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authorEmile <git@emile.space>2024-08-16 19:50:26 +0200
committerEmile <git@emile.space>2024-08-16 19:50:26 +0200
commit1a57267a17c2fc17fb6e104846fabc3e363c326c (patch)
tree1e574e3a80622086dc3c81ff9cba65ef7049b1a9 /vendor/golang.org/x/sys/unix/affinity_linux.go
initial commit
Diffstat (limited to 'vendor/golang.org/x/sys/unix/affinity_linux.go')
-rw-r--r--vendor/golang.org/x/sys/unix/affinity_linux.go86
1 files changed, 86 insertions, 0 deletions
diff --git a/vendor/golang.org/x/sys/unix/affinity_linux.go b/vendor/golang.org/x/sys/unix/affinity_linux.go
new file mode 100644
index 0000000..6e5c81a
--- /dev/null
+++ b/vendor/golang.org/x/sys/unix/affinity_linux.go
@@ -0,0 +1,86 @@
+// Copyright 2018 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.
+
+// CPU affinity functions
+
+package unix
+
+import (
+	"math/bits"
+	"unsafe"
+)
+
+const cpuSetSize = _CPU_SETSIZE / _NCPUBITS
+
+// CPUSet represents a CPU affinity mask.
+type CPUSet [cpuSetSize]cpuMask
+
+func schedAffinity(trap uintptr, pid int, set *CPUSet) error {
+	_, _, e := RawSyscall(trap, uintptr(pid), uintptr(unsafe.Sizeof(*set)), uintptr(unsafe.Pointer(set)))
+	if e != 0 {
+		return errnoErr(e)
+	}
+	return nil
+}
+
+// SchedGetaffinity gets the CPU affinity mask of the thread specified by pid.
+// If pid is 0 the calling thread is used.
+func SchedGetaffinity(pid int, set *CPUSet) error {
+	return schedAffinity(SYS_SCHED_GETAFFINITY, pid, set)
+}
+
+// SchedSetaffinity sets the CPU affinity mask of the thread specified by pid.
+// If pid is 0 the calling thread is used.
+func SchedSetaffinity(pid int, set *CPUSet) error {
+	return schedAffinity(SYS_SCHED_SETAFFINITY, pid, set)
+}
+
+// Zero clears the set s, so that it contains no CPUs.
+func (s *CPUSet) Zero() {
+	for i := range s {
+		s[i] = 0
+	}
+}
+
+func cpuBitsIndex(cpu int) int {
+	return cpu / _NCPUBITS
+}
+
+func cpuBitsMask(cpu int) cpuMask {
+	return cpuMask(1 << (uint(cpu) % _NCPUBITS))
+}
+
+// Set adds cpu to the set s.
+func (s *CPUSet) Set(cpu int) {
+	i := cpuBitsIndex(cpu)
+	if i < len(s) {
+		s[i] |= cpuBitsMask(cpu)
+	}
+}
+
+// Clear removes cpu from the set s.
+func (s *CPUSet) Clear(cpu int) {
+	i := cpuBitsIndex(cpu)
+	if i < len(s) {
+		s[i] &^= cpuBitsMask(cpu)
+	}
+}
+
+// IsSet reports whether cpu is in the set s.
+func (s *CPUSet) IsSet(cpu int) bool {
+	i := cpuBitsIndex(cpu)
+	if i < len(s) {
+		return s[i]&cpuBitsMask(cpu) != 0
+	}
+	return false
+}
+
+// Count returns the number of CPUs in the set s.
+func (s *CPUSet) Count() int {
+	c := 0
+	for _, b := range s {
+		c += bits.OnesCount64(uint64(b))
+	}
+	return c
+}