user-mode-linux-devel

[uml-devel] [PATCH v3 3/3] um: enable trace irqflags support

[Thomas M. <th...@m3...>]

Add TRACE_IRQFLAGS_SUPPORT to UML.
This enables LOCKDEP_SUPPORT and TRACING_SUPPORT.

Signed-off-by: Thomas Meyer <th...@m3...>
---
diff --git a/arch/um/Kconfig.common b/arch/um/Kconfig.common
index 87bc868..6a33c3a 100644
--- a/arch/um/Kconfig.common
+++ b/arch/um/Kconfig.common
@@ -28,10 +28,9 @@ config PCI
 config PCMCIA
 	bool
 
-# Yet to do!
 config TRACE_IRQFLAGS_SUPPORT
 	bool
-	default n
+	default y
 
 config LOCKDEP_SUPPORT
 	bool
diff --git a/arch/um/include/asm/irqflags.h b/arch/um/include/asm/irqflags.h
index c780d8a..c5b636e 100644
--- a/arch/um/include/asm/irqflags.h
+++ b/arch/um/include/asm/irqflags.h
@@ -34,9 +34,9 @@ static inline unsigned long arch_local_irq_save(void)
 	return flags;
 }
 
-static inline bool arch_irqs_disabled(void)
+static inline int arch_irqs_disabled_flags(unsigned long flags)
 {
-	return arch_local_save_flags() == 0;
+	return flags == 0;
 }
 
 #endif
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index f1efeee..fc188d8 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -251,6 +251,9 @@ static struct notifier_block panic_exit_notifier = {
 
 void uml_finishsetup(void)
 {
+#ifdef CONFIG_LOCKDEP
+	lockdep_init();
+#endif
 	atomic_notifier_chain_register(&panic_notifier_list,
 				       &panic_exit_notifier);
 

Re: [uml-devel] [PATCH v3 3/3] um: enable trace irqflags support

[Geert U. <ge...@li...>]

On Sun, Oct 19, 2014 at 5:14 PM, Thomas Meyer <th...@m3...> wrote:
> --- a/arch/um/kernel/um_arch.c
> +++ b/arch/um/kernel/um_arch.c
> @@ -251,6 +251,9 @@ static struct notifier_block panic_exit_notifier = {
>
>  void uml_finishsetup(void)
>  {
> +#ifdef CONFIG_LOCKDEP
> +       lockdep_init();
> +#endif

The #ifdef is not needed. include/linux/lockdep.h provides a dummy
definition if !CONFIG_LOCKDEP.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@li...

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

Re: [uml-devel] [PATCH v3 3/3] um: enable trace irqflags support

[Daniel W. <sa...@0x...>]

----- Original Message -----
> From: "Thomas Meyer" <th...@m3...>
> To: "user-mode-linux-devel" <use...@li...>
> Sent: Sunday, October 19, 2014 4:14:13 PM
> Subject: [uml-devel] [PATCH v3 3/3] um: enable trace irqflags support
> 
> Add TRACE_IRQFLAGS_SUPPORT to UML.
> This enables LOCKDEP_SUPPORT and TRACING_SUPPORT.


FYI: I'm currently working on porting ftrace() support to
uml. It will take another week or two since I don't have enough
time to debug, and it isn't stable yet (read as is panic()ing randomly)


> 
> Signed-off-by: Thomas Meyer <th...@m3...>
> ---
> diff --git a/arch/um/Kconfig.common b/arch/um/Kconfig.common
> index 87bc868..6a33c3a 100644
> --- a/arch/um/Kconfig.common
> +++ b/arch/um/Kconfig.common
> @@ -28,10 +28,9 @@ config PCI
>  config PCMCIA
>  	bool
>  
> -# Yet to do!
>  config TRACE_IRQFLAGS_SUPPORT
>  	bool
> -	default n
> +	default y
>  
>  config LOCKDEP_SUPPORT
>  	bool
> diff --git a/arch/um/include/asm/irqflags.h
> b/arch/um/include/asm/irqflags.h
> index c780d8a..c5b636e 100644
> --- a/arch/um/include/asm/irqflags.h
> +++ b/arch/um/include/asm/irqflags.h
> @@ -34,9 +34,9 @@ static inline unsigned long
> arch_local_irq_save(void)
>  	return flags;
>  }
>  
> -static inline bool arch_irqs_disabled(void)
> +static inline int arch_irqs_disabled_flags(unsigned long flags)
>  {
> -	return arch_local_save_flags() == 0;
> +	return flags == 0;
>  }
>  
>  #endif

I'm not sure if this is correct. I'd rather would have another function
implemented instead of removing the check for disabled irqs.


cheers,

daniel