1 // Copyright 2009 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 package runtime 6 7 import ( 8 "runtime/internal/atomic" 9 _ "unsafe" // for go:linkname 10 ) 11 12 //go:generate go run wincallback.go 13 //go:generate go run mkduff.go 14 //go:generate go run mkfastlog2table.go 15 16 var ticks struct { 17 lock mutex 18 pad uint32 // ensure 8-byte alignment of val on 386 19 val uint64 20 } 21 22 // Note: Called by runtime/pprof in addition to runtime code. 23 func tickspersecond() int64 { 24 r := int64(atomic.Load64(&ticks.val)) 25 if r != 0 { 26 return r 27 } 28 lock(&ticks.lock) 29 r = int64(ticks.val) 30 if r == 0 { 31 t0 := nanotime() 32 c0 := cputicks() 33 usleep(100 * 1000) 34 t1 := nanotime() 35 c1 := cputicks() 36 if t1 == t0 { 37 t1++ 38 } 39 r = (c1 - c0) * 1000 * 1000 * 1000 / (t1 - t0) 40 if r == 0 { 41 r++ 42 } 43 atomic.Store64(&ticks.val, uint64(r)) 44 } 45 unlock(&ticks.lock) 46 return r 47 } 48 49 var envs []string 50 var argslice []string 51 52 //go:linkname syscall_runtime_envs syscall.runtime_envs 53 func syscall_runtime_envs() []string { return append([]string{}, envs...) } 54 55 //go:linkname syscall_Getpagesize syscall.Getpagesize 56 func syscall_Getpagesize() int { return int(physPageSize) } 57 58 //go:linkname os_runtime_args os.runtime_args 59 func os_runtime_args() []string { return append([]string{}, argslice...) } 60
