package hostmm

import "gvisor.dev/gvisor/pkg/sentry/hostmm"

Package hostmm provides tools for interacting with the host Linux kernel's virtual memory management subsystem.

Index ¶

• func GetTransparentHugepageEnum(data string) (string, error)
• func GlobalMemoryBarrier() error
• func HaveGlobalMemoryBarrier() bool
• func HaveProcessMemoryBarrier() bool
• func NotifyCurrentMemcgPressureCallback(f func(), level string) (func(), error)
• func ProcessMemoryBarrier() error
• func ReadTransparentHugepageEnum(filename string) (string, error)

Functions ¶

func GetTransparentHugepageEnum ¶

func GetTransparentHugepageEnum(data string) (string, error)

GetTransparentHugepageEnum returns the currently selected option given the contents of any of /sys/kernel/mm/transparent_hugepage/{enabled,shmem_enabled,defrag}.

func GlobalMemoryBarrier ¶

func GlobalMemoryBarrier() error

GlobalMemoryBarrier blocks until "all running threads [in the host OS] have passed through a state where all memory accesses to user-space addresses match program order between entry to and return from GlobalMemoryBarrier", as for membarrier(2).

Preconditions: HaveGlobalMemoryBarrier() == true.

func HaveGlobalMemoryBarrier ¶

func HaveGlobalMemoryBarrier() bool

HaveGlobalMemoryBarrier returns true if GlobalMemoryBarrier is supported.

func HaveProcessMemoryBarrier ¶

func HaveProcessMemoryBarrier() bool

HaveProcessMemoryBarrier returns true if ProcessMemoryBarrier is supported.

func NotifyCurrentMemcgPressureCallback ¶

func NotifyCurrentMemcgPressureCallback(f func(), level string) (func(), error)

NotifyCurrentMemcgPressureCallback requests that f is called whenever the calling process' memory cgroup indicates memory pressure of the given level, as specified by Linux's Documentation/cgroup-v1/memory.txt.

If NotifyCurrentMemcgPressureCallback succeeds, it returns a function that terminates the requested memory pressure notifications. This function may be called at most once.

func ProcessMemoryBarrier ¶

func ProcessMemoryBarrier() error

ProcessMemoryBarrier is equivalent to GlobalMemoryBarrier, but only synchronizes with threads sharing a virtual address space (from the host OS' perspective) with the calling thread.

Preconditions: HaveProcessMemoryBarrier() == true.

func ReadTransparentHugepageEnum ¶

func ReadTransparentHugepageEnum(filename string) (string, error)

ReadTransparentHugepageEnum returns the currently selected option for whichever of /sys/kernel/mm/transparent_hugepage/{enabled,shmem_enabled,defrag} is specified by filename. (Only the basename is required, not the full path.)

Source Files ¶

cgroup.go hostmm.go membarrier.go