Commit Graph

5205 Commits

Author SHA1 Message Date
Michael Pratt 86f6bf18b0 runtime: handle async fatal signals in VDSO
If we receive an async signal while running in the VDSO, such as a
SIGABRT or SIGSEGV sent from another process, we fail to print the
stacktrace with "runtime: unknown pc <vdso PC>".

We already have machinery to handle SIGPROF in the VDSO, but it isn't
hooked up for other signals. Add it to the general signal traceback
path.

This case is covered by TestSegv by making the test more strict w.r.t.
accepted output.

Fixes #47537

Change-Id: I755585f70e0c23e207e135bc6bd2aa68298e5d24
Reviewed-on: https://go-review.googlesource.com/c/go/+/339990
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>
2021-10-26 21:32:57 +00:00
Michael Pratt 091db6392d runtime: fix cgo signals detection
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>
2021-10-26 21:17:38 +00:00
Michael Pratt f8779b9e75 runtime: rename _m_ to mp [generated]
_g_, _p_, and _m_ are primarily vestiges of the C version of the
runtime, while today we prefer Go-style variable names (generally gp,
pp, and mp).

This change replaces all remaining uses of _m_ with mp. There are very
few remaining and all replacements are trivial.

[git-generate]
cd src/runtime

rf 'mv canpanic._m_ canpanic.mp'
GOOS=solaris \
  rf 'mv semasleep._m_ semasleep.mp'
GOOS=aix GOARCH=ppc64 \
  rf 'mv semasleep._m_ semasleep.mp'

Change-Id: I83690f7b4d4dc57557963100e9a2560ff343f3e8
Reviewed-on: https://go-review.googlesource.com/c/go/+/307813
Trust: Michael Pratt <mpratt@google.com>
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
2021-10-26 20:12:32 +00:00
Cuong Manh Le 283d8a3d53 all: use reflect.{Pointer,PointerTo}
Updates #47651
Updates #48665

Change-Id: I69a87b45a5cad7a07fbd855040cd9935cf874554
Reviewed-on: https://go-review.googlesource.com/c/go/+/358454
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: Brad Fitzpatrick <bradfitz@golang.org>
2021-10-26 14:24:17 +00:00
fanzha02 adfb85b315 runtime, runtime/asan: add asan runtime support
These are the runtime support functions for letting Go code interoperate
with the C/C++ address sanitizer. Calls to asanread/asanwrite are now
inserted by the compiler with the -asan option.  Calls to
asanunpoison/asanpoison will be from other runtime functions in a
subsequent CL.

Updates #44853.

Change-Id: I9e8fc0ce937828bc7f4a8b6637453ddc3862c47b
Reviewed-on: https://go-review.googlesource.com/c/go/+/298613
Trust: fannie zhang <Fannie.Zhang@arm.com>
Run-TryBot: fannie zhang <Fannie.Zhang@arm.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2021-10-26 01:22:47 +00:00
Michael Anthony Knyszek f99e40aac0 runtime: detangle gcPaceScavenger from the pacer
Currently gcPaceScavenger is called by gcControllerState.commit, but it
manipulates global state which precludes testing. This change detangles
the two.

Change-Id: I10d8ebdf426d99ba49d2f2cb4fb64891e9fd6091
Reviewed-on: https://go-review.googlesource.com/c/go/+/309272
Reviewed-by: Michael Pratt <mpratt@google.com>
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-10-21 18:20:19 +00:00
Michael Anthony Knyszek 6508fdad9d runtime: formalize and fix gcPercent synchronization
Currently gcController.gcPercent is read non-atomically by
gcControllerState.revise and gcTrigger.test, but these users may
execute concurrently with an update to gcPercent.

Although revise's results are best-effort, reading it directly in this
way is, generally speaking, unsafe.

This change makes gcPercent atomically updated for concurrent readers
and documents the complete synchronization semantics.

Because gcPercent otherwise only updated with the heap lock held or the
world stopped, all other reads can remain unsynchronized.

For #44167.

Change-Id: If09af103aae84a1e133e2d4fed8ab888d4b8f457
Reviewed-on: https://go-review.googlesource.com/c/go/+/308690
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>
2021-10-21 18:19:51 +00:00
emahiro 02a36668aa runtime: fix typo of pushBackAll
Fixes: #49081
Change-Id: Ie6742f1e7a60c2d92ce1283bcfaa3eac521440a1
Reviewed-on: https://go-review.googlesource.com/c/go/+/357629
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Trust: Daniel Martí <mvdan@mvdan.cc>
Trust: Cherry Mui <cherryyz@google.com>
2021-10-21 17:23:58 +00:00
Michael Anthony Knyszek 016d5eea11 runtime: retype mheap.reclaimCredit as atomic.Uintptr
[git-generate]
cd src/runtime
mv export_test.go export.go
GOROOT=$(dirname $(dirname $PWD)) rf '
  add mheap.reclaimCredit \
// reclaimCredit is spare credit for extra pages swept. Since \
// the page reclaimer works in large chunks, it may reclaim \
// more than requested. Any spare pages released go to this \
// credit pool. \
reclaimCredit_ atomic.Uintptr
  ex {
    import "runtime/internal/atomic"

