delta/go-git.git/src/runtime/stack.go, branch dev.boringcrypto

all: gofmt main repo

2022-04-11T16:34:30+00:00

[This CL is part of a sequence implementing the proposal #51082.
The design doc is at https://go.dev/s/godocfmt-design.]

Run the updated gofmt, which reformats doc comments,
on the main repository. Vendored files are excluded.

For #51082.

Change-Id: I7332f099b60f716295fb34719c98c04eb1a85407
Reviewed-on: https://go-review.googlesource.com/c/go/+/384268
Reviewed-by: Jonathan Amsterdam 
Reviewed-by: Ian Lance Taylor

reflect, runtime: add reflect support for regabi on riscv64

2022-04-01T01:41:42+00:00

This CL adds regabi support needed for reflect and reimplement
of CL 360994, which is reverted.

Change-Id: I140673f09109dd9f72eff70aad64c0aa00d6857a
Reviewed-on: https://go-review.googlesource.com/c/go/+/396077
Reviewed-by: Cherry Mui 
Trust: mzh

Revert "reflect, runtime: add reflect support for regabi on riscv64"

2022-03-28T01:10:35+00:00

This reverts commit 56400fc70675cc2f404f33e3ed13386967cfe4da.

Reason for revert: this CL requires CL360296 be merged

Change-Id: I4c48c4d23b73b6e892cf86cbbc864698ebc5c992
Reviewed-on: https://go-review.googlesource.com/c/go/+/396076
Reviewed-by: Ian Lance Taylor 
Trust: mzh 
Run-TryBot: mzh 
TryBot-Result: Gopher Robot

reflect, runtime: add reflect support for regabi on riscv64

2022-03-27T12:55:16+00:00

This CL adds regabi support needed for reflect.

Change-Id: Ib78f8c7765f03e3a7b46e8b115bf8870b8076e6a
Reviewed-on: https://go-review.googlesource.com/c/go/+/360994
Trust: mzh 
Run-TryBot: mzh 
TryBot-Result: Gopher Robot 
Reviewed-by: Cherry Mui

all: gofmt -w -r 'interface{} -> any' src

2021-12-13T18:45:54+00:00

And then revert the bootstrap cmd directories and certain testdata.
And adjust tests as needed.

Not reverting the changes in std that are bootstrapped,
because some of those changes would appear in API docs,
and we want to use any consistently.
Instead, rewrite 'any' to 'interface{}' in cmd/dist for those directories
when preparing the bootstrap copy.

A few files changed as a result of running gofmt -w
not because of interface{} -> any but because they
hadn't been updated for the new //go:build lines.

Fixes #49884.

Change-Id: Ie8045cba995f65bd79c694ec77a1b3d1fe01bb09
Reviewed-on: https://go-review.googlesource.com/c/go/+/368254
Trust: Russ Cox 
Run-TryBot: Russ Cox 
Reviewed-by: Robert Griesemer 
TryBot-Result: Gopher Robot

runtime: fix racy stackForceMove check

2021-11-05T20:59:32+00:00

Currently, newstack loads gp.stackguard0 twice to check for different
poison values. The race window between these two checks can lead to
unintentional stack doubling, and ultimately to stack overflows.

Specifically, newstack checks if stackguard0 is stackPreempt first,
then it checks if it's stackForceMove. If stackguard0 is set to
stackForceMove on entry, but changes to stackPreempt between the two
checks, newstack will incorrectly double the stack allocation.

Fix this by loading stackguard0 exactly once and then checking it
against different poison values.

The effect of this is relatively minor because stackForceMove is only
used by a small number of runtime tests. I found this because
mayMorestackMove uses stackForceMove aggressively, which makes this
failure mode much more likely.

