On 3/12/2020 2:45 PM, Iuliana Prodan wrote: > On 3/12/2020 5:26 AM, Herbert Xu wrote: >> On Mon, Mar 09, 2020 at 12:51:32AM +0200, Iuliana Prodan wrote: >>> >>> ret = enginectx->op.do_one_request(engine, async_req); >>> - if (ret) { >>> - dev_err(engine->dev, "Failed to do one request from queue: %d\n", ret); >>> - goto req_err; >>> + can_enq_more = ret; >>> + if (can_enq_more < 0) { >>> + dev_err(engine->dev, "Failed to do one request from queue: %d\n", >>> + ret); >>> + goto req_err_1; >>> + } >> >> So this now includes the case of the hardware queue being full >> and the request needs to be queued until space opens up again. >> In this case, we should not do dev_err. So you need to be able >> to distinguish between the hardware queue being full vs. a real >> fatal error on the request (e.g., out-of-memory or some hardware >> failure). >> > There are two aspects here: > - if all requests go through crypto-engine, and, in this case, if there > is no space in hw queue, do_one_req returns 0, and actually there will > be no case of do_one_request() < 0; > - if there are other requests (non crypto API) that go to hw for > execution (in CAAM we have split key or RNG) those might occupy the hw > queue, after crypto-engine returns that it still has space. This case > wasn't supported before my modifications and neither with these patches. > This use-case can be solved by retrying to send the request to hw - > enqueue it back to crypto-engine, in the head of the queue (to keep the > order, and send it again to hw). > I've tried this, but it implies modifications in all drivers. For > example, a driver, in case of error, it frees the resources of the > request. So, will need to map again a request. > I believe this recovery mechanism should be handled in other patch (series). Herbert, what is your proposal to move forward? Thanks, Iulia