    var t mheap
    var v, w uintptr
    var d uintptr

    t.reclaimCredit -> t.reclaimCredit_.Load()
    t.reclaimCredit = v -> t.reclaimCredit_.Store(v)
    atomic.Loaduintptr(&t.reclaimCredit) -> t.reclaimCredit_.Load()
    atomic.LoadAcquintptr(&t.reclaimCredit) -> t.reclaimCredit_.LoadAcquire()
    atomic.Storeuintptr(&t.reclaimCredit, v) -> t.reclaimCredit_.Store(v)
    atomic.StoreReluintptr(&t.reclaimCredit, v) -> t.reclaimCredit_.StoreRelease(v)
    atomic.Casuintptr(&t.reclaimCredit, v, w) -> t.reclaimCredit_.CompareAndSwap(v, w)
    atomic.Xchguintptr(&t.reclaimCredit, v) -> t.reclaimCredit_.Swap(v)
    atomic.Xadduintptr(&t.reclaimCredit, d) -> t.reclaimCredit_.Add(d)
  }
  rm mheap.reclaimCredit
  mv mheap.reclaimCredit_ mheap.reclaimCredit
'
mv export.go export_test.go

Change-Id: I2c567781a28f5d8c2275ff18f2cf605b82f22d09
Reviewed-on: https://go-review.googlesource.com/c/go/+/356712
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2021-10-20 20:39:36 +00:00
Michael Anthony Knyszek a91e976fd2 runtime: retype mheap.reclaimIndex as atomic.Uint64
[git-generate]
cd src/runtime
mv export_test.go export.go
GOROOT=$(dirname $(dirname $PWD)) rf '
  add mheap.reclaimIndex \
// reclaimIndex is the page index in allArenas of next page to \
// reclaim. Specifically, it refers to page (i % \
// pagesPerArena) of arena allArenas[i / pagesPerArena]. \
// \
// If this is >= 1<<63, the page reclaimer is done scanning \
// the page marks. \
reclaimIndex_ atomic.Uint64
  ex {
    import "runtime/internal/atomic"

    var t mheap
    var v, w uint64
    var d int64

    t.reclaimIndex -> t.reclaimIndex_.Load()
    t.reclaimIndex = v -> t.reclaimIndex_.Store(v)
    atomic.Load64(&t.reclaimIndex) -> t.reclaimIndex_.Load()
    atomic.LoadAcq64(&t.reclaimIndex) -> t.reclaimIndex_.LoadAcquire()
    atomic.Store64(&t.reclaimIndex, v) -> t.reclaimIndex_.Store(v)
    atomic.StoreRel64(&t.reclaimIndex, v) -> t.reclaimIndex_.StoreRelease(v)
    atomic.Cas64(&t.reclaimIndex, v, w) -> t.reclaimIndex_.CompareAndSwap(v, w)
    atomic.Xchg64(&t.reclaimIndex, v) -> t.reclaimIndex_.Swap(v)
    atomic.Xadd64(&t.reclaimIndex, d) -> t.reclaimIndex_.Add(d)
  }
  rm mheap.reclaimIndex
  mv mheap.reclaimIndex_ mheap.reclaimIndex
'
mv export.go export_test.go

Change-Id: I1d619e3ac032285b5f7eb6c563a5188c8e36d089
Reviewed-on: https://go-review.googlesource.com/c/go/+/356711
Reviewed-by: Austin Clements <austin@google.com>
Trust: Michael Knyszek <mknyszek@google.com>
2021-10-20 20:39:33 +00:00
Michael Anthony Knyszek 1dff8f0a05 runtime: retype mheap.pagesSweptBasis as atomic.Uint64
[git-generate]
cd src/runtime
mv export_test.go export.go
GOROOT=$(dirname $(dirname $PWD)) rf '
  add mheap.pagesSweptBasis pagesSweptBasis_ atomic.Uint64 // pagesSwept to use as the origin of the sweep ratio
  ex {
    import "runtime/internal/atomic"

    var t mheap
    var v, w uint64
    var d int64

    t.pagesSweptBasis -> t.pagesSweptBasis_.Load()
    t.pagesSweptBasis = v -> t.pagesSweptBasis_.Store(v)
    atomic.Load64(&t.pagesSweptBasis) -> t.pagesSweptBasis_.Load()
    atomic.LoadAcq64(&t.pagesSweptBasis) -> t.pagesSweptBasis_.LoadAcquire()
    atomic.Store64(&t.pagesSweptBasis, v) -> t.pagesSweptBasis_.Store(v)
    atomic.StoreRel64(&t.pagesSweptBasis, v) -> t.pagesSweptBasis_.StoreRelease(v)
    atomic.Cas64(&t.pagesSweptBasis, v, w) -> t.pagesSweptBasis_.CompareAndSwap(v, w)
    atomic.Xchg64(&t.pagesSweptBasis, v) -> t.pagesSweptBasis_.Swap(v)
    atomic.Xadd64(&t.pagesSweptBasis, d) -> t.pagesSweptBasis_.Add(d)
  }
  rm mheap.pagesSweptBasis
  mv mheap.pagesSweptBasis_ mheap.pagesSweptBasis
'
mv export.go export_test.go

