This patch improves oprofile callgraphs for i386/x86_64. The old
backtracing code was unable to produce kernel backtraces if the
kernel wasn't compiled with framepointers. The code now uses
dump_trace().
[ tglx: arch/x86 adaptation ]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
They were already very similar; just use the same file now.
[ tglx: arch/x86 adaptation ]
Cc: lenb@kernel.org
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
ICH3 and ICH4 have undocumented HPET capabilities. This patch enables
HPET for platforms based around these ICHs.
Tested on various ICH3 and ICH4 platforms.
Because HPET is not officially documented for ICH3/4 and may not have
been validated by chipset folks, we're on thin ice here. I'd recommend
testing this patch in -hrt or -mm for a while and wait for
success/failure reports before feeding it upstream.
tglx: depends on the force_hpet command line option !
Signed-off-by: Udo A. Steinberg <us15@os.inf.tu-dresden.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds quirks to force enable HPET on Via VT8235 and
VT8237 chipsets. The datasheet for 8237 documents HPET
functionality (although wrongly) whereas HPET is undocumented
for 8235.
Tested on A7V880 (8237) and K7VT4A+ (8235) boards.
tglx: depends on the force_hept commandline option
Signed-off-by: Udo A. Steinberg <us15@os.inf.tu-dresden.de>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
add force_hpet boot option.
(this will be useful to make the forced-enable quirks depend on.)
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
don't zero pad addresses in segfault message. Matches the other trap
messages. This leaves some more space for the new file name.
[ mingo: arch/x86 adaptation ]
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This makes x86-64's ia32 code use the new linux/elfcore-compat.h, reducing
some hand-copied duplication.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Andi Kleen <ak@suse.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Old debugging code that is not really needed anymore. If someone
wants it it would be better replaced with a systemtap script or
kprobe.
This avoids a potential cache miss during page fault processing.
[ mingo: arch/x86 adaptation ]
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Simple cosmetic update for the cs5536 reboot fixup; define the MSR that's used
for rebooting in geode.h, and use the define.
Signed-off-by: Andres Salomon <dilinger@debian.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
x86 NUMA kernels crash in the scheduler setup code if "nosmp" or
"maxcpus=0" is passed on the boot command line:
| Brought up 1 CPUs
| BUG: unable to handle kernel NULL pointer dereference at virtual address 00000000
| printing eip: c011f0b5 *pde = 00000000
| Oops: 0000 [#1] SMP
|
| Pid: 1, comm: swapper Not tainted (2.6.23 #67)
| EIP: 0060:[<c011f0b5>] EFLAGS: 00010246 CPU: 0
| EIP is at sd_degenerate+0x35/0x40
the reason is sloppy spaghetti code in smpboot_32.c that resulted in a
missing map_cpu_to_logical_apicid() call - which also had the side-effect
of setting up the cpu_2_node[] entry for the lone CPU. That resulted in
node_to_cpumask(0) resulting in 00000000 - confusing the sched-domains
setup code.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Appended patch fixes an oops while changing the vsyscall sysctl.
I am sure no one tested this code before integrating into mainline :(
BTW, using ioremap() in vsyscall_sysctl_change() to get the virtual
address of a kernel symbol sounds like an over kill.. I wonder if we
can define a simple __va_vsymbol() which will return directly the
kernel direct mapping. comments in the code which says gcc has trouble
with __va(__pa()) sounds bogus to me. __pa() on a vsyscall address will
not work anyhow :(
And also, the whole nop out syscall in vsyscall page infrastructure
(vsyscall_sysctl_change()) is added to make some attacks difficult,
and yet I don't see this nop out being done by default. This area
requires more cleanups?
Fix an oops with __pa_vsymbol(). VSYSCALL_FIRST_PAGE is a fixmap index.
We want the starting virtual address of the vsyscall page and not the index.
