Next April 24: [S390] allmodconfig build failure (trace/events)

Next April 24: [S390] allmodconfig build failure (trace/events)

[Sachin Sant]

Today's next tree build(s390 allmodconfig) failed with

kernel/built-in.o: In function `trace_softirq_entry'
include/trace/events/irq.h:42: undefined reference to 
`__tracepoint_softirq_entry'
include/trace/events/irq.h:42: undefined reference to 
`__tracepoint_softirq_entry'
kernel/built-in.o: In function `trace_softirq_exit':
include/trace/events/irq.h:48: undefined reference to 
`__tracepoint_softirq_exit'
include/trace/events/irq.h:48: undefined reference to 
`__tracepoint_softirq_exit'

Thanks
-Sachin

-- 

---------------------------------
Sachin Sant
IBM Linux Technology Center
India Systems and Technology Labs
Bangalore, India
---------------------------------

Re: Next April 24: [S390] allmodconfig build failure (trace/events)

[Ingo Molnar]

* Sachin Sant <sachinp@in.ibm.com> wrote:

> Today's next tree build(s390 allmodconfig) failed with
>
> kernel/built-in.o: In function `trace_softirq_entry'
> include/trace/events/irq.h:42: undefined reference to  
> `__tracepoint_softirq_entry'
> include/trace/events/irq.h:42: undefined reference to  
> `__tracepoint_softirq_entry'
> kernel/built-in.o: In function `trace_softirq_exit':
> include/trace/events/irq.h:48: undefined reference to  
> `__tracepoint_softirq_exit'
> include/trace/events/irq.h:48: undefined reference to  
> `__tracepoint_softirq_exit'

Hm, that's weird - s390 does not build kernel/softirq.o? Hm, it does 
- softirq.o is an obj-y object.

	Ingo

Re: Next April 24: [S390] allmodconfig build failure (trace/events)

[Heiko Carstens]

On Fri, 24 Apr 2009 09:25:33 +0200
Ingo Molnar <mingo@elte.hu> wrote:

> 
> * Sachin Sant <sachinp@in.ibm.com> wrote:
> 
> > Today's next tree build(s390 allmodconfig) failed with
> >
> > kernel/built-in.o: In function `trace_softirq_entry'
> > include/trace/events/irq.h:42: undefined reference to  
> > `'
> > include/trace/events/irq.h:42: undefined reference to  
> > `__tracepoint_softirq_entry'
> > kernel/built-in.o: In function `trace_softirq_exit':
> > include/trace/events/irq.h:48: undefined reference to  
> > `__tracepoint_softirq_exit'
> > include/trace/events/irq.h:48: undefined reference to  
> > `__tracepoint_softirq_exit'
> 
> Hm, that's weird - s390 does not build kernel/softirq.o? Hm, it does 
> - softirq.o is an obj-y object.

s390 does build kernel/softirq.o. However it's anything but obvious to
me how the tracepoint infrastructure works. Too many #ifdefs, #define's
and #undefine's...

I would expect that struct __tracepoint_softirq_entry somehow gets
defined via one of the TRACE_FORMAT macros, no?

kernel/softirq.i has these parts wrt. __tracepoint_softirq_entry:

# 42 "include/trace/events/irq.h"
extern struct tracepoint __tracepoint_softirq_entry; static inline __attribute__((always_inline)) void trace_softirq_entry(struc
t softirq_action *h, struct softirq_action *vec) { if (__builtin_expect(!!(__tracepoint_softirq_entry.state), 0)) do { void **it
_func; do { } while (0); it_func = ({ typeof((&__tracepoint_softirq_entry)->funcs) _________p1 = (*(volatile typeof((&__tracepoi
nt_softirq_entry)->funcs) *)&((&__tracepoint_softirq_entry)->funcs)); do { } while(0); (_________p1); }); if (it_func) { do { ((
void(*)(struct softirq_action *h, struct softirq_action *vec))(*it_func))(h, vec); } while (*(++it_func)); } do { } while (0); }
 while (0); } static inline __attribute__((always_inline)) int register_trace_softirq_entry(void (*probe)(struct softirq_action 
*h, struct softirq_action *vec)) { return tracepoint_probe_register("softirq_entry", (void *)probe); } static inline __attribute
__((always_inline)) int unregister_trace_softirq_entry(void (*probe)(struct softirq_action *h, struct softirq_action *vec)) { re
turn tracepoint_probe_unregister("softirq_entry", (void *)probe); };