Change-Id: Id9438184b9bd06d96894c02376385bad45dee154
Reviewed-on: https://go-review.googlesource.com/c/go/+/356710
Reviewed-by: Austin Clements <austin@google.com>
Trust: Michael Knyszek <mknyszek@google.com>
2021-10-20 20:39:29 +00:00
Michael Anthony Knyszek e90492882a runtime: retype mheap.pagesSwept as atomic.Uint64
[git-generate]
cd src/runtime
mv export_test.go export.go
GOROOT=$(dirname $(dirname $PWD)) rf '
  add mheap.pagesSwept pagesSwept_ atomic.Uint64 // pages swept this cycle
  ex {
    import "runtime/internal/atomic"

    var t mheap
    var v, w uint64
    var d int64

    t.pagesSwept -> t.pagesSwept_.Load()
    t.pagesSwept = v -> t.pagesSwept_.Store(v)
    atomic.Load64(&t.pagesSwept) -> t.pagesSwept_.Load()
    atomic.LoadAcq64(&t.pagesSwept) -> t.pagesSwept_.LoadAcquire()
    atomic.Store64(&t.pagesSwept, v) -> t.pagesSwept_.Store(v)
    atomic.StoreRel64(&t.pagesSwept, v) -> t.pagesSwept_.StoreRelease(v)
    atomic.Cas64(&t.pagesSwept, v, w) -> t.pagesSwept_.CompareAndSwap(v, w)
    atomic.Xchg64(&t.pagesSwept, v) -> t.pagesSwept_.Swap(v)
    atomic.Xadd64(&t.pagesSwept, d) -> t.pagesSwept_.Add(d)
  }
  rm mheap.pagesSwept
  mv mheap.pagesSwept_ mheap.pagesSwept
'
mv export.go export_test.go

Change-Id: Ife99893d90a339655f604bc3a64ee3decec645ea
Reviewed-on: https://go-review.googlesource.com/c/go/+/356709
Trust: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Austin Clements <austin@google.com>
2021-10-20 20:39:25 +00:00
Michael Anthony Knyszek d419a80bc7 runtime: retype mheap.pagesInUse as atomic.Uint64
[git-generate]
cd src/runtime
mv export_test.go export.go
GOROOT=$(dirname $(dirname $PWD)) rf '
  add mheap.pagesInUse \
// Proportional sweep \
// \
// These parameters represent a linear function from gcController.heapLive \
// to page sweep count. The proportional sweep system works to \
// stay in the black by keeping the current page sweep count \
// above this line at the current gcController.heapLive. \
// \
// The line has slope sweepPagesPerByte and passes through a \
// basis point at (sweepHeapLiveBasis, pagesSweptBasis). At \
// any given time, the system is at (gcController.heapLive, \
// pagesSwept) in this space. \
// \
// It is important that the line pass through a point we \
// control rather than simply starting at a 0,0 origin \
// because that lets us adjust sweep pacing at any time while \
// accounting for current progress. If we could only adjust \
// the slope, it would create a discontinuity in debt if any \
// progress has already been made. \
pagesInUse_ atomic.Uint64 // pages of spans in stats mSpanInUse
  ex {
    import "runtime/internal/atomic"

    var t mheap
    var v, w uint64
    var d int64

    t.pagesInUse -> t.pagesInUse_.Load()
    t.pagesInUse = v -> t.pagesInUse_.Store(v)
    atomic.Load64(&t.pagesInUse) -> t.pagesInUse_.Load()
    atomic.LoadAcq64(&t.pagesInUse) -> t.pagesInUse_.LoadAcquire()
    atomic.Store64(&t.pagesInUse, v) -> t.pagesInUse_.Store(v)
    atomic.StoreRel64(&t.pagesInUse, v) -> t.pagesInUse_.StoreRelease(v)
    atomic.Cas64(&t.pagesInUse, v, w) -> t.pagesInUse_.CompareAndSwap(v, w)
    atomic.Xchg64(&t.pagesInUse, v) -> t.pagesInUse_.Swap(v)
    atomic.Xadd64(&t.pagesInUse, d) -> t.pagesInUse_.Add(d)
  }
  rm mheap.pagesInUse
  mv mheap.pagesInUse_ mheap.pagesInUse
'
mv export.go export_test.go

Change-Id: I495d188683dba0778518563c46755b5ad43be298
Reviewed-on: https://go-review.googlesource.com/c/go/+/356549
Trust: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Austin Clements <austin@google.com>
2021-10-20 20:39:19 +00:00
Michael Anthony Knyszek 75b73d68b3 runtime: use atomic.Float64 for assist ratio
Change-Id: Ie7f09a7c9545ef9dd1860b1e332c4edbcbf8165e
Reviewed-on: https://go-review.googlesource.com/c/go/+/356170
Reviewed-by: Austin Clements <austin@google.com>
Trust: Michael Knyszek <mknyszek@google.com>
2021-10-20 20:38:59 +00:00
Michael Anthony Knyszek 3ec8d4b5ed runtime/internal/atomic: add atomic types for all functions
Change-Id: I74f365316484feb819c31c77fbffd78fadfe32a9
Reviewed-on: https://go-review.googlesource.com/c/go/+/356169
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
2021-10-20 20:38:47 +00:00
Benjamin Peterson 404f84d417 runtime: remove reference to crypto/tls GODEBUG usage
crypto/tls briefly used GODEBUG. That usage was removed in CL 191999.

Change-Id: I759b6f1b02db8160075cba30d73823018e19ad9d
GitHub-Last-Rev: 12d2a4a82b
GitHub-Pull-Request: golang/go#49012
Reviewed-on: https://go-review.googlesource.com/c/go/+/356313
Reviewed-by: Austin Clements <austin@google.com>
Trust: Michael Pratt <mpratt@google.com>
2021-10-19 17:12:53 +00:00
Meng Zhuo ee92daae25 runtime: ensure at least 1 tick between events
ticks might be same after tick division, although the real cputicks
is linear growth

Fixes #46737

Change-Id: I1d98866fbf21b426c6c1c96cc9cf802d7f440f18
Reviewed-on: https://go-review.googlesource.com/c/go/+/330849
Trust: Meng Zhuo <mzh@golangcn.org>
Trust: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Meng Zhuo <mzh@golangcn.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-10-19 07:45:46 +00:00
Michael Pratt 1b072b3ed5 runtime: consistently access pollDesc r/w Gs with atomics
Both netpollblock and netpollunblock read gpp using a non-atomic load.
When consuming a ready event, netpollblock clears gpp using a non-atomic
store, thus skipping a barrier.

