Struct ProcessorSet 

pub struct ProcessorSet { /* private fields */ }

A set of logical processors, correctly spanning more than one processor group.

A Windows thread’s affinity is a GROUP_AFFINITY – one group and a bitmask within it – because a group is a hard boundary: no single mask can name processors in two different groups. A type that silently flattened to one 64-bit mask would misrepresent any topology wider than one group, which is exactly the class of bug this type exists to prevent. ProcessorSet keeps each group’s mask separate instead.

Implementations

impl ProcessorSet

pub fn empty() -> Self

A set naming no processors.

pub fn from_group_mask(group: u16, mask: usize) -> Self

A set naming every bit set in mask within group.

pub fn can_represent(number: u8) -> bool

Whether a processor number fits this platform’s group width.

A ProcessorSet holds one bit per processor in a usize, so the ceiling is usize::BITS – 64 on x86-64, 32 on i686-pc-windows-msvc. ProcessorId::number is a u8 and its field is public, so a caller can build an id this set cannot hold; Self::insert asserts on one, and this is how a caller asks before rather than being aborted.

pub fn insert(&mut self, group: u16, number: u8)

Add number within group to the set.

Panics

Panics if number is MAX_PROCESSORS_PER_GROUP or greater: a processor group cannot hold more processors than a mask has bits. Self::can_represent is how a caller holding a publicly-constructed crate::ProcessorId asks first – the panic is for a caller building a set it controls, not a way to reject a query’s argument.

pub fn is_empty(&self) -> bool

Whether the set names no processors.

pub fn len(&self) -> usize

How many processors the set names, across every group.

pub fn contains(&self, group: u16, number: u8) -> bool

Whether group/number is a member of this set.

pub fn group_mask(&self, group: u16) -> usize

The raw mask for a single group, or 0 if the group has no members here.

pub fn group_masks(&self) -> impl Iterator<Item = (u16, usize)> + '_

Iterate over (group, mask) pairs, one per group with any member here, in ascending group order.

pub fn iter(&self) -> impl Iterator<Item = (u16, u8)> + '_

Iterate over every (group, number) member, in ascending order.

pub fn intersection(&self, other: &Self) -> Self

The set of processors present in both self and other.

pub fn union(&self, other: &Self) -> Self

The set of processors present in either self or other.

pub fn is_disjoint(&self, other: &Self) -> bool

Whether self and other share no processors.

pub fn is_subset(&self, other: &Self) -> bool

Whether every processor in self is also in other.

This is the comparison the granularity order is built on (M2+.2): inclusion is checkable against the memberships the platform actually reported, where a firmware level number is only asserted. The empty set is a subset of everything, which follows from the definition and is not a special case.

Trait Implementations

impl Clone for ProcessorSet

fn clone(&self) -> ProcessorSet

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ProcessorSet

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ProcessorSet

fn default() -> ProcessorSet

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for ProcessorSet

Available on crate feature serde only.

fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error>

Deserialize this value from the given Serde deserializer.

impl Eq for ProcessorSet

impl FromIterator<(u16, u8)> for ProcessorSet

fn from_iter<T: IntoIterator<Item = (u16, u8)>>(iter: T) -> Self

Creates a value from an iterator.

impl PartialEq for ProcessorSet

fn eq(&self, other: &ProcessorSet) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for ProcessorSet

Available on crate feature serde only.

fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error>

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for ProcessorSet