns ± 1% -38.44% (p=0.000 n=9+8) GateClose-12 50.2ns ± 8% 42.4ns ± 6% -15.44% (p=0.000 n=10+10) GateEnterLeaveAsyncClose-12 972ns ± 2% 640ns ± 7% -34.15% (p=0.000 n=9+10) PiperOrigin-RevId: 359336344
2021-02-18Merge release-20210208.0-73-gf80a857a4 (automated)gVisor bot
2021-02-18Bump build constraints to Go 1.18Michael Pratt
These are bumped to allow early testing of Go 1.17. Use will be audited closer to the 1.17 release. PiperOrigin-RevId: 358278615
2021-02-17Add gohacks.Slice/StringHeader.Jamie Liu
See https://github.com/golang/go/issues/19367 for rationale. Note that the upstream decision arrived at in that thread, while useful for some of our use cases, doesn't account for all of our SliceHeader use cases (we often use SliceHeader to extract pointers from slices in a way that avoids bounds checking and/or handles nil slices correctly) and also doesn't exist yet. PiperOrigin-RevId: 358071574
2021-01-28Internal change.Michael Pratt
PiperOrigin-RevId: 354327882
2020-12-11Remove existing nogo exceptions.Adin Scannell
PiperOrigin-RevId: 347047550
2020-12-10Merge release-20201130.0-74-g92ca72ecb (automated)gVisor bot
2020-12-09Add //pkg/sync:generic_atomicptrmap.Jamie Liu
AtomicPtrMap is a generic concurrent map from arbitrary keys to arbitrary pointer values. Benchmarks: name time/op StoreDelete/RWMutexMap-12 335ns ± 1% StoreDelete/SyncMap-12 705ns ± 3% StoreDelete/AtomicPtrMap-12 287ns ± 4% StoreDelete/AtomicPtrMapSharded-12 289ns ± 1% LoadOrStoreDelete/RWMutexMap-12 342ns ± 2% LoadOrStoreDelete/SyncMap-12 662ns ± 2% LoadOrStoreDelete/AtomicPtrMap-12 290ns ± 7% LoadOrStoreDelete/AtomicPtrMapSharded-12 293ns ± 2% LookupPositive/RWMutexMap-12 101ns ±26% LookupPositive/SyncMap-12 202ns ± 2% LookupPositive/AtomicPtrMap-12 71.1ns ± 2% LookupPositive/AtomicPtrMapSharded-12 73.2ns ± 1% LookupNegative/RWMutexMap-12 119ns ± 1% LookupNegative/SyncMap-12 154ns ± 1% LookupNegative/AtomicPtrMap-12 84.7ns ± 3% LookupNegative/AtomicPtrMapSharded-12 86.8ns ± 1% Concurrent/FixedKeys_1PercentWrites_RWMutexMap-12 1.32µs ± 2% Concurrent/FixedKeys_1PercentWrites_SyncMap-12 52.7ns ±10% Concurrent/FixedKeys_1PercentWrites_AtomicPtrMap-12 31.8ns ±20% Concurrent/FixedKeys_1PercentWrites_AtomicPtrMapSharded-12 24.0ns ±15% Concurrent/FixedKeys_10PercentWrites_RWMutexMap-12 860ns ± 3% Concurrent/FixedKeys_10PercentWrites_SyncMap-12 68.8ns ±20% Concurrent/FixedKeys_10PercentWrites_AtomicPtrMap-12 98.6ns ± 7% Concurrent/FixedKeys_10PercentWrites_AtomicPtrMapSharded-12 42.0ns ±25% Concurrent/FixedKeys_50PercentWrites_RWMutexMap-12 1.17µs ± 3% Concurrent/FixedKeys_50PercentWrites_SyncMap-12 136ns ±34% Concurrent/FixedKeys_50PercentWrites_AtomicPtrMap-12 286ns ± 3% Concurrent/FixedKeys_50PercentWrites_AtomicPtrMapSharded-12 115ns ±35% Concurrent/ChangingKeys_1PercentWrites_RWMutexMap-12 1.27µs ± 2% Concurrent/ChangingKeys_1PercentWrites_SyncMap-12 5.01µs ± 3% Concurrent/ChangingKeys_1PercentWrites_AtomicPtrMap-12 38.1ns ± 3% Concurrent/ChangingKeys_1PercentWrites_AtomicPtrMapSharded-12 22.6ns ± 2% Concurrent/ChangingKeys_10PercentWrites_RWMutexMap-12 1.08µs ± 2% Concurrent/ChangingKeys_10PercentWrites_SyncMap-12 5.97µs ± 1% Concurrent/ChangingKeys_10PercentWrites_AtomicPtrMap-12 390ns ± 2% Concurrent/ChangingKeys_10PercentWrites_AtomicPtrMapSharded-12 93.6ns ± 1% Concurrent/ChangingKeys_50PercentWrites_RWMutexMap-12 1.77µs ± 2% Concurrent/ChangingKeys_50PercentWrites_SyncMap-12 8.07µs ± 2% Concurrent/ChangingKeys_50PercentWrites_AtomicPtrMap-12 1.61µs ± 2% Concurrent/ChangingKeys_50PercentWrites_AtomicPtrMapSharded-12 386ns ± 1% Updates #231 PiperOrigin-RevId: 346614776