Thus on systems with weak memory ordering, a sequence like so this is
possible:

             T1                                T2

1. netpollblock: read gpp -> pdReady
2. netpollblock: store gpp -> 0

                                 3. netpollunblock: read gpp -> pdReady
                                 4. netpollunblock: return

i.e., without a happens-before edge between (2) and (3), netpollunblock
may read the stale value of gpp.

Switch these access to use atomic loads and stores in order to create
these edges.

For ease of future maintainance, I've simply changed rg and wg to always
be accessed atomically, though I don't believe pollOpen or pollClose
require atomics today.

Fixes #48925

Change-Id: I903ea667eea320277610b4f969129935731520c3
Reviewed-on: https://go-review.googlesource.com/c/go/+/355952
Trust: Michael Pratt <mpratt@google.com>
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: David Chase <drchase@google.com>
2021-10-15 20:34:15 +00:00
Keith Randall 8331f25e96 reflect: make Elem panic on bad notinheap pointers
This CL fixes the subtle issue that Elem can promote a
not-in-heap pointer, which could be any bit pattern, into an
unsafe.Pointer, which the garbage collector can see. If that
resulting value is bad, it can crash the GC.

Make sure that we don't introduce bad pointers that way. We can
make Elem() panic, because any such bad pointers are in the Go heap,
and not-in-heap pointers are not allowed to point into the Go heap.

Update #48399

Change-Id: Ieaf35a611b16b4dfb5e907e229ed4a2aed30e18c
Reviewed-on: https://go-review.googlesource.com/c/go/+/350153
Trust: Keith Randall <khr@golang.org>
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2021-10-15 18:07:49 +00:00
Jay Conrod a37bebc042 cmd/go: stamp VCS revision and uncommitted status into binaries
When the go command builds a binary, it will now stamp the current
revision from the local Git or Mercurial repository, and it will also
stamp whether there are uncommitted edited or untracked files. Only
Git and Mercurial are supported for now.

If no repository is found containing the current working directory
(where the go command was started), or if either the main package
directory or the containing module's root directory is outside the
repository, no VCS information will be stamped. If the VCS tool is
missing or returns an error, that error is reported on the main
package (hinting that -buildvcs may be disabled).

This change introduces the -buildvcs flag, which is enabled by
default. When disabled, VCS information won't be stamped when it would
be otherwise.

Stamped information may be read using 'go version -m file' or
debug.ReadBuildInfo.

For #37475

Change-Id: I4e7d3159e1c270d85869ad99f10502e546e7582d
Reviewed-on: https://go-review.googlesource.com/c/go/+/353930
Trust: Jay Conrod <jayconrod@google.com>
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2021-10-14 18:44:37 +00:00
Jay Conrod 85a068fdf2 runtime/debug: add GoVersion to BuildInfo
BuildInfo now includes the version of Go used to build a binary, as
reported by runtime.Version() or 'go version'.

For #37475

Change-Id: Id07dda357dc70599d64a9202dab894c7288de1de
Reviewed-on: https://go-review.googlesource.com/c/go/+/353888
Trust: Jay Conrod <jayconrod@google.com>
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2021-10-14 18:44:21 +00:00
Jay Conrod 434cdd0337 debug/buildinfo: new package with Read and ReadFile
These functions provide access to module information stamped into Go
binaries. In the future, they'll provide access to other information
(like VCS info).

These functions are added in a new package instead of runtime/debug
since they use binary parsing packages like debug/elf, which would
make runtime/debug an unacceptably heavy dependency. The types in
runtime/debug are still used; debug/buildinfo uses them via type
aliases.

This information is already available for the running binary through
debug.ReadBuildInfo and for other binaries with 'go version -m', but
until now, there hasn't been a way to get it for other binaries
without installing cmd/go.

This change copies most of the code in cmd/go/internal/version. A
later CL will migrate 'go version -m' to use this package.

For #37475
Fixes #39301

Change-Id: I0fbe0896e04f12ef81c6d79fb61b20daede86159
Reviewed-on: https://go-review.googlesource.com/c/go/+/353887
Trust: Jay Conrod <jayconrod@google.com>
Run-TryBot: Jay Conrod <jayconrod@google.com>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2021-10-14 18:44:08 +00:00
Jay Conrod 765c9116be cmd/go: move module build info formatting into runtime/debug
Previously, modload.PackageBuildInfo returned a string containing
information about modules used to build an executable. This string is
embedded in the binary and can be read with debug.ReadBuildInfo or
'go version -m'.

With this change, debug.BuildInfo now has a MarshalText method that
returns a string in the same format as modload.PackageBuildInfo.

Package.load now calls Package.setBuildInfo, which constructs a
debug.BuildInfo, formats it with MarshalText, then sets
Package.Internal.BuildInfo. This is equivalent to what
modload.PackageBuildInfo did.

modload.PackageBuildInfo is deleted, since it's no longer used.

