fix code to access CMOS rtc registers so that it does not use inb_p and
outb_p routines, which are deprecated. Extensive research on all known
CMOS RTC chipset timing shows that there is no need for a delay in
accessing the registers of these chips even on old machines. These chipa
are never on an expansion bus, but have always been "motherboard"
resources, either in the processor chipset or explicitly on the
motherboard, and they are not part of the ISA/LPC or PCI buses, so
delays should not be based on bus timing. The reason to fix it:
1) port 80 writes often hang some laptops that use ENE EC chipsets,
esp. those designed and manufactured by Quanta for HP;
2) RTC accesses are timing sensitive, and extra microseconds may matter;
3) the new "io_delay" function is calibrated by expansion bus timing needs,
thus is not appropriate for access to CMOS rtc registers.
Signed-off-by: David P. Reed <dpreed@reed.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Replace the hardcoded list of initialization functions for each CPU
vendor by a list in an ELF section, which is read at initialization in
arch/x86/kernel/cpu/cpu.c to fill the cpu_devs[] array. The ELF
section, named .x86cpuvendor.init, is reclaimed after boot, and
contains entries of type "struct cpu_vendor_dev" which associates a
vendor number with a pointer to a "struct cpu_dev" structure.
This first modification allows to remove all the VENDOR_init_cpu()
functions.
This patch also removes the hardcoded calls to early_init_amd() and
early_init_intel(). Instead, we add a "c_early_init" member to the
cpu_dev structure, which is then called if not NULL by the generic CPU
initialization code. Unfortunately, in early_cpu_detect(), this_cpu is
not yet set, so we have to use the cpu_devs[] array directly.
This patch is part of the Linux Tiny project, and is needed for
further patch that will allow to disable compilation of unused CPU
support code.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
It becomes to early for ioremap, so we use early_ioremap
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ravikiran Thirumalai <kiran@scalemp.com>
Acked-by: Shai Fultheim <shai@scalemp.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Change Makefile so vsmp_64.o object is dependent
on PARAVIRT, rather than X86_VSMP
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ravikiran Thirumalai <kiran@scalemp.com>
Acked-by: Shai Fultheim <shai@scalemp.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
we don't need get that so early.
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
I found it strange that the struct sk_buff definition was found
inside the DWARF debugging sections in the generated object, so I verified
and found that there is no need for the files that bring struct sk_buff
definition into this file and verified also that sk_buff is not brought
in indirectly too, thru other headers.
I went on and removed many other unneeded includes and the end
result is:
[acme@doppio net-2.6]$ l /tmp/sys_ia32.o.before /tmp/sys_ia32.o.after
-rw-rw-r-- 1 acme acme 185240 2008-02-06 19:19 /tmp/sys_ia32.o.after
-rw-rw-r-- 1 acme acme 248328 2008-02-06 19:00 /tmp/sys_ia32.o.before
Almost 64KB only on this object file!
There were no other side effects from this change:
[acme@doppio net-2.6]$ objcopy -j "text" /tmp/sys_ia32.o.before /tmp/text.before
[acme@doppio net-2.6]$ objcopy -j "text" /tmp/sys_ia32.o.after /tmp/text.after
[acme@doppio net-2.6]$ md5sum /tmp/text.before /tmp/text.after
b7ac9b17942add68494e698e4f965d36 /tmp/text.before
b7ac9b17942add68494e698e4f965d36 /tmp/text.after
One of the complaints about using tools such as systemtap is
that one has to install the huge kernel-debuginfo package:
[acme@doppio net-2.6]$ rpm -q --qf "%{size}\n" kernel-rt-debuginfo
471737710
543867594
[acme@doppio net-2.6]$
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ian Campbell <ijc@hellion.org.uk>
Cc: Ian Campbell <ijc@hellion.org.uk>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: virtualization@lists.linux-foundation.org
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[ tglx@linutronix.de: cleanup the other structs as well ]
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The extended century readout does not solve the year 2038 problem on
32bit!
v2: Fix compilation on !ACPI, pointed out by tglx
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We assume that the RTC clock is BCD, so print a warning if it claims
to be binary.
[ tglx@linutronix.de: changed to WARN_ON - we want to know that!
If no one reports it we can remove the complete if (RTC_ALWAYS_BCD)
magic, which has RTC_ALWAYS_BCD defined to 1 since Linux 1.0 ... ]
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We know it is already after 2000. Use the year 2000 offset for both 32
and 64 bit, which removes ifdefs and the 1970 magic.
[ tglx@linutronix.de: remove 1970 magic, replace bogus commit message ]
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Change size to unsigned long, becase caller and user all used unsigned long.
Also make bad_addr take an alignment parameter.
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The AMD Fam10h CPUs support new Gigabyte page table entry for
mapping 1GB at a time. Use this for the kernel direct mapping.
