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KFuncs (Linux)

Stability guarantees

Helper functions enjoy the stability guarantee offered by the user API, as explained in documentation about stability guarantees of the helper functions. But KFuncs do not enjoy those same guarantees.

Although KFuncs are not expected to be very volatile, defensive programming techniques are still advised. Otherwise helper functions should be preferred over KFuncs.

cGroup statistics KFuncs

cGroup resource statistics KFuncs

These KFuncs are used to update or flush cGroup resource statistics efficiently.

cGroup memory statistics KFuncs

These KFuncs are used to read and flush cGroup memory statistics.

Key signature verification KFuncs

These KFuncs are used to verify PKCS#7 signed data against keys from a key-ring.

CPU mask KFuncs

Generic KFuncs

Object allocation KFuncs

A set of KFuncs to allocate and deallocate custom objects for the purposes of building custom data structures.

BPF linked list KFuncs

BPF Arena KFuncs

KFuncs used to allocate and free pages from an arena.

BPF task KFuncs

Kfuncs used to acquire and release task reference.

BPF Red-Black-tree KFuncs

Kfuncs used to create and modify red-black trees.

Kfuncs for acquiring and releasing cGroup references

These kfuncs allow you to take a reference to a cGroup and store them as kptrs in maps.

Kfuncs for querying tasks

KFuncs for memory allocator inspection

Kfuncs for casting pointers

Kfuncs for taking and releasing RCU read locks

Kfuncs for dynamic pointer slices

Open coded iterators

Kfuncs for open coded numeric iterators

Kfuncs for open coded virtual memory area iterators

Kfuncs for open coded task cGroup iterators

Kfuncs for open coded cGroup iterators

Kfuncs for open coded task iterators

Kfuncs for bits

Kfuncs for slab memory allocation iterators

Kfuncs for sched_ext dispatch queue iterators

Kfuncs for DMA buffer iterators

Kfuncs for dynamic pointers

Preemption KFuncs

Work-queue KFuncs

Misc KFuncs

Timer KFuncs

XDP metadata kfuncs

XDP/SKB dynamic pointer kfuncs

Network crypto kfuncs

BBR congestion control kfuncs

Cubic TCP congestion control kfuncs

DC TCP congestion control kfuncs

TCP Reno congestion control kfuncs

Foo over UDP KFuncs

Connection tracking KFuncs

XDP KFuncs

XFRM KFuncs

HID Kfuncs

KProbe session Kfuncs

Memory probe Kfuncs

IRQ Kfuncs

sched_ext Kfuncs

Dispatch Queue Kfuncs

Dispatch Kfuncs

Error and debug Kfuncs

CPU performance Kfuncs

CPU mask Kfuncs

Idle CPU mask Kfuncs

Task Kfuncs

CID flavor Kfuncs

NUMA Kfuncs

Resilient Queued spinlock Kfuncs

Sock ops Kfuncs

Memory probe to dynptr Kfuncs

File dynptr Kfuncs

BPF Qdisc kfuncs

String Kfuncs

Debug stream Kfuncs

CGroup xattr Kfuncs

Task work schedule Kfuncs

I/O Userspace Ring Kfuncs

Wake up sources Kfuncs

These kfuncs allow for the iteration of wake-up sources in BPF, which is faster than iteration in userspace via sysfs/debugfs.