linux.git/include/asm-generic/pgtable.h, branch v2.6.22-rc4

[S390] split page_test_and_clear_dirty.

2007-04-27T14:01:46+00:00

The page_test_and_clear_dirty primitive really consists of two
operations, page_test_dirty and the page_clear_dirty. The combination
of the two is not an atomic operation, so it makes more sense to have
two separate operations instead of one.
In addition to the improved readability of the s390 version of
SetPageUptodate, it now avoids the page_test_dirty operation which is
an insert-storage-key-extended (iske) instruction which is an expensive
operation.

Signed-off-by: Martin Schwidefsky

[PATCH] Proper fix for highmem kmap_atomic functions for VMI for 2.6.21

2007-04-09T02:47:55+00:00

Since lazy MMU batching mode still allows interrupts to enter, it is
possible for interrupt handlers to try to use kmap_atomic, which fails when
lazy mode is active, since the PTE update to highmem will be delayed.  The
best workaround is to issue an explicit flush in kmap_atomic_functions
case; this is the only way nested PTE updates can happen in the interrupt
handler.

Thanks to Jeremy Fitzhardinge for noting the bug and suggestions on a fix.

This patch gets reverted again when we start 2.6.22 and the bug gets fixed
differently.

Signed-off-by: Zachary Amsden 
Cc: Andi Kleen 
Cc: Jeremy Fitzhardinge 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] i386: paravirt CPU hypercall batching mode

2007-02-13T12:26:21+00:00

The VMI ROM has a mode where hypercalls can be queued and batched.  This turns
out to be a significant win during context switch, but must be done at a
specific point before side effects to CPU state are visible to subsequent
instructions.  This is similar to the MMU batching hooks already provided.
The same hooks could be used by the Xen backend to implement a context switch
multicall.

To explain a bit more about lazy modes in the paravirt patches, basically, the
idea is that only one of lazy CPU or MMU mode can be active at any given time.
 Lazy MMU mode is similar to this lazy CPU mode, and allows for batching of
multiple PTE updates (say, inside a remap loop), but to avoid keeping some
kind of state machine about when to flush cpu or mmu updates, we just allow
one or the other to be active.  Although there is no real reason a more
comprehensive scheme could not be implemented, there is also no demonstrated
need for this extra complexity.

Signed-off-by: Zachary Amsden 
Signed-off-by: Andi Kleen 
Cc: Andi Kleen 
Cc: Jeremy Fitzhardinge 
Cc: Rusty Russell 
Cc: Chris Wright 
Signed-off-by: Andrew Morton

[PATCH] paravirt: remove set pte atomic

2006-10-01T07:39:34+00:00

Now that ptep_establish has a definition in PAE i386 3-level paging code, the
only paging model which is insane enough to have multi-word hardware PTEs
which are not efficient to set atomically, we can remove the ghost of
set_pte_atomic from other architectures which falesly duplicated it, and
remove all knowledge of it from the generic pgtable code.

set_pte_atomic is now a private pte operator which is specific to i386

Signed-off-by: Zachary Amsden 
Cc: Rusty Russell 
Cc: Jeremy Fitzhardinge 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] paravirt: lazy mmu mode hooks.patch

2006-10-01T07:39:33+00:00

Implement lazy MMU update hooks which are SMP safe for both direct and shadow
page tables.  The idea is that PTE updates and page invalidations while in
lazy mode can be batched into a single hypercall.  We use this in VMI for
shadow page table synchronization, and it is a win.  It also can be used by
PPC and for direct page tables on Xen.

For SMP, the enter / leave must happen under protection of the page table
locks for page tables which are being modified.  This is because otherwise,
you end up with stale state in the batched hypercall, which other CPUs can
race ahead of.  Doing this under the protection of the locks guarantees the
synchronization is correct, and also means that spurious faults which are
generated during this window by remote CPUs are properly handled, as the page
fault handler must re-check the PTE under protection of the same lock.

Signed-off-by: Zachary Amsden 
Signed-off-by: Jeremy Fitzhardinge 
Cc: Rusty Russell 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] paravirt: pte clear not present

2006-10-01T07:39:33+00:00

Change pte_clear_full to a more appropriately named pte_clear_not_present,
allowing optimizations when not-present mapping changes need not be reflected
in the hardware TLB for protected page table modes.  There is also another
case that can use it in the fremap code.

Signed-off-by: Zachary Amsden 
Signed-off-by: Jeremy Fitzhardinge 
Cc: Rusty Russell 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] x86: trivial pgtable.h ASSEMBLY move

2006-09-26T15:48:56+00:00

Parsing generic pgtable.h in assembler is simply crazy.  None of this file is
needed in assembler code, and C inline functions and structures routine break
one or more different compiles.

Signed-off-by: Zachary Amsden 
Signed-off-by: Rusty Russell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[SPARC64]: Fix D-cache corruption in mremap

2006-06-02T00:47:25+00:00

If we move a mapping from one virtual address to another,
and this changes the virtual color of the mapping to those
pages, we can see corrupt data due to D-cache aliasing.

Check for and deal with this by overriding the move_pte()
macro.  Set things up so that other platforms can cleanly
override the move_pte() macro too.

Signed-off-by: David S. Miller

[PATCH] fix remaining missing includes

2005-11-07T15:53:41+00:00

Fix more include file problems that surfaced since I submitted the previous
fix-missing-includes.patch.  This should now allow not to include sched.h
from module.h, which is done by a followup patch.

Signed-off-by: Tim Schmielau 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] mm: update comments to pte lock

2005-10-30T04:40:42+00:00

Updated several references to page_table_lock in common code comments.

Signed-off-by: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds