Linux-rt-users archive on lore.kernel.org
 help / color / Atom feed
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Marouen Ghodhbane <marouen.ghodhbane@nxp.com>
Cc: "linux-rt-users@vger.kernel.org" <linux-rt-users@vger.kernel.org>
Subject: Re: complete_all warning with 3 waiters
Date: Tue, 17 Mar 2020 13:08:17 +0100
Message-ID: <20200317120817.zm3a2zr4bsvpcbsn@linutronix.de> (raw)
In-Reply-To: <DB3PR0402MB3708A4D019B384FE29CBDD96F6FC0@DB3PR0402MB3708.eurprd04.prod.outlook.com>

On 2020-03-11 16:32:03 [+0000], Marouen Ghodhbane wrote:
> Hello everyone,
Hi,

> In fact, there is 3 sdma controller devices on the target pointing to
> the same firmware file and the imx-sdma driver is requesting the
> firmware asynchronously with request_firmware_nowait(). The
> request_firmware API in linux is making all waiters, requesting the
> same firmware file, wait on the same completion which triggers this
> warning.

This looks like something that happens at boot / hardware setup time and
not while the system is running "production". Thanks for the feedback.

> Any idea/suggestion is definitely appreciated

I've been interested in cases which can stack up beyond 2 and can be
triggered by users because these may influence the RT workload.
The pm-case has been filtered out because nobody should do RT a workload
while PM is going up and down. The report I got was in the init-phase of
crypto which does not trigger usually and shouldn't trigger at run-time
once everything is set up.
Feel free to raise the bar here to avoid the warning in your case here.
I'm currently thinking about removing the warning due to lack of new
cases.

> Best Regards,
> Marouen.

Sebastian

  parent reply index

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-11 16:32 Marouen Ghodhbane
2020-03-12  8:10 ` Daniel Wagner
2020-03-17 12:08 ` Sebastian Andrzej Siewior [this message]
2020-03-17 23:51   ` [EXT] " Marouen Ghodhbane

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=20200317120817.zm3a2zr4bsvpcbsn@linutronix.de \
    --to=bigeasy@linutronix.de \
    --cc=linux-rt-users@vger.kernel.org \
    --cc=marouen.ghodhbane@nxp.com \
    /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

Linux-rt-users archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-rt-users/0 linux-rt-users/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-rt-users linux-rt-users/ https://lore.kernel.org/linux-rt-users \
		linux-rt-users@vger.kernel.org
	public-inbox-index linux-rt-users

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-rt-users


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git