Re: [PATCH] rust: add seqfile abstraction

[Alice Ryhl <aliceryhl@google.com>]

On Tue, Oct 1, 2024 at 11:07 AM Alice Ryhl <aliceryhl@google.com> wrote:
>
> This adds a simple seq file abstraction that lets you print to a seq
> file using ordinary Rust printing syntax.
>
> An example user from Rust Binder:
>
>     pub(crate) fn full_debug_print(
>         &self,
>         m: &SeqFile,
>         owner_inner: &mut ProcessInner,
>     ) -> Result<()> {
>         let prio = self.node_prio();
>         let inner = self.inner.access_mut(owner_inner);
>         seq_print!(
>             m,
>             "  node {}: u{:016x} c{:016x} pri {}:{} hs {} hw {} cs {} cw {}",
>             self.debug_id,
>             self.ptr,
>             self.cookie,
>             prio.sched_policy,
>             prio.prio,
>             inner.strong.has_count,
>             inner.weak.has_count,
>             inner.strong.count,
>             inner.weak.count,
>         );
>         if !inner.refs.is_empty() {
>             seq_print!(m, " proc");
>             for node_ref in &inner.refs {
>                 seq_print!(m, " {}", node_ref.process.task.pid());
>             }
>         }
>         seq_print!(m, "\n");
>         for t in &inner.oneway_todo {
>             t.debug_print_inner(m, "    pending async transaction ");
>         }
>         Ok(())
>     }
>
> The `SeqFile` type is marked not thread safe so that `call_printf` can
> be a `&self` method. The alternative is to use `self: Pin<&mut Self>`
> which is inconvenient, or to have `SeqFile` wrap a pointer instead of
> wrapping the C struct directly.
>
> Signed-off-by: Alice Ryhl <aliceryhl@google.com>

It's supposed to say this below the --- line:

This series is based on top of vfs.rust.file for the NotThreadSafe type.

I have no idea why b4 decided to drop this information ...

Alice