These tests disable GC because of the potential for a deadlock, but
don't consider that a GC could be in progress due to other tests. The
likelihood of this case was increased when the minimum heap size was
lowered during the Go 1.18 cycle. The issue was then mitigated by
CL 368137 but in theory is always a problem.
This change is intended specifically for #45867, but I just walked over
a whole bunch of other tests that don't take this precaution where it
seems like it could be relevant (some tests it's not, like the
UserForcedGC test, or testprogs where no other code has run before it).
Fixes#45867.
Change-Id: I6a1b4ae73e05cab5a0b2d2cce14126bd13be0ba5
Reviewed-on: https://go-review.googlesource.com/c/go/+/369747
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: David Chase <drchase@google.com>
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
According to https://man7.org/linux/man-pages/man7/signal.7.html, the
default behavior of SIGIO is to terminate the program. The Go runtime
changes that behavior with its own signal handler, so the program will
terminate if we send the signal before the runtime has finished
setting up.
Fixes#49727
Change-Id: I65db66f5176831c8d7454eebc0138d825c68e100
Reviewed-on: https://go-review.googlesource.com/c/go/+/366255
Trust: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
the CgoPprof tests currently assume that calls to their cgoTraceback
functions are primarily for generating pprof samples and exit early
after receiving two calls.
This is a fragile assumption, as cgoTraceback will be called for _any_
signal received, hence why the test already looks for 2 calls instead of
1.
Still, this has caused flaky failures in two cases:
* #37201, where async preemption signals add additional probability of
receiving non-profiling signals. This was resolved by disabling async
preemption.
* #49401, where some ITIMER_PROF SIGPROF signals are ignored in favor of
per-thread SIGPROF signals.
Rather than attempting to keep plugging holes, this CL drops the fragile
assumption from these tests. Now they simply unconditionally run for the
full 1s before exiting.
Fixes#49401
Change-Id: I16dc9d2f16c2fb511e9db93dd096a402121f86ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/363634
Trust: Michael Pratt <mpratt@google.com>
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Rhys Hiltner <rhys@justin.tv>
Currently TestPhysicalMemoryUtilization can fail on systems with large
physical page sizes like 64 KiB because all the of the holes to be
scavenged are not aligned to the page size. The holes themselves are 64
KiB so this is actually quite likely.
Bump the size of the allocations for systems with larger physical page
sizes, and add additional slack to the threshold for unaligned pieces of
the holes that may be unaligned.
Fixes#49411.
Change-Id: Iafb35b8761dc9cdc53d3745c4771b1a64c5c97b5
Reviewed-on: https://go-review.googlesource.com/c/go/+/363415
Trust: Michael Knyszek <mknyszek@google.com>
Reviewed-by: David Chase <drchase@google.com>
Use C89 declaration. Also fix indentation.
Change-Id: Ib974eb32ac95610d0b0eca00ca3b139b388c73bd
Reviewed-on: https://go-review.googlesource.com/c/go/+/363356
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
When acquire a goroutine profile, we stop the world then acquire a
stack trace for each goroutine. When cgo traceback is used, the
traceback code may call the cgo traceback function using cgocall.
As the world is stopped, cgocall will be blocked at exitsyscall,
causing a deadlock. Bypass the scheduler (using asmcgocall) to fix
this.
Change-Id: Ic4e596adc3711310b6a983d73786d697ef15dd72
Reviewed-on: https://go-review.googlesource.com/c/go/+/362757
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This test changes TestPhysicalMemoryUtilization to be simpler, more
robust, and more honest about what's going on.
Fixes#49411.
Change-Id: I913ef055c6e166c104c62595c1597d44db62018c
Reviewed-on: https://go-review.googlesource.com/c/go/+/362978
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: David Chase <drchase@google.com>
A cgo file with "//export" declarations is not permitted to have function
definitions in the cgo comments.