For #37475

Change-Id: I5875a98cb64737637fec2a450ab2ffa7f1805707
Reviewed-on: https://go-review.googlesource.com/c/go/+/353886
Trust: Jay Conrod <jayconrod@google.com>
Run-TryBot: Jay Conrod <jayconrod@google.com>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2021-10-14 18:43:59 +00:00
Matthew Dempsky 40f82f8a09 unsafe: optimize Slice bounds checking
This reduces the number of branches to bounds check non-empty slices
from 5 to 3. It does also increase the number of branches to handle
empty slices from 1 to 3; but for non-panicking calls, they should all
be predictable.

Updates #48798.

Change-Id: I3ffa66857096486f4dee417e1a66eb8fdf7a3777
Reviewed-on: https://go-review.googlesource.com/c/go/+/355490
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2021-10-13 18:15:48 +00:00
Matthew Dempsky 4efa216c9d unsafe: allow unsafe.Slice up to end of address space
Allow the user to construct slices that are larger than the Go heap as
long as they don't overflow the address space.

Updates #48798.

Change-Id: I659c8334d04676e1f253b9c3cd499eab9b9f989a
Reviewed-on: https://go-review.googlesource.com/c/go/+/355489
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2021-10-13 18:15:16 +00:00
Cherry Mui 2478b6f6d6 runtime: simplify multiple text section handling in findfunc
In findfunc, we first us the relative PC to find the function's
index in functab. When we split text sections, as the external
linker may shift the sections, and the PC may not match the
(virtual) PC we used to build the functab. So the index may be
inaccurate, and we need to do a (forward or backward) linear
search to find the actual entry.

Instead of using the PC directly, we can first compute the
(pre-external-link virtual) relative PC and use that to find the
index in functab. This way, the index will be accurate and we will
not need to do the special backward linear search.

Change-Id: I8ab11c66b7a5a3d79aae00198b98780e10db27b0
Reviewed-on: https://go-review.googlesource.com/c/go/+/354873
Trust: Cherry Mui <cherryyz@google.com>
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2021-10-11 15:48:29 +00:00
Keith Randall 16a3cefc93 runtime: fix uint64->float32 conversion for softfloat
The fix for #48807 in CL 354429 forgot that we also need to fix
the softfloat implementation.

Update #48807

Change-Id: I596fb4e14e78145d1ad43c130b2cc5122b73655c
Reviewed-on: https://go-review.googlesource.com/c/go/+/354613
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2021-10-08 17:58:41 +00:00
Cherry Mui 6436f5c13d runtime: handle end PC in textAddr
As the func table contains the end marker of the text section, we
sometimes need to get that address from an offset. Currently
textAddr doesn't handle that address, as it is not within any
text section. Instead of letting the callers not call textAddr
with the end offset, just handle it more elegantly in textAddr.

For #48837.

Change-Id: I6e97e455f6cb66e9680a7aac6152ba6f4cda2e12
Reviewed-on: https://go-review.googlesource.com/c/go/+/354635
Trust: Cherry Mui <cherryyz@google.com>
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2021-10-07 22:19:51 +00:00
Keith Randall 2043b3b47b cmd/compile,runtime: implement uint64->float32 correctly on 32-bit archs
The old way of implementing it, float32(float64(x)), involves 2 roundings
which can cause accuracy errors in some strange cases. Implement a runtime
version of [u]int64tofloat32 which only does one rounding.

Fixes #48807

Change-Id: Ie580be480bee4f3a479e58ef8dce23032f231704
Reviewed-on: https://go-review.googlesource.com/c/go/+/354429
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2021-10-07 18:34:24 +00:00
Meng Zhuo ecb2f231fa runtime,sync: using fastrandn instead of modulo reduction
fastrandn is ~50% faster than fastrand() % n.
`ack -v 'fastrand\(\)\s?\%'` finds all modulo on fastrand()

name              old time/op  new time/op  delta
Fastrandn/2       2.86ns ± 0%  1.59ns ± 0%  -44.35%  (p=0.000 n=9+10)
Fastrandn/3       2.87ns ± 1%  1.59ns ± 0%  -44.41%  (p=0.000 n=10+9)
Fastrandn/4       2.87ns ± 1%  1.58ns ± 1%  -45.10%  (p=0.000 n=10+10)
Fastrandn/5       2.86ns ± 1%  1.58ns ± 1%  -44.84%  (p=0.000 n=10+10)

Change-Id: Ic91f5ca9b9e3b65127bc34792b62fd64fbd13b5c
Reviewed-on: https://go-review.googlesource.com/c/go/+/353269
Trust: Meng Zhuo <mzh@golangcn.org>
Run-TryBot: Meng Zhuo <mzh@golangcn.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2021-10-07 14:01:52 +00:00
Josh Bleecher Snyder 8238f82bf1 runtime: streamline moduledata.textAddr
Accept a uint32 instead of a uintptr to make call sites simpler.

Do less work in the common case in which len(textsectmap) == 1.

Change-Id: Idd6cdc3fdad7a9356864c83790463b5d3000171b
Reviewed-on: https://go-review.googlesource.com/c/go/+/354132
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-10-06 20:29:59 +00:00
Josh Bleecher Snyder 058fa255bc cmd/link,runtime: make textsectmap fields more convenient for runtime
They're only used in a single place.
Instead of calculating the end every time,
calculate it in the linker.

It'd be nice to recalculate baseaddr-vaddr,
but that generates relocations that are too large.

While we're here, remove some pointless uintptr -> uintptr conversions.

Change-Id: I91758f9bff11b365bc3a63fee172dbdc3d90b966
Reviewed-on: https://go-review.googlesource.com/c/go/+/354089
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-10-06 19:54:45 +00:00
Russ Cox 4d8db00641 all: use bytes.Cut, strings.Cut
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>
2021-10-06 15:53:04 +00:00
Josh Bleecher Snyder e82ed0cd83 runtime: start moduledata memory load early
The slowest thing that can happen in funcdata is a cache miss
on moduledata.gofunc. Move that memory load earlier.

