Re: [PATCH] xen: Rework WARN_ON() to return whether a warning was triggered

From: Julien Grall <julien@xen.org>
To: "Jürgen Groß" <jgross@suse.com>, xen-devel@lists.xenproject.org
Cc: bertrand.marquis@arm.com, Rahul.Singh@arm.com,
	Julien Grall <jgrall@amazon.com>,
	Andrew Cooper <andrew.cooper3@citrix.com>,
	George Dunlap <george.dunlap@citrix.com>,
	Ian Jackson <iwj@xenproject.org>, Jan Beulich <jbeulich@suse.com>,
	Stefano Stabellini <sstabellini@kernel.org>, Wei Liu <wl@xen.org>
Subject: Re: [PATCH] xen: Rework WARN_ON() to return whether a warning was triggered
Date: Tue, 15 Dec 2020 13:11:40 +0000	[thread overview]
Message-ID: <cbae7c17-829e-f48f-3a6a-7fee489711c2@xen.org> (raw)
In-Reply-To: <c45407e5-3173-4f0d-453b-1a01969b667c@suse.com>

Hi Juergen,

On 15/12/2020 11:31, Jürgen Groß wrote:
> On 15.12.20 12:26, Julien Grall wrote:
>> From: Julien Grall <jgrall@amazon.com>
>>
>> So far, our implementation of WARN_ON() cannot be used in the following
>> situation:
>>
>> if ( WARN_ON() )
>>      ...
>>
>> This is because the WARN_ON() doesn't return whether a warning. Such
> 
> ... warning has been triggered.

I will add it.

> 
>> construction can be handy to have if you have to print more information
>> and now the stack track.
> 
> Sorry, I'm not able to parse that sentence.

Urgh :/. How about the following commit message:

"So far, our implementation of WARN_ON() cannot be used in the following 
situation:

if ( WARN_ON() )
   ...

This is because WARN_ON() doesn't return whether a warning has been 
triggered. Such construciton can be handy if you want to print more 
information and also dump the stack trace.

Therefore, rework the WARN_ON() implementation to return whether a 
warning was triggered. The idea was borrowed from Linux".

Cheers,

-- 
Julien Grall