2018-08-21 18:05:59

by Peter Korsgaard

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

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 <[email protected]>
---
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..22fbd483b5dc 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) " [U]"
+
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 " %s\n", tpk_buffer);
tpk_curr = 0;
}
}
--
2.11.0

2018-09-07 07:52:18

by Peter Korsgaard

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

On Tue, Aug 21, 2018 at 7:28 PM Peter Korsgaard <[email protected]> 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.

Ping? Feedback, comments?

> 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..22fbd483b5dc 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) " [U]"
> +
> 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 " %s\n", tpk_buffer);
> tpk_curr = 0;
> }
> }
> --
> 2.11.0
>

--
Bye, Peter Korsgaard

2018-09-07 08:04:39

by Joe Perches

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

On Fri, 2018-09-07 at 09:50 +0200, Peter Korsgaard wrote:
> On Tue, Aug 21, 2018 at 7:28 PM Peter Korsgaard <[email protected]> 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.
>
> Ping? Feedback, comments?

I think it is moving "[U]" into TPK_LEVEL is an
unnecessary and a tad obfuscating change.

This also adds a leading space for unknown reasons
after the KERN_SOH <level>.

> > 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..22fbd483b5dc 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) " [U]"

I think this should be

#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 " %s\n", tpk_buffer);

and this

printk(TPK_PREFIX "[U] %s\n", tpk_buffer);

> > tpk_curr = 0;
> > }
> > }
> > --
> > 2.11.0
> >
>
>

2018-09-07 08:14:31

by Peter Korsgaard

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

>>>>> "Joe" == Joe Perches <[email protected]> writes:

> On Fri, 2018-09-07 at 09:50 +0200, Peter Korsgaard wrote:
>> On Tue, Aug 21, 2018 at 7:28 PM Peter Korsgaard <[email protected]> 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.
>>
>> Ping? Feedback, comments?

> I think it is moving "[U]" into TPK_LEVEL is an
> unnecessary and a tad obfuscating change.

It is arguably part of the prefix, but OK - I have no problem leaving it
in the printk line.

> This also adds a leading space for unknown reasons
> after the KERN_SOH <level>.

True. I'll fix that and send a v2 - Thanks.

>> > 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..22fbd483b5dc 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) " [U]"

> I think this should be

> #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 " %s\n", tpk_buffer);

> and this

> printk(TPK_PREFIX "[U] %s\n", tpk_buffer);

>> > tpk_curr = 0;
>> > }
>> > }
>> > --
>> > 2.11.0
>> >
>>
>>

--
Bye, Peter Korsgaard