Also, for better ergonomics when working on this code,
do more calculations as uintptrs.

name                   old time/op  new time/op  delta
StackCopyWithStkobj-8  10.5ms ± 5%   9.9ms ± 4%  -6.03%  (p=0.000 n=15+15)

Change-Id: I590f4449725983c7f8d274c4ac7ed384d9018d85
Reviewed-on: https://go-review.googlesource.com/c/go/+/354134
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-10-05 23:36:43 +00:00
Josh Bleecher Snyder 2a5d4ea97e runtime: make funcspdelta inlineable
funcspdelta should be inlined: It is a tiny wrapper around another func.
The sanity check prevents that. Condition the sanity check on debugPcln.
While we're here, make the sanity check throw when it fails.

Change-Id: Iec022b8463b13a8e5a6d8479e7ddcb68909d6fe0
Reviewed-on: https://go-review.googlesource.com/c/go/+/354133
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-10-05 23:36:03 +00:00
Josh Bleecher Snyder 5758c40ac8 runtime: add a single-text-section fast path to findfunc
name                   old time/op  new time/op  delta
StackCopyWithStkobj-8  11.5ms ± 4%  10.7ms ± 7%  -7.10%  (p=0.000 n=10+10)

Change-Id: Ib806d732ec11f2a6cfde229fd88aff0fe68d9e7d
Reviewed-on: https://go-review.googlesource.com/c/go/+/354129
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-10-05 23:34:32 +00:00
Josh Bleecher Snyder 77bd0da688 cmd/link,runtime: remove unnecessary funcdata alignment
Change-Id: I2777feaae4f266de99b56b444045370c82447cff
Reviewed-on: https://go-review.googlesource.com/c/go/+/354011
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-10-05 23:25:24 +00:00
Josh Bleecher Snyder e31c9ab557 cmd/link,runtime: remove functab relocations
Use an offset from runtime.text instead.
This removes the last relocation from functab generation,
which lets us simplify that code.

size      before    after     Δ        %
addr2line 3680818   3652498   -28320   -0.769%
api       4944850   4892418   -52432   -1.060%
asm       4757586   4711266   -46320   -0.974%
buildid   2418546   2392578   -25968   -1.074%
cgo       4197346   4164818   -32528   -0.775%
compile   22076882  21875890  -200992  -0.910%
cover     4411362   4358418   -52944   -1.200%
dist      3091346   3062738   -28608   -0.925%
doc       3563234   3532610   -30624   -0.859%
fix       3020658   2991666   -28992   -0.960%
link      6164642   6110834   -53808   -0.873%
nm        3646818   3618482   -28336   -0.777%
objdump   4012594   3983042   -29552   -0.736%
pack      2153554   2128338   -25216   -1.171%
pprof     13011666  12870114  -141552  -1.088%
test2json 2383906   2357554   -26352   -1.105%
trace     9736514   9631186   -105328  -1.082%
vet       6655058   6580370   -74688   -1.122%
total     103927380 102914820 -1012560 -0.974%

relocs    before  after   Δ       %
addr2line 25069   22709   -2360   -9.414%
api       17176   13321   -3855   -22.444%
asm       18271   15630   -2641   -14.455%
buildid   9233    7352    -1881   -20.373%
cgo       16222   13044   -3178   -19.591%
compile   60421   46299   -14122  -23.373%
cover     18479   14526   -3953   -21.392%
dist      10135   7733    -2402   -23.700%
doc       12735   9940    -2795   -21.947%
fix       10820   8341    -2479   -22.911%
link      21849   17785   -4064   -18.600%
nm        24988   22642   -2346   -9.389%
objdump   26060   23462   -2598   -9.969%
pack      7665    5936    -1729   -22.557%
pprof     60764   50998   -9766   -16.072%
test2json 8389    6431    -1958   -23.340%
trace     37180   29382   -7798   -20.974%
vet       24044   19055   -4989   -20.749%
total     409499  334585  -74914  -18.294%


Caching the field size in debug/gosym.funcTab
avoids a 20% PCToLine performance regression.

name            old time/op    new time/op    delta
115/LineToPC-8    56.4µs ± 3%    57.3µs ± 2%  +1.66%  (p=0.006 n=15+13)
115/PCToLine-8     188ns ± 2%     190ns ± 3%  +1.46%  (p=0.030 n=15+15)


Change-Id: I2816a1b28e62b01852e3b306f08546f1e56cd5ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/352191
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-10-05 23:25:06 +00:00
Josh Bleecher Snyder 990c9c6cab Revert "runtime: use unsafe.Slice in getStackMap"
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 <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2021-10-05 20:35:54 +00:00
Josh Bleecher Snyder 113b52979f runtime: remove a branch from funcdata
name                   old time/op  new time/op  delta
StackCopyWithStkobj-8  12.1ms ± 7%  11.6ms ± 8%  -3.88%  (p=0.002 n=19+19)

Change-Id: Idf810017d541eba70bcf9c736267de9efae916d5
Reviewed-on: https://go-review.googlesource.com/c/go/+/354072
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-10-05 20:35:48 +00:00
Josh Bleecher Snyder 75773b0e7b runtime: add BenchmarkStackCopyWithStkobj
For benchmarking and improving recent stkobj-related changes.

