Commit graph

406 commits

Author SHA1 Message Date
Al Viro
2b8232ce51 minimal build fixes for uml (fallout from x86 merge)
a) include/asm-um/arch can't just point to include/asm-$(SUBARCH) now
 b) arch/{i386,x86_64}/crypto are merged now
 c) subarch-obj needed changes
 d) cpufeature_64.h should pull "cpufeature_32.h", not <asm/cpufeature_32.h>
    since it can be included from asm-um/cpufeature.h
 e) in case of uml-i386 we need CONFIG_X86_32 for make and gcc, but not
    for Kconfig
 f) sysctl.c shouldn't do vdso_enabled for uml-i386 (actually, that one
    should be registered from corresponding arch/*/kernel/*, with ifdef
    going away; that's a separate patch, though).

With that and with Stephen's patch ("[PATCH net-2.6] uml: hard_header fix")
we have uml allmodconfig building both on i386 and amd64.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-13 09:57:15 -07:00
Rusty Russell
7075bc816c KVM: Use standard CR8 flags, and fix TPR definition
Intel manual (and KVM definition) say the TPR is 4 bits wide.  Also fix
CR8_RESEVED_BITS typo.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13 10:18:19 +02:00
Avi Kivity
81fe96bde7 i386: Expose IOAPIC register definitions even if CONFIG_X86_IO_APIC is not set
KVM reuses the IOAPIC register definitions, and needs them even if the
host is not compiled with IOAPIC support.  Move the #ifdef below so that only
the IOAPIC variables and functions are protected, and the register definitions
are available to all.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-10-13 10:18:17 +02:00
Nick Piggin
b6c7347fff x86: optimise barriers
According to latest memory ordering specification documents from Intel
and AMD, both manufacturers are committed to in-order loads from
cacheable memory for the x86 architecture.  Hence, smp_rmb() may be a
simple barrier.

Also according to those documents, and according to existing practice in
Linux (eg.  spin_unlock doesn't enforce ordering), stores to cacheable
memory are visible in program order too.  Special string stores are safe
-- their constituent stores may be out of order, but they must complete
in order WRT surrounding stores.  Nontemporal stores to WB memory can go
out of order, and so they should be fenced explicitly to make them
appear in-order WRT other stores.  Hence, smp_wmb() may be a simple
barrier.

    http://developer.intel.com/products/processor/manuals/318147.pdf
    http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/24593.pdf

In userspace microbenchmarks on a core2 system, fence instructions range
anywhere from around 15 cycles to 50, which may not be totally
insignificant in performance critical paths (code size will go down
too).

However the primary motivation for this is to have the canonical barrier
implementation for x86 architecture.

smp_rmb on buggy pentium pros remains a locked op, which is apparently
required.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-12 18:41:21 -07:00
Nick Piggin
4071c71855 x86: fix IO write barrier
wmb() on x86 must always include a barrier, because stores can go out of
order in many cases when dealing with devices (eg. WC memory).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-12 18:41:21 -07:00
Thomas Gleixner
96a388de5d i386/x86_64: move headers to include/asm-x86
Move the headers to include/asm-x86 and fixup the
header install make rules

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-11 11:20:03 +02:00