diff options
Diffstat (limited to 'vendor/github.com/cilium/ebpf/link/tracepoint.go')
-rw-r--r-- | vendor/github.com/cilium/ebpf/link/tracepoint.go | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/vendor/github.com/cilium/ebpf/link/tracepoint.go b/vendor/github.com/cilium/ebpf/link/tracepoint.go new file mode 100644 index 000000000..a59ef9d1c --- /dev/null +++ b/vendor/github.com/cilium/ebpf/link/tracepoint.go @@ -0,0 +1,77 @@ +package link + +import ( + "fmt" + + "github.com/cilium/ebpf" +) + +// TracepointOptions defines additional parameters that will be used +// when loading Tracepoints. +type TracepointOptions struct { + // Arbitrary value that can be fetched from an eBPF program + // via `bpf_get_attach_cookie()`. + // + // Needs kernel 5.15+. + Cookie uint64 +} + +// Tracepoint attaches the given eBPF program to the tracepoint with the given +// group and name. See /sys/kernel/debug/tracing/events to find available +// tracepoints. The top-level directory is the group, the event's subdirectory +// is the name. Example: +// +// tp, err := Tracepoint("syscalls", "sys_enter_fork", prog, nil) +// +// Losing the reference to the resulting Link (tp) will close the Tracepoint +// and prevent further execution of prog. The Link must be Closed during +// program shutdown to avoid leaking system resources. +// +// Note that attaching eBPF programs to syscalls (sys_enter_*/sys_exit_*) is +// only possible as of kernel 4.14 (commit cf5f5ce). +func Tracepoint(group, name string, prog *ebpf.Program, opts *TracepointOptions) (Link, error) { + if group == "" || name == "" { + return nil, fmt.Errorf("group and name cannot be empty: %w", errInvalidInput) + } + if prog == nil { + return nil, fmt.Errorf("prog cannot be nil: %w", errInvalidInput) + } + if !isValidTraceID(group) || !isValidTraceID(name) { + return nil, fmt.Errorf("group and name '%s/%s' must be alphanumeric or underscore: %w", group, name, errInvalidInput) + } + if prog.Type() != ebpf.TracePoint { + return nil, fmt.Errorf("eBPF program type %s is not a Tracepoint: %w", prog.Type(), errInvalidInput) + } + + tid, err := getTraceEventID(group, name) + if err != nil { + return nil, err + } + + fd, err := openTracepointPerfEvent(tid, perfAllThreads) + if err != nil { + return nil, err + } + + var cookie uint64 + if opts != nil { + cookie = opts.Cookie + } + + pe := &perfEvent{ + typ: tracepointEvent, + group: group, + name: name, + tracefsID: tid, + cookie: cookie, + fd: fd, + } + + lnk, err := attachPerfEvent(pe, prog) + if err != nil { + pe.Close() + return nil, err + } + + return lnk, nil +} |