| Message ID | 20190913185746.337429-5-andrealmeid@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | null_blk: fixes around nr_devices and log improvements | expand |
On Fri, 2019-09-13 at 15:57 -0300, André Almeida wrote: > The pr_fmt macro is useful to format log messages printed by pr_XXXX() > functions. Add text to explain the purpose of it, how to use and an > example. [] > diff --git a/Documentation/process/coding-style.rst b/Documentation/process/coding-style.rst [] > @@ -819,7 +819,15 @@ which you should use to make sure messages are matched to the right device > and driver, and are tagged with the right level: dev_err(), dev_warn(), > dev_info(), and so forth. For messages that aren't associated with a > particular device, <linux/printk.h> defines pr_notice(), pr_info(), > -pr_warn(), pr_err(), etc. > +pr_warn(), pr_err(), etc. It's possible to format pr_XXX() messages using the > +macro pr_fmt() to prevent rewriting the style of messages. It should be > +defined before including ``include/printk.h``, to avoid compiler warning about Please make this '#include <linux/kernel.h>' printk.h should normally not be #included.
On 9/13/19 4:08 PM, Joe Perches wrote: > On Fri, 2019-09-13 at 15:57 -0300, André Almeida wrote: >> The pr_fmt macro is useful to format log messages printed by pr_XXXX() >> functions. Add text to explain the purpose of it, how to use and an >> example. > [] >> diff --git a/Documentation/process/coding-style.rst b/Documentation/process/coding-style.rst > [] >> @@ -819,7 +819,15 @@ which you should use to make sure messages are matched to the right device >> and driver, and are tagged with the right level: dev_err(), dev_warn(), >> dev_info(), and so forth. For messages that aren't associated with a >> particular device, <linux/printk.h> defines pr_notice(), pr_info(), >> -pr_warn(), pr_err(), etc. >> +pr_warn(), pr_err(), etc. It's possible to format pr_XXX() messages using the >> +macro pr_fmt() to prevent rewriting the style of messages. It should be >> +defined before including ``include/printk.h``, to avoid compiler warning about > > Please make this '#include <linux/kernel.h>' > > printk.h should normally not be #included. > Thanks for the feedback, changed for v2.
On 9/13/19 11:57 AM, André Almeida wrote: > The pr_fmt macro is useful to format log messages printed by pr_XXXX() > functions. Add text to explain the purpose of it, how to use and an > example. > > Signed-off-by: André Almeida <andrealmeid@collabora.com> Since Jonathan Corbet is documentation maintainer, shouldn't he be Cc'ed explicitly for documentation patches? See also the MAINTAINERS file. Bart.
On Fri, 13 Sep 2019 13:22:18 -0700 Bart Van Assche <bvanassche@acm.org> wrote: > On 9/13/19 11:57 AM, André Almeida wrote: > > The pr_fmt macro is useful to format log messages printed by pr_XXXX() > > functions. Add text to explain the purpose of it, how to use and an > > example. > > > > Signed-off-by: André Almeida <andrealmeid@collabora.com> > > Since Jonathan Corbet is documentation maintainer, shouldn't he be Cc'ed > explicitly for documentation patches? See also the MAINTAINERS file. ...and indeed I was CC'd on the patch - and your response :) Thanks, jon
diff --git a/Documentation/process/coding-style.rst b/Documentation/process/coding-style.rst index f4a2198187f9..276787bc2ff2 100644 --- a/Documentation/process/coding-style.rst +++ b/Documentation/process/coding-style.rst @@ -819,7 +819,15 @@ which you should use to make sure messages are matched to the right device and driver, and are tagged with the right level: dev_err(), dev_warn(), dev_info(), and so forth. For messages that aren't associated with a particular device, <linux/printk.h> defines pr_notice(), pr_info(), -pr_warn(), pr_err(), etc. +pr_warn(), pr_err(), etc. It's possible to format pr_XXX() messages using the +macro pr_fmt() to prevent rewriting the style of messages. It should be +defined before including ``include/printk.h``, to avoid compiler warning about +redefinitions. This is particularly useful for adding the name of the module at +the beginning of the message, for instance: + +.. code-block:: c + + #define pr_fmt(fmt) "module_name: " fmt Coming up with good debugging messages can be quite a challenge; and once you have them, they can be a huge help for remote troubleshooting. However
The pr_fmt macro is useful to format log messages printed by pr_XXXX() functions. Add text to explain the purpose of it, how to use and an example. Signed-off-by: André Almeida <andrealmeid@collabora.com> --- Documentation/process/coding-style.rst | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)