%pC and %pCn print the same string, and commit 900cca294425 ("lib/vsprintf:
add %pC{,n,r} format specifiers for clocks") introducing them does not
clarify any intended difference. It can be assumed %pC is a default for
%pCn as some other specifiers do, but not all are consistent with this
policy. Moreover there is now no other suffix other than 'n', which makes a
default not really useful.
All users in the kernel were using %pC except for one which has been
converted. So now remove %pCn and all the unnecessary extra code and
documentation.
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
---
Documentation/core-api/printk-formats.rst | 3 +--
lib/vsprintf.c | 10 ++--------
2 files changed, 3 insertions(+), 10 deletions(-)
diff --git a/Documentation/core-api/printk-formats.rst b/Documentation/core-api/printk-formats.rst
index ecccc0473da9c10f45f2464566f690472c61401e..f3009e6ec80a864c330c8812efcd82c12f4066b3 100644
--- a/Documentation/core-api/printk-formats.rst
+++ b/Documentation/core-api/printk-formats.rst
@@ -571,9 +571,8 @@ struct clk
::
%pC pll1
- %pCn pll1
-For printing struct clk structures. %pC and %pCn print the name of the clock
+For printing struct clk structures. %pC prints the name of the clock
(Common Clock Framework) or a unique 32-bit ID (legacy clock framework).
Passed by reference.
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 56fe96319292674c9f79559cf78dd0d99d1a1f06..143d55cb1c12acac21a6c6bafd255437e878f280 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1969,15 +1969,11 @@ char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
if (check_pointer(&buf, end, clk, spec))
return buf;
- switch (fmt[1]) {
- case 'n':
- default:
#ifdef CONFIG_COMMON_CLK
- return string(buf, end, __clk_get_name(clk), spec);
+ return string(buf, end, __clk_get_name(clk), spec);
#else
- return ptr_to_id(buf, end, clk, spec);
+ return ptr_to_id(buf, end, clk, spec);
#endif
- }
}
static
@@ -2382,8 +2378,6 @@ char *rust_fmt_argument(char *buf, char *end, void *ptr);
* T time64_t
* - 'C' For a clock, it prints the name (Common Clock Framework) or address
* (legacy clock framework) of the clock
- * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
- * (legacy clock framework) of the clock
* - 'G' For flags to be printed as a collection of symbolic strings that would
* construct the specific value. Supported flags given by option:
* p page flags (see struct page) given as pointer to unsigned long
--
2.48.1Quoting Luca Ceresoli (2025-03-07 03:19:08)
> %pC and %pCn print the same string, and commit 900cca294425 ("lib/vsprintf:
> add %pC{,n,r} format specifiers for clocks") introducing them does not
> clarify any intended difference. It can be assumed %pC is a default for
> %pCn as some other specifiers do, but not all are consistent with this
> policy. Moreover there is now no other suffix other than 'n', which makes a
> default not really useful.
>
> All users in the kernel were using %pC except for one which has been
> converted. So now remove %pCn and all the unnecessary extra code and
> documentation.
>
> Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
> ---
Acked-by: Stephen Boyd <sboyd@kernel.org>
On Fri, Mar 07, 2025 at 12:19:08PM +0100, Luca Ceresoli wrote:
> %pC and %pCn print the same string, and commit 900cca294425 ("lib/vsprintf:
> add %pC{,n,r} format specifiers for clocks") introducing them does not
> clarify any intended difference. It can be assumed %pC is a default for
> %pCn as some other specifiers do, but not all are consistent with this
> policy. Moreover there is now no other suffix other than 'n', which makes a
> default not really useful.
>
> All users in the kernel were using %pC except for one which has been
> converted. So now remove %pCn and all the unnecessary extra code and
> documentation.
You seem forgot to update translation(s) of the documentation.
--
With Best Regards,
Andy Shevchenko
Hello Andy,
On Fri, 7 Mar 2025 19:17:26 +0200
Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> On Fri, Mar 07, 2025 at 12:19:08PM +0100, Luca Ceresoli wrote:
> > %pC and %pCn print the same string, and commit 900cca294425 ("lib/vsprintf:
> > add %pC{,n,r} format specifiers for clocks") introducing them does not
> > clarify any intended difference. It can be assumed %pC is a default for
> > %pCn as some other specifiers do, but not all are consistent with this
> > policy. Moreover there is now no other suffix other than 'n', which makes a
> > default not really useful.
> >
> > All users in the kernel were using %pC except for one which has been
> > converted. So now remove %pCn and all the unnecessary extra code and
> > documentation.
>
> You seem forgot to update translation(s) of the documentation.