Co-Authored-By: Cherry Mui <cherryyz@google.com>
Change-Id: I34c8b1a09e4cf98547460882b0d3908158269f57
Reviewed-on: https://go-review.googlesource.com/c/go/+/354071
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-10-05 20:35:41 +00:00
Josh Bleecher Snyder 3100dc1a7f cmd/link,runtime: remove relocations from stkobjs
Use an offset from go.func.* instead.
This removes the last relocation from funcdata symbols,
which lets us simplify that code.

size      before    after     Δ       %
addr2line 3683218   3680706   -2512   -0.068%
api       4951074   4944850   -6224   -0.126%
asm       4744258   4757586   +13328  +0.281%
buildid   2419986   2418546   -1440   -0.060%
cgo       4218306   4197346   -20960  -0.497%
compile   22132066  22076882  -55184  -0.249%
cover     4432834   4411362   -21472  -0.484%
dist      3111202   3091346   -19856  -0.638%
doc       3583602   3563234   -20368  -0.568%
fix       3023922   3020658   -3264   -0.108%
link      6188034   6164642   -23392  -0.378%
nm        3665826   3646818   -19008  -0.519%
objdump   4015234   4012450   -2784   -0.069%
pack      2155010   2153554   -1456   -0.068%
pprof     13044178  13011522  -32656  -0.250%
test2json 2402146   2383906   -18240  -0.759%
trace     9765410   9736514   -28896  -0.296%
vet       6681250   6655058   -26192  -0.392%
total     104217556 103926980 -290576 -0.279%

relocs    before  after   Δ       %
addr2line 25563   25066   -497    -1.944%
api       18409   17176   -1233   -6.698%
asm       18903   18271   -632    -3.343%
buildid   9513    9233    -280    -2.943%
cgo       17103   16222   -881    -5.151%
compile   64825   60421   -4404   -6.794%
cover     19464   18479   -985    -5.061%
dist      10798   10135   -663    -6.140%
doc       13503   12735   -768    -5.688%
fix       11465   10820   -645    -5.626%
link      23214   21849   -1365   -5.880%
nm        25480   24987   -493    -1.935%
objdump   26610   26057   -553    -2.078%
pack      7951    7665    -286    -3.597%
pprof     63964   60761   -3203   -5.008%
test2json 8735    8389    -346    -3.961%
trace     39639   37180   -2459   -6.203%
vet       25970   24044   -1926   -7.416%
total     431108  409489  -21619  -5.015%

Change-Id: I43c26196a008da6d1cb3a782eea2f428778bd569
Reviewed-on: https://go-review.googlesource.com/c/go/+/353138
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-10-05 19:16:08 +00:00
Josh Bleecher Snyder 017ffcd10d cmd/link, runtime: convert FUNCDATA relocations to offsets
Every function has associated numbered extra funcdata to another symbol.
Prior to this change, a funcdata pointer was stored as a relocation.

This change alters this to be an offset relative to go.func.* or go.funcrel.*.

This reduces the number of relocations on darwin/arm64 by about 40%.
It also shrinks externally linked binaries. On darwin/arm64:

size      before    after     Δ        %
addr2line 3788498   3699730   -88768   -2.343%
api       5100018   4951074   -148944  -2.920%
asm       4855234   4744274   -110960  -2.285%
buildid   2500162   2419986   -80176   -3.207%
cgo       4338258   4218306   -119952  -2.765%
compile   22764418  22132226  -632192  -2.777%
cover     4583186   4432770   -150416  -3.282%
dist      3200962   3094626   -106336  -3.322%
doc       3680402   3583602   -96800   -2.630%
fix       3114914   3023922   -90992   -2.921%
link      6308578   6154786   -153792  -2.438%
nm        3754338   3665826   -88512   -2.358%
objdump   4124738   4015234   -109504  -2.655%
pack      2232626   2155010   -77616   -3.476%
pprof     13497474  13044066  -453408  -3.359%
test2json 2483810   2402146   -81664   -3.288%
trace     10108898  9748802   -360096  -3.562%
vet       6884322   6681314   -203008  -2.949%
total     107320836 104167700 -3153136 -2.938%

relocs    before  after   Δ       %
addr2line 33357   25563   -7794   -23.365%
api       31589   18409   -13180  -41.723%
asm       27825   18904   -8921   -32.061%
buildid   15603   9513    -6090   -39.031%
cgo       27809   17103   -10706  -38.498%
compile   114769  64829   -49940  -43.513%
cover     32932   19462   -13470  -40.902%
dist      18797   10796   -8001   -42.565%
doc       22891   13503   -9388   -41.012%
fix       19700   11465   -8235   -41.802%
link      37324   23198   -14126  -37.847%
nm        33226   25480   -7746   -23.313%
objdump   35237   26610   -8627   -24.483%
pack      13535   7951    -5584   -41.256%
pprof     97986   63961   -34025  -34.724%
test2json 15113   8735    -6378   -42.202%
trace     66786   39636   -27150  -40.652%
vet       43328   25971   -17357  -40.060%
total     687806  431088  -256718 -37.324%

It should also incrementally speed up binary launching
and may reduce linker memory use.

This is another step towards removing relocations so
that pages that were previously dirtied by the loader may remain clean,
which will offer memory savings useful in constrained environments like iOS.

Removing the relocations in .stkobj symbols will allow some simplifications.
There will be no references into go.funcrel.*,
so we will no longer need to use the bottom bit to distinguish offset bases.