[ mingo: arch/x86 adaptation ]
Reported-by: Yanmin Zhang <yanmin.zhang@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
While we were reviewing pageattr_32/64.c for unification,
Thomas Gleixner noticed the following serious SMP bug in
global_flush_tlb():
down_read(&init_mm.mmap_sem);
list_replace_init(&deferred_pages, &l);
up_read(&init_mm.mmap_sem);
this is SMP-unsafe because list_replace_init() done on two CPUs in
parallel can corrupt the list.
This bug has been introduced about a year ago in the 64-bit tree:
commit ea7322decb
Author: Andi Kleen <ak@suse.de>
Date: Thu Dec 7 02:14:05 2006 +0100
[PATCH] x86-64: Speed and clean up cache flushing in change_page_attr
down_read(&init_mm.mmap_sem);
- dpage = xchg(&deferred_pages, NULL);
+ list_replace_init(&deferred_pages, &l);
up_read(&init_mm.mmap_sem);
the xchg() based version was SMP-safe, but list_replace_init() is not.
So this "cleanup" introduced a nasty bug.
why this bug never become prominent is a mystery - it can probably be
explained with the (still) relative obscurity of the x86_64 architecture.
the safe fix for now is to write-lock init_mm.mmap_sem.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Get rid of sparse related warnings from places that use integer as NULL
pointer.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Ian Kent <raven@themaw.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
msr_class_cpu_callback() can be marked __cpuinit, being the notifier callback
for a __cpuinitdata notifier_block. So can be marked msr_device_create() too,
called only from the newly-__cpuinit msr_class_cpu_callback() or from
__init-marked msr_init().
Signed-off-by: Satyam Sharma <satyam@infradead.org>
Cc: Andi Kleen <ak@suse.de>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Fix resource leakage in error case within detect_cache_attributes()
- Don't register hotcpu notifier when cache_add_dev() returns error
- Introduce cache_dev_map cpumask to track whether cache interface for
CPU is successfully added by cache_add_dev() or not.
cache_add_dev() may fail with out of memory error. In order to
avoid cache_remove_dev() with that uninitialized cache interface when
CPU_DEAD event is delivered we need to have the cache_dev_map cpumask.
(We cannot change cache_add_dev() from CPU_ONLINE event handler
to CPU_UP_PREPARE event handler. Because cache_add_dev() needs
to do cpuid and store the results with its CPU online.)
[nix.or.die@googlemail.com: fix a section mismatch warning]
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Andi Kleen <ak@suse.de>
Cc: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Gabriel Craciunescu <nix.or.die@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Clear kobject in percpu device_mce before calling sysdev_register() with
Because mce_create_device() may fail and it leaves kobject filled with
junk. It will be the problem when mce_create_device() will be called
next time.
- Fix error handling in mce_create_device()
Error handling should not do sysdev_remove_file() with not yet added
attributes.
- Don't register hotcpu notifier when mce_create_device() returns error
- Do mce_create_device() in CPU_UP_PREPARE instead of CPU_ONLINE
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Andi Kleen <ak@suse.de>
Cc: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On platforms that copy sys_tz into the vdso (currently only x86_64, soon to
include powerpc), it is possible for the vdso to get out of sync if a user
calls (admittedly unusual) settimeofday(NULL, ptr).
This patch adds a hook for architectures that set
CONFIG_GENERIC_TIME_VSYSCALL to ensure when sys_tz is updated they can also
updatee their copy in the vdso.
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Tony Luck <tony.luck@intel.com>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use temporary page tables for the kernel text mapping during hibernation
restore on x86_64.
Without the patch, the original boot kernel's page tables that represent the
kernel text mapping are used while the core of the image kernel is being
restored. However, in principle, if the boot kernel is not identical to the
image kernel, the location of these page tables in the image kernel need not
be the same, so we should create a safe copy of the kernel text mapping prior
to restoring the core of the image kernel.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since we already pass the address of restore_registers() in the image header,
we can also pass the value of the CR3 register from before the hibernation in
the same way. This will allow us to avoid using init_level4_pgt page tables
during the restore.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make it possible to restore a hibernation image on x86_64 with the help of a
kernel different from the one in the image.
