Commit Graph

19 Commits

Author SHA1 Message Date
Xiaodong Liu 8542bd8938 runtime: support vdso for linux/loong64
Contributors to the loong64 port are:
  Weining Lu <luweining@loongson.cn>
  Lei Wang <wanglei@loongson.cn>
  Lingqin Gong <gonglingqin@loongson.cn>
  Xiaolin Zhao <zhaoxiaolin@loongson.cn>
  Meidan Li <limeidan@loongson.cn>
  Xiaojuan Zhai <zhaixiaojuan@loongson.cn>
  Qiyuan Pu <puqiyuan@loongson.cn>
  Guoqi Chen <chenguoqi@loongson.cn>

This port has been updated to Go 1.15.6:
  https://github.com/loongson/go

Updates #46229

Change-Id: Ie9bb5ccfc28e65036e2088c232bb333dcb259a60
Reviewed-on: https://go-review.googlesource.com/c/go/+/368076
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
2022-05-19 19:32:35 +00:00
Axel Busch 636c5f0208 runtime: enable vDSO support for s390x architecture
This change adds support for vDSO for s390x architecture. This avoids the use of system calls in nanotime and walltime and accelerates them by factor 4-5.

Benchmarks:
100,000,000 x time.Now():
syscall fallback	13923ms		139.23 ns/op
vDSO enabled		2640ms	 	26.40 ns/op

Change-Id: Ic679fe31048379e59ccf83b400140f13c9d49696
GitHub-Last-Rev: 8f6e918a45
GitHub-Pull-Request: golang/go#49717
Reviewed-on: https://go-review.googlesource.com/c/go/+/365995
Run-TryBot: Paul Murphy <murp@ibm.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Paul Murphy <murp@ibm.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Jonathan Albrecht <jonathan.albrecht@ibm.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Bill O'Farrell <billotosyr@gmail.com>
2022-05-11 13:30:43 +00:00
Russ Cox 9839668b56 all: separate doc comment from //go: directives
A future change to gofmt will rewrite

	// Doc comment.
	//go:foo

to

	// Doc comment.
	//
	//go:foo

Apply that change preemptively to all comments (not necessarily just doc comments).

For #51082.

Change-Id: Iffe0285418d1e79d34526af3520b415a12203ca9
Reviewed-on: https://go-review.googlesource.com/c/go/+/384260
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
2022-04-05 17:54:15 +00:00
Russ Cox f229e7031a all: go fix -fix=buildtag std cmd (except for bootstrap deps, vendor)
When these packages are released as part of Go 1.18,
Go 1.16 will no longer be supported, so we can remove
the +build tags in these files.

Ran go fix -fix=buildtag std cmd and then reverted the bootstrapDirs
as defined in src/cmd/dist/buildtool.go, which need to continue
to build with Go 1.4 for now.

Also reverted src/vendor and src/cmd/vendor, which will need
to be updated in their own repos first.

Manual changes in runtime/pprof/mprof_test.go to adjust line numbers.

For #41184.

Change-Id: Ic0f93f7091295b6abc76ed5cd6e6746e1280861e
Reviewed-on: https://go-review.googlesource.com/c/go/+/344955
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2021-10-28 18:17:57 +00:00
Meng Zhuo 1bd35fab05 runtime: use vDSO clock_gettime on linux/riscv64
Speed up nanotime1 and walltime on riscv64 with vDSO, just like the
other vDSO-enabled targets.

name          old time/op  new time/op  delta
Now           1.53µs ± 1%  1.05µs ± 3%  -31.74%  (p=0.000 n=10+10)
NowUnixNano   1.54µs ± 0%  1.05µs ± 2%  -31.91%  (p=0.000 n=9+10)
NowUnixMilli  1.56µs ± 1%  1.06µs ± 1%  -31.73%  (p=0.000 n=10+10)
NowUnixMicro  1.56µs ± 1%  1.05µs ± 1%  -32.80%  (p=0.000 n=9+10)

Change-Id: I69b3fe3cc57685a826c53b366c0992e8048399bb
Reviewed-on: https://go-review.googlesource.com/c/go/+/328509
Trust: Meng Zhuo <mzh@golangcn.org>
Run-TryBot: Meng Zhuo <mzh@golangcn.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-09-02 01:23:38 +00:00
Russ Cox d4b2638234 all: go fmt std cmd (but revert vendor)
Make all our package sources use Go 1.17 gofmt format
(adding //go:build lines).