extern struct tracepoint __tracepoint_softirq_exit; static inline __attribute__((always_inline)) void trace_softirq_exit(struct 
softirq_action *h, struct softirq_action *vec) { if (__builtin_expect(!!(__tracepoint_softirq_exit.state), 0)) do { void **it_fu
nc; do { } while (0); it_func = ({ typeof((&__tracepoint_softirq_exit)->funcs) _________p1 = (*(volatile typeof((&__tracepoint_s
oftirq_exit)->funcs) *)&((&__tracepoint_softirq_exit)->funcs)); do { } while(0); (_________p1); }); if (it_func) { do { ((void(*
)(struct softirq_action *h, struct softirq_action *vec))(*it_func))(h, vec); } while (*(++it_func)); } do { } while (0); } while
 (0); } static inline __attribute__((always_inline)) int register_trace_softirq_exit(void (*probe)(struct softirq_action *h, str
uct softirq_action *vec)) { return tracepoint_probe_register("softirq_exit", (void *)probe); } static inline __attribute__((alwa
ys_inline)) int unregister_trace_softirq_exit(void (*probe)(struct softirq_action *h, struct softirq_action *vec)) { return trac
epoint_probe_unregister("softirq_exit", (void *)probe); };

__do_softirq looks like below. So I would expect some header file include dependency? Dunno...

 void __do_softirq(void)
{
 struct softirq_action *h;
 __u32 pending;
 int max_restart = 10;
 int cpu;

 pending = ((*((struct _lowcore *) 0)).softirq_pending);
 account_system_vtime(((struct task_struct *const)(*((struct _lowcore *) 0)).current_task));

 __local_bh_disable((unsigned long)__builtin_return_address(0));
 do { ((struct task_struct *const)(*((struct _lowcore *) 0)).current_task)->softirq_context++; } while (0);

 cpu = ((*((struct _lowcore *) 0)).cpu_nr);
restart:

 (((*((struct _lowcore *) 0)).softirq_pending) = (0));

 do { trace_hardirqs_on(); raw_local_irq_enable(); } while (0);

 h = softirq_vec;

 do {
  if (pending & 1) {
   int prev_count = (current_thread_info()->preempt_count);

   trace_softirq_entry(h, softirq_vec);
   h->action(h);
   trace_softirq_exit(h, softirq_vec);
   if (__builtin_expect(!!(prev_count != (current_thread_info()->preempt_count)), 0)) {
    printk("<3>" "huh, entered softirq %td %s %p"
           "with preempt_count %08x,"
           " exited with %08x?\n", h - softirq_vec,
           softirq_to_name[h - softirq_vec],
           h->action, prev_count, (current_thread_info()->preempt_count));
    (current_thread_info()->preempt_count) = prev_count;
   }

   rcu_bh_qsctr_inc(cpu);
  }
  h++;
  pending >>= 1;
 } while (pending);

 do { raw_local_irq_disable(); trace_hardirqs_off(); } while (0);

 pending = ((*((struct _lowcore *) 0)).softirq_pending);
 if (pending && --max_restart)
  goto restart;

 if (pending)
  wakeup_softirqd();

 do { ((struct task_struct *const)(*((struct _lowcore *) 0)).current_task)->softirq_context--; } while (0);

 account_system_vtime(((struct task_struct *const)(*((struct _lowcore *) 0)).current_task));
 _local_bh_enable();
}