Fixes#49188
Change-Id: I5c24b62b259871473ee984cea96a0edd7d42d23a
Reviewed-on: https://go-review.googlesource.com/c/go/+/359195
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
CL 64070 removed lockOSThread from the cgocall path, but didn't update
the signal-in-cgo detection in sighandler. As a result, signals that
arrive during a cgo call are treated like they arrived during Go
execution, breaking the traceback.
Update the cgo detection to fix the backtrace.
Fixes#47522
Change-Id: I61d77ba6465f55e3e6187246d79675ba8467ec23
Reviewed-on: https://go-review.googlesource.com/c/go/+/339989
Trust: Michael Pratt <mpratt@google.com>
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Many uses of Index/IndexByte/IndexRune/Split/SplitN
can be written more clearly using the new Cut functions.
Do that. Also rewrite to other functions if that's clearer.
For #46336.
Change-Id: I68d024716ace41a57a8bf74455c62279bde0f448
Reviewed-on: https://go-review.googlesource.com/c/go/+/351711
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Discover while working on moving checkptr instrumentation from walk to
SSA generation.
Change-Id: I3f4a41fe4ad308b86c7c57d14b6ccc7c613e7f98
Reviewed-on: https://go-review.googlesource.com/c/go/+/345432
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
When returning from Go to C, it was possible for the goroutine to be
preempted after calling unlockOSThread. This could happen when there
a context function installed by SetCgoTraceback set a non-zero context,
leading to a defer call in cgocallbackg1. The defer function wrapper,
introduced in 1.17 as part of the regabi support, was not nosplit,
and hence was a potential preemption point. If it did get preempted,
the G would move to a new M. It would then attempt to return to C
code on a different stack, typically leading to a SIGSEGV.
Fix this in a simple way by postponing the unlockOSThread until after
the other defer. Also check for the failure condition and fail early,
rather than waiting for a SIGSEGV.
Without the fix to cgocall.go, the test case fails about 50% of the
time on my laptop.
Fixes#47441
Change-Id: Ib8ca13215bd36cddc2a49e86698824a29c6a68ba
Reviewed-on: https://go-review.googlesource.com/c/go/+/338197
Trust: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Ironically, checkptrAlignment had a latent case of bad pointer
arithmetic: if ptr is nil, then `add(ptr, size-1)` might produce an
illegal pointer value.
The fix is to simply check for nil at the top of checkptrAlignment,
and short-circuit if so.
This CL also adds a more explicit bounds check in checkptrStraddles,
rather than relying on `add(ptr, size-1)` to wrap around. I don't
think this is necessary today, but it seems prudent to be careful.
Fixes#47430.
Change-Id: I5c50b2f7f41415dbebbd803e1b8e7766ca95e1fd
Reviewed-on: https://go-review.googlesource.com/c/go/+/338029
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This CL removes the unconditional OCHECKNIL check added in
walkUnsafeSlice by instead passing it as a pointer to
runtime.unsafeslice, and hiding the check behind a `len == 0` check.
While here, this CL also implements checkptr functionality for
unsafe.Slice and disallows use of unsafe.Slice with //go:notinheap
types.
Updates #46742.
Change-Id: I743a445ac124304a4d7322a7fe089c4a21b9a655
Reviewed-on: https://go-review.googlesource.com/c/go/+/331070
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Instead route through a C function, to avoid declaration conflicts
between the declaration needed in the cgo comment and the declaration
generated by cgo in _cgo_export.h.
This is not something user code will ever do, so no need to make it
work in cgo.
Fixes#46502
Change-Id: I1bfffdc76ef8ea63e3829871298d0774157957a5
Reviewed-on: https://go-review.googlesource.com/c/go/+/327309
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
The test harness waits for "ready" as a sign that the Go runtime has
installed its signal handler and is ready to be tested. But actually,
while LoadLibrary starts the loading of the Go runtime, it does so
asynchronously, so the "ready" sign is potentially premature and
certainly racy. However, all exported cgo entry points make a call to
_cgo_wait_runtime_init_done which waits for that asynchronous
initialization to complete. Therefore, this commit fixes the test to
call into the exported "Dummy" cgo function before emitting the "ready"
sign, so that we're sure the Go runtime is actually loaded.
