Re: [PATCH] x86: Construct 32 bit boot time page tables in native format.

Len Brown
2008-02-01T22:57:38Z

On Friday 01 February 2008 09:54, Ingo Molnar wrote:
>
> * Rafael J. Wysocki <rjw@sisk.pl> wrote:
>
> > > no strong preference here - pick the one you like best and send a
> > > patch please :-)
> >
> > Here you go, but I think it falls into the ACPI category.
>
> agreed - Len, would you mind to pick this patch up?

This won't work as written -- for the ACPI code doesn't currently optimize
for the HIBERNATE && ! SUSPEND case, and so both code paths are under ACPI_SLEEP.

While some day there may be a justification to make that optimization,
this isn't the day, and this isn't the patch.

So Rafael and I talked about it and decided to go with the simpler
patch below -- which I'll push.

thanks,
-Len

---
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index da524fb..f2f36f8 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -423,23 +423,23 @@ static void __init pagetable_init(void)
paravirt_pagetable_setup_done(pgd_base);
}

-#if defined(CONFIG_HIBERNATION) || defined(CONFIG_ACPI)
+#ifdef CONFIG_ACPI_SLEEP
/*
- * Swap suspend & friends need this for resume because things like the intel-agp
+ * ACPI suspend needs this for resume, because things like the intel-agp
* driver might have split up a kernel 4MB mapping.
*/
-char __nosavedata swsusp_pg_dir[PAGE_SIZE]
+char swsusp_pg_dir[PAGE_SIZE]
__attribute__ ((aligned(PAGE_SIZE)));

static inline void save_pg_dir(void)
{
memcpy(swsusp_pg_dir, swapper_pg_dir, PAGE_SIZE);
}
-#else
+#else /* !CONFIG_ACPI_SLEEP */
static inline void save_pg_dir(void)
{
}
-#endif
+#endif /* !CONFIG_ACPI_SLEEP */

void zap_low_mappings(void)
{