This test was added to check new mutex profile functionality.
Specifically, it checks to make sure that the functionality behind
GODEBUG=runtimecontentionstacks works. The runtime currently tracks
contention from runtime-internal mutexes in mutex profiles, but it does
not record stack traces for them, attributing the time to a dummy
symbol. This GODEBUG enables collecting stacks.
Just disable the test. Even if this functionality breaks, it won't
affect Go users and it'll help keep the builders green. It's fine to
leave the test because this will be revisited in the next dev cycle.
For #64253.
Change-Id: I7938fe0f036fc4e4a0764f030e691e312ec2c9b5
Reviewed-on: https://go-review.googlesource.com/c/go/+/550775
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Eli Bendersky <eliben@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
Currently, lock ranking doesn't really try to model rwmutex. It records
the internal locks rLock and wLock, but in a subpar fashion:
1. wLock is held from lock to unlock, so it works OK, but it conflates
write locks of all rwmutexes as rwmutexW, rather than allowing
different rwmutexes to have different rankings.
2. rLock is an internal implementation detail that is only taken when
there is contention in rlock. As as result, the reader lock path is
almost never checked.
Add proper modeling. rwmutexR and rwmutexW remain as the ranks of the
internal locks, which have their own ordering. The new init method is
passed the ranks of the higher level lock that this represents, just
like lockInit for mutex.
execW ordered before MALLOC captures the case from #64722. i.e., there
can be allocation between BeforeFork and AfterFork.
For #64722.
Cq-Include-Trybots: luci.golang.try:gotip-linux-amd64-staticlockranking
Change-Id: I23335b28faa42fb04f1bc9da02fdf54d1616cd28
Reviewed-on: https://go-review.googlesource.com/c/go/+/549536
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Also use CompareAndSwap to make the code actually less racy.
Added a test which will be meaningful when run under the race
detector (tested it -race with broken fix in runtime, it failed).
Fixes#64649
Change-Id: I5972e08901d1adc8ba74858edad7eba91be1b0ce
Reviewed-on: https://go-review.googlesource.com/c/go/+/549796
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Mauri de Souza Meneguzzo <mauri870@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
This commit is aimed at improving the readability and consistency
of the code base. Extraneous newline characters were present after
some return statements, creating unnecessary separation in the code.
Fixes#64610
Change-Id: Ic1b05bf11761c4dff22691c2f1c3755f66d341f7
Reviewed-on: https://go-review.googlesource.com/c/go/+/548316
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
When generic function[a,b] is inlined to the same generic function[b,a]
with different types (not recursion) it is expected to get a pprof with
a single Location with two functions. However due to incorrect check
for generics names using runtime.Frame.Function, the profileBuilder
assumes it is a recursion and emits separate Location.
This change fixes the recursion check for generics functions by using
runtime_expandFinalInlineFrame
Fixes#64641
Change-Id: I3f58818f08ee322b281daa377fa421555ad328c9
Reviewed-on: https://go-review.googlesource.com/c/go/+/549135
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Use a GODEBUG to choose which certificate policy field to use. If
x509usepolicies=1 is set, use the Policies field, otherwise use the
PolicyIdentifiers field.
Fixes#64248
Change-Id: I3f0b56102e0bac4ebe800497717c61c58ef3f092
Reviewed-on: https://go-review.googlesource.com/c/go/+/546916
Reviewed-by: Damien Neil <dneil@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
profileBuilder is using Frame->Function as key for checking if we already
emitted a function. However for generics functions it has dots there [...],
so sometimes for different functions with different generics types,
the profileBuilder emits wrong functions.
Fixes#64528
Change-Id: I8b39245e0b18f4288ce758c912c6748f87cba39a
Reviewed-on: https://go-review.googlesource.com/c/go/+/546815
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
The pointer stored in mspan.largeType is an invalid pointer when
the span is an arena. We need to make sure that pointer isn't seen
by the garbage collector, as it might barf on it. Make sure we
zero the pointer using a uintptr write so the old value isn't picked
up by the write barrier.