Updates #45638.
Change-Id: I9b12b172d45bdcc09d54dd301de3a3e499544834
Reviewed-on: https://go-review.googlesource.com/c/go/+/321769
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
CL 211139 added TestLibraryCtrlHandler. But the CL left out import "C"
line in the test file that is supposed to be build with Cgo.
While debugging issue #45638, I discovered that the DLL built during
TestLibraryCtrlHandler does not have Dummy function. Adding import "C"
makes Dummy function appear in DLL function list.
TestLibraryCtrlHandler does not actually calls Dummy function. So I
don't see how this change affects issue #45638, but still let's make
this code correct.
Updates #45638
Change-Id: Ibab8fed29ef2ae446d0815842cf0bd040a5fb943
Reviewed-on: https://go-review.googlesource.com/c/go/+/313350
Trust: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
It sometimes seems to time out on slow systems, perhaps due to
being run at the same time as a lot of other work.
Also move the code to testdata/testprog, so that we don't have to
build it separately.
I hope that this
Fixes#35356
Change-Id: I875b858fa23836513ae14d3116461e22fffd5352
Reviewed-on: https://go-review.googlesource.com/c/go/+/312510
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
We add entries to the defer list at panic/goexit time on-the-fly for
frames with open-coded defers. We do this so that we can correctly
process open-coded defers and non-open-coded defers in the correct order
during panics/goexits. But we need to remove entries for open-coded
defers from the defer list when there is a recover, since those entries
may never get removed otherwise and will get stale, since their
corresponding defers may now be processed normally (inline).
This bug here is that we were only removing higher-up stale entries
during a recover if all defers in the current frame were done. But we
could have more defers in the current frame (as the new test case
shows). In this case, we need to leave the current defer entry around
for use by deferreturn, but still remove any stale entries further along
the chain.
For bug 43921, simple change that we should abort the removal loop for
any defer entry that is started (i.e. in process by a still
not-recovered outer panic), even if it is not an open-coded defer.
This change does not fix bug 43920, which looks to be a more complex fix.
Fixes#43882Fixes#43921
Change-Id: Ie05b2fa26973aa26b25c8899a2abc916090ee4f5
Reviewed-on: https://go-review.googlesource.com/c/go/+/286712
Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Trust: Dan Scales <danscales@google.com>
Fixes#41884
I can confirm this change fixes my issue.
I can't confirm that this doesn't break any and everything else.
I see that this code has been tweaked repeatedly, so I would really welcome guidance into further testing.
Change-Id: I1986dd0c2f30cfe10257f0d8c658988d6986f7a6
GitHub-Last-Rev: 92f02c9697
GitHub-Pull-Request: golang/go#41886
Reviewed-on: https://go-review.googlesource.com/c/go/+/261057
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
Trust: Alex Brainman <alex.brainman@gmail.com>
As part of #42026, these helpers from io/ioutil were moved to os.
(ioutil.TempFile and TempDir became os.CreateTemp and MkdirTemp.)
Update the Go tree to use the preferred names.
As usual, code compiled with the Go 1.4 bootstrap toolchain
and code vendored from other sources is excluded.
ReadDir changes are in a separate CL, because they are not a
simple search and replace.
For #42026.
Change-Id: If318df0216d57e95ea0c4093b89f65e5b0ababb3
Reviewed-on: https://go-review.googlesource.com/c/go/+/266365
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Currently, gentraceback decides which frames to print or elide when
unwinding inlined frames using only the name of the outermost
function. If the outermost function should be elided, then inlined
functions will also be elided, even if they shouldn't be.
