Re: [PATCH] powerpc: Remove a few lines of oops output

[Michael Neuling <mikey@neuling.org>]

Anton Blanchard <anton@samba.org> wrote:

> 
> We waste quite a few lines in our oops output:
> 
> ...
> MSR: 8000000000009032 <SF,EE,ME,IR,DR,RI>  CR: 28044024  XER: 00000000
> SOFTE: 0
> CFAR: 0000000000009088
> DAR: 000000000000001c, DSISR: 40000000
> 
> GPR00: c0000000000c74f0 c00000037cc1b010 c000000000d2bb30 0000000000000000 
> ...
> 
> We can do a better job here and remove 3 lines:
> 
> MSR: 8000000000009032 <SF,EE,ME,IR,DR,RI>  CR: 28044024  XER: 00000000
> CFAR: 0000000000009088 DAR: 0000000000000010, DSISR: 40000000 SOFTE: 1 
> GPR00: c0000000000e3d10 c00000037cc2fda0 c000000000d2c3a8 0000000000000001 
> 
> Also move PACATMSCRATCH up, it doesn't really belong in the stack
> trace section.
> 

I like it.

> Signed-off-by: Anton Blanchard <anton@samba.org>
> ---
> 
> PACATMSCRATCH is a long and not very descriptive name. It appears to be
> an MSR so should it instead be called TM_MSR?

We also use it to store the stack point in the reclaim code.  

> Also, could we save a line and only print it if MSR_TM_ACTIVE()?

Yeah that would be fine.

Mikey

> 
> Index: b/arch/powerpc/kernel/process.c
> ===================================================================
> --- a/arch/powerpc/kernel/process.c
> +++ b/arch/powerpc/kernel/process.c
> @@ -858,17 +858,20 @@ void show_regs(struct pt_regs * regs)
>  	printk("MSR: "REG" ", regs->msr);
>  	printbits(regs->msr, msr_bits);
>  	printk("  CR: %08lx  XER: %08lx\n", regs->ccr, regs->xer);
> -#ifdef CONFIG_PPC64
> -	printk("SOFTE: %ld\n", regs->softe);
> -#endif
>  	trap = TRAP(regs);
>  	if ((regs->trap != 0xc00) && cpu_has_feature(CPU_FTR_CFAR))
> -		printk("CFAR: "REG"\n", regs->orig_gpr3);
> +		printk("CFAR: "REG" ", regs->orig_gpr3);
>  	if (trap == 0x200 || trap == 0x300 || trap == 0x600)
>  #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
> -		printk("DEAR: "REG", ESR: "REG"\n", regs->dar, regs->dsisr);
> +		printk("DEAR: "REG" ESR: "REG" ", regs->dar, regs->dsisr);
>  #else
> -		printk("DAR: "REG", DSISR: %08lx\n", regs->dar, regs->dsisr);
> +		printk("DAR: "REG" DSISR: %08lx ", regs->dar, regs->dsisr);
> +#endif
> +#ifdef CONFIG_PPC64
> +	printk("SOFTE: %ld ", regs->softe);
> +#endif
> +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
> +	printk("\nPACATMSCRATCH: %016llx ", get_paca()->tm_scratch);
>  #endif
>  
>  	for (i = 0;  i < 32;  i++) {
> @@ -887,9 +890,6 @@ void show_regs(struct pt_regs * regs)
>  	printk("NIP ["REG"] %pS\n", regs->nip, (void *)regs->nip);
>  	printk("LR ["REG"] %pS\n", regs->link, (void *)regs->link);
>  #endif
> -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
> -	printk("PACATMSCRATCH [%llx]\n", get_paca()->tm_scratch);
> -#endif
>  	show_stack(current, (unsigned long *) regs->gpr[1]);
>  	if (!user_mode(regs))
>  		show_instructions(regs);
>