The idea is to split the core restoration code into two separate parts and to
place each of them in a different page. The first part belongs to the boot
kernel and is executed as the last step of the image kernel's memory
restoration procedure. Before being executed, it is relocated to a safe page
that won't be overwritten while copying the image kernel pages.
The final operation performed by it is a jump to the second part of the core
restoration code that belongs to the image kernel and has just been restored.
This code makes the CPU switch to the image kernel's page tables and restores
the state of general purpose registers (including the stack pointer) from
before the hibernation.
The main issue with this idea is that in order to jump to the second part of
the core restoration code the boot kernel needs to know its address.
However, this address may be passed to it in the image header. Namely, the
part of the image header previously used for checking if the version of the
image kernel is correct can be replaced with some architecture specific data
that will allow the boot kernel to jump to the right address within the image
kernel. These data should also be used for checking if the image kernel is
compatible with the boot kernel (as far as the memory restroration procedure
is concerned). It can be done, for example, with the help of a "magic" value
that has to be equal in both kernels, so that they can be regarded as
compatible.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes old debugging stuff, that should be no longer neccessary. It
accessed VGA hardware (which may not be ready at this point), and used LEDs
at port 80 for debugging.
Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
make clean failed to delete a few files in
x86/kernel. This is because kbuild does not
see the correct/full kernel/Makefile.
As a workaround until the Makefiles are merged specify
the files to be deleted in the common Makefile.
Reported by Mike Galbraith <efault@gmx.de>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Fix rebuild of kernel when there is no changes.
This happened for i386.
Using make V=2 hinted that the output files were
not assigned to targets - fixed by this patch.
Reported by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch:
- makes .gitignore files visible to git
- makes arch/x86/kernel/vsyscall_32.lds and arch/i386/boot invisible
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
I can't see the reason ". = VDSO_PRELINK + 0x900;" was ever there in
the linker script for the x86_64 vDSO. I can't find anything that
depends on this magic offset, or that should care at all about the
particular location of of the .data section (all from vvar.c) in the
vDSO image. If it is really desireable to place .data at 0x900, then it
should be after all the other sections so they fill in the space up to
0x900.
This removes the 0x900 magic and cleans up the output sections generally
in the vDSO linker script. This saves a few hundred bytes in the size
of the vDSO file, bringing it back well under 4kb total so that its vma
only needs one page.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
convert mm_context_t semaphore to a mutex.
Signed-off-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Add support for and use the multi-byte NOPs recently documented to be
available on all PentiumPro and later processors.
This patch only applies cleanly on top of the "x86: misc.
constifications" patch sent earlier.
[ tglx: arch/x86 adaptation ]
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
arch/x86/kernel/alternative.c | 23 ++++++++++++++++++++++-
include/asm-x86/processor_32.h | 22 ++++++++++++++++++++++
include/asm-x86/processor_64.h | 22 ++++++++++++++++++++++
3 files changed, 66 insertions(+), 1 deletion(-)
Normally we will have two segment not connected pin pin0, and pin after
15...
So we need to print out "not connected\n" for previous segment, before
printing out connected pins info...
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
It doesn't seem to make sense to hide these, even if their counts
can't change at the point in time they're being displayed.
[ tglx: arch/x86 adaptation ]
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Add missing IRQs and IRQ descriptions to /proc/interrupts.
/proc/interrupts is most useful when it displays every IRQ vector in use by
the system, not just those somebody thought would be interesting.
This patch inserts the following vector displays to the i386 and x86_64
platforms, as appropriate:
rescheduling interrupts
TLB flush interrupts
function call interrupts
thermal event interrupts
threshold interrupts
spurious interrupts
A threshold interrupt occurs when ECC memory correction is occuring at too
high a frequency. Thresholds are used by the ECC hardware as occasional
ECC failures are part of normal operation, but long sequences of ECC
failures usually indicate a memory chip that is about to fail.
