In order to share the common code in tsc.c which does CPU Khz calibration, we
need to make an accurate value of CPU speed available to the tsc.c code. This
value loses a lot of precision in a VM because of the timing differences with
real hardware, but we need it to be as precise as possible so the guest can
make accurate time calculations with the cycle counters.
Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The custom_sched_clock hook is broken. The result from sched_clock needs to
be in nanoseconds, not in CPU cycles. The TSC is insufficient for this
purpose, because TSC is poorly defined in a virtual environment, and mostly
represents real world time instead of scheduled process time (which can be
interrupted without notice when a virtual machine is descheduled).
To make the scheduler consistent, we must expose a different nature of time,
that is scheduled time. So deprecate this custom_sched_clock hack and turn it
into a paravirt-op, as it should have been all along. This allows the tsc.c
code which converts cycles to nanoseconds to be shared by all paravirt-ops
backends.
It is unfortunate to add a new paravirt-op, but this is a very distinct
abstraction which is clearly different for all virtual machine
implementations, and it gets rid of an ugly indirect function which I
ashamedly admit I hacked in to try to get this to work earlier, and then even
got in the wrong units.
Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Critical bugfixes for the VMI-Timer code.
1) Do not setup a one shot alarm if we are keeping the periodic alarm
armed. Additionally, since the periodic alarm can be run at a lower rate
than HZ, let's fixup the guard to the no-idle-hz mode appropriately. This
fixes the bug where the no-idle-hz mode might have a higher interrupt rate
than the non-idle case.
2) The interrupt handler can no longer adjust xtime due to nested lock
acquisition. Drop this. We don't need to check for wallclock time at
every tick, it can be done in userspace instead.
3) Add a bypass to disable noidle operation. This is useful as a last
minute workaround, or testing measure.
4) The code to skip the IO_APIC timer testing (no_timer_check) should be
conditional on IO_APIC, not SMP, since UP kernels can have this configured
in as well.
Signed-off-by: Dan Hecht <dhecht@vmware.com>
Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When it goes to free1_out, dev->dma_mem has not been freed.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When removing set_native_irq I missed the fact that it was
called in a couple of places that were compiled even when
SMP support is disabled. And since the irq_desc[].affinity
field only exists in SMP things broke.
Thanks to Simon Arlott <simon@arlott.org> for spotting this.
There are a couple of ways to fix this but the simplest one
is to just remove the assignments. The affinity field is only
used to display a value to the user, and nothing on either i386
or x86_64 reads it or depends on it being any particlua value,
so skipping the assignment is safe. The assignment that
is being removed is just for the initial affinity value before
the user explicitly sets it. The irq_desc array initializes
this field to CPU_MASK_ALL so the field is initialized to
a reasonable value in the SMP case without being set.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit aeeddc1435, which was
half-baked and broken. It just resulted in compile errors, since
cpufreq_register_driver() still changes the 'driver_data' by setting
bits in the flags field. So claiming it is 'const' _really_ doesn't
work.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch replaces all instances of "set_native_irq_info(irq, mask)"
with "irq_desc[irq].affinity = mask". The latter form is clearer
uses fewer abstractions, and makes access to this field uniform
accross different architectures.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 2ff2d3d747.
Uwe Bugla reports that he cannot mount a floppy drive any more, and Jiri
Slaby bisected it down to this commit.
Benjamin LaHaise also points out that this is a big hot-path, and that
interrupt delivery while idle is very common and should not go through
all these expensive gyrations.
Fix up conflicts in arch/i386/kernel/apic.c and arch/i386/kernel/irq.c
due to other unrelated irq changes.
Cc: Stephane Eranian <eranian@hpl.hp.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Uwe Bugla <uwe.bugla@gmx.de>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (25 commits)
Documentation/kernel-docs.txt update.
arch/cris: typo in KERN_INFO
Storage class should be before const qualifier
kernel/printk.c: comment fix
update I/O sched Kconfig help texts - CFQ is now default, not AS.
Remove duplicate listing of Cris arch from README
kbuild: more doc. cleanups
doc: make doc. for maxcpus= more visible
drivers/net/eexpress.c: remove duplicate comment
add a help text for BLK_DEV_GENERIC
correct a dead URL in the IP_MULTICAST help text
fix the BAYCOM_SER_HDX help text
fix SCSI_SCAN_ASYNC help text
trivial documentation patch for platform.txt
Fix typos concerning hierarchy
Fix comment typo "spin_lock_irqrestore".
Fix misspellings of "agressive".
drivers/scsi/a100u2w.c: trivial typo patch
Correct trivial typo in log2.h.
Remove useless FIND_FIRST_BIT() macro from cardbus.c.
...
Now that disable_irq() defaults to delayed-disable semantics, the IRQ_DISABLED
flag is not needed anymore.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Never mask interrupts immediately upon request. Disabling interrupts in
high-performance codepaths is rare, and on the other hand this change could
recover lost edges (or even other types of lost interrupts) by conservatively
only masking interrupts after they happen. (NOTE: with this change the
highlevel irq-disable code still soft-disables this IRQ line - and if such an
interrupt happens then the IRQ flow handler keeps the IRQ masked.)