Re: Next April 24: [S390] allmodconfig build failure (trace/events)

[Sachin Sant]

Heiko Carstens wrote:
> On Fri, 24 Apr 2009 09:25:33 +0200
> Ingo Molnar <mingo@elte.hu> wrote:
>
>   
>> * Sachin Sant <sachinp@in.ibm.com> wrote:
>>
>>     
>>> Today's next tree build(s390 allmodconfig) failed with
>>>
>>> kernel/built-in.o: In function `trace_softirq_entry'
>>> include/trace/events/irq.h:42: undefined reference to  
>>> `'
>>> include/trace/events/irq.h:42: undefined reference to  
>>> `__tracepoint_softirq_entry'
>>> kernel/built-in.o: In function `trace_softirq_exit':
>>> include/trace/events/irq.h:48: undefined reference to  
>>> `__tracepoint_softirq_exit'
>>> include/trace/events/irq.h:48: undefined reference to  
>>> `__tracepoint_softirq_exit'
>>>       
>> Hm, that's weird - s390 does not build kernel/softirq.o? Hm, it does 
>> - softirq.o is an obj-y object.
>>     
>
> s390 does build kernel/softirq.o. However it's anything but obvious to
> me how the tracepoint infrastructure works. Too many #ifdefs, #define's
> and #undefine's...
>
> I would expect that struct __tracepoint_softirq_entry somehow gets
> defined via one of the TRACE_FORMAT macros, no?
Today's next tree also has this failure. Any solution for this problem ?

Thanks
-Sachin

-- 

---------------------------------
Sachin Sant
IBM Linux Technology Center
India Systems and Technology Labs
Bangalore, India
---------------------------------

Re: Next April 24: [S390] allmodconfig build failure (trace/events)

[Heiko Carstens]

On Wed, 29 Apr 2009 15:21:39 +0530
Sachin Sant <sachinp@in.ibm.com> wrote:
> Heiko Carstens wrote:
> > On Fri, 24 Apr 2009 09:25:33 +0200
> > Ingo Molnar <mingo@elte.hu> wrote:
> >> * Sachin Sant <sachinp@in.ibm.com> wrote:
> >>> Today's next tree build(s390 allmodconfig) failed with
> >>>
> >>> kernel/built-in.o: In function `trace_softirq_entry'
> >>> include/trace/events/irq.h:42: undefined reference to  
> >>> `'
> >>> include/trace/events/irq.h:42: undefined reference to  
> >>> `__tracepoint_softirq_entry'
> >>> kernel/built-in.o: In function `trace_softirq_exit':
> >>> include/trace/events/irq.h:48: undefined reference to  
> >>> `__tracepoint_softirq_exit'
> >>> include/trace/events/irq.h:48: undefined reference to  
> >>> `__tracepoint_softirq_exit'
> >>>       
> >> Hm, that's weird - s390 does not build kernel/softirq.o? Hm, it does 
> >> - softirq.o is an obj-y object.
> >
> > s390 does build kernel/softirq.o. However it's anything but obvious to
> > me how the tracepoint infrastructure works. Too many #ifdefs, #define's
> > and #undefine's...
> >
> > I would expect that struct __tracepoint_softirq_entry somehow gets
> > defined via one of the TRACE_FORMAT macros, no?
> Today's next tree also has this failure. Any solution for this problem ?

Ingo, could you pick up the patch below please?

Subject: [PATCH] tracing: fix compile error

From: Heiko Carstens <heiko.carstens@de.ibm.com>

"tracing: create automated trace defines" causes this compile error on s390:

kernel/built-in.o: In function `__do_softirq':
(.text+0x1c680): undefined reference to `__tracepoint_softirq_entry'

This happens because the definitions of the softirq tracepoints were moved
from kernel/softirq.c to kernel/irq/handle.c. Since s390 doesn't support
generic hardirqs handle.c doesn't get compiled and the definitions are
missing.
So move the tracepoints to softirq.c again.