Thermal event interrupts occur when a temperature threshold has been
exceeded for some CPU chip. IIRC, a thermal interrupt is also generated
when the temperature drops back to a normal level.
A spurious interrupt is an interrupt that was raised then lowered by the
device before it could be fully processed by the APIC. Hence the apic sees
the interrupt but does not know what device it came from. For this case
the APIC hardware will assume a vector of 0xff.
Rescheduling, call, and TLB flush interrupts are sent from one CPU to
another per the needs of the OS. Typically, their statistics would be used
to discover if an interrupt flood of the given type has been occuring.
AK: merged v2 and v4 which had some more tweaks
AK: replace Local interrupts with Local timer interrupts
AK: Fixed description of interrupt types.
[ tglx: arch/x86 adaptation ]
[ mingo: small cleanup ]
Signed-off-by: Joe Korty <joe.korty@ccur.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Tim Hockin <thockin@hockin.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Typically the oops first lines look like this:
BUG: unable to handle kernel NULL pointer dereference at virtual address 00000000
printing eip:
c049dfbd
*pde = 00000000
Oops: 0002 [#1]
PREEMPT SMP
...
Such output is gained with some ugly if (!nl) printk("\n"); code and
besides being a waste of lines, this is also annoying to read. The
following output looks better (and it is how it looks on x86_64):
BUG: unable to handle kernel NULL pointer dereference at virtual address 00000000
printing eip: c049dfbd *pde = 00000000
Oops: 0002 [#1] PREEMPT SMP
...
[ tglx: arch/x86 adaptation ]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Some BIOSes set the C1E flag only on the second core. Print a warning so
the Firmware Toolkit can check for it.
mingo: fix C1E build bug on 32-bit
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Call cache_add_dev() from cache_sysfs_init() explicitly, instead of
referencing the CPU notifier callback directly from generic startup
code. Looks cleaner (to me at least) this way, and also makes it
possible to use other tricks to replace __cpuinit{data} annotations, as
recently discussed on this list.
Signed-off-by: Satyam Sharma <satyam@infradead.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The dmi const-ification missed acer_cpu_freq_pst. Fix it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This adds a const to the definitions vvar.c makes, so that the vdso_*
variables go into .rodata instead of .data. This is essentially a
cosmetic change, just giving the section headers in the vDSO file more
pleasing flags. These variables are read-only from the perspective of
the vDSO itself and user mode, even though the contents of the DSO image
were adjusted at boot.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Now that we check for translation enabled/disabled based on the presence
of the IOMMU translation table, we can get rid of translate_phb.
Signed-off-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In x86_64 and i386 architectures most arrays that are sized using
NR_CPUS lay in local memory on node 0. Not only will most (99%?) of the
systems not use all the slots in these arrays, particularly when NR_CPUS
is increased to accommodate future very high cpu count systems, but a
number of cache lines are passed unnecessarily on the system bus when
these arrays are referenced by cpus on other nodes.
Typically, the values in these arrays are referenced by the cpu
accessing it's own values, though when passing IPI interrupts, the cpu
does access the data relevant to the targeted cpu/node. Of course, if
the referencing cpu is not on node 0, then the reference will still
require cross node exchanges of cache lines. A common use of this is
for an interrupt service routine to pass the interrupt to other cpus
local to that node.
Ideally, all the elements in these arrays should be moved to the per_cpu
data area. In some cases (such as x86_cpu_to_apicid) the array is
referenced before the per_cpu data areas are setup. In this case, a
static array is declared in the __initdata area and initialized by the
booting cpu (BSP). The values are then moved to the per_cpu area after
it is initialized and the original static array is freed with the rest
of the __initdata.
This patch:
Fix four instances where cpu_to_node is referenced by array instead of
via the cpu_to_node macro. This is preparation to moving it to the
per_cpu data area.
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
