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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Sep 2025 19:26:14.2611 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 767e9faa-efe4-4432-4ba2-08ddff8e0e1a X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CY4PEPF0000EDD7.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY8PR12MB7706 On 9/29/25 9:45 AM, Mathieu Poirier wrote: > On Sun, Sep 28, 2025 at 03:56:41PM +0800, Peng Fan wrote: >> Hi, >> >> On Fri, Sep 26, 2025 at 10:40:09AM -0500, Tanmay Shah wrote: >>>>> --- >>>>> drivers/mailbox/mailbox.c | 24 ++++++++++++++++++++++++ >>>>> drivers/remoteproc/xlnx_r5_remoteproc.c | 4 ++++ >>>>> include/linux/mailbox_client.h | 1 + >>>> >>>> The mailbox and remoteproc should be separated. >>>> >>> >>> Mailbox framework is introducing new API. I wanted the use case to be in the >>> same patch-set, otherwise we might see unused API warning. >> >> I mean two patches in one patchset. >> > > Agreed > Okay. >>> >>> Hence, both in the same patch makes more sense. If maintainers prefer, I will >>> separate them. >>> >>>>> 3 files changed, 29 insertions(+) >>>>> >>>>> diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c >>>>> index 5cd8ae222073..7afdb2c9006d 100644 >>>>> --- a/drivers/mailbox/mailbox.c >>>>> +++ b/drivers/mailbox/mailbox.c >>>>> @@ -217,6 +217,30 @@ bool mbox_client_peek_data(struct mbox_chan *chan) >>>>> } >>>>> EXPORT_SYMBOL_GPL(mbox_client_peek_data); >>>>> >>>>> +/** >>>>> + * mbox_queue_full - check if mailbox queue is full or not >>>>> + * @chan: Mailbox channel assigned to this client. >>>>> + * >>>>> + * Clients can choose not to send new msg if mbox queue is full. >>>>> + * >>>>> + * Return: true if queue is full else false. < 0 for error >>>>> + */ >>>>> +int mbox_queue_full(struct mbox_chan *chan) >>>>> +{ >>>>> + unsigned long flags; >>>>> + int res; >>>>> + >>>>> + if (!chan) >>>>> + return -EINVAL; >>>>> + >>>>> + spin_lock_irqsave(&chan->lock, flags); >>>> >>>> Use scoped_guard. >>> >>> Other APIs use spin_lock_irqsave. Probably scoped_guard should be introduced >>> in a different patch for all APIs in the mailbox. >> >> Your code base seems not up to date. >> > > Agreed > Okay. I was referring to different branch when I referred other API in the mailbox framework. Sure, I will use scoped_guard. >>> >>>> >>>>> + res = (chan->msg_count == (MBOX_TX_QUEUE_LEN - 1)); > > Please have a look at this condition again - the implementation of > addr_to_rbuf() [1] is checking for space differently. > > [1]. https://elixir.bootlin.com/linux/v6.17/source/drivers/mailbox/mailbox.c#L32 > >>>>> + spin_unlock_irqrestore(&chan->lock, flags); >>>>> + >>>>> + return res; >>>>> +} >>>>> +EXPORT_SYMBOL_GPL(mbox_queue_full); >>>> >>>> add_to_rbuf is able to return ENOBUFS when call mbox_send_message. >>>> Does checking mbox_send_message return value works for you? >>>> >>> >>> That is the problem. mbox_send_message uses add_to_rbuf and fails. But during >>> failure, it prints warning message: >>> >>> dev_err(chan->mbox->dev, "Try increasing MBOX_TX_QUEUE_LEN\n"); >>> >>> In some cases there are lot of such messages on terminal. Functionally >>> nothing is wrong and everything is working but user keeps getting false >>> positive warning about increasing mbox tx queue length. That is why we need >>> API to check if mbox queue length is full or not before doing >>> mbox_send_message. Not all clients need to use it, but some cane make use of >>> it. >> >> I think check whether mbox_send_message returns -ENOBUFS or not should >> work for you. If the "Try increasing MBOX_TX_QUEUE_LEN" message >> bothers you, it could be update to dev_dbg per my understanding. >> > > This new API is trying to avoid calling mbox_send_message(), no checking if it > succeeded or not. Moving dev_err() nto dev_dbg() is also the wrong approach. > Correct. >> Regards, >> Peng >> >>> >>> >>>>> + >>>>> /** >>>>> * mbox_send_message - For client to submit a message to be >>>>> * sent to the remote. >>>> >>>> Regards >>>> Peng >>>