Re: [PATCH 1/3] rbtree_test: use pr_info for module prefix inmessages

From: Joe Perches
Date: Mon Mar 18 2013 - 19:44:30 EST

On Mon, 2013-03-18 at 16:20 -0700, Davidlohr Bueso wrote:
> This provides nicer message output. Since it seems more appropriate
> for the nature of this module, also use KERN_INFO instead of other
> levels.
> diff --git a/lib/rbtree_test.c b/lib/rbtree_test.c
> @@ -153,7 +156,7 @@ static int rbtree_test_init(void)
> int i, j;
> cycles_t time1, time2, time;
> - printk(KERN_ALERT "rbtree testing");
> + pr_info("rbtree testing");
> prandom_seed_state(&rnd, 3141592653589793238ULL);
> init();
> @@ -171,7 +174,7 @@ static int rbtree_test_init(void)
> time = time2 - time1;
> time = div_u64(time, PERF_LOOPS);
> - printk(" -> %llu cycles\n", (unsigned long long)time);
> + pr_info(" -> %llu cycles\n", (unsigned long long)time);

You change the output here by more than just adding a prefix.

The first printk didn't have a newline.

The old code would print:

"rbtree testing -> <foo> cycles"

The new code prints:

"rbtree_test: rbtree testing"
"rbtree_test: -> <foo> cycles"

btw: each pr_info should have a newline termination
or be followed by a some number of pr_cont/printk with
the last one having a terminating newline.

The first pr_info here doesn't have a newline
so it's possible (though unlikely) that another
thread could have its output appended/interleaved
on the same line.

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