Re: [PATCH 05/37] kdb: core for kgdb back end

[Andi Kleen <andi@xxxxxxxxxxxxxx>]

Jason Wessel <jason.wessel@xxxxxxxxxxxxx> writes:

I remember going with kaos through all the code
outside kdb/ in his own patch and for nearly all hooks
outside we found some way to eliminate them. 

I think a lot of this is here too.

>  
> +#ifdef       CONFIG_KGDB_KDB
> +/* Like meminfo_proc_show() but without the locks and using kdb_printf() */
> +void kdb_meminfo_proc_show(void)

Are there even any locks in meminfo_proc_show()? I don't see any on a quick 
look.
Ah or is that only for swap_info? That could be a flag or perhaps that
access can be even made lockless (it looks like it could)

I guess a better way would be to have a kdb specific seq file implementation
and then just use the normal function, instead of copying everything.

>  void get_vmalloc_info(struct vmalloc_info *vmi)
>  {
>       struct vm_struct *vma;
>       unsigned long free_area_size;
>       unsigned long prev_end;
> +#ifdef CONFIG_KGDB_KDB
> +     int get_lock = !KDB_IS_RUNNING();
> +#else
> +#define      get_lock 1
> +#endif
> +

A standard way to do such would be a __get_vmalloc_info with the 
lock in the caller

Didn't read everything in this gigantic patch.

-Andi

-- 
ak@xxxxxxxxxxxxxxx -- Speaking for myself only.