os_cpu.h File Reference

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Classes
class	os_cpu_ScopedSetThreadAffinityMask

Namespaces
	ERR
	Introduction

Typedefs
typedef void(*	OsCpuCallback) (size_t processor, uintptr_t cbData)
	called by os_cpu_CallByEachCPU. More...

Functions
uintptr_t	os_cpu_ProcessorMask ()
size_t	os_cpu_NumProcessors ()
double	os_cpu_ClockFrequency ()
size_t	os_cpu_PageSize ()
size_t	os_cpu_LargePageSize ()
size_t	os_cpu_QueryMemorySize ()
size_t	os_cpu_MemorySize ()
size_t	os_cpu_MemoryAvailable ()
uintptr_t	os_cpu_SetThreadAffinityMask (uintptr_t processorMask)
	restrict the current thread to a set of processors. More...
Status	os_cpu_CallByEachCPU (OsCpuCallback cb, uintptr_t cbData)
	execute the specified function once on each processor. More...

Variables
const Status	ERR::OS_CPU_RESTRICTED_AFFINITY = -130100
static const size_t	os_cpu_MaxProcessors = sizeof(uintptr_t)*CHAR_BIT
	maximum number of processors supported by the OS (determined by the number of bits in an affinity mask) More...

Typedef Documentation

OsCpuCallback

typedef void(* OsCpuCallback) (size_t processor, uintptr_t cbData)

called by os_cpu_CallByEachCPU.

Parameters

processor	ID of processor running the current thread for the duration of this function.
cbData	user-specified data passed through os_cpu_CallByEachCPU.

Function Documentation

os_cpu_CallByEachCPU()

Status os_cpu_CallByEachCPU	(	OsCpuCallback	cb,
		uintptr_t	cbData
	)

execute the specified function once on each processor.

this proceeds serially (the callback is never reentered) in increasing order of processor ID. fails if process affinity prevents running on all processors.

os_cpu_ClockFrequency()

double os_cpu_ClockFrequency

(

)

Returns

a rough estimate of the CPU clock frequency. this is usually accurate to a few MHz and is faster than measurement loops.

os_cpu_LargePageSize()

size_t os_cpu_LargePageSize

(

)

Returns

the size [bytes] of a large MMU page (4 MiB on most IA-32 systems) or zero if they are not supported.

os_cpu_MemoryAvailable()

size_t os_cpu_MemoryAvailable

(

)

Returns

the current amount [MB] of available memory.

os_cpu_MemorySize()

size_t os_cpu_MemorySize

(

)

Returns

the size [MB] of physical memory; caches the result of os_cpu_QueryMemorySize and overrides it with a more exact value if SMBIOS information is available.

os_cpu_NumProcessors()

size_t os_cpu_NumProcessors

(

)

Returns

the number of processors available to this process.

note: this function is necessary because POSIX sysconf _SC_NPROCESSORS_CONF is not suppored on MacOSX, else we would use that.

os_cpu_PageSize()

size_t os_cpu_PageSize

(

)

Returns

the size [bytes] of a MMU page (4096 on most IA-32 systems)

os_cpu_ProcessorMask()

uintptr_t os_cpu_ProcessorMask

(

)

Returns

bit mask of processors that exist and are available to this process. its population count is by definition equal to os_cpu_NumProcessors().

os_cpu_QueryMemorySize()

size_t os_cpu_QueryMemorySize

(

)

Returns

the size [MB] of physical memory as reported by the OS; no caching/validation is performed.

os_cpu_SetThreadAffinityMask()

uintptr_t os_cpu_SetThreadAffinityMask

(

uintptr_t

processorMask

)

restrict the current thread to a set of processors.

Parameters

processorMask

a bit mask of acceptable processors (bit index i corresponds to processor i)

Returns

the previous mask

Variable Documentation

os_cpu_MaxProcessors

const size_t os_cpu_MaxProcessors = sizeof(uintptr_t)*CHAR_BIT

static

maximum number of processors supported by the OS (determined by the number of bits in an affinity mask)