This happens in practice in at least one situation. As of CL 258938,
exported Go functions (and functions they call) can now be inlined
into the generated _cgoexp_HASH_FN function. The runtime elides
_cgoexp_HASH_FN from tracebacks because it doesn't contain a ".".
Because of this bug, it also elides anything that was inlined into it.
This CL fixes this by synthesizing a funcInfo for the inlined
functions to pass to showframe.
Fixes#42754.
Change-Id: Ie6c663a4a1ac7f0d4beb1aa60bc26fc8cddd0f9d
Reviewed-on: https://go-review.googlesource.com/c/go/+/272131
Trust: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This moves the C part of the CrashTraceback test into its own file in
preparation for adding a test that transitions back into Go.
Change-Id: I9560dcfd80bf8a1d30809fd360f958f5261ebb01
Reviewed-on: https://go-review.googlesource.com/c/go/+/272130
Trust: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This reverts commit 3a81338622.
Reason for revert: Some edge cases not properly covered due to changes within runtime traceback generation since 2017, that need to be examined. This change landed very late in the Go1.16 cycle.
Change-Id: I8cf6f46ea0ef6161d878e79943e6c7cdac94bccf
Reviewed-on: https://go-review.googlesource.com/c/go/+/268577
Trust: Emmanuel Odeke <emmanuel@orijtech.com>
Run-TryBot: Emmanuel Odeke <emmanuel@orijtech.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This CL makes it so that instead of printing massive stack traces during
endless recursion, which spams users and aren't useful, it now prints out
the top and bottom 50 frames. If the number of frames <= 100
(_TracebackMaxFrames), we'll just print all the frames out.
Modified gentraceback to return counts of:
* ntotalframes
* nregularframes
which allows us to get accurate counts of the various kinds of frames.
While here, also fixed a bug that resulted from CL 37222, in which we
no longer accounted for decrementing requested frame skips, and assumed
that when printing, that skip would always be 0. The fix is instead to add
precondition that we'll only print if skip <= 0, but also decrement skip
as we iterate.
Fixes#7181.
Fixes#24628.
Change-Id: Ie31ec6413fdfbe43827b254fef7d99ea26a5277f
Reviewed-on: https://go-review.googlesource.com/c/go/+/37222
Run-TryBot: Emmanuel Odeke <emmanuel@orijtech.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Trust: Emmanuel Odeke <emmanuel@orijtech.com>
Otherwise, if a signal occurs just after we allocated the M,
we can deadlock if the signal handler needs to allocate an M
itself.
Fixes#42207
Change-Id: I76f44547f419e8b1c14cbf49bf602c6e645d8c14
Reviewed-on: https://go-review.googlesource.com/c/go/+/265759
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
The old ioutil references are still valid, but update our code
to reflect best practices and get used to the new locations.
Code compiled with the bootstrap toolchain
(cmd/asm, cmd/dist, cmd/compile, debug/elf)
must remain Go 1.4-compatible and is excluded.
Also excluded vendored code.
For #41190.
Change-Id: I6d86f2bf7bc37a9d904b6cee3fe0c7af6d94d5b1
Reviewed-on: https://go-review.googlesource.com/c/go/+/263142
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
The old os references are still valid, but update our code
to reflect best practices and get used to the new locations.
Code compiled with the bootstrap toolchain
(cmd/asm, cmd/dist, cmd/compile, debug/elf)
must remain Go 1.4-compatible and is excluded.
For #41190.
Change-Id: I8f9526977867c10a221e2f392f78d7dec073f1bd
Reviewed-on: https://go-review.googlesource.com/c/go/+/243907
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
checkptr has code to recognize &^ expressions, but it didn't take into
account that "p &^ x" gets rewritten to "p & ^x" during walk, which
resulted in false positive diagnostics.
This CL changes walkexpr to mark OANDNOT expressions with Implicit
when they're rewritten to OAND, so that walkCheckPtrArithmetic can
still recognize them later.
