[PATCH v2] ttyprintk: make the printk log level configurable

[PATCH v2] ttyprintk: make the printk log level configurable

[Peter Korsgaard]

For some use cases it is handy to use a different printk log level than the
default (info) for the messages written to ttyprintk, so add a Kconfig
option similar to what we have for default console loglevel.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
---
Changes since v1:
- Leave [U] prefix in printk invocation and drop space before it as
  suggested by Joe Perces.

 drivers/char/Kconfig     | 8 ++++++++
 drivers/char/ttyprintk.c | 4 +++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index ce277ee0a28a..14a7f023f20b 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -66,6 +66,14 @@ config TTY_PRINTK
 
 	  If unsure, say N.
 
+config TTY_PRINTK_LEVEL
+	depends on TTY_PRINTK
+	int "ttyprintk log level (1-7)"
+	range 1 7
+	default "6"
+	help
+	  Printk log level to use for ttyprintk messages.
+
 config PRINTER
 	tristate "Parallel printer support"
 	depends on PARPORT
diff --git a/drivers/char/ttyprintk.c b/drivers/char/ttyprintk.c
index 67549ce88cc9..88808dbba486 100644
--- a/drivers/char/ttyprintk.c
+++ b/drivers/char/ttyprintk.c
@@ -37,6 +37,8 @@ static struct ttyprintk_port tpk_port;
  */
 #define TPK_STR_SIZE 508 /* should be bigger then max expected line length */
 #define TPK_MAX_ROOM 4096 /* we could assume 4K for instance */
+#define TPK_PREFIX KERN_SOH __stringify(CONFIG_TTY_PRINTK_LEVEL)
+
 static int tpk_curr;
 
 static char tpk_buffer[TPK_STR_SIZE + 4];
@@ -45,7 +47,7 @@ static void tpk_flush(void)
 {
 	if (tpk_curr > 0) {
 		tpk_buffer[tpk_curr] = '\0';
-		pr_info("[U] %s\n", tpk_buffer);
+		printk(TPK_PREFIX "[U] %s\n", tpk_buffer);
 		tpk_curr = 0;
 	}
 }
-- 
2.11.0

Re: [PATCH v2] ttyprintk: make the printk log level configurable

[Peter Korsgaard]

On Fri, Sep 7, 2018 at 10:18 AM Peter Korsgaard <peter@korsgaard.com> wrote:
>
> For some use cases it is handy to use a different printk log level than the
> default (info) for the messages written to ttyprintk, so add a Kconfig
> option similar to what we have for default console loglevel.
>
> Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
> ---
> Changes since v1:
> - Leave [U] prefix in printk invocation and drop space before it as
>   suggested by Joe Perces.

Ping? Joe, if you are happy with v2, then it would be great if you could ack it.

Thanks.

>  drivers/char/Kconfig     | 8 ++++++++
>  drivers/char/ttyprintk.c | 4 +++-
>  2 files changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
> index ce277ee0a28a..14a7f023f20b 100644
> --- a/drivers/char/Kconfig
> +++ b/drivers/char/Kconfig
> @@ -66,6 +66,14 @@ config TTY_PRINTK
>
>           If unsure, say N.
>
> +config TTY_PRINTK_LEVEL
> +       depends on TTY_PRINTK
> +       int "ttyprintk log level (1-7)"
> +       range 1 7
> +       default "6"
> +       help
> +         Printk log level to use for ttyprintk messages.
> +
>  config PRINTER
>         tristate "Parallel printer support"
>         depends on PARPORT
> diff --git a/drivers/char/ttyprintk.c b/drivers/char/ttyprintk.c
> index 67549ce88cc9..88808dbba486 100644
> --- a/drivers/char/ttyprintk.c
> +++ b/drivers/char/ttyprintk.c
> @@ -37,6 +37,8 @@ static struct ttyprintk_port tpk_port;
>   */
>  #define TPK_STR_SIZE 508 /* should be bigger then max expected line length */
>  #define TPK_MAX_ROOM 4096 /* we could assume 4K for instance */
> +#define TPK_PREFIX KERN_SOH __stringify(CONFIG_TTY_PRINTK_LEVEL)
> +
>  static int tpk_curr;
>
>  static char tpk_buffer[TPK_STR_SIZE + 4];
> @@ -45,7 +47,7 @@ static void tpk_flush(void)
>  {
>         if (tpk_curr > 0) {
>                 tpk_buffer[tpk_curr] = '\0';
> -               pr_info("[U] %s\n", tpk_buffer);
> +               printk(TPK_PREFIX "[U] %s\n", tpk_buffer);
>                 tpk_curr = 0;
>         }
>  }
> --
> 2.11.0
>


-- 
Bye, Peter Korsgaard