Only done for 64bit because i386 does not support GB page tables.
This only applies to the data portion of the direct mapping; the
kernel text mapping stays with 2MB pages because the AMD Fam10h
microarchitecture does not support GB ITLBs and AMD recommends
against using GB mappings for code.
Can be disabled with disable_gbpages on the kernel command line
[ tglx@linutronix.de: simplify enable code ]
[ Yinghai Lu <yinghai.lu@sun.com>: boot fix on 256 GB RAM ]
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
These new controls toggle experimental support for a new CPU feature,
the straightforward extension of largepages from the pmd level to the
pud level, which allows 1GB (kernel) TLBs instead of 2MB TLBs.
Turn it off by default, as this code has not been tested well enough yet.
Use the CONFIG_DIRECT_GBPAGES=y .config option or gbpages on the
boot line can be used to enable it. If enabled in the .config then
nogbpages boot option disables it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Clean up the page table dumper (fix boundary conditions, table driven
address ranges, some formatting changes since it is no longer using
the kernel log but a separate virtual file), and generalize to 32
bits.
[ mingo@elte.hu: x86: fix the pagetable dumper ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds code to the kernel to have an (optional)
/proc/kernel_page_tables debug file that basically dumps the kernel
pagetables; this allows us kernel developers to verify that nothing fishy is
going on and that the various mappings are set up correctly. This was quite
useful in finding various change_page_attr() bugs, and is very likely to be
useful in the future as well.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: mingo@elte.hu
Cc: tglx@tglx.de
Cc: hpa@zytor.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Unify arch/x86/mm/Makefile between 32 and 64 bits.
All configuration variables that are protected by Kconfig constraints
have been put in the common part of the Makefile; however, the NUMA
files are totally different between 32 and 64 bits and are handled via
an ifdef.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Add debug information for DEBUG_PAGEALLOC to get some statistics about
the pool usage and split status.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We map a VMA for the 32-bit vDSO even when it's disabled, which is stupid.
For the 32-bit kernel it's the vdso_enabled boot parameter/sysctl
and for the 64-bit kernel it's the vdso32 boot parameter/syscall32 sysctl.
When it's disabled, we don't pass AT_SYSINFO_EHDR so processes don't use
the vDSO for anything, but we still map it. For the non-compat vDSO,
this means we're always putting an extra VMA somewhere, maybe lousing
up the control of the address space the user was hoping for.
Honor the setting by doing nothing in arch_setup_additional_pages.
[ also see: "x86 vDSO: don't use disabled vDSO for signal trampoline" ]
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If the vDSO was not mapped, don't use it as the "restorer" for a signal
handler. Whether we have a pointer in mm->context.vdso depends on what
happened at exec time, so we shouldn't check any global flags now.
Background:
Currently, every 32-bit exec gets the vDSO mapped even if it's disabled
(the process just doesn't get told about it). Because it's in fact
always there, the bug that this patch fixes cannot happen now. With
the second patch, it won't be mapped at all when it's disabled, which is
one of the things that people might really want when they disable it (so
nothing they didn't ask for goes into their address space).
The 32-bit signal handler setup when SA_RESTORER is not used refers to
current->mm->context.vdso without regard to whether the vDSO has been
disabled when the process was exec'd. This patch fixes this not to use
it when it's null, which becomes possible after the second patch. (This
never happens in normal use, because glibc's sigaction call uses
SA_RESTORER unless glibc detected the vDSO.)
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
people sometimes do crazy stuff like building really large static
arrays into their kernels or building allyesconfig kernels. Give
more space to the kernel and push modules up a bit: kernel has
512 MB and modules have 1.5 GB.
Should be enough for a few years ;-)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
http://bugzilla.kernel.org/show_bug.cgi?id=10124
this change:
commit 08f1c192c3
Author: Muli Ben-Yehuda <muli@il.ibm.com>
Date: Sun Jul 22 00:23:39 2007 +0300
x86-64: introduce struct pci_sysdata to facilitate sharing of ->sysdata
This patch introduces struct pci_sysdata to x86 and x86-64, and
converts the existing two users (NUMA, Calgary) to use it.
This lays the groundwork for having other users of sysdata, such as
the PCI domains work.
The Calgary bits are tested, the NUMA bits just look ok.
replaces pcibios_scan_root by pci_scan_bus_parented...
but in pcibios_scan_root we have a check about scanned busses.
Cc: <yakui.zhao@intel.com>
Cc: Stian Jordet <stian@jordet.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Yinghai Lu" <yhlu.kernel@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The prevent_tail_call() macro works around the problem of the compiler
clobbering argument words on the stack, which for asmlinkage functions
is the caller's (user's) struct pt_regs. The tail/sibling-call
optimization is not the only way that the compiler can decide to use
stack argument words as scratch space, which we have to prevent.
Other optimizations can do it too.
