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=?utf-8?B?Mks5MlM2bGtERHBFYkdnK2E1TXRXMmZXd3AvTGpKYTZ3Y1VkNEh4dz09?= X-OriginatorOrg: garyguo.net X-MS-Exchange-CrossTenant-Network-Message-Id: 4e5a1bb8-ffb0-427a-4dc9-08df0a776729 X-MS-Exchange-CrossTenant-AuthSource: LOAP265MB8560.GBRP265.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Sep 2026 11:26:45.8945 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: bbc898ad-b10f-4e10-8552-d9377b823d45 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Qdf+4NJ0UOTR7oazIAmdsav7At3bvEFFhCX1yyozT0LC0rqTJe/zdkaNuP67INDTFfUqVajZCAW8N2EeAuD2oQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CWLP265MB6247 On Fri Sep 4, 2026 at 12:13 PM BST, Alexandre Courbot wrote: > On Thu Sep 3, 2026 at 12:15 PM JST, John Hubbard wrote: > <...> >> @@ -611,15 +621,39 @@ pub(crate) fn send_command_no_wait(&self, bar: = Bar0<'_>, command: M) -> Resul >> self.inner.lock().send_command(bar, command) >> } >> =20 >> - /// Receive a message from the GSP. >> + /// Waits for an unsolicited GSP event of type `M`, logging any oth= er event that arrives >> + /// first. >> + /// >> + /// The queue is locked for the whole wait, for up to [`Self::RECEI= VE_TIMEOUT`], so a >> + /// concurrent command cannot consume the awaited event. >> /// >> - /// See [`CmdqInner::receive_msg`] for details. >> - pub(crate) fn receive_msg(&self, timeout: Delta)= -> Result >> + /// # Errors >> + /// >> + /// - `ETIMEDOUT` if the event does not arrive within [`Self::RECEI= VE_TIMEOUT`] of the call, >> + /// however many other events arrive while waiting. >> + /// - `EIO` if the queue is poisoned or a message fails framing or = checksum validation (see >> + /// [`CmdqInner::wait_for_msg`]). > > Let's not mention private methods in public documentation. > >> + /// >> + /// Error codes returned by [`MessageFromGsp::read`] are propagated= as-is. >> + pub(crate) fn await_msg(&self) -> Result >> where >> // This allows all error types, including `Infallible`, to be u= sed for `M::InitError`. >> Error: From, >> { >> - self.inner.lock().receive_msg(timeout) >> + let mut inner =3D self.inner.lock(); >> + >> + let deadline =3D Instant::::now() + Self::RECEIVE_TI= MEOUT; >> + loop { >> + let remaining =3D deadline - Instant::::now(); >> + if remaining.is_negative() { >> + break Err(ETIMEDOUT); >> + } >> + match inner.receive_msg::(remaining) { >> + Ok(msg) =3D> break Ok(msg), >> + Err(ERANGE) =3D> continue, >> + Err(e) =3D> break Err(e), >> + } >> + } > > This block and the one from `send_command` are strictly identical - we > should factor them out. > > The right place for this seems to be a new method in `CmdqInner`: > > fn await_msg(&mut self) -> Result ... > > Then this `await_msg` simply becomes: > > self.inner.lock().await_msg() > > While `send_command` is simplified to: > > let mut inner =3D self.inner.lock(); > inner.send_command(bar, command)?; > inner.await_msg() Unless I misunderstand the GSP code, the unmatched message is not discarded= , but rather the caller returns from inner code, and drops the lock so other wait= ers of GSP message can have a chance to take the inner lock and receive the mes= sage so then get the non-matched message out of the way. So your suggestion woul= d cause `await_msg` to never complete in such cases? If my understanding of this is correct, then this code should just be moved= to the outer `receive_msg`, because all callers of it have the same loop and I think it's a wanted behaviour anyway. BTW, ERANGE is a very bad error code to mean "the message had a recognized = but non-matching function code". Best, Gary