kernel_optimize_test/arch/um
Russell King 4b3073e1c5 MM: Pass a PTE pointer to update_mmu_cache() rather than the PTE itself
On VIVT ARM, when we have multiple shared mappings of the same file
in the same MM, we need to ensure that we have coherency across all
copies.  We do this via make_coherent() by making the pages
uncacheable.

This used to work fine, until we allowed highmem with highpte - we
now have a page table which is mapped as required, and is not available
for modification via update_mmu_cache().

Ralf Beache suggested getting rid of the PTE value passed to
update_mmu_cache():

  On MIPS update_mmu_cache() calls __update_tlb() which walks pagetables
  to construct a pointer to the pte again.  Passing a pte_t * is much
  more elegant.  Maybe we might even replace the pte argument with the
  pte_t?

Ben Herrenschmidt would also like the pte pointer for PowerPC:

  Passing the ptep in there is exactly what I want.  I want that
  -instead- of the PTE value, because I have issue on some ppc cases,
  for I$/D$ coherency, where set_pte_at() may decide to mask out the
  _PAGE_EXEC.

So, pass in the mapped page table pointer into update_mmu_cache(), and
remove the PTE value, updating all implementations and call sites to
suit.

Includes a fix from Stephen Rothwell:

  sparc: fix fallout from update_mmu_cache API change

  Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-20 16:41:46 +00:00
..
drivers Unrot uml mconsole a bit 2010-01-14 09:05:26 -05:00
include MM: Pass a PTE pointer to update_mmu_cache() rather than the PTE itself 2010-02-20 16:41:46 +00:00
kernel Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-12-15 09:02:01 -08:00
os-Linux includecheck fix: um, helper.c 2009-09-20 15:59:20 +05:30
scripts
sys-i386 elf: kill USE_ELF_CORE_DUMP 2009-12-16 07:20:12 -08:00
sys-ia64
sys-ppc elf: kill USE_ELF_CORE_DUMP 2009-12-16 07:20:12 -08:00
sys-x86_64 elf: kill USE_ELF_CORE_DUMP 2009-12-16 07:20:12 -08:00
defconfig
Kconfig.char
Kconfig.common
Kconfig.debug
Kconfig.net
Kconfig.rest
Kconfig.um
Kconfig.x86
Makefile kbuild: move asm-offsets.h to include/generated 2009-12-12 13:08:14 +01:00
Makefile-i386
Makefile-ia64
Makefile-os-Linux
Makefile-ppc
Makefile-skas
Makefile-x86_64