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Message-ID: <a9e2f6b65d4c098ab027ea849120d3cf61858e67.camel@perches.com>
Subject: Re: [PATCH] xtensa: improve stack dumping
From:   Joe Perches <joe@perches.com>
To:     Max Filippov <jcmvbkbc@gmail.com>, linux-xtensa@linux-xtensa.org
Cc:     Chris Zankel <chris@zankel.net>, linux-kernel@vger.kernel.org,
        Dmitry Safonov <dima@arista.com>,
        Petr Mladek <pmladek@suse.com>
Date:   Wed, 06 Nov 2019 14:33:55 -0800
In-Reply-To: <20191106181617.1832-1-jcmvbkbc@gmail.com>
References: <20191106181617.1832-1-jcmvbkbc@gmail.com>
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On Wed, 2019-11-06 at 10:16 -0800, Max Filippov wrote:
> Collect whole stack dump lines in a buffer and print the whole buffer
> when it's ready with pr_info instead of pr_cont. This makes stack dump
> lines consistent in SMP case and relies less on pr_cont/printk
> differences related to timestamps.
> Make size of stack dump configurable.
> Drop extra newline output in show_trace as its output format does not
> depend on CONFIG_KALLSYMS.
[]
> diff --git a/arch/xtensa/kernel/traps.c b/arch/xtensa/kernel/traps.c
[]
> @@ -512,10 +510,12 @@ void show_stack(struct task_struct *task, unsigned long *sp)
>  	for (i = 0; i < kstack_depth_to_print; i++) {
>  		if (kstack_end(sp))
>  			break;
> -		pr_cont(" %08lx", *sp++);
> +		sprintf(buf + (i % 8) * 9, " %08lx", *sp++);
>  		if (i % 8 == 7)
> -			pr_cont("\n");
> +			pr_info("%s\n", buf);
>  	}
> +	if (i % 8)
> +		pr_info("%s\n", buf);

Could this be done using hex_dump_to_buffer
by precalculating kstack_end ?