Mark i8529A controllers as 'never loses an edge'.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In preparation for supporting generic timekeeping, this patch cleans up
x86-64's use of vxtime.hpet_address, changing it to just hpet_address as is
also used in i386. This is necessary since the vxtime structure will be going
away.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@muc.de>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The NMI watchdog implementation assumes that the local APIC timer interrupt is
happening. This assumption is not longer true when high resolution timers and
dynamic ticks come into play, as they may switch off the local APIC timer
completely. Take the PIT/HPET interrupts into account too, to avoid false
positives.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@suse.de>
Cc: Zachary Amsden <zach@vmware.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Rohit Seth <rohitseth@google.com>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The local apic timer calibration has two problem cases:
1. The calibration is based on readout of the PIT/HPET timer to detect the
wrap of the periodic tick. It happens that a box gets stuck in the
calibration loop due to a PIT with a broken readout function.
2. CoreDuo boxen show a sporadic PIT runs too slow defect, which results
in a wrong lapic calibration. The PIT goes back to normal operation once
the lapic timer is switched to periodic mode.
Both are existing and unfixed problems in the current upstream kernel and
prevent certain laptops and other systems from booting Linux.
Rework the code to address both problems:
- Make the calibration interrupt driven. This removes the wait_timer_tick
magic hackery from lapic.c and time_hpet.c. The clockevents framework
allows easy substitution of the global tick event handler for the
calibration. This is more accurate than monitoring jiffies. At this point
of the boot process, nothing disturbes the interrupt delivery, so the
results are very accurate.
- Verify the calibration against the PM timer, when available by using the
early access function. When the measured calibration period is outside of
an one percent window, then the lapic timer calibration is adjusted to the
pm timer result.
- Verify the calibration by running the lapic timer with the calibration
handler. Disable lapic timer in case of deviation.
This also removes the "synchronization" of the local apic timer to the global
tick. This synchronization never worked, as there is no way to synchronize
PIT(HPET) and local APIC timer. The synchronization by waiting for the tick
just alignes the local APIC timer for the first events, but later the events
drift away due to the different clocks. Removing the "sync" is just
randomizing the asynchronous behaviour at setup time.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Zachary Amsden <zach@vmware.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Rohit Seth <rohitseth@google.com>
Cc: Andi Kleen <ak@suse.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add clockevent drivers for i386: lapic (local) and PIT/HPET (global). Update
the timer IRQ to call into the PIT/HPET driver's event handler and the
lapic-timer IRQ to call into the lapic clockevent driver. The assignement of
timer functionality is delegated to the core framework code and replaces the
compile and runtime evalution in do_timer_interrupt_hook()
Use the clockevents broadcast support and implement the lapic_broadcast
function for ACPI.
No changes to existing functionality.
[ kdump fix from Vivek Goyal <vgoyal@in.ibm.com> ]
[ fixes based on review feedback from Arjan van de Ven <arjan@infradead.org> ]
Cleanups-from: Adrian Bunk <bunk@stusta.de>
Build-fixes-from: Andrew Morton <akpm@osdl.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The apic code is quite unstructured and missing a lot of comments.
- Restructure the code into helper functions, timer, setup/shutdown,
interrupt and power management blocks.
- Fixup comments.
- Namespace fixups
- Inline helpers for version and is_integrated
- Combine the ack_bad_irq functions
No functional changes.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Zachary Amsden <zach@vmware.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Rohit Seth <rohitseth@google.com>
Cc: Andi Kleen <ak@suse.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Allow early access to the power management timer by exposing the verified read
function and providing a helper function which checks the pmtmr_ioport
variable and returns either the pm timer readout or 0 in case the pm timer is
not available.
Create a new header file and replace also the ifdef'ed extern definition in
arch/i386/kernel/acpi/boot.c
This is a preperatory patch for the rework of the local apic timer
calibration.
No functional changes.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The Geode can safely use the TSC for highres, since:
1) Does not support frequency scaling,
2) The TSC _does_ count when the CPU is halted. Furthermore, the Geode
supports a mode called "suspension on halt", where Suspend mode (which
interacts with the power management states) is entered. TSC counting
during suspend mode is controlled by bit 8 of the Bus Controller
Configuration Register #0 (thanks Tom!).
3) no SMP :)
Check if "RTSC counts during suspension" and remove the requirement for
verification, so the clocksource code can safely select it as an timesource
for the highres timers subsystem.
Signed-off-by: Marcelo Tosatti <marcelo@kvack.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The TSC needs to be verified against another clocksource. Instead of using
hardwired assumptions of available hardware, provide a generic verification
mechanism. The verification uses the best available clocksource and handles
the usability for high resolution timers / dynticks of the clocksource which
needs to be verified.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The clocksource code allows direct updates of the rating of a given
clocksource now. Change TSC unstable tracking to use this interface and
remove the update callback.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Using a flag filed allows to encode more than one information into a variable.