Until we have new compiler support to make "asmlinkage" binding on the
compiler's own use of the stack argument frame, we have work around all
the manifestations of this issue that crop up.
More cases seem to be prevented by also keeping the incoming argument
variables live at the end of the function. This makes their original
stack slots attractive places to leave those variables, so the compiler
tends not clobber them for something else. It's still no guarantee, but
it handles some observed cases that prevent_tail_call() did not.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch also resolves hangs on boot:
http://lkml.org/lkml/2008/2/23/263http://bugzilla.kernel.org/show_bug.cgi?id=10093
The bug was causing once-in-few-reboots 10-15 sec wait during boot on
certain laptops.
Earlier commit 40d6a14662 added
smp_call_function in cpu_idle_wait() to kick cpus that are in tickless
idle. Looking at cpu_idle_wait code at that time, code seemed to be
over-engineered for a case which is rarely used (while changing idle
handler).
Below is a simplified version of cpu_idle_wait, which just makes a dummy
smp_call_function to all cpus, to make them come out of old idle handler
and start using the new idle handler. It eliminates code in the idle
loop to handle cpu_idle_wait.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc expects all toplevel assembly to return to the original section type.
The code in alteranative.c does not do this. This caused some strange bugs
in sched-devel where code would end up in the .rodata section and when
the kernel sets the NX bit on all .rodata, the kernel would crash when
executing this code.
This patch adds a .previous marker to return the code back to the
original section.
Credit goes to Andrew Pinski for telling me it wasn't a gcc bug but a
bug in the toplevel asm code in the kernel. ;-)
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In time_cpufreq_notifier() the cpu id to act upon is held in freq->cpu. Use it
instead of smp_processor_id() in the call to set_cyc2ns_scale().
This makes the preempt_*able() unnecessary and lets set_cyc2ns_scale() update
the intended cpu's cyc2ns.
Related mail/thread: http://lkml.org/lkml/2007/12/7/130
Signed-off-by: Karsten Wiese <fzu@wemgehoertderstaat.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
revert:
| commit 47001d6033
| Author: Thomas Gleixner <tglx@linutronix.de>
| Date: Tue Apr 1 19:45:18 2008 +0200
|
| x86: tsc prevent time going backwards
it has been identified to cause suspend regression - and the
commit fixes a longstanding bug that existed before 2.6.25 was
opened - so it can wait some more until the effects are better
understood.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We handle a broken tsc these days, so no need to panic. We clear the
TSC bit when tsc_init decides it's unreliable (eg. under lguest w/ bad
host TSC), leading to bogus panic.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The commits:
commit 37a47db8d7
Author: Balaji Rao <balajirrao@gmail.com>
Date: Wed Jan 30 13:30:03 2008 +0100
x86: assign IRQs to HPET timers, fix
and
commit e3f37a54f6
Author: Balaji Rao <balajirrao@gmail.com>
Date: Wed Jan 30 13:30:03 2008 +0100
x86: assign IRQs to HPET timers
have been identified to cause a regression on some platforms due to
the assignement of legacy IRQs which makes the legacy devices
connected to those IRQs disfunctional.
Revert them.
This fixes http://bugzilla.kernel.org/show_bug.cgi?id=10382
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We already catch most of the TSC problems by sanity checks, but there
is a subtle bug which has been in the code for ever. This can cause
time jumps in the range of hours.
This was reported in:
http://lkml.org/lkml/2007/8/23/96
and
http://lkml.org/lkml/2008/3/31/23
I was able to reproduce the problem with a gettimeofday loop test on a
dual core and a quad core machine which both have sychronized
TSCs. The TSCs seems not to be perfectly in sync though, but the
kernel is not able to detect the slight delta in the sync check. Still
there exists an extremly small window where this delta can be observed
with a real big time jump. So far I was only able to reproduce this
with the vsyscall gettimeofday implementation, but in theory this
might be observable with the syscall based version as well.
CPU 0 updates the clock source variables under xtime/vyscall lock and
CPU1, where the TSC is slighty behind CPU0, is reading the time right
after the seqlock was unlocked.
The clocksource reference data was updated with the TSC from CPU0 and
the value which is read from TSC on CPU1 is less than the reference
data. This results in a huge delta value due to the unsigned
subtraction of the TSC value and the reference value. This algorithm
can not be changed due to the support of wrapping clock sources like
pm timer.
The huge delta is converted to nanoseconds and added to xtime, which
is then observable by the caller. The next gettimeofday call on CPU1
will show the correct time again as now the TSC has advanced above the
reference value.
To prevent this TSC specific wreckage we need to compare the TSC value
against the reference value and return the latter when it is larger
than the actual TSC value.
I pondered to mark the TSC unstable when the readout is smaller than
the reference value, but this would render an otherwise good and fast
clocksource unusable without a real good reason.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
David P. Reed