Move BPF setup off flags.Flags

1 files changed, 45 insertions, 0 deletions

diff --git a/internal/bpfsetup.go b/internal/bpfsetup.go
new file mode 100644
index 0000000..9791930
--- /dev/null
+++ b/internal/bpfsetup.go
@@ -0,0 +1,45 @@
+package internal
+
+import (
+	"fmt"
+	"os"
+
+	"ior/internal/flags"
+
+	bpf "github.com/aquasecurity/libbpfgo"
+)
+
+func setBPFGlobals(cfg flags.Flags, bpfModule *bpf.Module) error {
+	// Ignore `ior` process itself from the filter.
+	if err := bpfModule.InitGlobalVariable("IOR_PID_FILTER", uint32(os.Getpid())); err != nil {
+		return fmt.Errorf("unable set IOR_PID_FILTER: %w", err)
+	}
+	if err := bpfModule.InitGlobalVariable("PID_FILTER", uint32(cfg.PidFilter)); err != nil {
+		return fmt.Errorf("unable to set up PID_FILTER global variable: %w", err)
+	}
+	if err := bpfModule.InitGlobalVariable("TID_FILTER", uint32(cfg.TidFilter)); err != nil {
+		return fmt.Errorf("unable to set up TID_FILTER global variable: %w", err)
+	}
+	return nil
+}
+
+func resizeBPFMaps(cfg flags.Flags, bpfModule *bpf.Module) error {
+	if err := resizeBPFMap(bpfModule, "event_map", uint32(cfg.EventMapSize)); err != nil {
+		return fmt.Errorf("event_map: %w", err)
+	}
+	return nil
+}
+
+func resizeBPFMap(module *bpf.Module, name string, size uint32) error {
+	m, err := module.GetMap(name)
+	if err != nil {
+		return err
+	}
+	if err = m.SetMaxEntries(size); err != nil {
+		return err
+	}
+	if actual := m.MaxEntries(); actual != size {
+		return fmt.Errorf("map resize to %d failed, expected %v, actual %v", size, size, actual)
+	}
+	return nil
+}