[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <Y3eblFzToIh4hL8m@maniforge.lan>
Date: Fri, 18 Nov 2022 08:49:56 -0600
From: David Vernet <void@...ifault.com>
To: Alexei Starovoitov <alexei.starovoitov@...il.com>
Cc: bpf@...r.kernel.org, ast@...nel.org, andrii@...nel.org,
daniel@...earbox.net, martin.lau@...ux.dev, memxor@...il.com,
yhs@...com, song@...nel.org, sdf@...gle.com,
john.fastabend@...il.com, kpsingh@...nel.org, jolsa@...nel.org,
haoluo@...gle.com, tj@...nel.org, kernel-team@...com,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH bpf-next v7 3/3] bpf/selftests: Add selftests for new
task kfuncs
On Thu, Nov 17, 2022 at 06:21:00PM -0800, Alexei Starovoitov wrote:
[...]
> > +static inline int tasks_kfunc_map_insert(struct task_struct *p)
> > +{
> > + struct __tasks_kfunc_map_value local, *v;
> > + long status;
> > + struct task_struct *acquired, *old;
> > + s32 pid;
> > +
> > + status = bpf_probe_read_kernel(&pid, sizeof(pid), &p->pid);
> > + if (status)
> > + return status;
> > +
> > + local.task = NULL;
> > + status = bpf_map_update_elem(&__tasks_kfunc_map, &pid, &local, BPF_NOEXIST);
> > + if (status)
> > + return status;
> > +
> > + v = bpf_map_lookup_elem(&__tasks_kfunc_map, &pid);
> > + if (!v) {
> > + bpf_map_delete_elem(&__tasks_kfunc_map, &pid);
> > + return status;
>
> here it will return 0, but probably should be returning error?
Ah, yes this should be returning -ENOENT. Thanks for catching this.
[...]
> > +SEC("tp_btf/task_newtask")
> > +int BPF_PROG(task_kfunc_release_null, struct task_struct *task, u64 clone_flags)
> > +{
> > + struct __tasks_kfunc_map_value local, *v;
> > + long status;
> > + struct task_struct *acquired, *old;
> > + s32 pid;
> > +
> > + status = bpf_probe_read_kernel(&pid, sizeof(pid), &task->pid);
> > + if (status)
> > + return 0;
> > +
> > + local.task = NULL;
> > + status = bpf_map_update_elem(&__tasks_kfunc_map, &pid, &local, BPF_NOEXIST);
> > + if (status)
> > + return status;
> > +
> > + v = bpf_map_lookup_elem(&__tasks_kfunc_map, &pid);
> > + if (!v)
> > + return status;
>
> should be return error instead?
Yep, here as well.
I'll fix both of these in v8.
[...]
Powered by blists - more mailing lists