The mspan.largeType field itself is in a NotInHeap struct, so a heap
scan won't find it. The only way we find it is when writing it, or
when reading it and putting it in a GC-reachable location. I think we
might need to audit the runtime to make sure these pointers aren't
being passed in places where the GC might (non-conservatively) scan a
stack frame it lives in. (It might be ok, many such places are either
systemstack or nosplit.)
Change-Id: Ie059d054e0da4d48a4c4b3be88b8e1e46ffa7d10
Reviewed-on: https://go-review.googlesource.com/c/go/+/548535
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Callers should be using math/rand/v2.Uint64 instead,
but there are lots of linkname references to runtime.fastrand
in public code. If we break it all now, that will require people
to use //go:build tags to use rand/v2.Uint64 with Go 1.22
and keep using the linkname for earlier versions.
Instead, leave the linkname working and then we can remove
it in Go 1.24, at which point everyone should be able to use
math/rand/v2.Uint64 unconditionally.
Change-Id: I7287ca4f67c270b009562313661cc28a4c2219a4
Reviewed-on: https://go-review.googlesource.com/c/go/+/548235
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Russ Cox <rsc@golang.org>
This is a partial revert of CL 483137.
CL 483137 started checking errors in postDecode, which is good. Now we
can catch more malformed pprof protos. However this made
TestEmptyProfile fail, so an early return was added when the profile was
"empty" (no samples).
Unfortunately, this was problematic. Profiles with no samples can still
be valid, but skipping postDecode meant that the resulting Profile was
missing values from the string table. In particular, net/http/pprof
needs to parse empty profiles in order to pass through the sample and
period types to a final output proto. CL 483137 broke this behavior.
internal/profile.Parse is only used in two places: in cmd/compile to
parse PGO pprof profiles, and in net/http/pprof to parse before/after
pprof profiles for delta profiles. In both cases, the input is never
literally empty (0 bytes). Even a pprof proto with no samples still
contains some header fields, such as sample and period type. Upstream
github.com/google/pprof/profile even has an explicit error on 0 byte
input, so `go tool pprof` will not support such an input.
Thus TestEmptyProfile was misleading; this profile doesn't need to
support empty input at all.
Resolve this by removing TestEmptyProfile and replacing it with an
explicit error on empty input, as upstream
github.com/google/pprof/profile has. For non-empty input, always run
postDecode to ensure the string table is processed.
TestConvertCPUProfileEmpty is reverted back to assert the values from
before CL 483137. Note that in this case "Empty" means no samples, not a
0 byte input.
Continue to allow empty files for PGO in order to minimize the chance of
last minute breakage if some users have empty files.
Fixes#64566.
Change-Id: I83a1f0200ae225ac6da0009d4b2431fe215b283f
Reviewed-on: https://go-review.googlesource.com/c/go/+/547996
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Adding explicit section headers makes it cleaner to split the profile
descriptions into multiple paragraphs, as there is now an explicit
transition from discussion of one profile type to the next.
For #14689.
Change-Id: Ifcff918367e91a165ee5f74423be3935b421972b
Reviewed-on: https://go-review.googlesource.com/c/go/+/547955
Reviewed-by: Rhys Hiltner <rhys@justin.tv>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
Amazingly, we seem to have nearly no in-tree documentation on the
semantics of block and mutex profiles. Add brief summaries, including
the new behavior from CL 506415 and CL 544195.
For #14689.
For #44920.
For #57071.
For #61015.
Change-Id: I1a6edce7c434fcb43f17c83eb362b1f9d1a32df1
Reviewed-on: https://go-review.googlesource.com/c/go/+/547057
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Rhys Hiltner <rhys@justin.tv>
Auto-Submit: Michael Pratt <mpratt@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
The exported API is only available with GOEXPERIMENT=rangefunc.
