linux-next: ftrace tree build warnings

linux-next: ftrace tree build warnings

[Stephen Rothwell]

[-- Attachment #1: Type: text/plain, Size: 549 bytes --]

Hi all,

Today's linux-next build (x86_64 allmodconfig) produced lots of these
warnings:

include/linux/tty.h:330: warning: '______f' is static but declared in inline function 'tty_kref_get' which is not static

Caused by commit 2bcd521a684cc94befbe2ce7d5b613c841b0d304 ("trace:
profile all if conditionals").  Something needs to be done about
this ...  maybe tty_kref_get needs to be "static inline" instead of
"extern inline"?

-- 
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au
http://www.canb.auug.org.au/~sfr/

[-- Attachment #2: Type: application/pgp-signature, Size: 197 bytes --]

Re: linux-next: ftrace tree build warnings

[Steven Rostedt]

On Tue, 2008-11-25 at 13:38 +1100, Stephen Rothwell wrote:
> Hi all,
> 
> Today's linux-next build (x86_64 allmodconfig) produced lots of these
> warnings:
> 
> include/linux/tty.h:330: warning: '______f' is static but declared in inline function 'tty_kref_get' which is not static
> 
> Caused by commit 2bcd521a684cc94befbe2ce7d5b613c841b0d304 ("trace:
> profile all if conditionals").  Something needs to be done about
> this ...  maybe tty_kref_get needs to be "static inline" instead of
> "extern inline"?
> 

Is there a way to suppress this warning here? Since we are only
profiling, if it complies fine, then it should not be an issue.


Looking at the uses of this function, is there any reason that it is not
"static inline"?

-- Steve
 

Re: linux-next: ftrace tree build warnings

[Ingo Molnar]

* Stephen Rothwell <sfr@canb.auug.org.au> wrote:

> Hi all,
> 
> Today's linux-next build (x86_64 allmodconfig) produced lots of these
> warnings:
> 
> include/linux/tty.h:330: warning: '______f' is static but declared in inline function 'tty_kref_get' which is not static
> 
> Caused by commit 2bcd521a684cc94befbe2ce7d5b613c841b0d304 ("trace:
> profile all if conditionals").  Something needs to be done about
> this ...  maybe tty_kref_get needs to be "static inline" instead of
> "extern inline"?

i've queued up the fix below, and pushed out a new ftrace-next tree.

Thanks,

	Ingo

------------------>
From 14bfc987e395797dfe03e915e8b4c7fc9e5078e4 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Tue, 25 Nov 2008 08:58:11 +0100
Subject: [PATCH] tracing, tty: fix warnings caused by branch tracing and tty_kref_get()
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit

Stephen Rothwell reported tht this warning started triggering in
linux-next:

  In file included from init/main.c:27:
  include/linux/tty.h: In function ‘tty_kref_get’:
  include/linux/tty.h:330: warning: ‘______f’ is static but declared in inline function ‘tty_kref_get’ which is not static

Which gcc emits for 'extern inline' functions that nevertheless define
static variables. Change it to 'static inline', which is the norm
in the kernel anyway.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 include/linux/tty.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/include/linux/tty.h b/include/linux/tty.h
index 3b8121d..eaec37c 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -325,7 +325,7 @@ extern struct class *tty_class;
  *	go away
  */
 
-extern inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
+static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
 {
 	if (tty)
 		kref_get(&tty->kref);

Re: linux-next: ftrace tree build warnings

[Stephen Rothwell]

[-- Attachment #1: Type: text/plain, Size: 278 bytes --]

Hi Ingo,

On Tue, 25 Nov 2008 09:00:35 +0100 Ingo Molnar <mingo@elte.hu> wrote:
>
> i've queued up the fix below, and pushed out a new ftrace-next tree.

Thanks.

-- 
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au
http://www.canb.auug.org.au/~sfr/

[-- Attachment #2: Type: application/pgp-signature, Size: 197 bytes --]

Re: linux-next: ftrace tree build warnings

[Alan Cox]

On Tue, 25 Nov 2008 13:38:28 +1100
Stephen Rothwell <sfr@canb.auug.org.au> wrote:

> Hi all,
> 
> Today's linux-next build (x86_64 allmodconfig) produced lots of these
> warnings:
> 
> include/linux/tty.h:330: warning: '______f' is static but declared in inline function 'tty_kref_get' which is not static
> 
> Caused by commit 2bcd521a684cc94befbe2ce7d5b613c841b0d304 ("trace:
> profile all if conditionals").  Something needs to be done about
> this ...  maybe tty_kref_get needs to be "static inline" instead of
> "extern inline"?

If someone from the ftrace crew can sort the problem out and send me a
diff for the ttydev tree that shouldn't be a problem, but really it looks
like a problem with ftrace as that can't be the only case this happens
surely ?

[PATCH] tracing, tty: fix warnings caused by branch tracing and tty_kref_get()

[Ingo Molnar]

* Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:

> On Tue, 25 Nov 2008 13:38:28 +1100
> Stephen Rothwell <sfr@canb.auug.org.au> wrote:
> 
> > Hi all,
> > 
> > Today's linux-next build (x86_64 allmodconfig) produced lots of these
> > warnings:
> > 
> > include/linux/tty.h:330: warning: '______f' is static but declared in inline function 'tty_kref_get' which is not static
> > 
> > Caused by commit 2bcd521a684cc94befbe2ce7d5b613c841b0d304 ("trace:
> > profile all if conditionals").  Something needs to be done about
> > this ...  maybe tty_kref_get needs to be "static inline" instead of
> > "extern inline"?
> 
> If someone from the ftrace crew can sort the problem out and send me 
> a diff for the ttydev tree that shouldn't be a problem, but really 
> it looks like a problem with ftrace as that can't be the only case 
> this happens surely ?

i've done quite wide build testing of it and tty.h seems to be the 
only affected file triggering a warning due to this. ('extern inline' 
has been eliminated from most of the kernel in recent cycles)

	Ingo

---------------->
From 14bfc987e395797dfe03e915e8b4c7fc9e5078e4 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Tue, 25 Nov 2008 08:58:11 +0100
Subject: [PATCH] tracing, tty: fix warnings caused by branch tracing and tty_kref_get()
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit

Stephen Rothwell reported tht this warning started triggering in
linux-next:

  In file included from init/main.c:27:
  include/linux/tty.h: In function ‘tty_kref_get’:
  include/linux/tty.h:330: warning: ‘______f’ is static but declared in inline function ‘tty_kref_get’ which is not static

Which gcc emits for 'extern inline' functions that nevertheless define
static variables. Change it to 'static inline', which is the norm
in the kernel anyway.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 include/linux/tty.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/include/linux/tty.h b/include/linux/tty.h
index 3b8121d..eaec37c 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -325,7 +325,7 @@ extern struct class *tty_class;
  *	go away
  */
 
-extern inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
+static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
 {
 	if (tty)
 		kref_get(&tty->kref);