bpf

Documentation

Index

• Constants
• func CheckOrMountCgroup2() error
• func CheckOrMountDebugFS() error
• func CheckOrMountFS(bpfRoot string)
• func ConfigureResourceLimits() error
• func Environment() []string
• func GetMapRoot() string
• func GetNumPossibleCPUs() int
• func HasBuildId() bool
• func HasKprobeMulti() bool
• func HasModifyReturn() bool
• func HasOverrideHelper() bool
• func LocalMapName(name string, id uint16) string
• func LocalMapPath(name string, id uint16) string
• func LogFeatures() string
• func MapPath(name string) string
• func MapPrefixPath() string
• func SetMapPrefix(path string)
• func SetMapRoot(path string)
• func UpdateElementFromPointers(fd int, structPtr, sizeOfStruct uintptr) error
• type Feature
• type PerfEventConfig
  • func DefaultPerfEventConfig() *PerfEventConfig

Constants

const (
	PERF_TYPE_SOFTWARE = 1

	PERF_SAMPLE_RAW          = 1 << 10
	PERF_COUNT_SW_BPF_OUTPUT = 10

	// BPF map type constants. Must match enum bpf_map_type from linux/bpf.h
	BPF_MAP_TYPE_UNSPEC              = 0
	BPF_MAP_TYPE_HASH                = 1
	BPF_MAP_TYPE_ARRAY               = 2
	BPF_MAP_TYPE_PROG_ARRAY          = 3
	BPF_MAP_TYPE_PERF_EVENT_ARRAY    = 4
	BPF_MAP_TYPE_PERCPU_HASH         = 5
	BPF_MAP_TYPE_PERCPU_ARRAY        = 6
	BPF_MAP_TYPE_STACK_TRACE         = 7
	BPF_MAP_TYPE_CGROUP_ARRAY        = 8
	BPF_MAP_TYPE_LRU_HASH            = 9
	BPF_MAP_TYPE_LRU_PERCPU_HASH     = 10
	BPF_MAP_TYPE_LPM_TRIE            = 11
	BPF_MAP_TYPE_ARRAY_OF_MAPS       = 12
	BPF_MAP_TYPE_HASH_OF_MAPS        = 13
	BPF_MAP_TYPE_DEVMAP              = 14
	BPF_MAP_TYPE_SOCKMAP             = 15
	BPF_MAP_TYPE_CPUMAP              = 16
	BPF_MAP_TYPE_XSKMAP              = 17
	BPF_MAP_TYPE_SOCKHASH            = 18
	BPF_MAP_TYPE_CGROUP_STORAGE      = 19
	BPF_MAP_TYPE_REUSEPORT_SOCKARRAY = 20

	// BPF syscall command constants. Must match enum bpf_cmd from linux/bpf.h
	BPF_MAP_CREATE          = 0
	BPF_MAP_LOOKUP_ELEM     = 1
	BPF_MAP_UPDATE_ELEM     = 2
	BPF_MAP_DELETE_ELEM     = 3
	BPF_MAP_GET_NEXT_KEY    = 4
	BPF_PROG_LOAD           = 5
	BPF_OBJ_PIN             = 6
	BPF_OBJ_GET             = 7
	BPF_PROG_ATTACH         = 8
	BPF_PROG_DETACH         = 9
	BPF_PROG_TEST_RUN       = 10
	BPF_PROG_GET_NEXT_ID    = 11
	BPF_MAP_GET_NEXT_ID     = 12
	BPF_PROG_GET_FD_BY_ID   = 13
	BPF_MAP_GET_FD_BY_ID    = 14
	BPF_OBJ_GET_INFO_BY_FD  = 15
	BPF_PROG_QUERY          = 16
	BPF_RAW_TRACEPOINT_OPEN = 17
	BPF_BTF_LOAD            = 18
	BPF_BTF_GET_FD_BY_ID    = 19
	BPF_TASK_FD_QUERY       = 20

