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Date: Wed, 25 Jul 2018 17:31:35 -0300
From: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
To: LEROY Christophe <christophe.leroy@c-s.fr>
Cc: linuxppc-dev@lists.ozlabs.org, "Tobin C . Harding" <me@tobin.cc>,
 Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>,
 Simon Guo <wei.guo.simon@gmail.com>, Paul Mackerras <paulus@samba.org>,
 Nicholas Piggin <npiggin@gmail.com>, Michael Neuling <mikey@neuling.org>,
 Michael Ellerman <mpe@ellerman.id.au>,
 "Eric W . Biederman" <ebiederm@xmission.com>,
 Cyril Bur <cyrilbur@gmail.com>,
 Benjamin Herrenschmidt <benh@kernel.crashing.org>,
 Balbir Singh <bsingharora@gmail.com>,
 Andrew Donnellan <andrew.donnellan@au1.ibm.com>,
 "Alastair D'Silva" <alastair@d-silva.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/7] powerpc/traps: Return early in show_signal_msg()
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Hi, Christophe.

On Wed, Jul 25, 2018 at 05:42:28PM +0200, LEROY Christophe wrote:
> Murilo Opsfelder Araujo <muriloo@linux.ibm.com> a écrit :
> 
> > Modify logic of show_signal_msg() to return early, if possible.  Replace
> > printk_ratelimited() by printk() and a default rate limit burst to limit
> > displaying unhandled signals messages.
> 
> Can you explain more the benefits of this change ?

Mainly is to improve readability of the function.

The conditions to display the message were coupled together in one
single `if` statement.

Besides that, patch 5/7 adds a call to print_vma_addr(), which is not
aware of any rate limit - it simply calls printk().

So splitting out the rate limit check outside show_signal_msg() makes it
easier to the caller decide if it wants to respect a printk rate limit
or not.

Cheers
Murilo