It would be slightly more idiomatic to instead mark the OBITNOT
expression as Implicit (as it's a compiler-generated Node), but the
OBITNOT expression might get constant folded. It's not worth the extra
complexity/subtlety of relying on n.Right.Orig, so we set Implicit on
the OAND node instead.
To atone for this transgression, I add documentation for nodeImplicit.
Fixes#40917.
Change-Id: I386304171ad299c530e151e5924f179e9a5fd5b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/249477
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
When run with stdin == /dev/null and stdout/stderr == pipe (i.e., as
os/exec.Command.CombinedOutput), GDB suffers from a bug
(https://sourceware.org/bugzilla/show_bug.cgi?id=26056) that causes
SIGSEGV when sent a SIGWINCH signal.
Package runtime tests TestEINTR and TestSignalDuringExec both send
SIGWINCH signals to the entire process group, thus including GDB if one
of the GDB tests is running in parallel.
TestEINTR only intends its signals for the current process, so it is
changed to do so. TestSignalDuringExec, really does want its signals to
go to children. However, it does not call t.Parallel(), so it won't run
at the same time as GDB tests.
This is a simple fix, but GDB is vulnerable, so we must be careful not
to add new parallel tests that send SIGWINCH to the entire process
group.
Fixes#39021
Change-Id: I803606fb000f08c65c1b10ec554d4ef6819e5dd5
Reviewed-on: https://go-review.googlesource.com/c/go/+/235557
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
A zombie slot is a slot that is marked, but isn't allocated. This can
indicate a bug in the GC, or a bad use of unsafe.Pointer. Currently,
the sweeper has best-effort detection for zombie slots: if there are
more marked slots than allocated slots, then there must have been a
zombie slot. However, this is imprecise since it only compares totals
and it reports almost no information that may be helpful to debug the
issue.
Add a precise check that compares the mark and allocation bitmaps and
reports detailed information if it detects a zombie slot.
No appreciable effect on performance as measured by the sweet
benchmarks:
name old time/op new time/op delta
BiogoIgor 15.8s ± 2% 15.8s ± 2% ~ (p=0.421 n=24+25)
BiogoKrishna 15.6s ± 2% 15.8s ± 5% ~ (p=0.082 n=22+23)
BleveIndexBatch100 4.90s ± 3% 4.88s ± 2% ~ (p=0.627 n=25+24)
CompileTemplate 204ms ± 1% 205ms ± 0% +0.22% (p=0.010 n=24+23)
CompileUnicode 77.8ms ± 2% 78.0ms ± 1% ~ (p=0.236 n=25+24)
CompileGoTypes 729ms ± 0% 731ms ± 0% +0.26% (p=0.000 n=24+24)
CompileCompiler 3.52s ± 0% 3.52s ± 1% ~ (p=0.152 n=25+25)
CompileSSA 8.06s ± 1% 8.05s ± 0% ~ (p=0.192 n=25+24)
CompileFlate 132ms ± 1% 132ms ± 1% ~ (p=0.373 n=24+24)
CompileGoParser 163ms ± 1% 164ms ± 1% +0.32% (p=0.003 n=24+25)
CompileReflect 453ms ± 1% 455ms ± 1% +0.39% (p=0.000 n=22+22)
CompileTar 181ms ± 1% 181ms ± 1% +0.20% (p=0.029 n=24+21)
CompileXML 244ms ± 1% 244ms ± 1% ~ (p=0.065 n=24+24)
CompileStdCmd 15.8s ± 2% 15.7s ± 2% ~ (p=0.059 n=23+24)
FoglemanFauxGLRenderRotateBoat 13.4s ±11% 12.8s ± 0% ~ (p=0.377 n=25+24)
FoglemanPathTraceRenderGopherIter1 18.6s ± 0% 18.6s ± 0% ~ (p=0.696 n=23+24)
GopherLuaKNucleotide 28.7s ± 4% 28.6s ± 5% ~ (p=0.700 n=25+25)
MarkdownRenderXHTML 250ms ± 1% 248ms ± 1% -1.01% (p=0.000 n=24+24)
[Geo mean] 1.60s 1.60s -0.11%
(https://perf.golang.org/search?q=upload:20200517.6)
For #38702.
