Re: [PATCH 03/18] printk: Convert pr_fmt from blank define to KBUILD_MODNAME

From: Steven Rostedt
Date: Thu May 10 2018 - 12:28:51 EST


On Thu, 10 May 2018 08:45:29 -0700
Joe Perches <joe@xxxxxxxxxxx> wrote:

> There are more than 1000 uses of #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> Make that the default define so these uses can be removed later via script.
>
> Signed-off-by: Joe Perches <joe@xxxxxxxxxxx>
> ---
> include/linux/printk.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/linux/printk.h b/include/linux/printk.h
> index 6d7e800affd8..172dce24e1b6 100644
> --- a/include/linux/printk.h
> +++ b/include/linux/printk.h
> @@ -285,7 +285,7 @@ static inline void printk_safe_flush_on_panic(void)
> extern int kptr_restrict;
>
> #ifndef pr_fmt
> -#define pr_fmt(fmt) fmt
> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> #endif

Interesting change. The ring buffer test went from:

[ 12.778404] CPU 0:
[ 12.780488] events: 1596368
[ 12.784841] dropped bytes: 0
[ 12.788682] alloced bytes: 124382988
[ 12.793206] written bytes: 121852123
[ 12.797711] biggest event: 263
[ 12.801706] smallest event: 4
[ 12.809384] read events: 12106
[ 12.813464] lost events: 1584262
[ 12.817709] total events: 1596368
[ 12.821951] recorded len bytes: 975776
[ 12.826107] recorded size bytes: 955733
[ 12.830263] With dropped events, record len and size may not match
[ 12.830263] alloced and written from above

to

[ 12.779526] ring_buffer: CPU 0:
[ 12.782753] ring_buffer: events: 1812797
[ 12.788223] ring_buffer: dropped bytes: 0
[ 12.793179] ring_buffer: alloced bytes: 142291920
[ 12.798815] ring_buffer: written bytes: 139410962
[ 12.804446] ring_buffer: biggest event: 211
[ 12.809558] ring_buffer: smallest event: 4
[ 12.818571] ring_buffer: read events: 13099
[ 12.824929] ring_buffer: lost events: 1799698
[ 12.830293] ring_buffer: total events: 1812797
[ 12.835657] ring_buffer: recorded len bytes: 974336
[ 12.840935] ring_buffer: recorded size bytes: 953514
[ 12.846218] ring_buffer: With dropped events, record len and size may not match
[ 12.846218] alloced and written from above

I'm fine with it.

Acked-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>

-- Steve