Move reset_lazy_tlbstate into tlb_32.c, and define noop versions of
play_dead() in process_{32,64}.c when !CONFIG_SMP.
Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
It's not even passed on to smp_call_function() anymore, since that
was removed. So kill it.
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
this patch creates tlb_32.c and tlb_64.c, with
tlb-related functions that used to live in smp*.c files.
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch moves all ipi and apic related functions
from smp_32.c to ipi.c
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
this patch moves all the functions and data structures that look
like exactly the same from smp_{32,64}.c to smp.c
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This can be safely added to i386. After that,
functions look exactly the same for both arches
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
with the hlt_works change, it is possible to have i386
and x86_64 stop_this_cpu() looking exactly the same. They
can, after that, be merged.
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
the two versions (the inner version, and the outer version, that takes
the locks) of smp_call_function_mask are made into one. With the changes,
i386 and x86_64 versions look exactly the same.
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Aviod TLB flush IPIs during C3 states by voluntary leave_mm()
before entering C3.
The performance impact of TLB flush on C3 should not be significant with
respect to C3 wakeup latency. Also, CPUs tend to flush TLB in hardware while in
C3 anyways.
On a 8 logical CPU system, running make -j2, the number of tlbflush IPIs goes
down from 40 per second to ~ 0. Total number of interrupts during the run
of this workload was ~1200 per second, which makes it ~3% savings in wakeups.
There was no measurable performance or power impact however.
[ akpm@linux-foundation.org: symbol export fixes. ]
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
fastcall is always defined to be empty, remove it from arch/x86
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
'for_each_possible_cpu(i)' when there's a _remote possibility_ of
dereferencing a non-allocated per_cpu variable involved.
All files except mm/vmstat.c are x86 arch.
Thanks to pageexec@freemail.hu for pointing this out.
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: <pageexec@freemail.hu>
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>
KVM uses smp_call_function_mask and therefor need smp_ops to be exported.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This reverts commit 6442eea937.
The patch breaks smp_ops and needs to be reverted. The solution to
allow modular build of KVM is to export smp_ops instead.
Pointed-out-by: James Bottomley
<jejb> tglx, so write out 100 times "voyager is a useful architecture" ...
<tglx> yes, Sir
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
cpu_data is currently an array defined using NR_CPUS. This means that
we overallocate since we will rarely really use maximum configured cpus.
When NR_CPU count is raised to 4096 the size of cpu_data becomes
3,145,728 bytes.
These changes were adopted from the sparc64 (and ia64) code. An
additional field was added to cpuinfo_x86 to be a non-ambiguous cpu
index. This corresponds to the index into a cpumask_t as well as the
per_cpu index. It's used in various places like show_cpuinfo().
cpu_data is defined to be the boot_cpu_data structure for the NON-SMP
case.
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Mark M. Hoffman <mhoffman@lightlink.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>
This patch converts the x86_cpu_to_apicid array to be a per cpu
variable. This saves sizeof(apicid) * NR unused cpus. Access is mostly
from startup and CPU HOTPLUG functions.
MP_processor_info() is one of the functions that require access to the
x86_cpu_to_apicid array before the per_cpu data area is setup. For this
case, a pointer to the __initdata array is initialized in setup_arch()
and removed in smp_prepare_cpus() after the per_cpu data area is
initialized.
A second change is included to change the initial array value of ARCH
i386 from 0xff to BAD_APICID to be consistent with ARCH x86_64.
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>
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>
This patch export i386 smp_call_function_mask() with EXPORT_SYMBOL().
This function is needed by KVM to call a function on a set of CPUs.
[ tglx: arch/x86 adaptation ]
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Make globally leave_mm visible, specifically so that Xen can use it to
shoot-down lazy uses of cr3.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
No other architecture calls check_pgt_cache() from within flush_tlb_mm(),
and i386 is already calling check_pgt_cache() from the usual places,
tlb_finish_mmu() and cpu_idle() (the latter being odd, but not unusual).
flush_tlb_mm() has no business to be freeing pages: remove that line, which
sneaked in with slub's i386 support.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Andi Kleen <ak@suse.de>
Acked-by: Christoph Lameter <clameter@sgi.com>
Acked-by: William Lee Irwin III <wli@holomorphy.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Several parts of kernel/smp.c and smpboot.c are generally useful for other
subarchitectures and paravirt_ops implementations, so make them available for
reuse.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SLUB cannot run on i386 at this point because i386 uses the page->private and
page->index field of slab pages for the pgd cache.
Make SLUB run on i386 by replacing the pgd slab cache with a quicklist.
Limit the changes as much as possible. Leave the improvised linked list in place
etc etc. This has been working here for a couple of weeks now.
Acked-by: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.
Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Avoid checking for cpu gone in mm hot path when CONFIG_HOTPLUG_CPU is not
defined.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
18 years ago
Fernando Luis [** ISO-8859-1 charset **] VzquezCao
Use safe_apic_wait_icr_idle to check ICR idle bit if the vector is
NMI_VECTOR to avoid potential hangups in the event of crash when kdump
tries to stop the other CPUs.
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Andi Kleen <ak@suse.de>
18 years ago
Fernando Luis [** ISO-8859-1 charset **] VzquezCao
Implement __send_IPI_dest_field which can be used to send IPIs when the
"destination shorthand" field of the ICR is set to 00 (destination
field). Use it whenever possible.
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Andi Kleen <ak@suse.de>
This patch adds a pv_op for flush_tlb_others. Linux running on native
hardware uses cross-CPU IPIs to flush the TLB on any CPU which may
have a particular mm's pagetable entries cached in its TLB. This is
inefficient in a paravirtualized environment, since the hypervisor
knows which real CPUs actually contain cached mappings, which may be a
small subset of a guest's VCPUs.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Update documentation for i386 smp_call_function* functions.
As reported by Randy Dunlap <rdunlap@xenotime.net>
[ I've posted this before but it seems to have been lost along the way. ]
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Add a smp_ops interface. This abstracts the API defined by
<linux/smp.h> for use within arch/i386. The primary intent is that it
be used by a paravirtualizing hypervisor to implement SMP, but it
could also be used by non-APIC-using sub-architectures.
This is related to CONFIG_PARAVIRT, but is implemented unconditionally
since it is simpler that way and not a highly performance-sensitive
interface.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
smp_call_function and smp_call_function_single are almost complete
duplicates of the same logic. This patch combines them by
implementing them in terms of the more general
smp_call_function_mask().
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Stephane Eranian <eranian@hpl.hp.com>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Andi Kleen <ak@suse.de>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Ingo Molnar <mingo@elte.hu>
Synchronize i386's smp_send_stop() with x86-64's in only try-locking
the call lock to prevent deadlocks when called from panic().
In both version, disable interrupts before clearing the CPU off the
online map to eliminate races with IRQ handlers inspecting this map.
Also in both versions, save/restore interrupts rather than disabling/
enabling them.
On x86-64, eliminate one function used here by folding it into its
single caller, convert to static, and rename for consistency with i386
(lkcd may like this).
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
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>
Add a notifier mechanism to the low level idle loop. You can register a
callback function which gets invoked on entry and exit from the low level idle
loop. The low level idle loop is defined as the polling loop, low-power call,
or the mwait instruction. Interrupts processed by the idle thread are not
considered part of the low level loop.
The notifier can be used to measure precisely how much is spent in useless
execution (or low power mode). The perfmon subsystem uses it to turn on/off
monitoring.
Signed-off-by: stephane eranian <eranian@hpl.hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Andi Kleen <ak@suse.de>
smp_call_function_single() can deadlock if the caller disabled local
interrupts (the target CPU could be spinning on call_lock). Check for that.
Why on earth do these functions use spin_lock_bh()??
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Andi Kleen <ak@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We don't need to setup _irq_regs in smp_xxx_interrupt (except apic timer).
These handlers run with irqs disabled and do not call functions which need
"struct pt_regs".
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@suse.de>
Acked-By: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
This is a the first of a series of patch-sets aiming at making kdump more
robust against stack overflows.
This patch set does the following:
* Add safe_smp_processor_id function to i386 architecture (this function was
inspired by the x86_64 function of the same name).
* Substitute "smp_processor_id" with the stack overflow-safe
"safe_smp_processor_id" in the reboot path to the second kernel.
This patch:
On the event of a stack overflow critical data that usually resides at the
bottom of the stack is likely to be stomped and, consequently, its use should
be avoided.
In particular, in the i386 and IA64 architectures the macro smp_processor_id
ultimately makes use of the "cpu" member of struct thread_info which resides
at the bottom of the stack. x86_64, on the other hand, is not affected by
this problem because it benefits from the use of the PDA infrastructure.
To circumvent this problem I suggest implementing "safe_smp_processor_id()"
(it already exists in x86_64) for i386 and IA64 and use it as a replacement
for smp_processor_id in the reboot path to the dump capture kernel. This is a
possible implementation for i386.
Signed-off-by: Fernando Vazquez <fernando@intellilink.co.jp>
Looks-reasonable-to: Andi Kleen <ak@muc.de>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If we're going to implement smp_call_function_single() on three architecture
with the same prototype then it should have a declaration in a
non-arch-specific header file.
Move it into <linux/smp.h>.
Cc: Stephane Eranian <eranian@hpl.hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Continiung the series of small patches necessary for the perfmon subsystem,
here is a patch that adds support for the smp_call_function_single()
function for i386. It exists for almost all other architectures but i386.
