Re: [RESEND][PATCH 1/2] stacktrace: add saved stack traces to backtrace self-test

[Ingo Molnar <mingo@elte.hu>]

* Vegard Nossum <vegard.nossum@gmail.com> wrote:

> On Fri, Jun 27, 2008 at 9:20 PM, Ingo Molnar <mingo@elte.hu> wrote:
> >
> > FYI, it needed the fixlet below.
> >
> >        Ingo
> >
> 
> Oh. I'm sorry :-(
> 
> (I'll admit that I've never worked with modules before. I'll try to 
> remember now.)

i too work with bzImages most of the time. They are convenient 
single-file objects that are easy to distribute and easy to use, and 
they also have no Linux-distribution-flavor dependencies. (module load 
order can be influenced by things like /etc/modprobe.conf and other 
details - make reproduction harder and testing less conclusive, etc.)

> > ------------->
> > commit 7bcebd2e3ee8435e2ff0f674a409f46961fda3cc
> > Author: Ingo Molnar <mingo@elte.hu>
> > Date:   Fri Jun 27 21:20:17 2008 +0200
> >
> >    stacktrace: export print_stack_trace and save_stack_trace
> >
> >    fix:
> >
> >    ERROR: "print_stack_trace" [kernel/backtracetest.ko] undefined!
> >    ERROR: "save_stack_trace" [kernel/backtracetest.ko] undefined!
> >
> >    Signed-off-by: Ingo Molnar <mingo@elte.hu>
> >
> >    Conflicts:
> >
> >    Signed-off-by: Ingo Molnar <mingo@elte.hu>
> >
> > diff --git a/arch/x86/kernel/stacktrace.c b/arch/x86/kernel/stacktrace.c
> > index c28c342..b7b483b 100644
> > --- a/arch/x86/kernel/stacktrace.c
> > +++ b/arch/x86/kernel/stacktrace.c
> > @@ -74,10 +74,4 @@ void save_stack_trace(struct stack_trace *trace)
> >        if (trace->nr_entries < trace->max_entries)
> >                trace->entries[trace->nr_entries++] = ULONG_MAX;
> >  }
> > -
> > -void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
> > -{
> > -       dump_trace(tsk, NULL, NULL, 0, &save_stack_ops_nosched, trace);
> > -       if (trace->nr_entries < trace->max_entries)
> > -               trace->entries[trace->nr_entries++] = ULONG_MAX;
> > -}
> 
> Why is this removed, though? (It seems unrelated, and that's a useful 
> function.)

that was an oversight - thanks - fixed it - updated commit below.

	Ingo

---------------->
commit a73d1be0974856741a258928966b8a03ae6bb74f
Author: Ingo Molnar <mingo@elte.hu>
Date:   Fri Jun 27 21:20:17 2008 +0200

    stacktrace: fix modular build, export print_stack_trace and save_stack_trace
    
    fix:
    
    ERROR: "print_stack_trace" [kernel/backtracetest.ko] undefined!
    ERROR: "save_stack_trace" [kernel/backtracetest.ko] undefined!
    
    Signed-off-by: Ingo Molnar <mingo@elte.hu>
    
    and fix:
    
      Building modules, stage 2.
      MODPOST 376 modules
    ERROR: "print_stack_trace" [kernel/backtracetest.ko] undefined!
    make[1]: *** [__modpost] Error 1
    
    Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/stacktrace.c b/arch/x86/kernel/stacktrace.c
index c28c342..a03e7f6 100644
--- a/arch/x86/kernel/stacktrace.c
+++ b/arch/x86/kernel/stacktrace.c
@@ -74,6 +74,7 @@ void save_stack_trace(struct stack_trace *trace)
 	if (trace->nr_entries < trace->max_entries)
 		trace->entries[trace->nr_entries++] = ULONG_MAX;
 }
+EXPORT_SYMBOL_GPL(save_stack_trace);
 
 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
 {
@@ -81,3 +82,4 @@ void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
 	if (trace->nr_entries < trace->max_entries)
 		trace->entries[trace->nr_entries++] = ULONG_MAX;
 }
+EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
diff --git a/kernel/stacktrace.c b/kernel/stacktrace.c
index 7eaea9d..94b527e 100644
--- a/kernel/stacktrace.c
+++ b/kernel/stacktrace.c
@@ -6,6 +6,7 @@
  *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
  */
 #include <linux/sched.h>
+#include <linux/module.h>
 #include <linux/kallsyms.h>
 #include <linux/stacktrace.h>
 
@@ -21,4 +22,5 @@ void print_stack_trace(struct stack_trace *trace, int spaces)
 		print_ip_sym(trace->entries[i]);
 	}
 }
+EXPORT_SYMBOL_GPL(print_stack_trace);