Files
golang.go/src/sync/runtime.go
Carlo Alberto Ferraris 41cb0aedff sync: allow inlining the Mutex.Lock fast path
name                    old time/op  new time/op  delta
MutexUncontended        18.9ns ± 0%  16.2ns ± 0%  -14.29%  (p=0.000 n=19+19)
MutexUncontended-4      4.75ns ± 1%  4.08ns ± 0%  -14.20%  (p=0.000 n=20+19)
MutexUncontended-16     2.05ns ± 0%  2.11ns ± 0%   +2.93%  (p=0.000 n=19+16)
Mutex                   19.3ns ± 1%  16.2ns ± 0%  -15.86%  (p=0.000 n=17+19)
Mutex-4                 52.4ns ± 4%  48.6ns ± 9%   -7.22%  (p=0.000 n=20+20)
Mutex-16                 139ns ± 2%   140ns ± 3%   +1.03%  (p=0.011 n=16+20)
MutexSlack              18.9ns ± 1%  16.2ns ± 1%  -13.96%  (p=0.000 n=20+20)
MutexSlack-4             225ns ± 8%   211ns ±10%   -5.94%  (p=0.000 n=18+19)
MutexSlack-16           98.4ns ± 1%  90.9ns ± 1%   -7.60%  (p=0.000 n=17+18)
MutexWork               58.2ns ± 3%  55.4ns ± 0%   -4.82%  (p=0.000 n=20+17)
MutexWork-4              103ns ± 7%    95ns ±18%   -8.03%  (p=0.000 n=20+20)
MutexWork-16             163ns ± 2%   155ns ± 2%   -4.47%  (p=0.000 n=18+18)
MutexWorkSlack          57.7ns ± 1%  55.4ns ± 0%   -3.99%  (p=0.000 n=20+13)
MutexWorkSlack-4         276ns ±13%   260ns ±10%   -5.64%  (p=0.001 n=19+19)
MutexWorkSlack-16        147ns ± 0%   156ns ± 1%   +5.87%  (p=0.000 n=14+19)
MutexNoSpin              968ns ± 0%   900ns ± 1%   -6.98%  (p=0.000 n=20+18)
MutexNoSpin-4            270ns ± 2%   255ns ± 2%   -5.74%  (p=0.000 n=19+20)
MutexNoSpin-16           120ns ± 4%   112ns ± 0%   -6.99%  (p=0.000 n=19+14)
MutexSpin               3.13µs ± 1%  3.19µs ± 6%     ~     (p=0.401 n=20+20)
MutexSpin-4              832ns ± 2%   831ns ± 1%   -0.17%  (p=0.023 n=16+18)
MutexSpin-16             395ns ± 0%   399ns ± 0%   +0.94%  (p=0.000 n=17+19)
RWMutexUncontended      69.5ns ± 0%  68.4ns ± 0%   -1.59%  (p=0.000 n=20+20)
RWMutexUncontended-4    17.5ns ± 0%  16.7ns ± 0%   -4.30%  (p=0.000 n=18+17)
RWMutexUncontended-16   7.92ns ± 0%  7.87ns ± 0%   -0.61%  (p=0.000 n=18+17)
RWMutexWrite100         24.9ns ± 1%  25.0ns ± 1%   +0.32%  (p=0.000 n=20+20)
RWMutexWrite100-4       46.2ns ± 4%  46.2ns ± 5%     ~     (p=0.840 n=19+20)
RWMutexWrite100-16      69.9ns ± 5%  69.9ns ± 3%     ~     (p=0.545 n=20+19)
RWMutexWrite10          27.0ns ± 2%  26.8ns ± 2%   -0.98%  (p=0.001 n=20+20)
RWMutexWrite10-4        34.7ns ± 2%  35.0ns ± 4%     ~     (p=0.191 n=18+20)
RWMutexWrite10-16       37.2ns ± 4%  37.3ns ± 2%     ~     (p=0.438 n=20+19)
RWMutexWorkWrite100      164ns ± 0%   163ns ± 0%   -0.24%  (p=0.025 n=20+20)
RWMutexWorkWrite100-4    193ns ± 3%   191ns ± 2%   -1.06%  (p=0.027 n=20+20)
RWMutexWorkWrite100-16   210ns ± 3%   207ns ± 3%   -1.22%  (p=0.038 n=20+20)
RWMutexWorkWrite10       153ns ± 0%   153ns ± 0%     ~     (all equal)
RWMutexWorkWrite10-4     178ns ± 2%   179ns ± 2%     ~     (p=0.186 n=20+20)
RWMutexWorkWrite10-16    192ns ± 2%   192ns ± 2%     ~     (p=0.731 n=19+20)

linux/amd64 bin/go 14663387 (previous commit 14630572, +32815/+0.22%)

Change-Id: I98171006dce14069b1a62da07c3d165455a7906b
Reviewed-on: https://go-review.googlesource.com/c/go/+/148959
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-09 05:08:04 +00:00

68 lines
2.2 KiB
Go

// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package sync
import "unsafe"
// defined in package runtime
// Semacquire waits until *s > 0 and then atomically decrements it.
// It is intended as a simple sleep primitive for use by the synchronization
// library and should not be used directly.
func runtime_Semacquire(s *uint32)
// SemacquireMutex is like Semacquire, but for profiling contended Mutexes.
// If lifo is true, queue waiter at the head of wait queue.
// skipframes is the number of frames to omit during tracing, counting from
// runtime_SemacquireMutex's caller.
func runtime_SemacquireMutex(s *uint32, lifo bool, skipframes int)
// Semrelease atomically increments *s and notifies a waiting goroutine
// if one is blocked in Semacquire.
// It is intended as a simple wakeup primitive for use by the synchronization
// library and should not be used directly.
// If handoff is true, pass count directly to the first waiter.
// skipframes is the number of frames to omit during tracing, counting from
// runtime_Semrelease's caller.
func runtime_Semrelease(s *uint32, handoff bool, skipframes int)
// Approximation of notifyList in runtime/sema.go. Size and alignment must
// agree.
type notifyList struct {
wait uint32
notify uint32
lock uintptr
head unsafe.Pointer
tail unsafe.Pointer
}
// See runtime/sema.go for documentation.
func runtime_notifyListAdd(l *notifyList) uint32
// See runtime/sema.go for documentation.
func runtime_notifyListWait(l *notifyList, t uint32)
// See runtime/sema.go for documentation.
func runtime_notifyListNotifyAll(l *notifyList)
// See runtime/sema.go for documentation.
func runtime_notifyListNotifyOne(l *notifyList)
// Ensure that sync and runtime agree on size of notifyList.
func runtime_notifyListCheck(size uintptr)
func init() {
var n notifyList
runtime_notifyListCheck(unsafe.Sizeof(n))
}
// Active spinning runtime support.
// runtime_canSpin reports whether spinning makes sense at the moment.
func runtime_canSpin(i int) bool
// runtime_doSpin does active spinning.
func runtime_doSpin()
func runtime_nanotime() int64