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Message-ID: <1447666040.2191.3.camel@ellerman.id.au>
Subject: Re: [PATCH 1/5] powerpc: Print MSR TM bits in oops message
From: Michael Ellerman <mpe@ellerman.id.au>
To: Michael Neuling <mikey@neuling.org>, benh@kernel.crashing.org
Cc: sam.bobroff@au1.ibm.com, linuxppc-dev@ozlabs.org, paulus@samba.org
Date: Mon, 16 Nov 2015 20:27:20 +1100
In-Reply-To: <1447390652-28355-1-git-send-email-mikey@neuling.org>
References: <1447390652-28355-1-git-send-email-mikey@neuling.org>
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On Fri, 2015-11-13 at 15:57 +1100, Michael Neuling wrote:

> Print the MSR TM bits in oops messages.  This appends them to the end
> like this:
>  MSR: 8000000502823031 <SF,VEC,VSX,FP,ME,IR,DR,LE,TM[TE]>
> 
> You get the TM[] only if at least one TM MSR bit is set.  Inside the
> TM[], E means Enabled (bit 32), S means Suspended (bit 33), and T
> means Transactional (bit 34)

Can you duplicate this into a comment in printtmbits() or on the bit
definitions, so that I don't have to look up the commit to find the
explanation.

> +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
> +static struct regbit msr_tm_bits[] = {
> +	{MSR_TS_T,	"T"},
> +	{MSR_TS_S,	"S"},
> +	{MSR_TM,	"E"},
> +	{0,		NULL}
> +};
> +static void printtmbits(unsigned long val)

I realise you followed the lead here with the naming, but can you call it
print_tm_bits() please. MY EYES!

> +{
> +	if (val & (MSR_TM | MSR_TS_S | MSR_TS_T)) {
> +		printk(",TM[");
> +		printbits(val, msr_tm_bits, "");
> +		printk("]");

I suspect all these individual printks are going to behave badly if we have
multiple cpus crashing simultaneously. But I won't make you fix that here. We
should look at it sometime though.

cheers