This will let Go 1.22 users who want to experiment with rangefuncs
access an efficient implementation of iter.Pull and iter.Pull2.
For #61897.
Change-Id: I6ef5fa8f117567efe4029b7b8b0f4d9b85697fb7
Reviewed-on: https://go-review.googlesource.com/c/go/+/543319
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
For #57071.
Change-Id: I7ce6c35bed95a6ea3cdc17007f861c5dd82404d2
Reviewed-on: https://go-review.googlesource.com/c/go/+/547056
Auto-Submit: Michael Pratt <mpratt@google.com>
Reviewed-by: Rhys Hiltner <rhys@justin.tv>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
profileruntimelocks is new in CL 544195, but the name is deceptive. Even
with profileruntimelocks=0, runtime-internal locks are still profiled.
The actual difference is that call stacks are not collected. Instead all
contention is reported at runtime._LostContendedLock.
Rename this setting to runtimecontentionstacks to make its name more
aligned with its behavior.
In addition, for this release the default is profileruntimelocks=0,
meaning that users are fairly likely to encounter
runtime._LostContendedLock. Rename it to
runtime._LostContendedRuntimeLock in an attempt to make it more
intuitive that these are runtime locks, not locks in application code.
For #57071.
Change-Id: I38aac28b2c0852db643d53b1eab3f3bc42a43393
Reviewed-on: https://go-review.googlesource.com/c/go/+/547055
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Rhys Hiltner <rhys@justin.tv>
Go 1.21.1 and Go 1.22 have ceased working around an issue with Linux
kernel defaults for transparent huge pages that can result in excessive
memory overheads. (https://bugzilla.kernel.org/show_bug.cgi?id=93111)
Many Linux distributions disable huge pages altogether these days, so
this problem isn't quite as far-reaching as it used to be. Also, the
problem only affects Go programs with very particular memory usage
patterns.
That being said, because the runtime used to actively deal with this
problem (but with some unpredictable behavior), it's preventing users
that don't have a lot of control over their execution environment from
upgrading to Go beyond Go 1.20.
This change adds a GODEBUG to smooth over the transition. The GODEBUG
setting disables transparent huge pages for all heap memory on Linux,
which is much more predictable than restoring the old behavior.
Fixes#64332.
Change-Id: I73b1894337f0f0b1a5a17b90da1221e118e0b145
Reviewed-on: https://go-review.googlesource.com/c/go/+/547475
Reviewed-by: Michael Pratt <mpratt@google.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Make sure to alloc+copy large keys and values instead of aliasing them,
when they might be updated by a future assignment.
Fixes#64474
Change-Id: Ie2226a81cf3897e4e2ee24472f2966d397ace53f
Reviewed-on: https://go-review.googlesource.com/c/go/+/546515
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Mauri de Souza Meneguzzo <mauri870@gmail.com>
Let the fault thread to crash the program to make sure while gdb coredump file could see the correct backtrace in the number one thread in gdb.
Fixes#63277.
Change-Id: Ie4473f76f0feba596091433918bcd35a4ff7e11b
GitHub-Last-Rev: f4615c23f6
GitHub-Pull-Request: golang/go#63666
Reviewed-on: https://go-review.googlesource.com/c/go/+/536895
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
CL 546025 failed to check if mp.curg is nil, causing all sorts of
failures. It can very well be nil in this context.
For #64318.
Fixes#64507.
Change-Id: I4a95c3fa16d5e1dee8041394c4bdb9c6ba04f032
Reviewed-on: https://go-review.googlesource.com/c/go/+/546636
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
The GoSyscallBegin event is a signal for both the P and the G to enter a
syscall state for the trace parser. (Ps can't have their own event
because it's too hard to model. As soon as the P enters _Psyscall it can
get stolen out of it.) But there's a window in time between when that
event is emitted and when the P enters _Psyscall where the P's status
can get emitted. In this window the tracer will emit the wrong status:
Running instead of Syscall. Really any call into the tracer could emit a
status event for the P, but in this particular case it's when running a
safepoint function that explicitly emits an event for the P's status.