The perfmon subsystem needs it in one case to free some state on a
designated remote CPU.
Signed-off-by: Stephane Eranian <eranian@hpl.hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
x86_64 and i386 behave inconsistently when sending an IPI on vector 2
(NMI_VECTOR). Make both behave the same, so IPI 2 is sent as NMI.
The crash code was abusing send_IPI_allbutself() by passing a code
instead of a vector, it only worked because crash knew about the
internal code of send_IPI_allbutself(). Change crash to use NMI_VECTOR
instead, and remove the comment about how crash was abusing the function.
This patch is a pre-requisite for fixing the problem where sending an
IPI as NMI would reboot some Dell Xeon systems. I cannot fix that
problem while crash continus to abuse send_IPI_allbutself().
It also removes the inconsistency between i386 and x86_64 for
NMI_VECTOR. That will simplify all the RAS code that needs to bring
all the cpus to a clean stop, even when one or more cpus are spinning
disabled.
Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When on_each_cpu() runs the callback on other CPUs, it runs with local
interrupts disabled. So we should run the function with local interrupts
disabled on this CPU, too.
And do the same for UP, so the callback is run in the same environment on both
UP and SMP. (strictly it should do preempt_disable() too, but I think
local_irq_disable is sufficiently equivalent).
Also uninlines on_each_cpu(). softirq.c was the most appropriate file I could
find, but it doesn't seem to justify creating a new file.
Oh, and fix up that comment over (under?) x86's smp_call_function(). It
drives me nuts.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Most of these guys are simply not needed (pulled by other stuff
via asm-i386/hardirq.h). One that is not entirely useless is hilarious -
arch/i386/oprofile/nmi_timer_int.c includes linux/irq.h... as a way to
get linux/errno.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
i386 Inline asm cleanup. Use cr/dr accessor functions.
Also, a potential bugfix. Also, some CR accessors really should be volatile.
Reads from CR0 (numeric state may change in an exception handler), writes to
CR4 (flipping CR4.TSD) and reads from CR2 (page fault) prevent instruction
re-ordering. I did not add memory clobber to CR3 / CR4 / CR0 updates, as it
was not there to begin with, and in no case should kernel memory be clobbered,
except when doing a TLB flush, which already has memory clobber.
I noticed that page invalidation does not have a memory clobber. I can't find
a bug as a result, but there is definitely a potential for a bug here:
#define __flush_tlb_single(addr) \
__asm__ __volatile__("invlpg %0": :"m" (*(char *) addr))
Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make SEP init per-cpu, so it is hotplug safe.
Signed-off-by: Li Shaohua<shaohua.li@intel.com>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
(The i386 CPU hotplug patch provides infrastructure for some work which Pavel
is doing as well as for ACPI S3 (suspend-to-RAM) work which Li Shaohua
<shaohua.li@intel.com> is doing)
The following provides i386 architecture support for safely unregistering and
registering processors during runtime, updated for the current -mm tree. In
order to avoid dumping cpu hotplug code into kernel/irq/* i dropped the
cpu_online check in do_IRQ() by modifying fixup_irqs(). The difference being
that on cpu offline, fixup_irqs() is called before we clear the cpu from
cpu_online_map and a long delay in order to ensure that we never have any
queued external interrupts on the APICs. There are additional changes to s390
and ppc64 to account for this change.
1) Add CONFIG_HOTPLUG_CPU
2) disable local APIC timer on dead cpus.
3) Disable preempt around irq balancing to prevent CPUs going down.
4) Print irq stats for all possible cpus.
5) Debugging check for interrupts on offline cpus.
6) Hacky fixup_irqs() to redirect irqs when cpus go off/online.
7) play_dead() for offline cpus to spin inside.
8) Handle offline cpus set in flush_tlb_others().
9) Grab lock earlier in smp_call_function() to prevent CPUs going down.
10) Implement __cpu_disable() and __cpu_die().
11) Enable local interrupts in cpu_enable() after fixup_irqs()
12) Don't fiddle with NMI on dead cpu, but leave intact on other cpus.
13) Program IRQ affinity whilst cpu is still in cpu_online_map on offline.
Signed-off-by: Zwane Mwaikambo <zwane@linuxpower.ca>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* EXPORT_SYMBOL's moved to other files
* #include <linux/config.h>, <linux/module.h> where needed
* #include's in i386_ksyms.c cleaned up
* After copy-paste, redundant due to Makefiles rules preprocessor directives
removed:
#ifdef CONFIG_FOO
EXPORT_SYMBOL(foo);
#endif
obj-$(CONFIG_FOO) += foo.o
* Tiny reformat to fit in 80 columns
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Alex Nixon