lib::cpumask Class Reference

A fixed-capacity, SMP-aware set of CPU identifiers. More...

Public Member Functions
auto	any () const noexcept -> bool
	Returns true if the set is non-empty.
auto	clear (usize cpu, memory_order order=memory_order::seq_cst) noexcept -> void
	Atomically remove a CPU from the set.
auto	clear_relaxed (usize cpu) noexcept -> void
	Non-atomically remove a CPU (use only when externally serialized).
auto	count () const noexcept -> usize
	Number of CPUs currently in the set.
auto	first_set () const noexcept -> std::optional< usize >
	Index of the lowest-numbered member.
template<typename Fn>
auto	for_each (Fn &&fn, memory_order confirm=memory_order::acquire) const noexcept -> void
	Invoke fn for every member CPU, in ascending id order.
auto	next_set (usize after) const noexcept -> std::optional< usize >
	Index of the lowest-numbered member strictly after after.
auto	none () const noexcept -> bool
	Returns true if the set is empty.
auto	reset () noexcept -> void
	Remove every CPU from the set.
auto	set (usize cpu, memory_order order=memory_order::seq_cst) noexcept -> void
	Atomically add a CPU to the set.
auto	set_relaxed (usize cpu) noexcept -> void
	Non-atomically add a CPU (use only when externally serialized).
auto	test (usize cpu, memory_order order=memory_order::relaxed) const noexcept -> bool
	Atomically test whether a CPU is in the set.

Static Public Member Functions
static constexpr auto	capacity () noexcept -> usize
	Maximum number of CPUs this mask can represent.

Detailed Description

A fixed-capacity, SMP-aware set of CPU identifiers.

Note

No heap allocation; the storage is static, like static_bitmap.

Member Function Documentation

clear()

auto lib::cpumask::clear ( usize cpu, memory_order order = memory_order::seq_cst )->void

inlineexportnoexcept

Atomically remove a CPU from the set.

Parameters

[in]	cpu	CPU identifier (0 to capacity()-1).
[in]	order	Memory ordering (default seq_cst).

first_set()

auto lib::cpumask::first_set ( ) const->std::optional< usize >

inlinenodiscardexportnoexcept

Index of the lowest-numbered member.

Returns

The CPU id, or nullopt if the set is empty.

for_each()

template<typename Fn>

auto lib::cpumask::for_each ( Fn && fn, memory_order confirm = memory_order::acquire ) const->void

inlineexportnoexcept

Invoke fn for every member CPU, in ascending id order.

Template Parameters

Fn	Callable invocable as fn(u16 cpu).

Parameters

[in]	fn	Callback receiving each member CPU id.
[in]	confirm	Memory ordering used to re-confirm membership.

next_set()

auto lib::cpumask::next_set ( usize after ) const->std::optional< usize >

inlinenodiscardexportnoexcept

Index of the lowest-numbered member strictly after after.

Parameters

[in]

after

Index to search past (the result is always > after).

Returns

The next member CPU id, or nullopt if none follows.

set()

auto lib::cpumask::set ( usize cpu, memory_order order = memory_order::seq_cst )->void

inlineexportnoexcept

Atomically add a CPU to the set.

Parameters

[in]	cpu	CPU identifier (0 to capacity()-1).
[in]	order	Memory ordering (default seq_cst).

test()

auto lib::cpumask::test ( usize cpu, memory_order order = memory_order::relaxed ) const->bool

inlinenodiscardexportnoexcept

Atomically test whether a CPU is in the set.

Parameters

[in]	cpu	CPU identifier (0 to capacity()-1).
[in]	order	Memory ordering (default relaxed).

Returns

true if the CPU is a member.

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The documentation for this class was generated from the following file:

• lib/cpumask.cxxm