Reported-by: Sachin Sant <sachinp@in.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
---
 kernel/irq/handle.c |    2 --
 kernel/softirq.c    |    2 ++
 2 files changed, 2 insertions(+), 2 deletions(-)

Index: linux-next/kernel/irq/handle.c
===================================================================
--- linux-next.orig/kernel/irq/handle.c
+++ linux-next/kernel/irq/handle.c
@@ -18,8 +18,6 @@
 #include <linux/rculist.h>
 #include <linux/hash.h>
 #include <linux/bootmem.h>
-
-#define CREATE_TRACE_POINTS
 #include <trace/events/irq.h>
 
 #include "internals.h"
Index: linux-next/kernel/softirq.c
===================================================================
--- linux-next.orig/kernel/softirq.c
+++ linux-next/kernel/softirq.c
@@ -24,6 +24,8 @@
 #include <linux/ftrace.h>
 #include <linux/smp.h>
 #include <linux/tick.h>
+
+#define CREATE_TRACE_POINTS
 #include <trace/events/irq.h>
 
 #include <asm/irq.h>

Re: Next April 24: [S390] allmodconfig build failure (trace/events)

[Ingo Molnar]

* Heiko Carstens <heiko.carstens@de.ibm.com> wrote:

> On Wed, 29 Apr 2009 15:21:39 +0530
> Sachin Sant <sachinp@in.ibm.com> wrote:
> > Heiko Carstens wrote:
> > > On Fri, 24 Apr 2009 09:25:33 +0200
> > > Ingo Molnar <mingo@elte.hu> wrote:
> > >> * Sachin Sant <sachinp@in.ibm.com> wrote:
> > >>> Today's next tree build(s390 allmodconfig) failed with
> > >>>
> > >>> kernel/built-in.o: In function `trace_softirq_entry'
> > >>> include/trace/events/irq.h:42: undefined reference to  
> > >>> `'
> > >>> include/trace/events/irq.h:42: undefined reference to  
> > >>> `__tracepoint_softirq_entry'
> > >>> kernel/built-in.o: In function `trace_softirq_exit':
> > >>> include/trace/events/irq.h:48: undefined reference to  
> > >>> `__tracepoint_softirq_exit'
> > >>> include/trace/events/irq.h:48: undefined reference to  
> > >>> `__tracepoint_softirq_exit'
> > >>>       
> > >> Hm, that's weird - s390 does not build kernel/softirq.o? Hm, it does 
> > >> - softirq.o is an obj-y object.
> > >
> > > s390 does build kernel/softirq.o. However it's anything but obvious to
> > > me how the tracepoint infrastructure works. Too many #ifdefs, #define's
> > > and #undefine's...
> > >
> > > I would expect that struct __tracepoint_softirq_entry somehow gets
> > > defined via one of the TRACE_FORMAT macros, no?
> > Today's next tree also has this failure. Any solution for this problem ?
> 
> Ingo, could you pick up the patch below please?

applied, thanks Heiko!

	Ingo

Re: Next April 24: [S390] allmodconfig build failure (trace/events)

[Steven Rostedt]

On Wed, 29 Apr 2009, Heiko Carstens wrote:
> 
> Subject: [PATCH] tracing: fix compile error
> 
> From: Heiko Carstens <heiko.carstens@de.ibm.com>
> 
> "tracing: create automated trace defines" causes this compile error on s390:
> 
> kernel/built-in.o: In function `__do_softirq':
> (.text+0x1c680): undefined reference to `__tracepoint_softirq_entry'
> 
> This happens because the definitions of the softirq tracepoints were moved
> from kernel/softirq.c to kernel/irq/handle.c. Since s390 doesn't support
> generic hardirqs handle.c doesn't get compiled and the definitions are
> missing.
> So move the tracepoints to softirq.c again.

Nice catch!

Acked-by: Steven Rostedt <rostedt@goodmis.org>

-- Steve