Change-Id: I8af1fefd5fbf7b9cb665b98f9c4b73d1d08eea81
Reviewed-on: https://go-review.googlesource.com/c/go/+/234100
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
When a locked M wants to start a new M, it hands off to the template
thread to actually call clone and start the thread. The template thread
is lazily created the first time a thread is locked (or if cgo is in
use).
stoplockedm will release the P (_Pidle), then call handoffp to give the
P to another M. In the case of a pending STW, one of two things can
happen:
1. handoffp starts an M, which does acquirep followed by schedule, which
will finally enter _Pgcstop.
2. handoffp immediately enters _Pgcstop. This only occurs if the P has
no local work, GC work, and no spinning M is required.
If handoffp starts an M, and must create a new M to do so, then newm
will simply queue the M on newmHandoff for the template thread to do the
clone.
When a stop-the-world is required, stopTheWorldWithSema will start the
stop and then wait for all Ps to enter _Pgcstop. If the template thread
is not fully created because startTemplateThread gets stopped, then
another stoplockedm may queue an M that will never get created, and the
handoff P will never leave _Pidle. Thus stopTheWorldWithSema will wait
forever.
A sequence to trigger this hang when STW occurs can be visualized with
two threads:
T1 T2
------------------------------- -----------------------------
LockOSThread LockOSThread
haveTemplateThread == 0
startTemplateThread
haveTemplateThread = 1
newm haveTemplateThread == 1
preempt -> schedule g.m.lockedExt++
gcstopm -> _Pgcstop g.m.lockedg = ...
park g.lockedm = ...
return
... (any code)
preempt -> schedule
stoplockedm
releasep -> _Pidle
handoffp
startm (first 3 handoffp cases)
newm
g.m.lockedExt != 0
Add to newmHandoff, return
park
Note that the P in T2 is stuck sitting in _Pidle. Since the template
thread isn't running, the new M will not be started complete the
transition to _Pgcstop.
To resolve this, we disable preemption around the assignment of
haveTemplateThread and the creation of the template thread in order to
guarantee that if handTemplateThread is set then the template thread
will eventually exist, in the presence of stops.
Fixes#38931
Change-Id: I50535fbbe2f328f47b18e24d9030136719274191
Reviewed-on: https://go-review.googlesource.com/c/go/+/232978
Run-TryBot: Michael Pratt <mpratt@google.com>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This will hopefully address the occasional "runtime: out of memory"
failures observed on the openbsd-arm-jsing builder:
https://build.golang.org/log/c296d866e5d99ba401b18c1a2ff3e4d480e5238c
Also make the "spin" and "winch" loops concurrent instead of
sequential to cut down the test's running time.
Finally, change Block to coordinate by closing stdin instead of
sending SIGINT. The SIGINT handler wasn't necessarily registered by
the time the signal was sent.
Updates #20400
Updates #39043
Change-Id: Ie12fc75b87e33847dc25a12edb4126db27492da6
Reviewed-on: https://go-review.googlesource.com/c/go/+/234538
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
- Don't assume that a process interrupted at 100μs intervals will have
enough remaining time to make progress. (Stop sending signals
in between signal storms to allow the process to quiesce.)
- Don't assume that a child process that spins for 1ms will block long
enough for the parent process to receive signals or make meaningful
progress. (Instead, have the child block indefinitely, and unblock
it explicitly after the signal storm.)
For #39043
Updates #22838
Updates #20400
Change-Id: I85cba23498c346a637e6cfe8684ca0c478562a93
Reviewed-on: https://go-review.googlesource.com/c/go/+/233877
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Historically we've assumed that we can install all signal handlers
with the SA_RESTART flag set, and let the system restart slow functions
if a signal is received. Therefore, we don't have to worry about EINTR.
