| // Copyright 2019 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 runtime |
| |
| import "unsafe" |
| |
| func lwp_mcontext_init(mc *mcontextt, stk unsafe.Pointer, mp *m, gp *g, fn uintptr) { |
| // Machine dependent mcontext initialisation for LWP. |
| mc.__gregs[_REG_ELR] = uint64(funcPC(lwp_tramp)) |
| mc.__gregs[_REG_X31] = uint64(uintptr(stk)) |
| mc.__gregs[_REG_X0] = uint64(uintptr(unsafe.Pointer(mp))) |
| mc.__gregs[_REG_X1] = uint64(uintptr(unsafe.Pointer(mp.g0))) |
| mc.__gregs[_REG_X2] = uint64(fn) |
| } |
| |
| //go:nosplit |
| func cputicks() int64 { |
| // Currently cputicks() is used in blocking profiler and to seed runtime·fastrand(). |
| // runtime·nanotime() is a poor approximation of CPU ticks that is enough for the profiler. |
| // TODO: need more entropy to better seed fastrand. |
| return nanotime() |
| } |