Re: [PATCH 1/5] dynamic logical partitioning infrastructure

[Nathan Fontenot]

Brian King wrote:
> Nathan Fontenot wrote:
> > +#include <linux/kernel.h>
> > +#include <linux/kref.h>
> > +#include <linux/notifier.h>
> > +#include <linux/proc_fs.h>
> > +#include <linux/spinlock.h>
> > +
> > +#include <asm/prom.h>
> > +#include <asm/machdep.h>
> > +#include <asm/uaccess.h>
> > +#include <asm/rtas.h>
> > +#include <asm/pSeries_reconfig.h>
> > +
> > +#define CFG_CONN_WORK_SIZE    4096
> > +static char workarea[CFG_CONN_WORK_SIZE];
> > +spinlock_t workarea_lock;
>
> This can be:
>
> static DEFINE_SPINLOCK(workarea_lock);
>
> Then you can get rid of the runtime initializer.

Good catch,  I will fix it in the updated patches.

> > +
> > +int release_drc(u32 drc_index)
> > +{
> > +    int dr_status, rc;
> > +
> > +    rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
> > +               DR_ENTITY_SENSE, drc_index);
> > +    if (rc || dr_status != DR_ENTITY_PRESENT)
> > +        return -1;
> > +
> > +    rc = rtas_set_indicator(ISOLATION_STATE, drc_index, ISOLATE);
> > +    if (rc)
> > +        return -1;
> > +
> > +    rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
> > +    if (rc) {
> > +        rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
> > +        return -1;
> > +    }
>
> Is there a better return value here that might be more descriptive than -1?

Yes,  I could return the rtas error code to the user to allow the caller to
evaluate it if they wanted to.  For what I am doing I am only concerned with
success/failure so I did not deal with returning anything other than -1.

I'll update the next patch to return the rtas error for failures and 0
for success.

> > +
> > +    return 0;
> > +}
> > +
> > +static int pseries_dlpar_init(void)
> > +{
> > +    spin_lock_init(&workarea_lock);
> > +
> > +    if (!machine_is(pseries))
> > +        return 0;
>
> What's the point of this if check if you return 0 either way?

Yes, it seems a bit odd here, but in patches later in this series I
add additional initialization steps after the machine_is() check
such that it makes sense to bail out here if the check fails.

> > +
> > +    return 0;
> > +}
> > +__initcall(pseries_dlpar_init);
>
>
> > Index: powerpc/arch/powerpc/platforms/pseries/reconfig.c
> > ===================================================================
> > --- powerpc.orig/arch/powerpc/platforms/pseries/reconfig.c    2009-09-11
> > 12:43:39.000000000 -0500
> > +++ powerpc/arch/powerpc/platforms/pseries/reconfig.c    2009-09-11
> > 12:51:52.000000000 -0500
> > @@ -95,7 +95,7 @@
> >     return parent;
> > }
> >
> > -static BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);
> > +struct blocking_notifier_head pSeries_reconfig_chain =
> > BLOCKING_NOTIFIER_INIT(pSeries_reconfig_chain);
>
> Can't this just be?
>
> BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);

I think I tried this and was having issues,  I don't remember what they
were though.  I will try to fix this in the updated patch.

-Nathan Fontenot
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/