The fix is straightforward. The source-of-truth on syscall status is the
G's status, so the function that emits the P's status just needs to
check the status of any G attached to it. If it's in _Gsyscall, then the
tracer should emit a Syscall status for the P if it's in _Prunning.
Fixes#64318.
Change-Id: I3b0fb0d41ff578e62810b04fa5a3ef73e2929b0a
Reviewed-on: https://go-review.googlesource.com/c/go/+/546025
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
As per #62352 the invocation of vmmap may fail (very rarely) due to
a temporary lack of resources on the test runner machine. This PR
allows for retrying the invocation a fixed number of times before
giving up. This is because we suspect the failure is due to
sensible to retry.
Fixes: #62352
Change-Id: I51aa66b949753d8127cc307181b6ef32e91d5b05
Reviewed-on: https://go-review.googlesource.com/c/go/+/545935
Auto-Submit: Bryan Mills <bcmills@google.com>
Run-TryBot: Bryan Mills <bcmills@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
ReadMemStats has a few assertions it makes about the consistency of the
stats it's about to produce. Specifically, how those stats line up with
runtime-internal stats. These checks are generally useful, but crashing
just because some stats are wrong is a heavy price to pay.
For a long time this wasn't a problem, but very recently it became a
real problem. It turns out that there's real benign skew that can happen
wherein sysmon (which doesn't synchronize with a STW) generates a trace
event when tracing is enabled, and may mutate some stats while
ReadMemStats is running its checks.
Fix this by synchronizing with both sysmon and the tracer. This is a bit
heavy-handed, but better that than false positives.
Also, put the checks behind a debug mode. We want to reduce the risk of
backporting this change, and again, it's not great to crash just because
user-facing stats are off. Still, enable this debug mode during the
runtime tests so we don't lose quite as much coverage from disabling
these checks by default.
Fixes#64401.
Change-Id: I9adb3e5c7161d207648d07373a11da8a5f0fda9a
Reviewed-on: https://go-review.googlesource.com/c/go/+/545277
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Felix Geisendörfer <felix.geisendoerfer@datadoghq.com>
Most contention on the runtime locks inside semaphores is observed in
runtime.semrelease1, but it can also appear in runtime.semacquire1. When
examining contention profiles in TestRuntimeLockMetricsAndProfile, allow
call stacks that include either.
For #64253
Change-Id: Id4f16af5e9a28615ab5032a3197e8df90f7e382f
Reviewed-on: https://go-review.googlesource.com/c/go/+/544375
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Rhys Hiltner <rhys@justin.tv>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
The type of the data pointer field of a slice should be a pointer
to the element type, not a *uint8.
This ensures that the SSA value representing the slice's data pointer
can be spilled to the stack slot for the corresponding argument.
Before this change the types didn't match so we ended up spilling the
argument to an autotmp instead of to the dedicated argument slot.
Fixes#64414
Change-Id: I09ee39e93f05aee07e3eceb14e39736d7fd70a33
Reviewed-on: https://go-review.googlesource.com/c/go/+/545357
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: David Chase <drchase@google.com>
The exitsyscall path, since the introduction of the new execution
tracer, stores a just little bit more data in the exitsyscall stack
frame, causing a build failure from exceeding the nosplit limit with
'-N -l' set on all packages (like Delve does).
One of the paths through which this fails is "throw" from wirep, called
by a callee of exitsyscall. By switching to the systemstack on this
path, we can avoid hitting the nosplit limit, fixing the build. It's
also not totally unreasonable to switch to the systemstack for the
throws in this function, since the function has to be nosplit anyway. It
gives the throw path a bit more wiggle room to dump information than it
otherwise would have.