2020-12-05Merge release-20201130.0-44-g8a45c8161 (automated)gVisor bot
2020-12-04Allow use of SeqAtomic with pointer-containing types.Jamie Liu
Per runtime.memmove, pointers are always copied atomically, as this is required by the GC. (Also, the init() safety check doesn't work because it gets renamed to <prefix>init() by template instantiation.) PiperOrigin-RevId: 345800302
2020-12-04Merge release-20201130.0-37-g6708c8c97 (automated)gVisor bot
2020-12-04Require sync.RWMutex to lock and unlock from the same goroutineMichael Pratt
This is the RWMutex equivalent to the preceding sync.Mutex CL. Updates #4804 PiperOrigin-RevId: 345681051
2020-12-03Merge release-20201130.0-25-ged8bdf461 (automated)gVisor bot
2020-12-02Consolidate most synchronization primitive linknames in the sync package.Jamie Liu
PiperOrigin-RevId: 345359823
2020-11-23Merge release-20201109.0-102-g3deb5d0c0 (automated)gVisor bot
2020-11-23Fix link against runtime.goyield.Adin Scannell
This function does not exist in Go 1.13. We need to add an adaptor to build against Go 1.13, which is the default Ubuntu version. PiperOrigin-RevId: 343929132
2020-11-19Merge release-20201109.0-89-g3454d5721 (automated)gVisor bot
2020-11-19Require sync.Mutex to lock and unlock from the same goroutineMichael Pratt
We would like to track locks ordering to detect ordering violations. Detecting violations is much simpler if mutexes must be unlocked by the same goroutine that locked them. Thus, as a first step to tracking lock ordering, add this lock/unlock requirement to gVisor's sync.Mutex. This is more strict than the Go standard library's sync.Mutex, but initial testing indicates only a single lock that is used across goroutines. The new sync.CrossGoroutineMutex relaxes the requirement (but will not provide lock order checking). Due to the additional overhead, enforcement is only enabled with the "checklocks" build tag. Build with this tag using: bazel build --define=gotags=checklocks ... From my spot-checking, this has no changed inlining properties when disabled. Updates #4804 PiperOrigin-RevId: 343370200
2020-09-02Merge release-20200818.0-112-g5c6601120 (automated)gVisor bot
2020-09-02Update Go version constraint on sync/spin_unsafe.go.Jamie Liu
PiperOrigin-RevId: 329801584
2020-09-02Merge release-20200818.0-111-g9bd016423 (automated)gVisor bot
2020-09-02Improve sync.SeqCount performance.Jamie Liu
- Make sync.SeqCountEpoch not a struct. This allows sync.SeqCount.BeginRead() to be inlined. - Mark sync.SeqAtomicLoad<T> nosplit to mitigate the Go compiler's refusal to inline it. (Best I could get was "cost 92 exceeds budget 80".) - Use runtime-guided spinning in SeqCount.BeginRead(). Benchmarks: name old time/op new time/op delta pkg:pkg/sync/sync goos:linux goarch:amd64 SeqCountWriteUncontended-12 8.24ns ± 0% 11.40ns ± 0% +38.35% (p=0.000 n=10+10) SeqCountReadUncontended-12 0.33ns ± 0% 0.14ns ± 3% -57.77% (p=0.000 n=7+8) pkg:pkg/sync/seqatomictest/seqatomic goos:linux goarch:amd64 SeqAtomicLoadIntUncontended-12 0.64ns ± 1% 0.41ns ± 1% -36.40% (p=0.000 n=10+8) SeqAtomicTryLoadIntUncontended-12 0.18ns ± 4% 0.18ns ± 1% ~ (p=0.206 n=10+8) AtomicValueLoadIntUncontended-12 0.27ns ± 3% 0.27ns ± 0% -1.77% (p=0.000 n=10+8) (atomic.Value.Load is, of course, inlined. We would expect an uncontended inline SeqAtomicLoad<int> to perform identically to SeqAtomicTryLoad<int>.) The "regression" in BenchmarkSeqCountWriteUncontended, despite this CL changing nothing in that path, is attributed to microarchitectural subtlety; the benchmark loop is unchanged except for its address: Before this CL: :0 0x4e62d1 48ffc2 INCQ DX :0 0x4e62d4 48399110010000 CMPQ DX, 0x110(CX) :0 0x4e62db 7e26 JLE 0x4e6303 :0 0x4e62dd 90 NOPL :0 0x4e62de bb01000000 MOVL $0x1, BX :0 0x4e62e3 f00fc118 LOCK XADDL BX, 0(AX) :0 0x4e62e7 ffc3 INCL BX :0 0x4e62e9 0fbae300 BTL $0x0, BX :0 0x4e62ed 733a JAE 0x4e6329 :0 0x4e62ef 90 NOPL :0 0x4e62f0 bb01000000 MOVL $0x1, BX :0 0x4e62f5 f00fc118 LOCK XADDL BX, 0(AX) :0 0x4e62f9 ffc3 INCL BX :0 0x4e62fb 0fbae300 BTL $0x0, BX :0 0x4e62ff 73d0 JAE 0x4e62d1 After this CL: :0 0x4e6361 48ffc2 INCQ DX :0 0x4e6364 48399110010000 CMPQ DX, 0x110(CX) :0 0x4e636b 7e26 JLE 0x4e6393 :0 0x4e636d 90 NOPL :0 0x4e636e bb01000000 MOVL $0x1, BX :0 0x4e6373 f00fc118 LOCK XADDL BX, 0(AX) :0 0x4e6377 ffc3 INCL BX :0 0x4e6379 0fbae300 BTL $0x0, BX :0 0x4e637d 733a JAE 0x4e63b9 :0 0x4e637f 90 NOPL :0 0x4e6380 bb01000000 MOVL $0x1, BX :0 0x4e6385 f00fc118 LOCK XADDL BX, 0(AX) :0 0x4e6389 ffc3 INCL BX :0 0x4e638b 0fbae300 BTL $0x0, BX :0 0x4e638f 73d0 JAE 0x4e6361 PiperOrigin-RevId: 329754148
2020-08-24Merge release-20200818.0-33-gab6c47421 (automated)gVisor bot
2020-08-24Bump build constraints to 1.17Michael Pratt
This enables pre-release testing with 1.16. The intention is to replace these with a nogo check before the next release. PiperOrigin-RevId: 328193911
2020-07-13Merge release-20200622.1-92-g9c32fd3f4 (automated)gVisor bot
2020-07-12Do not copy sleep.WakerGhanan Gowripalan
sleep.Waker's fields are modified as values. PiperOrigin-RevId: 320873451
2020-05-29Merge release-20200522.0-42-g65569cfc (automated)gVisor bot
2020-05-29Update Go version build tagsMichael Pratt
None of the dependencies have changed in 1.15. It may be possible to simplify some of the wrappers in rawfile following 1.13, but that can come in a later change. PiperOrigin-RevId: 313863264
2020-05-27Merge release-20200518.0-45-g0bc022b7 (automated)gVisor bot
2020-05-20Remove implicit dependencies for leaf packages.Rahat Mahmood
These packages don't actually use go_stateify or go_marshal, but end up implicitly dependent on the respective packages due to our build rules. These unnecessary dependencies make them unusuable in certain contexts due to circular dependency. PiperOrigin-RevId: 312595738
2020-05-07Merge release-20200422.0-51-g1f4087e (automated)gVisor bot
2020-04-02Merge release-20200323.0-57-g30388ff (automated)gVisor bot
2020-04-02Rename files in //pkg/sync to better reflect what they contain.Jamie Liu
PiperOrigin-RevId: 304447031
2020-03-25Merge release-20200219.0-224-gd04adeb (automated)gVisor bot
2020-03-25Fix data-race in endpoint.ReadinessBhasker Hariharan
PiperOrigin-RevId: 302924789
2020-02-06Merge release-20200127.0-85-g1b6a12a (automated)gVisor bot
2020-02-04Merge release-20200127.0-65-g95ce8bb (automated)gVisor bot
2020-01-27Standardize on tools directory.Adin Scannell
PiperOrigin-RevId: 291745021
2020-01-22Merge release-20200115.0-69-g6a59e7f (automated)gVisor bot
2020-01-21Rename DowngradableRWMutex to RWmutex.Ian Gudger
Also renames TMutex to Mutex. These custom mutexes aren't any worse than the standard library versions (same code), so having both seems redundant. PiperOrigin-RevId: 290873587
2020-01-22Merge release-20200115.0-68-gd0e75f2 (automated)gVisor bot
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