[PATCH] tracing: Fix undelared ENOSYS in include/linux/tracepoint.h

[PATCH] tracing: Fix undelared ENOSYS in include/linux/tracepoint.h

[Wu Zhangjin]

From: Wu Zhangjin <wuzhangjin@gmail.com>

The header file include/linux/tracepoint.h may be included without
include/linux/errno.h and then the compiler will fail on building for
undelcared ENOSYS. This patch fixes this problem via including <linux/errno.h>
to include/linux/tracepoint.h.

Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
---
 include/linux/tracepoint.h |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index 9a59d1f..103d1b6 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -14,6 +14,7 @@
  * See the file COPYING for more details.
  */
 
+#include <linux/errno.h>
 #include <linux/types.h>
 #include <linux/rcupdate.h>
 
-- 
1.6.3.3

Re: [PATCH] tracing: Fix undelared ENOSYS in include/linux/tracepoint.h

[Steven Rostedt]

On Mon, 2010-06-21 at 19:09 +0800, Wu Zhangjin wrote:
> From: Wu Zhangjin <wuzhangjin@gmail.com>
> 
> The header file include/linux/tracepoint.h may be included without
> include/linux/errno.h and then the compiler will fail on building for
> undelcared ENOSYS. This patch fixes this problem via including <linux/errno.h>
> to include/linux/tracepoint.h.
> 

Hi Wu,

I have not hit this. Did you hit this with mips? Does it need to get
into 2.6.35 or can it wait till 2.6.36?

-- Steve

> Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
> ---
>  include/linux/tracepoint.h |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
> index 9a59d1f..103d1b6 100644
> --- a/include/linux/tracepoint.h
> +++ b/include/linux/tracepoint.h
> @@ -14,6 +14,7 @@
>   * See the file COPYING for more details.
>   */
>  
> +#include <linux/errno.h>
>  #include <linux/types.h>
>  #include <linux/rcupdate.h>
>  

Re: [PATCH] tracing: Fix undelared ENOSYS in include/linux/tracepoint.h

[Mathieu Desnoyers]

* Steven Rostedt (rostedt@goodmis.org) wrote:
> On Mon, 2010-06-21 at 19:09 +0800, Wu Zhangjin wrote:
> > From: Wu Zhangjin <wuzhangjin@gmail.com>
> > 
> > The header file include/linux/tracepoint.h may be included without
> > include/linux/errno.h and then the compiler will fail on building for
> > undelcared ENOSYS. This patch fixes this problem via including <linux/errno.h>
> > to include/linux/tracepoint.h.
> > 
> 
> Hi Wu,
> 
> I have not hit this. Did you hit this with mips? Does it need to get
> into 2.6.35 or can it wait till 2.6.36?

errno.h is included by sched.h, which is included almost everywhere. No
wonder it took that much time for someone to hit the problem. But given
it's a simple bug fix, it should fit into the "for-2.6.35" definition,
although I am no expert in these definitions. ;-)

Thanks,

Mathieu

> 
> -- Steve
> 
> > Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
> > ---
> >  include/linux/tracepoint.h |    1 +
> >  1 files changed, 1 insertions(+), 0 deletions(-)
> > 
> > diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
> > index 9a59d1f..103d1b6 100644
> > --- a/include/linux/tracepoint.h
> > +++ b/include/linux/tracepoint.h
> > @@ -14,6 +14,7 @@
> >   * See the file COPYING for more details.
> >   */
> >  
> > +#include <linux/errno.h>
> >  #include <linux/types.h>
> >  #include <linux/rcupdate.h>
> >  
> 
> 

-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com

Re: [PATCH] tracing: Fix undelared ENOSYS in include/linux/tracepoint.h

[Steven Rostedt]

On Mon, 2010-06-21 at 11:47 -0400, Mathieu Desnoyers wrote:
> * Steven Rostedt (rostedt@goodmis.org) wrote:
> > On Mon, 2010-06-21 at 19:09 +0800, Wu Zhangjin wrote:
> > > From: Wu Zhangjin <wuzhangjin@gmail.com>
> > > 
> > > The header file include/linux/tracepoint.h may be included without
> > > include/linux/errno.h and then the compiler will fail on building for
> > > undelcared ENOSYS. This patch fixes this problem via including <linux/errno.h>
> > > to include/linux/tracepoint.h.
> > > 
> > 
> > Hi Wu,
> > 
> > I have not hit this. Did you hit this with mips? Does it need to get
> > into 2.6.35 or can it wait till 2.6.36?
> 
> errno.h is included by sched.h, which is included almost everywhere. No
> wonder it took that much time for someone to hit the problem. But given
> it's a simple bug fix, it should fit into the "for-2.6.35" definition,
> although I am no expert in these definitions. ;-)

Usually I would agree. But lately Linus has been very strict in what
goes into 35.

