David Miller wrote: > From: Michal Simek <michal.simek@xxxxxxxxxxxxx> > Date: Wed, 08 Jul 2009 20:03:27 +0200 > > >> David Miller wrote: >> >>> From: Michal Simek <michal.simek@xxxxxxxxxxxxx> >>> Date: Wed, 08 Jul 2009 19:03:11 +0200 >>> >>> >>> >>>> When I call mmap for that open file with pointer to calloc place >>>> (first parameter, + length zero) it should be one tlb invalidation >>>> for calloc and new tlb which connect open file. We check it and we >>>> don't have any tlb invalidation that's why I think that kernel do >>>> different thigs. Or is it there any copying? Or anything different? >>>> >>>> >>> There is no need to tlb flush the calloc area unless that memory area >>> is actually touched by the user application and thus the page is >>> faulted in. >>> >>> >> That calloc area is filled by any value (in that test). Is it mean that >> for this case when calloc area is touched >> there must be tlb invalidation + remapping? >> > > Yes, if the calloc area is written to by the application, there > should be a tlb flush when the mmap() overrides that virtual region > with a different mapping. > Can you please point me to any code which exactly do this? (for example file mm/mmap.c line from ... to ... ) Thanks, Michal -- Michal Simek, Ing. (M.Eng) PetaLogix - Linux Solutions for a Reconfigurable World w: www.petalogix.com p: +61-7-30090663,+42-0-721842854 f: +61-7-30090663 -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
