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authorStefan Majewsky <majewsky@gmx.net>2026-06-09 21:09:39 +0200
committerStefan Majewsky <majewsky@gmx.net>2026-06-09 21:09:39 +0200
commit6903a774ecbbd05596adda5e2b5e18d58dd3a8f9 (patch)
treef5d48f52f0da3da8d829436519bc66652bf41c64 /vendor/golang.org/x/sys/unix/affinity_linux.go
parente75d9e371269a4e46bffa6b3dd1fc7d040e82750 (diff)
downloadgofu-6903a774ecbbd05596adda5e2b5e18d58dd3a8f9.tar.gz
bump all dependencies to their latest versions
Diffstat (limited to 'vendor/golang.org/x/sys/unix/affinity_linux.go')
-rw-r--r--vendor/golang.org/x/sys/unix/affinity_linux.go131
1 files changed, 118 insertions, 13 deletions
diff --git a/vendor/golang.org/x/sys/unix/affinity_linux.go b/vendor/golang.org/x/sys/unix/affinity_linux.go
index 3c7a6d6..acd6257 100644
--- a/vendor/golang.org/x/sys/unix/affinity_linux.go
+++ b/vendor/golang.org/x/sys/unix/affinity_linux.go
@@ -13,11 +13,19 @@ import (
const cpuSetSize = _CPU_SETSIZE / _NCPUBITS
-// CPUSet represents a CPU affinity mask.
+// CPUSet represents a bit mask of CPUs, to be used with [SchedGetaffinity], [SchedSetaffinity],
+// and [SetMemPolicy].
+//
+// Note this type can only represent CPU IDs 0 through 1023.
+// Use [CPUSetDynamic]/[NewCPUSet] instead to avoid this limit.
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)))
+// CPUSetDynamic represents a bit mask of CPUs, to be used with [SchedGetaffinityDynamic],
+// [SchedSetaffinityDynamic], and [SetMemPolicyDynamic]. Use [NewCPUSet] to allocate.
+type CPUSetDynamic []cpuMask
+
+func schedAffinity(trap uintptr, pid int, size uintptr, ptr unsafe.Pointer) error {
+ _, _, e := RawSyscall(trap, uintptr(pid), uintptr(size), uintptr(ptr))
if e != 0 {
return errnoErr(e)
}
@@ -27,13 +35,13 @@ func schedAffinity(trap uintptr, pid int, set *CPUSet) error {
// 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)
+ return schedAffinity(SYS_SCHED_GETAFFINITY, pid, unsafe.Sizeof(*set), unsafe.Pointer(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)
+ return schedAffinity(SYS_SCHED_SETAFFINITY, pid, unsafe.Sizeof(*set), unsafe.Pointer(set))
}
// Zero clears the set s, so that it contains no CPUs.
@@ -41,6 +49,13 @@ func (s *CPUSet) Zero() {
clear(s[:])
}
+// Fill adds all possible CPU bits to the set s. On Linux, [SchedSetaffinity]
+// will silently ignore any invalid CPU bits in [CPUSet] so this is an
+// efficient way of resetting the CPU affinity of a process.
+func (s *CPUSet) Fill() {
+ cpuMaskFill(s[:])
+}
+
func cpuBitsIndex(cpu int) int {
return cpu / _NCPUBITS
}
@@ -49,24 +64,27 @@ func cpuBitsMask(cpu int) cpuMask {
return cpuMask(1 << (uint(cpu) % _NCPUBITS))
}
-// Set adds cpu to the set s.
-func (s *CPUSet) Set(cpu int) {
+func cpuMaskFill(s []cpuMask) {
+ for i := range s {
+ s[i] = ^cpuMask(0)
+ }
+}
+
+func cpuMaskSet(s []cpuMask, 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) {
+func cpuMaskClear(s []cpuMask, 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 {
+func cpuMaskIsSet(s []cpuMask, cpu int) bool {
i := cpuBitsIndex(cpu)
if i < len(s) {
return s[i]&cpuBitsMask(cpu) != 0
@@ -74,11 +92,98 @@ func (s *CPUSet) IsSet(cpu int) bool {
return false
}
-// Count returns the number of CPUs in the set s.
