linux.git/include/asm-i386/processor.h, branch v2.6.20

[PATCH] x86: fix PDA variables to work during boot

2007-01-23T03:39:36+00:00

The current PDA code, which went in in post 2.6.19 has a flaw in that it
doesn't correctly cycle the GDT and %GS segment through the boot PDA,
the CPU PDA and finally the per-cpu PDA.

The bug generally doesn't show up if the boot CPU id is zero, but
everything falls apart for a non zero boot CPU id.  The basically kills
voyager which is perfectly capable of doing non zero CPU id boots, so
voyager currently won't boot without this.

The fix is to be careful and actually do the GDT setups correctly.

Signed-off-by: James Bottomley 
Cc: Andi Kleen 
Cc: Jeremy Fitzhardinge 
Cc: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] i386: cpu_detect extraction

2006-12-07T01:14:08+00:00

Both lhype and Xen want to call the core of the x86 cpu detect code before
calling start_kernel.

(extracted from larger patch)

AK: folded in start_kernel header patch

Signed-off-by: Jeremy Fitzhardinge 
Signed-off-by: Rusty Russell 
Signed-off-by: Andi Kleen 
Cc: Jeremy Fitzhardinge 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton

[PATCH] paravirt: Patch inline replacements for paravirt intercepts

2006-12-07T01:14:08+00:00

It turns out that the most called ops, by several orders of magnitude,
are the interrupt manipulation ops.  These are obvious candidates for
patching, so mark them up and create infrastructure for it.

The method used is that the ops structure has a patch function, which
is called for each place which needs to be patched: this returns a
number of instructions (the rest are NOP-padded).

Usually we can spare a register (%eax) for the binary patched code to
use, but in a couple of critical places in entry.S we can't: we make
the clobbers explicit at the call site, and manually clobber the
allowed registers in debug mode as an extra check.

And:

Don't abuse CONFIG_DEBUG_KERNEL, add CONFIG_DEBUG_PARAVIRT.

And:

AK:  Fix warnings in x86-64 alternative.c build

And:

AK: Fix compilation with defconfig

And:

^From: Andrew Morton 

Some binutlises still like to emit references to __stop_parainstructions and
__start_parainstructions.

And:

AK: Fix warnings about unused variables when PARAVIRT is disabled.

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

[PATCH] paravirt: header and stubs for paravirtualisation

2006-12-07T01:14:07+00:00

Create a paravirt.h header for all the critical operations which need to be
replaced with hypervisor calls, and include that instead of defining native
operations, when CONFIG_PARAVIRT.

This patch does the dumbest possible replacement of paravirtualized
instructions: calls through a "paravirt_ops" structure.  Currently these are
function implementations of native hardware: hypervisors will override the ops
structure with their own variants.

All the pv-ops functions are declared "fastcall" so that a specific
register-based ABI is used, to make inlining assember easier.

And:

+From: Andy Whitcroft 

The paravirt ops introduce a 'weak' attribute onto memory_setup().
Code ordering leads to the following warnings on x86:

    arch/i386/kernel/setup.c:651: warning: weak declaration of
                `memory_setup' after first use results in unspecified behavior

Move memory_setup() to avoid this.

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

[PATCH] i386: Retrieve CLFLUSH size from CPUID

2006-12-07T01:14:05+00:00

Also report it in /proc/cpuinfo similar to x86-64.

Needed for followon patch

Signed-off-by: Andi Kleen

[PATCH] i386: Use %gs as the PDA base-segment in the kernel

2006-12-07T01:14:02+00:00

This patch is the meat of the PDA change.  This patch makes several related
changes:

1: Most significantly, %gs is now used in the kernel.  This means that on
   entry, the old value of %gs is saved away, and it is reloaded with
   __KERNEL_PDA.

2: entry.S constructs the stack in the shape of struct pt_regs, and this
   is passed around the kernel so that the process's saved register
   state can be accessed.

   Unfortunately struct pt_regs doesn't currently have space for %gs
   (or %fs). This patch extends pt_regs to add space for gs (no space
   is allocated for %fs, since it won't be used, and it would just
   complicate the code in entry.S to work around the space).

3: Because %gs is now saved on the stack like %ds, %es and the integer
   registers, there are a number of places where it no longer needs to
   be handled specially; namely context switch, and saving/restoring the
   register state in a signal context.

4: And since kernel threads run in kernel space and call normal kernel
   code, they need to be created with their %gs == __KERNEL_PDA.

Signed-off-by: Jeremy Fitzhardinge 
Signed-off-by: Andi Kleen 
Cc: Chuck Ebbert <76306.1226@compuserve.com>
Cc: Zachary Amsden 
Cc: Jan Beulich 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton

[PATCH] i386: Initialize the per-CPU data area

2006-12-07T01:14:02+00:00

When a CPU is brought up, a PDA and GDT are allocated for it.  The GDT's
__KERNEL_PDA entry is pointed to the allocated PDA memory, so that all
references using this segment descriptor will refer to the PDA.

This patch rearranges CPU initialization a bit, so that the GDT/PDA are set up
as early as possible in cpu_init().  Also for secondary CPUs, GDT+PDA are
preallocated and initialized so all the secondary CPU needs to do is set up
the ldt and load %gs.  This will be important once smp_processor_id() and
current use the PDA.

In all cases, the PDA is set up in head.S, before a CPU starts running C code,
so the PDA is always available.

Signed-off-by: Jeremy Fitzhardinge 
Signed-off-by: Andi Kleen 
Cc: Chuck Ebbert <76306.1226@compuserve.com>
Cc: Zachary Amsden 
Cc: Jan Beulich 
Cc: Andi Kleen 
Cc: James Bottomley 
Cc: Matt Tolentino 
Signed-off-by: Andrew Morton

ACPI: Processor native C-states using MWAIT

2006-10-14T04:35:39+00:00

Intel processors starting with the Core Duo support
support processor native C-state using the MWAIT instruction.
Refer: Intel Architecture Software Developer's Manual
http://www.intel.com/design/Pentium4/manuals/253668.htm

Platform firmware exports the support for Native C-state to OS using
ACPI _PDC and _CST methods.
Refer: Intel Processor Vendor-Specific ACPI: Interface Specification
http://www.intel.com/technology/iapc/acpi/downloads/302223.htm

With Processor Native C-state, we use 'MWAIT' instruction on the processor
to enter different C-states (C1, C2, C3).  We won't use the special IO
ports to enter C-state and no SMM mode etc required to enter C-state.
Overall this will mean better C-state support.

One major advantage of using MWAIT for all C-states is, with this and
"treat interrupt as break event" feature of MWAIT, we can now get accurate
timing for the time spent in C1, C2, ..  states.

Signed-off-by: Venkatesh Pallipadi 
Signed-off-by: Andrew Morton 
Signed-off-by: Len Brown

[PATCH] x86: roll all the cpuid asm into one __cpuid call

2006-09-26T15:48:55+00:00

It's a little neater, and also means only one place to patch for
paravirtualization.

Signed-off-by: Rusty Russell 
Signed-off-by: Jeremy Fitzhardinge 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] i386: move phys_proc_id and cpu_core_id to cpuinfo_x86

2006-06-28T00:32:37+00:00

Move the phys_core_id and cpu_core_id to cpuinfo_x86 structure.  Similar
patch for x86_64 is already accepted by Andi earlier this week.

[akpm@osdl.org: fix warning]
Signed-off-by: Rohit Seth 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds