Re: [PATCH v5 2/4] printk/nmi: warn when some message has been lost in NMI context

From: Russell King - ARM Linux
Date: Wed Apr 27 2016 - 05:35:12 EST


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...

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