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Date: Wed, 27 Apr 2016 10:34:38 +0100
From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Petr Mladek <pmladek@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
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Subject: Re: [PATCH v5 2/4] printk/nmi: warn when some message has been lost
 in NMI context
Message-ID: <20160427093438.GK19428@n2100.arm.linux.org.uk>
References: <1461239325-22779-1-git-send-email-pmladek@suse.com>
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On Thu, Apr 21, 2016 at 01:48:43PM +0200, Petr Mladek wrote:
> @@ -64,8 +65,10 @@ static int vprintk_nmi(const char *fmt, va_list args)
>  again:
>  	len = atomic_read(&s->len);
>  
> -	if (len >= sizeof(s->buffer))
> +	if (len >= sizeof(s->buffer)) {
> +		atomic_inc(&nmi_message_lost);

This should be fine - I think its reasonable to expect that no one is
using a spinlock implementation for their atomic ops for this...

-- 
RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/
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