Re: [PATCH ] printk: add module parameter console_suspend to control console_suspend_enabled

[Yanmin Zhang <yanmin_zhang@linux.intel.com>]

On Tue, 2011-08-09 at 17:59 +0800, Dave Young wrote:
> Hi,
> 
> On Tue, Aug 9, 2011 at 4:55 PM, Yanmin Zhang
> <yanmin_zhang@linux.intel.com> wrote:
> > On Tue, 2011-08-09 at 16:01 +0800, Dave Young wrote:
> >> On Tue, Aug 9, 2011 at 11:09 AM, Yanmin Zhang
> >> <yanmin_zhang@linux.intel.com> wrote:
> >> > We are enabling some power features on medfield. To test suspend-2-RAM
> >> > conveniently, we need turn on/off console_suspend_enabled frequently.
> >> >
> >> > Below patch adds a module parameter, so users could change it by:
> >> > /sys/module/printk/parameters/console_suspend_enabled
> >>
> >> What about change name to no_console_suspend? Or it will be weird if
> >> boot kernel with both no_console_suspend and
> >> printk.console_suspend_enabled set.
> > Thanks for the comments. How about changing the name to console_suspend?
> > If changing it to no_console_suspend, we can't map the input to console_suspend_enabled
> > directly.
> 
> How about use module_param_cb instead of module_param_named?
Thanks for the pointer. Indeed, we could use module_param_cb to support the
input/output parsing. Is it too complicated to use it here? It's better
to keep simple. The new name console_suspend is clearer than old name.

> 
> >
> > Below is the new patch.
> >
> > ---
> >
> > We are enabling some power features on medfield. To test suspend-2-RAM
> > conveniently, we need turn on/off console_suspend_enabled frequently.
> >
> > Below patch adds a module parameter, so users could change it by:
> > /sys/module/printk/parameters/console_suspend
> >
> > Signed-off-by: Yanmin Zhang <yanmin_zhang@linux.intel.com>
> >
> > ---
> >  kernel/printk.c |    2 ++
> >  1 files changed, 2 insertions(+), 0 deletions(-)
> >
> > diff --git a/kernel/printk.c b/kernel/printk.c
> > index 37dff34..1decef6 100644
> > --- a/kernel/printk.c
> > +++ b/kernel/printk.c
> > @@ -1106,6 +1106,8 @@ static int __init console_suspend_disable(char *str)
> >        return 1;
> >  }
> >  __setup("no_console_suspend", console_suspend_disable);
> > +module_param_named(console_suspend, console_suspend_enabled,
> > +               bool, S_IRUGO | S_IWUSR);
> >
> >  /**
> >  * suspend_console - suspend the console subsystem
> > --