internal/c/filter.c


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//+build ignore

#define ACCEPT 0
#define FILTER 1

static __always_inline int filter(__u32 *pid, __u32 *tid) {
    u64 pid_tgid = bpf_get_current_pid_tgid();
    *pid = pid_tgid >> 32;

    // Ignore ior userland process itself
    if (*pid == IOR_PID_FILTER) {
        return FILTER;
    }
    
    *tid = pid_tgid & 0xFFFFFFFF;
    if (-1 == PID_FILTER || *pid == PID_FILTER) {
        if (-1 == TID_FILTER || *tid == TID_FILTER) {
            return ACCEPT;
        }
    }

    return FILTER;
}