On Tue, Jan 21, 2020 at 02:20:27PM +0000, Iuliana Prodan wrote:
> On 1/21/2020 12:00 PM, Corentin Labbe wrote:
> > On Tue, Jan 21, 2020 at 01:32:29AM +0200, Iuliana Prodan wrote:
> >> Added support for executing multiple requests, in parallel,
> >> for crypto engine.
> >> A no_reqs is initialized and set in the new
> >> crypto_engine_alloc_init_and_set function.
> >> Here, is also set the maximum size for crypto-engine software
> >> queue (not hardcoded anymore).
> >> On crypto_pump_requests the no_reqs is increased, until the
> >> max_no_reqs is reached, and decreased on crypto_finalize_request,
> >> or on error path (in case a prepare_request or do_one_request
> >> operation was unsuccessful).
> >>
> >> Signed-off-by: Iuliana Prodan <iuliana.prodan@xxxxxxx>
> >> ---
> >> crypto/crypto_engine.c | 112 +++++++++++++++++++++++++++++++++---------------
> >> include/crypto/engine.h | 11 +++--
> >> 2 files changed, 84 insertions(+), 39 deletions(-)
> >>
> >> diff --git a/crypto/crypto_engine.c b/crypto/crypto_engine.c
> >> index eb029ff..5219141 100644
> >> --- a/crypto/crypto_engine.c
> >> +++ b/crypto/crypto_engine.c
> >> @@ -14,6 +14,7 @@
> >> #include "internal.h"
> >>
> >> #define CRYPTO_ENGINE_MAX_QLEN 10
> >> +#define CRYPTO_ENGINE_MAX_CONCURRENT_REQS 1
> >>
> >> /**
> >> * crypto_finalize_request - finalize one request if the request is done
> >> @@ -22,32 +23,27 @@
> >> * @err: error number
> >> */
> >> static void crypto_finalize_request(struct crypto_engine *engine,
> >> - struct crypto_async_request *req, int err)
> >> + struct crypto_async_request *req, int err)
> >> {
> >> unsigned long flags;
> >> - bool finalize_cur_req = false;
> >> + bool finalize_req = false;
> >> int ret;
> >> struct crypto_engine_ctx *enginectx;
> >>
> >> spin_lock_irqsave(&engine->queue_lock, flags);
> >> - if (engine->cur_req == req)
> >> - finalize_cur_req = true;
> >> + if (engine->no_reqs > 0) {
> >> + finalize_req = true;
> >> + engine->no_reqs--;
> >> + }
> >> spin_unlock_irqrestore(&engine->queue_lock, flags);
> >>
> >> - if (finalize_cur_req) {
> >> - enginectx = crypto_tfm_ctx(req->tfm);
> >> - if (engine->cur_req_prepared &&
> >> - enginectx->op.unprepare_request) {
> >> - ret = enginectx->op.unprepare_request(engine, req);
> >> - if (ret)
> >> - dev_err(engine->dev, "failed to unprepare request\n");
> >> - }
> >> - spin_lock_irqsave(&engine->queue_lock, flags);
> >> - engine->cur_req = NULL;
> >> - engine->cur_req_prepared = false;
> >> - spin_unlock_irqrestore(&engine->queue_lock, flags);
> >> + enginectx = crypto_tfm_ctx(req->tfm);
> >> + if (finalize_req && enginectx->op.prepare_request &&
> >> + enginectx->op.unprepare_request) {
> >> + ret = enginectx->op.unprepare_request(engine, req);
> >> + if (ret)
> >> + dev_err(engine->dev, "failed to unprepare request\n");
> >> }
> >> -
> >> req->complete(req, err);
> >>
> >> kthread_queue_work(engine->kworker, &engine->pump_requests);
> >> @@ -73,8 +69,8 @@ static void crypto_pump_requests(struct crypto_engine *engine,
> >>
> >> spin_lock_irqsave(&engine->queue_lock, flags);
> >>
> >> - /* Make sure we are not already running a request */
> >> - if (engine->cur_req)
> >> + /* Make sure we have space, for more requests to run */
> >> + if (engine->no_reqs >= engine->max_no_reqs)
> >> goto out;
> >>
> >> /* If another context is idling then defer */
> >> @@ -108,13 +104,16 @@ static void crypto_pump_requests(struct crypto_engine *engine,
> >> goto out;
> >> }
> >>
> >> +retry:
> >> /* Get the fist request from the engine queue to handle */
> >> backlog = crypto_get_backlog(&engine->queue);
> >> async_req = crypto_dequeue_request(&engine->queue);
> >> if (!async_req)
> >> goto out;
> >>
> >> - engine->cur_req = async_req;
> >> + /* Increase the number of concurrent requests that are in execution */
> >> + engine->no_reqs++;
> >> +
> >> if (backlog)
> >> backlog->complete(backlog, -EINPROGRESS);
> >>
> >> @@ -130,7 +129,7 @@ static void crypto_pump_requests(struct crypto_engine *engine,
> >> ret = engine->prepare_crypt_hardware(engine);
> >> if (ret) {
> >> dev_err(engine->dev, "failed to prepare crypt hardware\n");
> >> - goto req_err;
> >> + goto req_err_2;
> >> }
> >> }
> >>
> >> @@ -141,26 +140,45 @@ static void crypto_pump_requests(struct crypto_engine *engine,
> >> if (ret) {
> >> dev_err(engine->dev, "failed to prepare request: %d\n",
> >> ret);
> >> - goto req_err;
> >> + goto req_err_2;
> >> }
> >> - engine->cur_req_prepared = true;
> >> }
> >> if (!enginectx->op.do_one_request) {
> >> dev_err(engine->dev, "failed to do request\n");
> >> ret = -EINVAL;
> >> - goto req_err;
> >> + goto req_err_1;
> >> }
> >> +
> >> 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;
> >> + goto req_err_1;
> >> }
> >> - return;
> >> -
> >> -req_err:
> >> - crypto_finalize_request(engine, async_req, ret);
> >> - return;
> >>
> >> + /*
> >> + * If there is still space for concurrent requests,
> >> + * try and send a new one
> >> + */
> >> + spin_lock_irqsave(&engine->queue_lock, flags);
> >> + if (engine->no_reqs < engine->max_no_reqs)
> >> + goto retry;
> >
> > You should check if engine->queue.qlen > 0 before retry.
