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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: dZcUC7EW/ZwV0c56zJlfMUksElrKqXRtQyGwEiX/d1ZCM0O9ZGq2VtwjDR+zzYknukTwFqicQwLyGoveU9f6LEylacURErekiokvfzv20UG9AUGlDmy1Ivn4KIhmeKa7MuzRqABDJBtlYtgjszQ+nAV70m2h+t3/4ipmDRW+xvE2Y9XHmi74JTRD4CzQh0/eWheAVa5cM9iz8xMgQugrrjZ9azWcMyxgSxlyiJ21UVfH+NRNxKd715Ayot0FuX5nRq/2wty5vFKX/MHrOOnPmJ4F1v0lK6On8tAALcHLGHQeT5oOlNR856CZ6nrxhoPwy6lDWYTr+XuXIQmHs2sxZD3n+QoknpTSpp9nTooaVzbKUqO29WYQcil0BaXpIOWK3vFIjBTiDW7O/vM/CqhzcOPMn2qrc9WkwNGyuzku0N2O+2EU2I8uqX/QX3et8M8K X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Mar 2026 15:09:29.9970 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 89fb2299-fa44-4d0a-94f7-08de7a0008e0 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: MWH0EPF000C6188.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR12MB8174 On 2/26/2026 9:53 PM, Bjorn Andersson wrote: > On Mon, Feb 23, 2026 at 06:35:16PM -0600, Jassi Brar wrote: >> On Mon, Feb 23, 2026 at 9:29 AM Bjorn Andersson wrote: >>> >>> On Mon, Feb 09, 2026 at 05:44:30PM -0600, jassisinghbrar@gmail.com wrote: >>>> From: Jassi Brar >>>> >>>> Clients sometimes need to know whether the mailbox TX queue has room >>>> before posting a new message. >>> >>> This is rather vague, could you be more specific? >>> >>>> Rather than exposing internal queue state >>>> through a struct field, provide a proper accessor function that returns >>>> the number of available slots for a given channel. >>>> >>>> This lets clients choose to back off when the queue is full instead of >>>> hitting the -ENOBUFS error path and the misleading "Try increasing >>>> MBOX_TX_QUEUE_LEN" warning. >>>> >>> >>> In the event that we're using the mailbox framework as a doorbell, I >>> presume that the queue is full of duplicate rings already - so backing >>> off it perfectly fine. >>> >>> But in the case where the client actually uses the interface to convey >>> data, what is the expected way for the client to know when to make >>> another attempt? >>> >> Whatever the client is currently using. It just backs off for another >> such signal when mbox_chan_tx_slots_available() returns 0. >> If a client submits periodically, it will back off for another period. >> If a client submits upon receiving ack packet for last submission, it >> will back off until it gets another ack packet. >> > > Thanks for clarifying. > Hi Jassi, What is the next step for this patch? When it is expected to merge? Thank You, Tanmay > Regards, > Bjorn > >> Cheers! >> Jassi