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Subject: Re: [PATCH] iommu/amd: Fix extended features logging
From:   Joe Perches <joe@perches.com>
To:     John Ogness <john.ogness@linutronix.de>,
        Alexander Monakov <amonakov@ispras.ru>
Cc:     Paul Menzel <pmenzel@molgen.mpg.de>,
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Date:   Sun, 11 Apr 2021 14:08:14 -0700
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On Sun, 2021-04-11 at 21:52 +0200, John Ogness wrote:
> I'd rather fix dev_info callers to allow pr_cont and then fix any code
> that is using this workaround.

Assuming you mean all dev_<level>() uses, me too.

> And if the print maintainers agree it is OK to encourage
> pr_cont(LOGLEVEL "...") usage, then people should really start using
> that if the loglevel on those pieces is important.

I have no stong feeling about the use of pr_cont(<KERN_LEVEL>
as valuable or not.  I think it's just a trivial bit that
could be somewhat useful when interleaving occurs.

A somewhat better mechanism would be to have an explicit
cookie use like:

	cookie = printk_multipart_init(KERN_LEVEL, fmt, ...);
	while (<condition>)
		printk_multipart_cont(cookie, fmt, ...);
	printk_multipark_end(cookie, fmt, ...);

And separately, there should be a pr_debug_cont or equivalent.



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Subject: Re: [PATCH] iommu/amd: Fix extended features logging
From: Joe Perches <joe@perches.com>
To: John Ogness <john.ogness@linutronix.de>, Alexander Monakov
 <amonakov@ispras.ru>
Date: Sun, 11 Apr 2021 14:08:14 -0700
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On Sun, 2021-04-11 at 21:52 +0200, John Ogness wrote:
> I'd rather fix dev_info callers to allow pr_cont and then fix any code
> that is using this workaround.

Assuming you mean all dev_<level>() uses, me too.

> And if the print maintainers agree it is OK to encourage
> pr_cont(LOGLEVEL "...") usage, then people should really start using
> that if the loglevel on those pieces is important.

I have no stong feeling about the use of pr_cont(<KERN_LEVEL>
as valuable or not.  I think it's just a trivial bit that
could be somewhat useful when interleaving occurs.

A somewhat better mechanism would be to have an explicit
cookie use like:

	cookie = printk_multipart_init(KERN_LEVEL, fmt, ...);
	while (<condition>)
		printk_multipart_cont(cookie, fmt, ...);
	printk_multipark_end(cookie, fmt, ...);

And separately, there should be a pr_debug_cont or equivalent.


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