Part of //go:build change (#41184).
See https://golang.org/design/draft-gobuild

Change-Id: Ia0534360e4957e58cd9a18429c39d0e32a6addb4
Reviewed-on: https://go-review.googlesource.com/c/go/+/294430
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2021-02-20 03:54:50 +00:00
Wang Xuerui 210e3677f9 runtime: use vDSO clock_gettime on linux/mips64x
Speed up nanotime1 and walltime1 on MIPS64 with vDSO, just like the
other vDSO-enabled targets.

Benchmark numbers on Loongson 3A3000 (GOARCH=mips64le, 1.4GHz) against
current master:

benchmark                old ns/op     new ns/op     delta
BenchmarkNow             868           293           -66.24%
BenchmarkNowUnixNano     851           296           -65.22%

Performance hit on fallback case, tested by using a wrong vDSO symbol name:

benchmark                old ns/op     new ns/op     delta
BenchmarkNow             868           889           +2.42%
BenchmarkNowUnixNano     851           893           +4.94%

Change-Id: Ibfb48893cd060536359863ffee7624c00def646b
GitHub-Last-Rev: 03a58ac2e4
GitHub-Pull-Request: golang/go#35181
Reviewed-on: https://go-review.googlesource.com/c/go/+/203578
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2019-11-04 18:53:43 +00:00
Yuichi Nishiwaki 904f046e2b runtime: fix crash during VDSO calls on arm
As discussed in #32912, a crash occurs when go runtime calls a VDSO function (say
__vdso_clock_gettime) and a signal arrives to that thread.
Since VDSO functions temporarily destroy the G register (R10),
Go functions asynchronously executed in that thread (i.e. Go's signal
handler) can try to load data from the destroyed G, which causes
segmentation fault.

To fix the issue a guard is inserted in front of sigtrampgo, so that the control escapes from
signal handlers without touching G in case the signal occurred in the VDSO context.
The test case included in the patch is take from discussion in a relevant thread on github:
https://github.com/golang/go/issues/32912#issuecomment-517874531.
This patch not only fixes the issue on AArch64 but also that on 32bit ARM.

Fixes #32912

Change-Id: I657472e54b7aa3c617fabc5019ce63aa4105624a
GitHub-Last-Rev: 28ce42c4a0
GitHub-Pull-Request: golang/go#34030
Reviewed-on: https://go-review.googlesource.com/c/go/+/192937
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-09-11 03:32:35 +00:00
Tobias Klauser 9e277f7d55 all: use "reports whether" consistently instead of "returns whether"
Follow-up for CL 147037 and after Brad noticed the "returns whether"
pattern during the review of CL 150621.

Go documentation style for boolean funcs is to say:

    // Foo reports whether ...
    func Foo() bool

(rather than "returns whether")

Created with:

    $ perl -i -npe 's/returns whether/reports whether/' $(git grep -l "returns whether" | grep -v vendor)

Change-Id: I15fe9ff99180ad97750cd05a10eceafdb12dc0b4
Reviewed-on: https://go-review.googlesource.com/c/150918
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-12-02 15:12:26 +00:00
Carlos Eduardo Seo dbd8af7472 runtime: add support for VDSO on ppc64x for use in walltime/nanotime
This change adds support for VDSO on ppc64x, making it possible to
avoid a syscall in walltime and nanotime.