I'm afraid I don't speak Chinese. :-)
For this specific change I think I could come up with an approximation
of it, but the both the docs and git log suggest this is not expected.
Luca
--
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
On Sat, Mar 08, 2025 at 12:34:25AM +0100, Luca Ceresoli wrote:
> On Fri, 7 Mar 2025 19:17:26 +0200
> Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> > On Fri, Mar 07, 2025 at 12:19:08PM +0100, Luca Ceresoli wrote:
> > > %pC and %pCn print the same string, and commit 900cca294425 ("lib/vsprintf:
> > > add %pC{,n,r} format specifiers for clocks") introducing them does not
> > > clarify any intended difference. It can be assumed %pC is a default for
> > > %pCn as some other specifiers do, but not all are consistent with this
> > > policy. Moreover there is now no other suffix other than 'n', which makes a
> > > default not really useful.
> > >
> > > All users in the kernel were using %pC except for one which has been
> > > converted. So now remove %pCn and all the unnecessary extra code and
> > > documentation.
> >
> > You seem forgot to update translation(s) of the documentation.
>
> I'm afraid I don't speak Chinese. :-)
At bare minimum we can drop the same line in the list.
Also in such a case we may ask a Chinese speaking person to review / correct /
suggest the changes. I would not leave a leftover as it will be forgotten so
easily and documentation becomes not in sync.
> For this specific change I think I could come up with an approximation
> of it, but the both the docs and git log suggest this is not expected.
--
With Best Regards,
Andy Shevchenko
Hello,
+To: Alex Shi, Yanteng Si (Chinese docs maintainers)
+Cc: Binbin Zhou (contributor to English version of printk-formats.rst)
On Mon, 10 Mar 2025 10:17:14 +0200
Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> On Sat, Mar 08, 2025 at 12:34:25AM +0100, Luca Ceresoli wrote:
> > On Fri, 7 Mar 2025 19:17:26 +0200
> > Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> > > On Fri, Mar 07, 2025 at 12:19:08PM +0100, Luca Ceresoli wrote:
> > > > %pC and %pCn print the same string, and commit 900cca294425 ("lib/vsprintf:
> > > > add %pC{,n,r} format specifiers for clocks") introducing them does not
> > > > clarify any intended difference. It can be assumed %pC is a default for
> > > > %pCn as some other specifiers do, but not all are consistent with this
> > > > policy. Moreover there is now no other suffix other than 'n', which makes a
> > > > default not really useful.
> > > >
> > > > All users in the kernel were using %pC except for one which has been
> > > > converted. So now remove %pCn and all the unnecessary extra code and
> > > > documentation.
> > >
> > > You seem forgot to update translation(s) of the documentation.
> >
> > I'm afraid I don't speak Chinese. :-)
>
> At bare minimum we can drop the same line in the list.
> Also in such a case we may ask a Chinese speaking person to review / correct /
> suggest the changes. I would not leave a leftover as it will be forgotten so
> easily and documentation becomes not in sync.
Alex Shi, Yanteng Si: what is the process to update the Chinese
documentation after changes to the English one, considering I don't
speak Chinese?
The documentation [0] seems to imply it will be done by you after the
English documentation update, is it the case?
Otherwise, for this simple change, I can add a patch that looks like a
somewhat correct one for Chinese:
@@ -523,9 +523,8 @@ clk结构体
::
%pC pll1
- %pCn pll1
-用于打印clk结构。%pC 和 %pCn 打印时钟的名称（通用时钟框架）或唯一的32位
+用于打印clk结构。%pC 打印时钟的名称（通用时钟框架）或唯一的32位
ID（传统时钟框架）。
通过引用传递。
Can you confirm the above is a correct change?
Luca
[0] https://docs.kernel.org/translations/index.html
--
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
Hi Luca,
On Fri, 7 Mar 2025 at 12:19, Luca Ceresoli <luca.ceresoli@bootlin.com> wrote:
> %pC and %pCn print the same string, and commit 900cca294425 ("lib/vsprintf:
> add %pC{,n,r} format specifiers for clocks") introducing them does not
> clarify any intended difference. It can be assumed %pC is a default for
> %pCn as some other specifiers do, but not all are consistent with this
> policy. Moreover there is now no other suffix other than 'n', which makes a
> default not really useful.
The original intention was indeed to serve as a default, like some
other formats also have ("%pa[p]", %pOF[f]").
> All users in the kernel were using %pC except for one which has been
> converted. So now remove %pCn and all the unnecessary extra code and
> documentation.
>
> Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
I guess this is a worthwhile cleanup.
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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