Fixes#64113.
Change-Id: I56e94e40614a202b8ac2fdc8b8b731493b74e5d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/544535
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
This is required by traceThreadDestroy, though it's not strictly
necessary in this case. The requirement to hold sched.lock comes from
the assumption that traceThreadDestroy is getting called when the thread
leaves the tracer's view, but in this case the extra m that dropm is
dropping never leaves the allm list. Nevertheless, traceThreadDestroy
requires it just as a safety measure, and that's reasonable. dropm is
generally rare on pthread platforms, so the extra lock acquire over this
short critical section (and only when tracing is enabled) is fine.
Change-Id: Ib631820963c74f2f087d14a0067d0441d75d6785
Reviewed-on: https://go-review.googlesource.com/c/go/+/544396
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Currently the wakeableSleep lock is placed just after timers in the
ranking, but it turns out the timers lock can never be held over a timer
func, so that's wrong. Meanwhile, wakeableSleep can acquire sched.lock.
wakeableSleep, as it turns out, doesn't have any dependencies -- it's
always acquired in a (mostly) regular goroutine context.
Change-Id: Icc8ea76a8b309fbaf0f02215f16e5f706d49cd95
Reviewed-on: https://go-review.googlesource.com/c/go/+/544395
TryBot-Bypass: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
semrelease may unblock a goroutine, but the act of unblocking a
goroutine may emit an event, which in turn may try to acquire trace.lock
again.
It's safe to release trace.lock in readTrace0 for this because all of
the state (one variable) it uses under the lock will be recomputed when
it reacquires the lock. There's also no other synchronization
requirement to hold trace.lock. This is just a mistake.
Change-Id: Iff6c6b02efa298ebed8e60cdf6539ec161d5ec48
Reviewed-on: https://go-review.googlesource.com/c/go/+/544178
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
There's a conceptual cycle between traceStackTable.lock and
allocation-related locks, but it can't happen in practice because the
caller guarantees that there are no more writers to the table at the
point that dump is called.
But if that's true, then the lock isn't necessary at all. It would be
difficult to model this quiesence in the lockrank mode, so just don't
hold the lock and expand the documentation of the dump method.
Change-Id: Id4db61363f075b7574135529915e8bd4f4f4c082
Reviewed-on: https://go-review.googlesource.com/c/go/+/544177
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
When I initially added the wasm code for these ops I did not saw that
wasm actually has the Cas operations implemented, although they are
merely pointer assignments since wasm is single threaded.
Now with a generic implementation for And/Or we can add wasm to the
build tags.
For #61395
Change-Id: I997dc90477c772882d6703df1b795dfc0d90a699
GitHub-Last-Rev: 92736a6e34
GitHub-Pull-Request: golang/go#64300
Reviewed-on: https://go-review.googlesource.com/c/go/+/544116
Run-TryBot: Mauri de Souza Meneguzzo <mauri870@gmail.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Variables in functions implemented in assembly should have the
same names as when they were defined. The names of some variables
in asan-related assembly functions do not follow the above rule,
which will cause the runtime test to fail. This CL fixes this issue.
Updates #64257
Change-Id: I261f4db807d25e460513ef1c92cd1b707cdd1a16
Reviewed-on: https://go-review.googlesource.com/c/go/+/543837
Run-TryBot: Fannie Zhang <Fannie.Zhang@arm.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
The v2 execution tracer has a rudimentary deadlock detector, but it's
based on an arbitrary threshold that an actually get hit even if there's
no deadlock. This ends up breaking tests sometimes, and it would be bad
if this just appeared in production logs.
Put this 'deadlock detector' behind a flag.
For #55317.
