Class: OsCtl::Lib::CpuMask

Inherits:
Object
  • Object
show all
Defined in:
lib/libosctl/cpu_mask.rb

Overview

Interface for CPU masks

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(mask) ⇒ CpuMask

Returns a new instance of CpuMask.

Parameters:

  • mask (String, Array<Integer>) 


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# File 'lib/libosctl/cpu_mask.rb', line 13

def initialize(mask)
  @cpu_list =
    if mask.is_a?(String)
      parse_cpus(mask)
    elsif mask.is_a?(Array)
      mask
    else
      raise ArgumentError, 'mask can be either a string or a list of integers'
    end
end

Class Method Details

.format(mask) ⇒ String

Parameters:

  • mask (Array<Integer>)

Returns:

  • (String) 


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# File 'lib/libosctl/cpu_mask.rb', line 8

def self.format(mask)
  new(mask).to_s
end

Instance Method Details

#&(other) ⇒ CpuMask

Return an intersection of self with other mask as a new mask

Parameters:

Returns:



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# File 'lib/libosctl/cpu_mask.rb', line 38

def &(other)
  self.class.new(to_a & other.to_a)
end

#all_range ⇒ Object (protected) 



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# File 'lib/libosctl/cpu_mask.rb', line 104

def all_range
  @all_range ||= (0..(Etc.nprocessors - 1))
end

#each {|cpu| ... } ⇒ Object

Yield Parameters:

  • cpu (Integer) 


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# File 'lib/libosctl/cpu_mask.rb', line 53

def each(&)
  if @cpu_list == :all
    all_range.each(&)
  else
    @cpu_list.each(&)
  end
end

#format(cpu_list) ⇒ Object (protected) 



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# File 'lib/libosctl/cpu_mask.rb', line 108

def format(cpu_list)
  return if cpu_list.empty?

  groups = []
  acc = []
  prev = nil

  cpu_list.each do |cpu|
    if prev.nil? || cpu == prev + 1
      prev = cpu
      acc << cpu
    else
      groups << format_range(acc)
      prev = nil
      acc = [cpu]
    end
  end

  groups << format_range(acc)
  groups.join(',')
end

#format_range(acc) ⇒ Object (protected) 



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# File 'lib/libosctl/cpu_mask.rb', line 130

def format_range(acc)
  len = acc.length

  if len == 1
    acc.first
  elsif len == 2
    acc.join(',')
  elsif len > 2
    "#{acc.first}-#{acc.last}"
  end
end

#include?(cpu) ⇒ Boolean

Check if the mask includes a particular CPU

Parameters:

  • cpu (Integer)

Returns:

  • (Boolean) 


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# File 'lib/libosctl/cpu_mask.rb', line 27

def include?(cpu)
  if @cpu_list == :all
    true
  else
    @cpu_list.include?(cpu)
  end
end

#parse_cpus(str) ⇒ Object (protected) 



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# File 'lib/libosctl/cpu_mask.rb', line 78

def parse_cpus(str)
  return :all if str == '*'

  ret = []

  str.split(',').each do |grp|
    sep = grp.index('-')

    if sep
      parts = grp.split('-')

      if parts.length != 2
        raise ArgumentError, "invalid cpu mask #{str.inspect}"
      end

      first, last = parts
      ret.concat((first.to_i..last.to_i).to_a)
    else
      ret << grp.to_i
    end
  end

  ret.sort!
  ret
end

#size ⇒ Integer

Return the number of CPUs

Returns:

  • (Integer) 


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# File 'lib/libosctl/cpu_mask.rb', line 44

def size
  if @cpu_list == :all
    all_range.size
  else
    @cpu_list.size
  end
end

#to_a ⇒ Array<Integer>

Return CPUs as an array

Returns:

  • (Array<Integer>) 


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# File 'lib/libosctl/cpu_mask.rb', line 63

def to_a
  if @cpu_list == :all
    all_range.to_a
  else
    @cpu_list
  end
end

#to_s ⇒ String

Returns:

  • (String) 


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# File 'lib/libosctl/cpu_mask.rb', line 72

def to_s
  @to_s ||= format(@cpu_list == :all ? all_range : @cpu_list)
end