> >
> >> + goto out;
> >> +
> >> +req_err_1:
> >> + if (enginectx->op.unprepare_request) {
> >> + ret = enginectx->op.unprepare_request(engine, async_req);
> >> + if (ret)
> >> + dev_err(engine->dev, "failed to unprepare request\n");
> >> + }
> >> +req_err_2:
> >> + async_req->complete(async_req, ret);
> >> + spin_lock_irqsave(&engine->queue_lock, flags);
> >> + /*
> >> + * If unable to prepare or execute the request,
> >> + * decrease the number of concurrent requests
> >> + */
> >> + engine->no_reqs--;
> >> + goto retry;
> >
> > You should check if engine->queue.qlen > 0 before retry.
> >
> Here (and above) is not needed to check for qlen > 0, since on retry,
> first thing is tryin to dequeue an async_req from crypto-engine queue.
> In crypto_dequeue_request function is a check for qlen, that means than
> in pump_request will goto out.
>
> >> out:
> >> spin_unlock_irqrestore(&engine->queue_lock, flags);
> >> }
> >> @@ -386,15 +404,21 @@ int crypto_engine_stop(struct crypto_engine *engine)
> >> EXPORT_SYMBOL_GPL(crypto_engine_stop);
> >>
> >> /**
> >> - * crypto_engine_alloc_init - allocate crypto hardware engine structure and
> >> - * initialize it.
> >> + * crypto_engine_alloc_init_and_set - allocate crypto hardware engine structure
> >> + * and initialize it by setting the maximum number of entries in the software
> >> + * crypto-engine queue and the maximum number of concurrent requests that can
> >> + * be executed at once.
> >> * @dev: the device attached with one hardware engine
> >> * @rt: whether this queue is set to run as a realtime task
> >> + * @max_no_reqs: maximum number of request that can be executed in parallel
> >> + * @qlen: maximum size of the crypto-engine queue
> >> *
> >> * This must be called from context that can sleep.
> >> * Return: the crypto engine structure on success, else NULL.
> >> */
> >> -struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt)
> >> +struct crypto_engine *crypto_engine_alloc_init_and_set(struct device *dev,
> >> + bool rt, int max_no_reqs,
> >> + int qlen)
> >> {
> >> struct sched_param param = { .sched_priority = MAX_RT_PRIO / 2 };
> >> struct crypto_engine *engine;
> >> @@ -411,12 +435,13 @@ struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt)
> >> engine->running = false;
> >> engine->busy = false;
> >> engine->idling = false;
> >> - engine->cur_req_prepared = false;
> >> engine->priv_data = dev;
> >> snprintf(engine->name, sizeof(engine->name),
> >> "%s-engine", dev_name(dev));
> >> + engine->max_no_reqs = max_no_reqs;
> >> + engine->no_reqs = 0;
> >>
> >> - crypto_init_queue(&engine->queue, CRYPTO_ENGINE_MAX_QLEN);
> >> + crypto_init_queue(&engine->queue, qlen);
> >> spin_lock_init(&engine->queue_lock);
> >>
> >> engine->kworker = kthread_create_worker(0, "%s", engine->name);
> >> @@ -433,6 +458,23 @@ struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt)
> >>
> >> return engine;
> >> }
> >> +EXPORT_SYMBOL_GPL(crypto_engine_alloc_init_and_set);
> >> +
> >> +/**
> >> + * crypto_engine_alloc_init - allocate crypto hardware engine structure and
> >> + * initialize it.
> >> + * @dev: the device attached with one hardware engine
> >> + * @rt: whether this queue is set to run as a realtime task
> >> + *
> >> + * This must be called from context that can sleep.