Change-Id: I83d34c1701d6f3f515b9905941477d522441019d
Reviewed-on: https://go-review.googlesource.com/c/go/+/352110
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-10-05 15:47:57 +00:00
Lynn Boger 7983830423 runtime: add ABIInternal to strhash and memhash on ppc64x
In testing the register ABI changes I found that the benchmarks
for strhash and memhash degraded unless I marked them as
ABIInternal. This fixes that.

Change-Id: I9c7a04eaa6a66b888877f43454c51277c07e638a
Reviewed-on: https://go-review.googlesource.com/c/go/+/353832
Reviewed-by: Cherry Mui <cherryyz@google.com>
Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
2021-10-05 14:12:44 +00:00
Josh Bleecher Snyder c2483a5c03 cmd, runtime: eliminate runtime.no_pointers_stackmap
runtime.no_pointers_stackmap is an odd beast.
It is defined in a Go file, populated by assembly,
used by the GC, and its address is magic used
by async pre-emption to ascertain whether a
routine was implemented in assembly.

A subsequent change will force all GC data into the go.func.* linker symbol.
runtime.no_pointers_stackmap is GC data, so it must go there.
Yet it also needs to go into rodata, for the runtime address trick.

This change eliminates it entirely.

Replace the runtime address check with the newly introduced asm funcflag.

Handle the assembly macro as magic, similarly to our handling of go_args_stackmap.
This allows the no_pointers_stackmap to be identical in all ways
to other gclocals stackmaps, including content-addressability.

Change-Id: Id2f20a262cfab0719beb88e6342984ec4b196268
Reviewed-on: https://go-review.googlesource.com/c/go/+/353672
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-10-04 22:45:17 +00:00
Josh Bleecher Snyder 752cc07c77 cmd, runtime: mark assembly routines in FuncFlags
There's no good way to ascertain at runtime whether
a function was implemented in assembly.
The existing workaround doesn't play nicely
with some upcoming linker changes.

This change introduces an explicit marker for routines
implemented in assembly.

This change doesn't use the new bit anywhere,
it only introduces it.

Change-Id: I4051dc0afc15b260724a04b9d18aeeb94911bb29
Reviewed-on: https://go-review.googlesource.com/c/go/+/353671
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-10-04 22:27:40 +00:00
Michael Pratt 7ee4c16654 Revert "runtime: add padding to Linux kernel structures"
This reverts commit f0db7eae74.

Reason for revert: Breaks linux-386 tests

Change-Id: Ia51fbf97460ab52920b67d6db6177ac2d6b0058e
Reviewed-on: https://go-review.googlesource.com/c/go/+/353432
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>
2021-10-04 22:08:53 +00:00
Rhys Hiltner f0db7eae74 runtime: add padding to Linux kernel structures
Go exchanges siginfo and sigevent structures with the kernel. They
contain unions, but Go's use is limited to the first few fields. Pad out
the rest so the size Go sees is the same as what the Linux kernel sees.

This is a follow-up to CL 342052 which added the sigevent struct without
padding. It updates the siginfo struct as well so there are no bad
examples in the defs_linux_*.go files.

Change-Id: Id991d4a57826677dd7e6cc30ad113fa3b321cddf
Reviewed-on: https://go-review.googlesource.com/c/go/+/353136
Run-TryBot: Rhys Hiltner <rhys@justin.tv>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>
Trust: Michael Knyszek <mknyszek@google.com>
2021-10-04 21:10:16 +00:00
Changkun Ou 205640ed7b runtime: avoid run TestSyscallN in parallel
Fixes #48012

Change-Id: Ie27eb864ac387ecf5155a3aefa81661f1448ace5
Reviewed-on: https://go-review.googlesource.com/c/go/+/345670
Trust: Bryan C. Mills <bcmills@google.com>
Trust: Heschi Kreinick <heschi@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2021-09-30 18:10:18 +00:00
Josh Bleecher Snyder d3ad216f8e cmd/link, runtime: use offset for _func.entry
The first field of the func data stored by the linker is the
entry PC for the function. Prior to this change, this was stored
as a relocation to the function. Change this to be an offset
relative to runtime.text.

This reduces the number of relocations on darwin/arm64 by about 10%.
It also slightly shrinks binaries:

file      before    after     Δ       %
addr2line 3803058   3791298   -11760  -0.309%
api       5140114   5104242   -35872  -0.698%
asm       4886850   4840626   -46224  -0.946%
buildid   2512466   2503042   -9424   -0.375%
cgo       4374770   4342274   -32496  -0.743%
compile   22920530  22769202  -151328 -0.660%
cover     4624626   4588242   -36384  -0.787%
dist      3217570   3205522   -12048  -0.374%
doc       3715026   3684498   -30528  -0.822%
fix       3148226   3119266   -28960  -0.920%
link      6350226   6313362   -36864  -0.581%
nm        3768850   3757106   -11744  -0.312%
objdump   4140594   4127618   -12976  -0.313%
pack      2227474   2218818   -8656   -0.389%
pprof     13598706  13506786  -91920  -0.676%
test2json 2497234   2487426   -9808   -0.393%
trace     10198066  10118498  -79568  -0.780%
vet       6930658   6889074   -41584  -0.600%
total     108055044 107366900 -688144 -0.637%

It should also incrementally speed up binary launching.

This is the first step towards removing enough relocations
that pages that were previously dirtied by the loader may remain clean,
which will offer memory savings useful in constrained environments.

Change-Id: Icfba55e696ba2f9c99c4f179125ba5a3ba4369c9
Reviewed-on: https://go-review.googlesource.com/c/go/+/351463
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-09-29 22:14:22 +00:00