-func (s *CPUSet) Count() int {
+func cpuMaskCount(s []cpuMask) int {
c := 0
for _, b := range s {
c += bits.OnesCount64(uint64(b))
}
return c
}
+
+// Set adds cpu to the set s. If cpu is out of bounds for s, no action is taken.
+func (s *CPUSet) Set(cpu int) {
+ cpuMaskSet(s[:], cpu)
+}
+
+// Clear removes cpu from the set s. If cpu is out of bounds for s, no action is taken.
+func (s *CPUSet) Clear(cpu int) {
+ cpuMaskClear(s[:], cpu)
+}
+
+// IsSet reports whether cpu is in the set s.
+func (s *CPUSet) IsSet(cpu int) bool {
+ return cpuMaskIsSet(s[:], cpu)
+}
+
+// Count returns the number of CPUs in the set s.
+func (s *CPUSet) Count() int {
+ return cpuMaskCount(s[:])
+}
+
+// NewCPUSet creates a CPU affinity mask capable of representing CPU IDs
+// up to maxCPU (exclusive).
+func NewCPUSet(maxCPU int) CPUSetDynamic {
+ numMasks := (maxCPU + _NCPUBITS - 1) / _NCPUBITS
+ if numMasks == 0 {
+ numMasks = 1
+ }
+ return make(CPUSetDynamic, numMasks)
+}
+
+// Zero clears the set s, so that it contains no CPUs.
+func (s CPUSetDynamic) Zero() {
+ clear(s)
+}
+
+// Fill adds all possible CPU bits to the set s. On Linux, [SchedSetaffinityDynamic]
+// will silently ignore any invalid CPU bits in [CPUSetDynamic] so this is an
+// efficient way of resetting the CPU affinity of a process.
+func (s CPUSetDynamic) Fill() {
+ cpuMaskFill(s)
+}
+
+// Set adds cpu to the set s. If cpu is out of bounds for s, no action is taken.
+func (s CPUSetDynamic) Set(cpu int) {
+ cpuMaskSet(s, cpu)
+}
+
+// Clear removes cpu from the set s. If cpu is out of bounds for s, no action is taken.
+func (s CPUSetDynamic) Clear(cpu int) {
+ cpuMaskClear(s, cpu)
+}
+
+// IsSet reports whether cpu is in the set s.
+func (s CPUSetDynamic) IsSet(cpu int) bool {
+ return cpuMaskIsSet(s, cpu)
+}
+
+// Count returns the number of CPUs in the set s.
+func (s CPUSetDynamic) Count() int {
+ return cpuMaskCount(s)
+}
+
+func (s CPUSetDynamic) size() uintptr {
+ return uintptr(len(s)) * unsafe.Sizeof(cpuMask(0))
+}
+
+func (s CPUSetDynamic) pointer() unsafe.Pointer {
+ if len(s) == 0 {
+ return nil
+ }
+ return unsafe.Pointer(&s[0])
+}
+
+// SchedGetaffinityDynamic gets the CPU affinity mask of the thread specified by pid.
+// If pid is 0 the calling thread is used.
+//
+// If the set is smaller than the size of the affinity mask used by the kernel,
+// [EINVAL] is returned.
+func SchedGetaffinityDynamic(pid int, set CPUSetDynamic) error {
+ return schedAffinity(SYS_SCHED_GETAFFINITY, pid, set.size(), set.pointer())
+}
+
+// SchedSetaffinityDynamic sets the CPU affinity mask of the thread specified by pid.
+// If pid is 0 the calling thread is used.
+func SchedSetaffinityDynamic(pid int, set CPUSetDynamic) error {
+ return schedAffinity(SYS_SCHED_SETAFFINITY, pid, set.size(), set.pointer())
+}