Change-Id: I286f0c05b3ac9600f4f2f9696065cac8bbd25f00
Reviewed-on: https://go-review.googlesource.com/c/go/+/544235
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Currently entersyscall_gcwait always emits a ProcStop event. Most of the
time, this is correct, since the thread that just put the P into
_Psyscall is the same one that is putting it into _Pgcstop. However it's
possible for another thread to steal the P, start running a goroutine,
and then enter another syscall, putting the P back into _Psyscall. In
this case ProcStop is incorrect; the P is getting stolen. This leads to
broken traces.
Fix this by always emitting a ProcSteal event from entersyscall_gcwait.
This means that most of the time a thread will be 'stealing' the proc
from itself when it enters this function, but that's theoretically fine.
A ProcSteal is really just a fancy ProcStop.
Well, it would be if the parser correctly handled a self-steal. This is
a minor bug that just never came up before, but it's an update order
error (the mState is looked up and modified, but then it's modified
again at the end of the function to match newCtx). There's really no
reason a self-steal shouldn't be allowed, so fix that up and add a test.
Change-Id: Iec3d7639d331e3f2d127f92ce50c2c4a7818fcd3
Reviewed-on: https://go-review.googlesource.com/c/go/+/544215
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
This is totally valid and always was, but the staticlockranking builder
started failing when the new execution tracer was enabled by default.
Change-Id: I011e7d86bd968b1251bcc4d74395633036753b00
Reviewed-on: https://go-review.googlesource.com/c/go/+/544319
Reviewed-by: Michael Pratt <mpratt@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Add runtime-internal locks to the mutex contention profile.
Store up to one call stack responsible for lock contention on the M,
until it's safe to contribute its value to the mprof table. Try to use
that limited local storage space for a relatively large source of
contention, and attribute any contention in stacks we're not able to
store to a sentinel _LostContendedLock function.
Avoid ballooning lock contention while manipulating the mprof table by
attributing to that sentinel function any lock contention experienced
while reporting lock contention.
Guard collecting real call stacks with GODEBUG=profileruntimelocks=1,
since the available data has mixed semantics; we can easily capture an
M's own wait time, but we'd prefer for the profile entry of each
critical section to describe how long it made the other Ms wait. It's
too late in the Go 1.22 cycle to make the required changes to
futex-based locks. When not enabled, attribute the time to the sentinel
function instead.
Fixes#57071
This is a roll-forward of https://go.dev/cl/528657, which was reverted
in https://go.dev/cl/543660
Reason for revert: de-flakes tests (reduces dependence on fine-grained
timers, correctly identifies contention on big-endian futex locks,
attempts to measure contention in the semaphore implementation but only
uses that secondary measurement to finish the test early, skips tests on
single-processor systems)
Change-Id: I31389f24283d85e46ad9ba8d4f514cb9add8dfb0
Reviewed-on: https://go-review.googlesource.com/c/go/+/544195
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Auto-Submit: Rhys Hiltner <rhys@justin.tv>
Run-TryBot: Rhys Hiltner <rhys@justin.tv>
Turns out after adding the generic implementation for And/Or we ended up
with duplicated ops that are exactly the same for arm.
Apologies for the oversight, this CL removes the redundant arm code and
adds arm to the generic build flags.
For #61395
Change-Id: Id5e5a5cf113774948f8e772592e898d0810ad1f6
GitHub-Last-Rev: 4d8c857d15
GitHub-Pull-Request: golang/go#64299
Reviewed-on: https://go-review.googlesource.com/c/go/+/544017
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
According to review, buildmode=shared has unfixed shortcomings and
should be considered legacy at this time. So only buildmode=plugin is
going to be added for loong64 which is a relatively new platform.
Change-Id: Iac0b9f57e4ee01755458e180bb24d1b2a146fdf0
Reviewed-on: https://go-review.googlesource.com/c/go/+/480878
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Run-TryBot: WANG Xuerui <git@xen0n.name>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: abner chenc <chenguoqi@loongson.cn>
Reviewed-by: Meidan Li <limeidan@loongson.cn>