Messages in this thread | | | Date | Wed, 30 Jul 2008 20:09:39 +0300 | From | Adrian Bunk <> | Subject | Re: [PATCH 1/2] Export get_user_pages_fast |
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On Wed, Jul 30, 2008 at 10:03:55AM -0700, Andrew Morton wrote: > On Wed, 30 Jul 2008 18:47:36 +0300 Adrian Bunk <bunk@kernel.org> wrote: > > > On Wed, Jul 30, 2008 at 03:35:23AM -0700, Andrew Morton wrote: > > > On Wed, 30 Jul 2008 14:38:55 +1000 Rusty Russell <rusty@rustcorp.com.au> wrote: > > > > > > > After all, it was made for lguest wasn't it? Still think it should be > > > > called get_current_pages() though. > > > > > > > > Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> > > > > --- > > > > arch/x86/mm/gup.c | 2 ++ > > > > 1 file changed, 2 insertions(+) > > > > > > > > diff -r cb465381f6d5 arch/x86/mm/gup.c > > > > --- a/arch/x86/mm/gup.c Wed Jul 30 10:18:44 2008 +1000 > > > > +++ b/arch/x86/mm/gup.c Wed Jul 30 14:22:53 2008 +1000 > > > > @@ -8,6 +8,7 @@ > > > > #include <linux/mm.h> > > > > #include <linux/vmstat.h> > > > > #include <linux/highmem.h> > > > > +#include <linux/module.h> > > > > > > > > #include <asm/pgtable.h> > > > > > > > > @@ -296,3 +303,4 @@ slow_irqon: > > > > return ret; > > > > } > > > > } > > > > +EXPORT_SYMBOL_GPL(get_user_pages_fast); > > > > > > A regularly-occurring problem with an export like this is that someone > > > writes a driver and tests it on x86, then the driver explodes on an > > > architecture which didn't export the same symbol. > > > > > > So a better implementation might be to put > > > > > > #ifdef CONFIG_HAVE_GET_USER_PAGES_FAST > > > EXPORT_SYMBOL_GPL(get_user_pages_fast); > > > #endif > > > > > > into generic code somewhere. > > > > How would that help? > > It would fix the problem which I described.
The export would still only be available on x86 since no other arch would define CONFIG_HAVE_GET_USER_PAGES_FAST.
Or what do I miss?
cu Adrian
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"Is there not promise of rain?" Ling Tan asked suddenly out of the darkness. There had been need of rain for many days. "Only a promise," Lao Er said. Pearl S. Buck - Dragon Seed
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