Preparatory patch for the generic clocksource verification.
[mingo@elte.hu: convert vmitime.c to the new clocksource flag]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
make the TSC synchronization code more robust, and unify it between x86_64 and
i386.
The biggest change is the removal of the 'fix up TSCs' code on x86_64 and
i386, in some rare cases it was /causing/ time-warps on SMP systems.
The new code only checks for TSC asynchronity - and if it can prove a
time-warp (if it can observe the TSC going backwards when going from one CPU
to another within a critical section), then the TSC clock-source is turned
off.
The TSC synchronization-checking code also got moved into a separate file.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Enqueue clocksources in rating order to make selection of the clocksource
easier. Also check the match with an user override at enqueue time.
Preparatory patch for the generic clocksource verification.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The delayed work code in arch/i386/kernel/tsc.c is an unused leftover of the
GTOD conversion. Remove it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a flag so we can prevent the irq balancing of an interrupt. Move the
bits, so we have room for more :)
Necessary for the ability to setup clocksources more flexible (e.g. use the
different HPET channels per CPU)
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Start using v2 version of Longhaul when available. It provides
voltage scaling and can use ACPI C3 state. That's curious. CPU
will not change frequency on ACPI C3 when v1 is in use, but it will
when v2 is used. Driver will return max frequency all the time if
this isn't true for all processors. There is strange thing with
mobile voltage. Looks like only Nehemiah (C3-M) supports it.
Earlier processors have different mobile VRM (in docs), but I can't
find any which is using it. Looks like all are using VRM 8.5. So
fail for non Nehemiah with mobile VRM.
Signed-off-by: Rafal Bilski <rafalbilski@interia.pl>
Signed-off-by: Dave Jones <davej@redhat.com>
Solution for small, but nasty bug: access beyond end of f_table for C7 brand.
Signed-off-by: Rafal Bilski <rafalbilski@interia.pl>
Signed-off-by: Dave Jones <davej@redhat.com>
After updating several machines to 2.6.20, I can't boot anymore the single
one of them that supports the NX bit and is configured as a 32-bit system.
My understanding is that the VDSO changes in 2.6.20-rc7 were not fully
cooked, in that with that config option enabled VDSO_SYM(x) now equals
x, meaning that an address in the fixmap area is now being passed to
apps via AT_SYSINFO. However, the page is mapped with PAGE_READONLY
rather than PAGE_READONLY_EXEC.
I'm not certain whether having app code go through the fixmap area is
intended, but in case it is here is the simple patch that makes things work
again.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
When I implemented the DECLARE_PER_CPU(var) macros, I was careful that
people couldn't use "var" in a non-percpu context, by prepending
percpu__. I never considered that this would allow them to overload
the same name for a per-cpu and a non-percpu variable.
It is only one of many horrors in the i386 boot code, but let's rename
the non-perpcu cpu_gdt_descr to early_gdt_descr (not boot_gdt_descr,
that's something else...)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andi Kleen <ak@suse.de>
===================================================================
The current code simply calls "start_kernel" directly if we're under a
hypervisor and no paravirt_ops backend wants us, because paravirt.c
registers that as a backend.
This was always a vain hope; start_kernel won't get far without setup.
It's also impossible for paravirt_ops backends which don't sit in the
arch/i386/kernel directory: they can't link before paravirt.o anyway.
Keep it simple: if we pass all the registered paravirt probes, BUG().
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andi Kleen <ak@suse.de>
The old Cyrix 5520 CPU detection code relied upon the PCI layer setup being
done earlier than the CPU setup, which is no longer true. Fortunately we
know that if the processor is a MediaGX we can do type 1 pci config
accesses to check the companion chip. We thus do those directly and from
this find the 5520 and implement the workarounds for the timer problem
Original report from takada@mbf.nifty.com, I sent a proposed patch which
Takara then corrected, tested and sent back to the list on 10th January.
Submitting for merging as it seems to have been missed
AK: Changed to use pci-direct.h and fix warning for !CONFIG_PCI (later
AK: originally from akpm)
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: <takada@mbf.nifty.com>
Cc: Jordan Crouse <jordan.crouse@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Fix bogus warning
linux/arch/i386/kernel/cpu/transmeta.c:12: warning: ‘cpu_freq’ may be used uninitialized in this function
Signed-off-by: Andi Kleen <ak@suse.de>
Fix bogus gcc warning
linux/arch/i386/kernel/microcode.c:387: warning: ‘new_mc’ may be used uninitialized in this function
Signed-off-by: Andi Kleen <ak@suse.de>
Just various new acronyms. The new popcnt bit is in the middle
of Intel space. This looks a little weird, but I've been assured
it's ok.
Also I fixed RDTSCP for i386 which was at the wrong place.
For i386 and x86-64.
Signed-off-by: Andi Kleen <ak@suse.de>
Original code doesn't write back to CCR4 register. This patch reflects a
value of a register.
Cc: Jordan Crouse <jordan.crouse@amd.com>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andi Kleen <ak@suse.de>