BenchmarkClockVDSOAndFallbackPaths/vDSO-192             20000000    66.0 ns/op
BenchmarkClockVDSOAndFallbackPaths/Fallback-192          1000000    1456 ns/op

Change-Id: I3373bd804b6f122961de3ae9d034e6ccf35748e6
Reviewed-on: https://go-review.googlesource.com/131135
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
2018-08-31 13:12:31 +00:00
Tim Cooper 161874da2a all: update comment URLs from HTTP to HTTPS, where possible
Each URL was manually verified to ensure it did not serve up incorrect
content.

Change-Id: I4dc846227af95a73ee9a3074d0c379ff0fa955df
Reviewed-on: https://go-review.googlesource.com/115798
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2018-06-01 21:52:00 +00:00
Meng Zhuo ea59ebd338 runtime: use vDSO for clock_gettime on linux/arm64
Use the __vdso_clock_gettime fast path via the vDSO on linux/arm64 to
speed up nanotime and walltime. This results in the following
performance improvement for time.Now on Cavium ThunderX:

name     old time/op  new time/op  delta
TimeNow   442ns ± 0%   163ns ± 0%  -63.16%  (p=0.000 n=10+10)

And benchmarks on VDSO

BenchmarkClockVDSOAndFallbackPaths/vDSO         10000000 166 ns/op
BenchmarkClockVDSOAndFallbackPaths/Fallback     3000000 456 ns/op

Change-Id: I326118c6dff865eaa0569fc45d1fc1ff95cb74f6
Reviewed-on: https://go-review.googlesource.com/99855
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-03-27 13:21:27 +00:00
Ian Lance Taylor 419c06455a runtime: get traceback from VDSO code
Currently if a profiling signal arrives while executing within a VDSO
the profiler will report _ExternalCode, which is needlessly confusing
for a pure Go program. Change the VDSO calling code to record the
caller's PC/SP, so that we can do a traceback from that point. If that
fails for some reason, report _VDSO rather than _ExternalCode, which
should at least point in the right direction.

This adds some instructions to the code that calls the VDSO, but the
slowdown is reasonably negligible:

name                                  old time/op  new time/op  delta
ClockVDSOAndFallbackPaths/vDSO-8      40.5ns ± 2%  41.3ns ± 1%  +1.85%  (p=0.002 n=10+10)
ClockVDSOAndFallbackPaths/Fallback-8  41.9ns ± 1%  43.5ns ± 1%  +3.84%  (p=0.000 n=9+9)
TimeNow-8                             41.5ns ± 3%  41.5ns ± 2%    ~     (p=0.723 n=10+10)

Fixes #24142

Change-Id: Iacd935db3c4c782150b3809aaa675a71799b1c9c
Reviewed-on: https://go-review.googlesource.com/97315
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2018-03-07 23:35:25 +00:00
Ian Lance Taylor 7178267b59 runtime: rename vdso symbols to use camel case
This was originally C code using names with underscores, which were
retained when the code was rewritten into Go. Change the code to use
Go-like camel case names.

The names that come from the ELF ABI are left unchanged.

Change-Id: I181bc5dd81284c07bc67b7df4635f4734b41d646
Reviewed-on: https://go-review.googlesource.com/98520
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-03-05 19:12:32 +00:00
Tobias Klauser 51b027116c runtime: use vDSO for clock_gettime on linux/arm
Use the __vdso_clock_gettime fast path via the vDSO on linux/arm to
speed up nanotime and walltime. This results in the following
performance improvement for time.Now on a RaspberryPi 3 (running
32bit Raspbian, i.e. GOOS=linux/GOARCH=arm):

name     old time/op  new time/op  delta
TimeNow  0.99µs ± 0%  0.39µs ± 1%  -60.74%  (p=0.000 n=12+20)

Change-Id: I3598278a6c88d7f6a6ce66c56b9d25f9dd2f4c9a
Reviewed-on: https://go-review.googlesource.com/98095
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-03-03 12:12:58 +00:00
Tobias Klauser 7e054553ad runtime: update URL of the Linux vDSO parser tool
The tool was moved to tools/Testing/selftests within the Linux kernel
source tree. Adjust the URL in the comments of vdso_linux.go

Change-Id: I86b9cae4b898c4a45bc7c54891ce6ead91a22670
Reviewed-on: https://go-review.googlesource.com/87815
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-01-16 15:11:05 +00:00
Frank Somers af40cbe83c runtime: use vDSO on linux/386 to improve time.Now performance
This change adds support for accelerating time.Now by using
the __vdso_clock_gettime fast-path via the vDSO on linux/386
if it is available.

When the vDSO path to the clocks is available, it is typically
5x-10x faster than the syscall path (see benchmark extract
below).  Two such calls are made for each time.Now() call
on most platforms as of go 1.9.

- Add vdso_linux_386.go, containing the ELF32 definitions
  for use by vdso_linux.go, the maximum array size, and
  the symbols to be located in the vDSO.

- Modify runtime.walltime and runtime.nanotime to check for
  and use the vDSO fast-path if available, or fall back to
  the existing syscall path.

- Reduce the stack reservations for runtime.walltime and
  runtime.monotime from 32 to 16 bytes. It appears the syscall
  path actually only needed 8 bytes, but 16 is now needed to
  cover the syscall and vDSO paths.

- Remove clearing DX from the syscall paths as clock_gettime
  only takes 2 args (BX, CX in syscall calling convention),
  so there should be no need to clear DX.

The included BenchmarkTimeNow was run with -cpu=1 -count=20
on an "Intel(R) Celeron(R) CPU J1900 @ 1.99GHz", comparing
released go 1.9.1 vs this change. This shows a gain in
performance on linux/386 (6.89x), and that no regression
occurred on linux/amd64 due to this change.

Kernel: linux/i686, GOOS=linux GOARCH=386
   name      old time/op  new time/op  delta
   TimeNow   978ns ± 0%   142ns ± 0%  -85.48%  (p=0.000 n=16+20)

Kernel: linux/x86_64, GOOS=linux GOARCH=amd64
   name      old time/op  new time/op  delta
   TimeNow   125ns ± 0%   125ns ± 0%   ~       (all equal)

Gains are more dramatic in virtualized environments,
presumably due to the overhead of virtualizing the syscall.

Fixes #22190

Change-Id: I2f83ce60cb1b8b310c9ced0706bb463c1b3aedf8
Reviewed-on: https://go-review.googlesource.com/69390
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 14:41:04 +00:00
Frank Somers c14dcfda6b runtime: factor amd64 specifics from vdso_linux.go
This is a preparation step for adding vDSO support on linux/386.

This change relocates the elf64 and amd64 specifics from
vdso_linux.go to a new vdso_linux_amd64.go.

This should enable vdso_linux.go to be used for vDSO
support on linux architectures other than amd64.

- Relocate the elf64X structure definitions appropriate to amd64,
  and change their names to elfX so that the code in vdso_linux.go
  is ELFnn-agnostic.

- Relocate the sym_keys and corresponding __vdso_* variables
  appropriate to amd64.

- Provide an amd64-specific constant for the maximum byte size of
  an array, and use this in vdso_linux.go to compute constants for
  sizing the elf structure arrays traversed in the loaded vDSO.

Change-Id: I1edb4e4ec9f2d79b7533aa95fbd09f771fa4edef
Reviewed-on: https://go-review.googlesource.com/69391
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 02:04:20 +00:00
Frank Somers 4477107b7b runtime: move vdso_linux_amd64.go to vdso_linux.go
This is a preparation step for adding vDSO support on linux/386.

In a follow-on change, the vDSO ELF symbol lookup code in this
file will be refactored so it can be used on multiple architectures.

First, move the file to an architecture-neutral file name so that
the change history is preserved. Build tags are added so that the
build behaves as it did before.

vdso_linux_amd64.go will be recreated later, just containing the
amd64 specifics.

If the move and refactor were combined in a single change, then the
history to date would be lost because git would see the existing code
as a new file.

Change-Id: Iddb5da0d7faf141fd7cc835fe6a80c80153897e9
Reviewed-on: https://go-review.googlesource.com/69710
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-11 13:42:27 +00:00