Thus, I would say, it should go into 35 if it breaks a configuration
build of things already in 35. Otherwise, it can wait till 36.

Of course this is an extremely trivial fix, and maybe there's a
configuration already in 35 that we don't know about that this bug can
break. I guess I'll just pull it in for a 35 push.

-- Steve

Re: [PATCH] tracing: Fix undelared ENOSYS in include/linux/tracepoint.h

[Wu Zhangjin]

On Mon, 2010-06-21 at 10:28 -0400, Steven Rostedt wrote:
> On Mon, 2010-06-21 at 19:09 +0800, Wu Zhangjin wrote:
> > From: Wu Zhangjin <wuzhangjin@gmail.com>
> > 
> > The header file include/linux/tracepoint.h may be included without
> > include/linux/errno.h and then the compiler will fail on building for
> > undelcared ENOSYS. This patch fixes this problem via including <linux/errno.h>
> > to include/linux/tracepoint.h.
> > 
> 
> Hi Wu,
> 
> I have not hit this. Did you hit this with mips? Does it need to get
> into 2.6.35 or can it wait till 2.6.36?
> 

I did not hit this in the mainline linux but in the windriver linux
(2.6.34). some guys (from WR) have included the <linux/kmemtrace.h> in
lib/kernel_lock.c and have introduced the building failure under some
configurations(seems when disabling the LTTng and another config, sorry,
I forget the exact name).

I have tried to find out who have used the undeclared ENOSYS and at last
got include/linux/tracepoint.h and after checking the linux-next tree
and found it also need to declare ENOSYS, then I send this patch for I'm
worrying about somebody else may also include tracepoint.h but without
errno.h ;)

Perhaps we'd better push it into 2.6.35 as you explained: "maybe there's
a configuration already in 35 that we don't know about that this bug can
break. "

Best Regards,
	Wu Zhangjin

> -- Steve
> 
> > Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
> > ---
> >  include/linux/tracepoint.h |    1 +
> >  1 files changed, 1 insertions(+), 0 deletions(-)
> > 
> > diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
> > index 9a59d1f..103d1b6 100644
> > --- a/include/linux/tracepoint.h
> > +++ b/include/linux/tracepoint.h
> > @@ -14,6 +14,7 @@
> >   * See the file COPYING for more details.
> >   */
> >  
> > +#include <linux/errno.h>
> >  #include <linux/types.h>
> >  #include <linux/rcupdate.h>
> >  
> 
> 

[tip:perf/urgent] tracing: Fix undeclared ENOSYS in include/linux/tracepoint.h

[tip-bot for Wu Zhangjin]

Commit-ID:  b70e4f0529c089b00d0a6da13106db4de1ada4c7
Gitweb:     http://git.kernel.org/tip/b70e4f0529c089b00d0a6da13106db4de1ada4c7
Author:     Wu Zhangjin <wuzhangjin@gmail.com>
AuthorDate: Mon, 21 Jun 2010 19:09:09 +0800
Committer:  Steven Rostedt <rostedt@goodmis.org>
CommitDate: Mon, 21 Jun 2010 12:23:36 -0400

tracing: Fix undeclared ENOSYS in include/linux/tracepoint.h

The header file include/linux/tracepoint.h may be included without
include/linux/errno.h and then the compiler will fail on building for
undelcared ENOSYS. This patch fixes this problem via including <linux/errno.h>
to include/linux/tracepoint.h.

Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
LKML-Reference: <1277118549-622-1-git-send-email-wuzhangjin@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 include/linux/tracepoint.h |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index 9a59d1f..103d1b6 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -14,6 +14,7 @@
  * See the file COPYING for more details.
  */
 
+#include <linux/errno.h>
 #include <linux/types.h>
 #include <linux/rcupdate.h>