This is only partially true, and we've added EINTR checks already for
connect, and open/read on Darwin, and sendfile on Solaris.
Other cases have turned up in #36644, #38033, and #38836.
Also, #20400 points out that when Go code is included in a C program,
the C program may install its own signal handlers without SA_RESTART.
In that case, Go code will see EINTR no matter what it does.
So, go ahead and check for EINTR. We don't check in the syscall package;
people using syscalls directly may want to check for EINTR themselves.
But we do check for EINTR in the higher level APIs in os and net,
and retry the system call if we see it.
This change looks safe, but of course we may be missing some cases
where we need to check for EINTR. As such cases turn up, we can add
tests to runtime/testdata/testprogcgo/eintr.go, and fix the code.
If there are any such cases, their handling after this change will be
no worse than it is today.
For #22838Fixes#20400Fixes#36644Fixes#38033Fixes#38836
Change-Id: I7e46ca8cafed0429c7a2386cc9edc9d9d47a6896
Reviewed-on: https://go-review.googlesource.com/c/go/+/232862
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Fix TestFreeBSDNumCPU on newer versions of FreeBSD which have multi line
output from cpuset e.g.
cpuset -g -p 4141
pid 4141 mask: 0, 1, 2, 3, 4, 5, 6, 7, 8
pid 4141 domain policy: first-touch mask: 0, 1
The test now uses just the first line of output.
Fixes#38937Fixes#25924
Change-Id: If082ee6b82120ebde4dc437e58343b3dad69c65f
Reviewed-on: https://go-review.googlesource.com/c/go/+/232801
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Since we're sleeping rather than waiting for the goroutines,
let the goroutines run forever.
Fixes#38595
Change-Id: I4cd611fd7565f6e8d91e50c9273d91c514825314
Reviewed-on: https://go-review.googlesource.com/c/go/+/229484
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Clean up the code a little bit to make it clearer:
Don't check throwsplit for a SI_USER signal.
If throwsplit is set for a SigPanic signal, always throw;
discard any other flags.
Fixes#36420
Change-Id: Ic9dcd1108603d241f71c040504dfdc6e528f9767
Reviewed-on: https://go-review.googlesource.com/c/go/+/228900
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Variable 'procs' used to calculate the threshold of overuse in
TestPhysicalMemoryUtilization should be updated if GOMAXPROCS
gets changed, otherwise the threshold could be a large number,
making the test meaningless.
Change-Id: I876cbf11457529f56bae77af1e35f4538a721f95
Reviewed-on: https://go-review.googlesource.com/c/go/+/210297
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Make panics more useful by printing values, if their
underlying kind is printable, instead of just their memory address.
Thus now given any custom type derived from any of:
float*, int*, string, uint*
if we have panic with such a result, its value will be printed.
Thus given any of:
type MyComplex128 complex128
type MyFloat64 float64
type MyString string
type MyUintptr uintptr
panic(MyComplex128(32.1 + 10i))
panic(MyFloat64(-93.7))
panic(MyString("This one"))
panic(MyUintptr(93))
They will now print in the panic:
panic: main.MyComplex64(+1.100000e-001+3.000000e+000i)
panic: main.MyFloat64(-9.370000e+001)
panic: main.MyString("This one")
panic: main.MyUintptr(93)
instead of:
panic: (main.MyComplex128) (0xe0100,0x138cc0)
panic: (main.MyFloat64) (0xe0100,0x138068)
panic: (main.MyString) (0x48aa00,0x4c0840)
panic: (main.MyUintptr) (0xe0100,0x137e58)
and anything else will be printed as in the past with:
panic: (main.MyStruct) (0xe4ee0,0x40a0e0)
Also while here, updated the Go1.15 release notes.
Fixes#37531
Change-Id: Ia486424344a386014f2869ab3483e42a9ef48ac4
Reviewed-on: https://go-review.googlesource.com/c/go/+/221779
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
We had a few test cases to make sure checkptr didn't have certain
false positives, but none to test for any true positives. This CL
fixes that.
