All of lore.kernel.org
 help / color / mirror / Atom feed
From: Corentin Labbe <clabbe.montjoie@gmail.com>
To: Horia Geanta <horia.geanta@nxp.com>
Cc: "davem@davemloft.net" <davem@davemloft.net>,
	"herbert@gondor.apana.org.au" <herbert@gondor.apana.org.au>,
	"mripard@kernel.org" <mripard@kernel.org>,
	"wens@csie.org" <wens@csie.org>,
	Iuliana Prodan <iuliana.prodan@nxp.com>,
	"linux-sunxi@googlegroups.com" <linux-sunxi@googlegroups.com>,
	"linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/9] crypto: engine: workqueue can only be processed one by one
Date: Tue, 28 Jan 2020 16:58:00 +0100	[thread overview]
Message-ID: <20200128155800.GB17295@Red> (raw)
In-Reply-To: <VI1PR0402MB3485B787EA6BCDD5A5600BAA980A0@VI1PR0402MB3485.eurprd04.prod.outlook.com>

On Tue, Jan 28, 2020 at 03:50:14PM +0000, Horia Geanta wrote:
> On 1/22/2020 12:46 PM, Corentin Labbe wrote:
> > Some bykeshedding are unnecessary since a workqueue can only be executed
> > one by one.
> > This behaviour is documented in:
> > - kernel/kthread.c: comment of kthread_worker_fn()
> > - Documentation/core-api/workqueue.rst: the functions associated with the work items one after the other
> [...]
> > @@ -73,16 +73,6 @@ 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)
> > -		goto out;
> > -
> This check is here for a good reason, namely because crypto engine
> cannot currently handle multiple crypto requests being in "flight"
> in parallel.
> 
> More exactly, if this check is removed the following sequence could occur:
> crypto_pump_work() -> crypto_pump_requests() -> .do_one_request(areq1)
> crypto_pump_work() -> crypto_pump_requests() -> .do_one_request(areq2)
> crypto_finalize_request(areq1)
> crypto_finalize_request(areq2)
> 

As explained in the commitlog, crypto_pump_work() cannot be ran twice.

Regards

WARNING: multiple messages have this Message-ID (diff)
From: Corentin Labbe <clabbe.montjoie@gmail.com>
To: Horia Geanta <horia.geanta@nxp.com>
Cc: "herbert@gondor.apana.org.au" <herbert@gondor.apana.org.au>,
	Iuliana Prodan <iuliana.prodan@nxp.com>,
	"linux-sunxi@googlegroups.com" <linux-sunxi@googlegroups.com>,
	"mripard@kernel.org" <mripard@kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"wens@csie.org" <wens@csie.org>,
	"linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>,
	"davem@davemloft.net" <davem@davemloft.net>,
	"linux-arm-kernel@lists.infradead.org"
	<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH 1/9] crypto: engine: workqueue can only be processed one by one
Date: Tue, 28 Jan 2020 16:58:00 +0100	[thread overview]
Message-ID: <20200128155800.GB17295@Red> (raw)
In-Reply-To: <VI1PR0402MB3485B787EA6BCDD5A5600BAA980A0@VI1PR0402MB3485.eurprd04.prod.outlook.com>

On Tue, Jan 28, 2020 at 03:50:14PM +0000, Horia Geanta wrote:
> On 1/22/2020 12:46 PM, Corentin Labbe wrote:
> > Some bykeshedding are unnecessary since a workqueue can only be executed
> > one by one.
> > This behaviour is documented in:
> > - kernel/kthread.c: comment of kthread_worker_fn()
> > - Documentation/core-api/workqueue.rst: the functions associated with the work items one after the other
> [...]
> > @@ -73,16 +73,6 @@ 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)
> > -		goto out;
> > -
> This check is here for a good reason, namely because crypto engine
> cannot currently handle multiple crypto requests being in "flight"
> in parallel.
> 
> More exactly, if this check is removed the following sequence could occur:
> crypto_pump_work() -> crypto_pump_requests() -> .do_one_request(areq1)
> crypto_pump_work() -> crypto_pump_requests() -> .do_one_request(areq2)
> crypto_finalize_request(areq1)
> crypto_finalize_request(areq2)
> 

As explained in the commitlog, crypto_pump_work() cannot be ran twice.

Regards

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2020-01-28 15:58 UTC|newest]

Thread overview: 31+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-22 10:45 [PATCH 0/9] crypto: engine: permit to handle multiple requests Corentin Labbe
2020-01-22 10:45 ` Corentin Labbe
2020-01-22 10:45 ` [PATCH 1/9] crypto: engine: workqueue can only be processed one by one Corentin Labbe
2020-01-22 10:45   ` Corentin Labbe
2020-01-28 15:50   ` Horia Geanta
2020-01-28 15:58     ` Corentin Labbe [this message]
2020-01-28 15:58       ` Corentin Labbe
2020-01-28 16:55       ` Corentin Labbe
2020-01-28 16:55         ` Corentin Labbe
2020-01-22 10:45 ` [PATCH 2/9] crypto: engine: get rid of cur_req_prepared Corentin Labbe
2020-01-22 10:45   ` Corentin Labbe
2020-01-22 10:45 ` [PATCH 3/9] crypto: engine: get rid of cur_req Corentin Labbe
2020-01-22 10:45   ` Corentin Labbe
2020-01-22 10:45 ` [PATCH 4/9] crypto: engine: permit to choose queue length Corentin Labbe
2020-01-22 10:45   ` Corentin Labbe
2020-01-22 10:45 ` [PATCH 5/9] crypto: engine: add enqueue_request/can_do_more Corentin Labbe
2020-01-22 10:45   ` Corentin Labbe
2020-01-27 22:58   ` Iuliana Prodan
2020-01-27 22:58     ` Iuliana Prodan
2020-01-28  8:40     ` Corentin Labbe
2020-01-28  8:40       ` Corentin Labbe
2020-01-28 11:00       ` Iuliana Prodan
2020-01-28 11:00         ` Iuliana Prodan
2020-01-22 10:45 ` [PATCH 6/9] crypto: sun8i-ce: move iv data to request context Corentin Labbe
2020-01-22 10:45   ` Corentin Labbe
2020-01-22 10:45 ` [PATCH 7/9] crypto: sun8i-ce: increase task list size Corentin Labbe
2020-01-22 10:45   ` Corentin Labbe
2020-01-22 10:45 ` [PATCH 8/9] crypto: sun8i-ce: split into prepare/run/unprepare Corentin Labbe
2020-01-22 10:45   ` Corentin Labbe
2020-01-22 10:45 ` [PATCH 9/9] crypto: sun8i-ce: permit to batch requests Corentin Labbe
2020-01-22 10:45   ` Corentin Labbe

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200128155800.GB17295@Red \
    --to=clabbe.montjoie@gmail.com \
    --cc=davem@davemloft.net \
    --cc=herbert@gondor.apana.org.au \
    --cc=horia.geanta@nxp.com \
    --cc=iuliana.prodan@nxp.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-crypto@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-sunxi@googlegroups.com \
    --cc=mripard@kernel.org \
    --cc=wens@csie.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.