Song Liu wrote: > Add .test_run for raw_tracepoint. Also, introduce a new feature that runs > the target program on a specific CPU. This is achieved by a new flag in > bpf_attr.test, cpu_plus. For compatibility, cpu_plus == 0 means run the > program on current cpu, cpu_plus > 0 means run the program on cpu with id > (cpu_plus - 1). This feature is needed for BPF programs that handle > perf_event and other percpu resources, as the program can access these > resource locally. > > Signed-off-by: Song Liu <[email protected]> > ---
Acked-by: John Fastabend <[email protected]> [...] > + > +int bpf_prog_test_run_raw_tp(struct bpf_prog *prog, > + const union bpf_attr *kattr, > + union bpf_attr __user *uattr) > +{ > + void __user *ctx_in = u64_to_user_ptr(kattr->test.ctx_in); > + __u32 ctx_size_in = kattr->test.ctx_size_in; > + struct bpf_raw_tp_test_run_info info; > + int cpu, err = 0; > + > + /* doesn't support data_in/out, ctx_out, duration, or repeat */ > + if (kattr->test.data_in || kattr->test.data_out || > + kattr->test.ctx_out || kattr->test.duration || > + kattr->test.repeat) > + return -EINVAL; > + > + if (ctx_size_in < prog->aux->max_ctx_offset) > + return -EINVAL; > + > + if (ctx_size_in) { > + info.ctx = kzalloc(ctx_size_in, GFP_USER); > + if (!info.ctx) > + return -ENOMEM; > + if (copy_from_user(info.ctx, ctx_in, ctx_size_in)) { > + err = -EFAULT; > + goto out; > + } > + } else { > + info.ctx = NULL; > + } > + > + info.prog = prog; > + cpu = kattr->test.cpu_plus - 1; > + > + if (!kattr->test.cpu_plus || cpu == smp_processor_id()) { > + __bpf_prog_test_run_raw_tp(&info); > + } else { > + /* smp_call_function_single() also checks cpu_online() > + * after csd_lock(). However, since cpu_plus is from user > + * space, let's do an extra quick check to filter out > + * invalid value before smp_call_function_single(). > + */ > + if (!cpu_online(cpu)) { > + err = -ENXIO; > + goto out; > + } > + > + err = smp_call_function_single(cpu, __bpf_prog_test_run_raw_tp, > + &info, 1); > + if (err) > + goto out; > + } > + > + if (copy_to_user(&uattr->test.retval, &info.retval, sizeof(u32))) { > + err = -EFAULT; > + goto out; > + } This goto is not needed. I don't mind it though. > + > +out: > + kfree(info.ctx); > + return err; > +} > +
