linux-toradex.git/include/asm-x86/xen, branch v2.6.27.27

removed unused #include 's

2008-08-23T19:14:12+00:00

This patch lets the files using linux/version.h match the files that
#include it.

Signed-off-by: Adrian Bunk 
Signed-off-by: Linus Torvalds

x86: rename PTE_MASK to PTE_PFN_MASK

2008-07-22T08:43:44+00:00

Rusty, in his peevish way, complained that macros defining constants
should have a name which somewhat accurately reflects the actual
purpose of the constant.

Aside from the fact that PTE_MASK gives no clue as to what's actually
being masked, and is misleadingly similar to the functionally entirely
different PMD_MASK, PUD_MASK and PGD_MASK, I don't really see what the
problem is.

But if this patch silences the incessent noise, then it will have
achieved its goal (TODO: write test-case).

Signed-off-by: Jeremy Fitzhardinge 
Cc: Rusty Russell 
Signed-off-by: Ingo Molnar

xen: implement Xen-specific spinlocks

2008-07-16T09:15:53+00:00

The standard ticket spinlocks are very expensive in a virtual
environment, because their performance depends on Xen's scheduler
giving vcpus time in the order that they're supposed to take the
spinlock.

This implements a Xen-specific spinlock, which should be much more
efficient.

The fast-path is essentially the old Linux-x86 locks, using a single
lock byte.  The locker decrements the byte; if the result is 0, then
they have the lock.  If the lock is negative, then locker must spin
until the lock is positive again.

When there's contention, the locker spin for 2^16[*] iterations waiting
to get the lock.  If it fails to get the lock in that time, it adds
itself to the contention count in the lock and blocks on a per-cpu
event channel.

When unlocking the spinlock, the locker looks to see if there's anyone
blocked waiting for the lock by checking for a non-zero waiter count.
If there's a waiter, it traverses the per-cpu "lock_spinners"
variable, which contains which lock each CPU is waiting on.  It picks
one CPU waiting on the lock and sends it an event to wake it up.

This allows efficient fast-path spinlock operation, while allowing
spinning vcpus to give up their processor time while waiting for a
contended lock.

[*] 2^16 iterations is threshold at which 98% locks have been taken
according to Thomas Friebel's Xen Summit talk "Preventing Guests from
Spinning Around".  Therefore, we'd expect the lock and unlock slow
paths will only be entered 2% of the time.

Signed-off-by: Jeremy Fitzhardinge 
Cc: Jens Axboe 
Cc: Peter Zijlstra 
Cc: Christoph Lameter 
Cc: Petr Tesarik 
Cc: Virtualization 
Cc: Xen devel 
Cc: Thomas Friebel 
Cc: Nick Piggin 
Signed-off-by: Ingo Molnar

xen64: implement 64-bit update_descriptor

2008-07-16T09:05:09+00:00

64-bit hypercall interface can pass a maddr in one argument rather
than splitting it.

Signed-off-by: Jeremy Fitzhardinge 
Cc: Stephen Tweedie 
Cc: Eduardo Habkost 
Cc: Mark McLoughlin 
Signed-off-by: Ingo Molnar

Xen64: HYPERVISOR_set_segment_base() implementation

2008-07-16T09:03:31+00:00

Signed-off-by: Eduardo Habkost 
Signed-off-by: Jeremy Fitzhardinge 
Cc: Stephen Tweedie 
Cc: Mark McLoughlin 
Signed-off-by: Ingo Molnar

xen64: register callbacks in arch-independent way

2008-07-16T09:03:01+00:00

Use callback_op hypercall to register callbacks in a 32/64-bit
independent way (64-bit doesn't need a code segment, but that detail
is hidden in XEN_CALLBACK).

Signed-off-by: Jeremy Fitzhardinge 
Cc: Stephen Tweedie 
Cc: Eduardo Habkost 
Cc: Mark McLoughlin 
Signed-off-by: Ingo Molnar

xen64: use arbitrary_virt_to_machine for xen_set_pmd

2008-07-16T09:01:17+00:00

When building initial pagetables in 64-bit kernel the pud/pmd pointer may
be in ioremap/fixmap space, so we need to walk the pagetable to look up the
physical address.

Signed-off-by: Jeremy Fitzhardinge 
Cc: Stephen Tweedie 
Cc: Eduardo Habkost 
Cc: Mark McLoughlin 
Signed-off-by: Ingo Molnar

xen64: add extra pv_mmu_ops

2008-07-16T08:57:16+00:00

We need extra pv_mmu_ops for 64-bit, to deal with the extra level of
pagetable.

Signed-off-by: Jeremy Fitzhardinge 
Cc: Stephen Tweedie 
Cc: Eduardo Habkost 
Cc: Mark McLoughlin 
Signed-off-by: Ingo Molnar

xen64: fix calls into hypercall page

2008-07-16T08:57:00+00:00

The 64-bit calling convention for hypercalls uses different registers
from 32-bit.  Annoyingly, gcc's asm syntax doesn't have a way to
specify one of the extra numeric reigisters in a constraint, so we
must use explicitly placed register variables.  Given that we have to
do it for some args, may as well do it for all.

Also fix syntax gcc generates for the call instruction itself.  We
need a plain direct call, but the asm expansion which works on 32-bit
generates a rip-relative addressing mode in 64-bit, which is treated
as an indirect call.  The alternative is to pass the hypercall page
offset into the asm, and have it add it to the hypercall page start
address to generate the call.

Signed-off-by: Jeremy Fitzhardinge 
Cc: Stephen Tweedie 
Cc: Eduardo Habkost 
Cc: Mark McLoughlin 
Signed-off-by: Ingo Molnar

xen: fix 64-bit hypercall variants

2008-07-16T08:56:46+00:00

64-bit guests can pass 64-bit quantities in a single argument,
so fix up the hypercalls.

Signed-off-by: Jeremy Fitzhardinge 
Cc: Stephen Tweedie 
Cc: Eduardo Habkost 
Cc: Mark McLoughlin 
Signed-off-by: Ingo Molnar