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| author | Paul E. Murphy <murp@ibm.com> | 2020-09-09 17:24:23 -0500 |
|---|---|---|
| committer | Lynn Boger <laboger@linux.vnet.ibm.com> | 2020-10-21 14:34:44 +0000 |
| commit | 15ead857dbc638b9d83a7686acf0dc746fc45918 (patch) | |
| tree | db6466a49022bd1c47f01f3d557bb85d63b45d7c /src/cmd/go/internal/load/pkg.go | |
| parent | 54c0237346adfc2cac7bbebba80d652227ab6ea5 (diff) | |
| download | go-15ead857dbc638b9d83a7686acf0dc746fc45918.tar.gz go-15ead857dbc638b9d83a7686acf0dc746fc45918.zip | |
cmd/compiler,cmd/go,sync: add internal {LoadAcq,StoreRel}64 on ppc64
Add an internal atomic intrinsic for load with acquire semantics
(extending LoadAcq to 64b) and add LoadAcquintptr for internal
use within the sync package. For other arches, this remaps to the
appropriate atomic.Load{,64} intrinsic which should not alter code
generation.
Similarly, add StoreRel{uintptr,64} for consistency, and inline.
Finally, add an exception to allow sync to directly use the
runtime/internal/atomic package which avoids more convoluted
workarounds (contributed by Lynn Boger).
In an extreme example, sync.(*Pool).pin consumes 20% of wall time
during fmt tests. This is reduced to 5% on ppc64le/power9.
From the fmt benchmarks on ppc64le:
name old time/op new time/op delta
SprintfPadding 468ns ± 0% 451ns ± 0% -3.63%
SprintfEmpty 73.3ns ± 0% 51.9ns ± 0% -29.20%
SprintfString 135ns ± 0% 122ns ± 0% -9.63%
SprintfTruncateString 232ns ± 0% 214ns ± 0% -7.76%
SprintfTruncateBytes 216ns ± 0% 202ns ± 0% -6.48%
SprintfSlowParsingPath 162ns ± 0% 142ns ± 0% -12.35%
SprintfQuoteString 1.00µs ± 0% 0.99µs ± 0% -1.39%
SprintfInt 117ns ± 0% 104ns ± 0% -11.11%
SprintfIntInt 190ns ± 0% 175ns ± 0% -7.89%
SprintfPrefixedInt 232ns ± 0% 212ns ± 0% -8.62%
SprintfFloat 270ns ± 0% 255ns ± 0% -5.56%
SprintfComplex 1.01µs ± 0% 0.99µs ± 0% -1.68%
SprintfBoolean 127ns ± 0% 111ns ± 0% -12.60%
SprintfHexString 220ns ± 0% 198ns ± 0% -10.00%
SprintfHexBytes 261ns ± 0% 252ns ± 0% -3.45%
SprintfBytes 600ns ± 0% 590ns ± 0% -1.67%
SprintfStringer 684ns ± 0% 658ns ± 0% -3.80%
SprintfStructure 2.57µs ± 0% 2.57µs ± 0% -0.12%
ManyArgs 669ns ± 0% 646ns ± 0% -3.44%
FprintInt 140ns ± 0% 136ns ± 0% -2.86%
FprintfBytes 184ns ± 0% 181ns ± 0% -1.63%
FprintIntNoAlloc 140ns ± 0% 136ns ± 0% -2.86%
ScanInts 929µs ± 0% 921µs ± 0% -0.79%
ScanRecursiveInt 122ms ± 0% 121ms ± 0% -0.11%
ScanRecursiveIntReaderWrapper 122ms ± 0% 122ms ± 0% -0.18%
Change-Id: I4d66780261b57b06ef600229e475462e7313f0d6
Reviewed-on: https://go-review.googlesource.com/c/go/+/253748
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Keith Randall <khr@golang.org>
Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Go Bot <gobot@golang.org>
Diffstat (limited to 'src/cmd/go/internal/load/pkg.go')
| -rw-r--r-- | src/cmd/go/internal/load/pkg.go | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/src/cmd/go/internal/load/pkg.go b/src/cmd/go/internal/load/pkg.go index 2bdc08ba36..c9665265e9 100644 --- a/src/cmd/go/internal/load/pkg.go +++ b/src/cmd/go/internal/load/pkg.go @@ -1337,6 +1337,11 @@ func disallowInternal(srcDir string, importer *Package, importerPath string, p * return p } + // Allow sync package to access lightweight atomic functions limited to the runtime. + if p.Standard && strings.HasPrefix(importerPath, "sync") && p.ImportPath == "runtime/internal/atomic" { + return p + } + // Internal is present. // Map import path back to directory corresponding to parent of internal. if i > 0 { |