Change-Id: I1f8b6a6744e45533580a3f45d7030ec2ec65a5fb
Reviewed-on: https://go-review.googlesource.com/c/go/+/361775
Trust: Austin Clements 
Run-TryBot: Austin Clements 
TryBot-Result: Go Bot 
Reviewed-by: Cherry Mui 
Reviewed-by: Michael Pratt

runtime: add always-preempt maymorestack hook

2021-11-05T00:52:08+00:00

This adds a maymorestack hook that forces a preemption at every
possible cooperative preemption point. This would have helped us catch
several recent preemption-related bugs earlier, including #47302,
 #47304, and #47441.

For #48297.

Change-Id: Ib82c973589c8a7223900e1842913b8591938fb9f
Reviewed-on: https://go-review.googlesource.com/c/go/+/359796
Trust: Austin Clements 
Run-TryBot: Austin Clements 
TryBot-Result: Go Bot 
Reviewed-by: Cherry Mui 
Reviewed-by: Michael Pratt 
Reviewed-by: David Chase

runtime, syscall: add calls to asan functions

2021-11-02T05:35:11+00:00

Add explicit address sanitizer instrumentation to the runtime and
syscall packages. The compiler does not instrument the runtime
package. It does instrument the syscall package, but we need to add
a couple of cases that it can't see.

Refer to the implementation of the asan malloc runtime library,
this patch also allocates extra memory as the redzone, around the
returned memory region, and marks the redzone as unaddressable to
detect the overflows or underflows.

Updates #44853.

Change-Id: I2753d1cc1296935a66bf521e31ce91e35fcdf798
Reviewed-on: https://go-review.googlesource.com/c/go/+/298614
Run-TryBot: Ian Lance Taylor 
Reviewed-by: Ian Lance Taylor 
Trust: fannie zhang

runtime: track the amount of scannable allocated stack for the GC pacer

2021-10-29T18:35:20+00:00

This change adds two fields to gcControllerState: stackScan, used for
pacing decisions, and scannableStackSize, which directly tracks the
amount of space allocated for inuse stacks that will be scanned.

scannableStackSize is not updated directly, but is instead flushed from
each P when at an least 8 KiB delta has accumulated. This helps reduce
issues with atomics contention for newly created goroutines. Stack
growth paths are largely unaffected.

StackGrowth-48			51.4ns ± 0%	51.4ns ± 0%	~	(p=0.927 n=10+10)
StackGrowthDeep-48		6.14µs ± 3%	6.25µs ± 4%	~	(p=0.090 n=10+9)
CreateGoroutines-48		273ns ± 1%	273ns ± 1%	~	(p=0.676 n=9+10)
CreateGoroutinesParallel-48	65.5ns ± 5%	66.6ns ± 7%	~	(p=0.340 n=9+9)
CreateGoroutinesCapture-48	2.06µs ± 1%	2.07µs ± 4%	~	(p=0.217 n=10+10)
CreateGoroutinesSingle-48	550ns ± 3%	563ns ± 4%	+2.41%	(p=0.034 n=8+10)

For #44167.

Change-Id: Id1800d41d3a6c211b43aeb5681c57c0dc8880daf
Reviewed-on: https://go-review.googlesource.com/c/go/+/309589
Trust: Michael Knyszek 
Run-TryBot: Michael Knyszek 
TryBot-Result: Go Bot 
Reviewed-by: Michael Pratt

Revert "runtime: use unsafe.Slice in getStackMap"

2021-10-05T20:35:54+00:00

This reverts commit golang.org/cl/352953.

Reason for revert: unsafe.Slice is considerably slower.
Part of this is extra safety checks (good), but most of it
is the function call overhead. We should consider open-coding it (#48798).

Impact of this change:

name                   old time/op  new time/op  delta
StackCopyWithStkobj-8  12.1ms ± 5%  11.6ms ± 3%  -4.03%  (p=0.009 n=10+8)

Change-Id: Ib2448e3edac25afd8fb55ffbea073b8b11521bde
Reviewed-on: https://go-review.googlesource.com/c/go/+/354090
Trust: Josh Bleecher Snyder 
Run-TryBot: Josh Bleecher Snyder 
TryBot-Result: Go Bot 
Reviewed-by: Brad Fitzpatrick