Updates #22218.
Change-Id: I24c02e469a4af43b1748829a9df325ce510f7cc4
Reviewed-on: https://go-review.googlesource.com/c/go/+/214238
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Currently, a block's control instruction gets the liveness info
of the last Value in the block. However, for an empty block, the
control instruction gets the invalid liveness info and therefore
not preemptible. One example is empty infinite loop, which has
only a control instruction. The control instruction being non-
preemptible makes the whole loop non-preemptible.
Fix this by using a different, preemptible liveness info for
empty block's control. We can choose an arbitrary preemptible
liveness info, as at run time we don't really use the liveness
map at that instruction.
As before, if the last Value in the block is non-preemptible, so
is the block control. For example, the conditional branch in the
write barrier test block is still non-preemptible.
Also, only update liveness info if we are actually emitting
instructions. So zero-width Values' liveness info (which are
always invalid) won't affect the block control's liveness info.
For example, if the last Values in a block is a tuple-generating
operation and a Select, the block control instruction is still
preemptible.
Fixes#35923.
Change-Id: Ic5225f3254b07e4955f7905329b544515907642b
Reviewed-on: https://go-review.googlesource.com/c/go/+/209659
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
TestPhysicalMemoryUtilization occasionally fails on some platforms by
only a small margin. The reason for this is that it assumes the
scavenger will always be able to scavenge all the memory that's released
by sweeping, but because of the page cache, there could be free and
unscavenged memory held onto by a P which the scavenger simply cannot
get to.
As a result, if the page cache gets filled completely (512 KiB of free
and unscavenged memory) this could skew a test which expects to
scavenge roughly 8 MiB of memory. More specifically, this is 512 KiB of
memory per P, and if a system is more inclined to bounce around
between Ps (even if there's only one goroutine), this memory can get
"stuck".
Through some experimentation, I found that failures correlated highly
with relatively large amounts of memory ending up in some page cache
(like 60 or 64 pages) on at least one P.
This change changes the test's threshold such that it accounts for the
page cache, and scales up with GOMAXPROCS. Because the test constants
themselves don't change, however, the test must now also bound
GOMAXPROCS such that the threshold doesn't get too high (at which point
the test becomes meaningless).
Fixes#35580.
Change-Id: I6bdb70706de991966a9d28347da830be4a19d3a1
Reviewed-on: https://go-review.googlesource.com/c/go/+/208377
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
In TestAsyncPreempt, the function being tested for preemption,
although still asynchronously preemptible, may have only samll
ranges of PCs that are preemtible. In an unlucky run, it may
take quite a while to have a signal that lands on a preemptible
instruction. The test case is kind of an extreme. Relax it to
make it more preemptible.
In the original version, the first closure has more work to do,
and it is not a leaf function, and the second test case is a
frameless leaf function. In the current version, the first one
is also a frameless leaf function (the atomic is intrinsified).
Add some calls to it. It is still not preemptible without async
preemption.
Fixes#35608.
Change-Id: Ia4f857f2afc55501c6568d7507b517e3b4db191c
Reviewed-on: https://go-review.googlesource.com/c/go/+/208221
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Frameless function is an interesting case for call injection
espcially for LR architectures. Extend the test for this case.
Change-Id: I074090d09eeaf642e71e3f44fea216f66d39b817
Reviewed-on: https://go-review.googlesource.com/c/go/+/202339
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Michael Anthony Knyszek
Bryan C. Mills
Michael Pratt
Cherry Mui
Cuong Manh Le
Russ Cox
Ian Lance Taylor
Matthew Dempsky
Jason A. Donenfeld
Alex Brainman
Prajwal Koirala
Dan Scales
Nuno Cruces
Austin Clements
Emmanuel Odeke
Tobias Klauser
Steven Hartland
Xiangdong Ji
Keith Randall
martin