	// BPF syscall attach types
	BPF_CGROUP_INET_INGRESS     = 0
	BPF_CGROUP_INET_EGRESS      = 1
	BPF_CGROUP_INET_SOCK_CREATE = 2
	BPF_CGROUP_SOCK_OPS         = 3
	BPF_SK_SKB_STREAM_PARSER    = 4
	BPF_SK_SKB_STREAM_VERDICT   = 5
	BPF_CGROUP_DEVICE           = 6
	BPF_SK_MSG_VERDICT          = 7
	BPF_CGROUP_INET4_BIND       = 8
	BPF_CGROUP_INET6_BIND       = 9
	BPF_CGROUP_INET4_CONNECT    = 10
	BPF_CGROUP_INET6_CONNECT    = 11
	BPF_CGROUP_INET4_POST_BIND  = 12
	BPF_CGROUP_INET6_POST_BIND  = 13
	BPF_CGROUP_UDP4_SENDMSG     = 14
	BPF_CGROUP_UDP6_SENDMSG     = 15
	BPF_LIRC_MODE2              = 16
	BPF_FLOW_DISSECTOR          = 17
	BPF_CGROUP_SYSCTL           = 18
	BPF_CGROUP_UDP4_RECVMSG     = 19
	BPF_CGROUP_UDP6_RECVMSG     = 20

	// Flags for BPF_MAP_UPDATE_ELEM. Must match values from linux/bpf.h
	BPF_ANY     = 0
	BPF_NOEXIST = 1
	BPF_EXIST   = 2

	// Flags for BPF_MAP_CREATE. Must match values from linux/bpf.h
	BPF_F_NO_PREALLOC   = 1 << 0
	BPF_F_NO_COMMON_LRU = 1 << 1
	BPF_F_NUMA_NODE     = 1 << 2

	// Flags for BPF_PROG_QUERY
	BPF_F_QUERY_EFFECTVE = 1 << 0

	// Flags for accessing BPF object
	BPF_F_RDONLY = 1 << 3
	BPF_F_WRONLY = 1 << 4

	// Flag for stack_map, store build_id+offset instead of pointer
	BPF_F_STACK_BUILD_ID = 1 << 5

	// Build ID flags bit for perf_event_open
	PerfBitBuildId = unix.CBitFieldMaskBit34
)

const (
	PossibleCPUSysfsPath = "/sys/devices/system/cpu/possible"
)

Functions

func CheckOrMountCgroup2

func CheckOrMountCgroup2() error

func CheckOrMountDebugFS

func CheckOrMountDebugFS() error

func CheckOrMountFS

func CheckOrMountFS(bpfRoot string)

CheckOrMountFS checks or mounts the BPF filesystem and then opens/creates/deletes all maps which have previously been scheduled to be opened/created/deleted.

func ConfigureResourceLimits

func ConfigureResourceLimits() error

func Environment

func Environment() []string

Environment returns a list of environment variables which are needed to make BPF programs and tc aware of the actual BPFFS mount path.

func GetMapRoot

func GetMapRoot() string

func GetNumPossibleCPUs

func GetNumPossibleCPUs() int

GetNumPossibleCPUs returns a total number of possible CPUS, i.e. CPUs that have been allocated resources and can be brought online if they are present. The number is retrieved by parsing /sys/device/system/cpu/possible.

See https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/linux/cpumask.h?h=v4.19#n50 for more details.

func HasBuildId

func HasBuildId() bool

func HasKprobeMulti

func HasKprobeMulti() bool

func HasModifyReturn

func HasModifyReturn() bool

func HasOverrideHelper

func HasOverrideHelper() bool

func LocalMapName

func LocalMapName(name string, id uint16) string

LocalMapName returns the name for a BPF map that is local to the specified ID.

func LocalMapPath

func LocalMapPath(name string, id uint16) string

LocalMapPath returns the path for a BPF map that is local to the specified ID.

func LogFeatures

func LogFeatures() string

func MapPath

func MapPath(name string) string

MapPath returns a path for a BPF map with a given name.

func MapPrefixPath

func MapPrefixPath() string

func SetMapPrefix

func SetMapPrefix(path string)

func SetMapRoot

func SetMapRoot(path string)

func UpdateElementFromPointers

func UpdateElementFromPointers(fd int, structPtr, sizeOfStruct uintptr) error

Types

type Feature

type Feature struct {
	// contains filtered or unexported fields
}

type PerfEventConfig

type PerfEventConfig struct {
	NumCpus      int
	NumPages     int
	MapName      string
	Type         int
	Config       int
	SampleType   int
	WakeupEvents int
}

func DefaultPerfEventConfig

func DefaultPerfEventConfig() *PerfEventConfig

DefaultPerfEventConfig returns the default perf event configuration. It relies on the map root to be set.