> >> + * Return: the crypto engine structure on success, else NULL.
> >> + */
> >> +struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt)
> >> +{
> >> + return crypto_engine_alloc_init_and_set(dev, rt,
> >> + CRYPTO_ENGINE_MAX_CONCURRENT_REQS,
> >> + CRYPTO_ENGINE_MAX_QLEN);
> >> +}
> >> EXPORT_SYMBOL_GPL(crypto_engine_alloc_init);
> >>
> >> /**
> >> diff --git a/include/crypto/engine.h b/include/crypto/engine.h
> >> index e29cd67..5f9a6df 100644
> >> --- a/include/crypto/engine.h
> >> +++ b/include/crypto/engine.h
> >> @@ -24,7 +24,6 @@
> >> * @idling: the engine is entering idle state
> >> * @busy: request pump is busy
> >> * @running: the engine is on working
> >> - * @cur_req_prepared: current request is prepared
> >> * @list: link with the global crypto engine list
> >> * @queue_lock: spinlock to syncronise access to request queue
> >> * @queue: the crypto queue of the engine
> >> @@ -38,14 +37,14 @@
> >> * @kworker: kthread worker struct for request pump
> >> * @pump_requests: work struct for scheduling work to the request pump
> >> * @priv_data: the engine private data
> >> - * @cur_req: the current request which is on processing
> >> + * @max_no_reqs: maximum number of request which can be processed in parallel
> >> + * @no_reqs: current number of request which are processed in parallel
> >> */
> >> struct crypto_engine {
> >> char name[ENGINE_NAME_LEN];
> >> bool idling;
> >> bool busy;
> >> bool running;
> >> - bool cur_req_prepared;
> >>
> >> struct list_head list;
> >> spinlock_t queue_lock;
> >> @@ -61,7 +60,8 @@ struct crypto_engine {
> >> struct kthread_work pump_requests;
> >>
> >> void *priv_data;
> >> - struct crypto_async_request *cur_req;
> >> + int max_no_reqs;
> >> + int no_reqs;
> >> };
> >>
> >> /*
> >> @@ -102,6 +102,9 @@ void crypto_finalize_skcipher_request(struct crypto_engine *engine,
> >> int crypto_engine_start(struct crypto_engine *engine);
> >> int crypto_engine_stop(struct crypto_engine *engine);
> >> struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt);
> >> +struct crypto_engine *crypto_engine_alloc_init_and_set(struct device *dev,
> >> + bool rt, int max_no_reqs,
> >> + int qlen);
> >> int crypto_engine_exit(struct crypto_engine *engine);
> >>
> >> #endif /* _CRYPTO_ENGINE_H */
> >> --
> >> 2.1.0
> >>
> >
> > Hello
> >
> > In your model, who is running finalize_request() ?
> finalize_request() in CAAM, and in other drivers, is called on the _done
> callback (stm32, virtio and omap).
>
> > In caam it seems that you have a taskqueue dedicated for that but you cannot assume that all drivers will have this.
> > I think the crypto_engine should be sufficient by itself and does not need external thread/taskqueue.
> >
> > But in your case, it seems that you dont have the choice, since do_one_request does not "do" but simply enqueue the request in the "jobring".
> >
> But, do_one_request it shouldn't, necessary, execute the request. Is ok
> to enqueue it, since we have asynchronous requests. do_one_request is
> not blocking.
>
> > What about adding along prepare/do_one_request/unprepare a new enqueue()/can_do_more() function ?
> >
> > The stream will be:
> > retry:
> > optionnal prepare
> > optionnal enqueue
> > optionnal can_do_more() (goto retry)
> > optionnal do_one_request
> >
> > then
> > finalize()
> > optionnal unprepare
> >
>
> I'm planning to improve crypto-engine incrementally, so I'm taking one
> step at a time :)
> But I'm not sure if adding an enqueue operation is a good idea, since,
> my understanding, is that do_one_request is a non-blocking operation and
> it shouldn't execute the request.
do_one_request is a blocking operation on amlogic/sun8i-ce/sun8i-ss and the "documentation" is clear "@do_one_request: do encryption for current request".
But I agree that is a bit small for a documentation.
>
> IMO, the crypto-engine flow should be kept simple:
> 1. a request comes to hw -> this is doing transfer_request_to_engine;
> 2. CE enqueue the requests
> 3. on pump_requests:
> 3. a) optional prepare operation
> 3. b) sends the reqs to hw, by do_one_request operation. To wait for
> completion here it contradicts the asynchronous crypto API.
There are no contradiction, the call is asynchronous for the user of the API.
> do_one_request operation has a crypto_async_request type as argument.
> Note: Step 3. b) can be done several times, depending on size of hw queue.
> 4. in driver, when req is done:
> 4. a) optional unprepare operation
> 4. b) crypto_finalize_request is called
>
Since Herbert say the same thing than me:
"Instead, we should just let the driver tell us when it is ready to accept more requests."
Let me insist on my proposal, I have updated my serie, and it should handle your case and mine.
I will send it within minutes.
Regards
