Commit Graph

2932 Commits

Author SHA1 Message Date
Paul Mackerras 371fefd6f2 KVM: PPC: Allow book3s_hv guests to use SMT processor modes
This lifts the restriction that book3s_hv guests can only run one
hardware thread per core, and allows them to use up to 4 threads
per core on POWER7.  The host still has to run single-threaded.

This capability is advertised to qemu through a new KVM_CAP_PPC_SMT
capability.  The return value of the ioctl querying this capability
is the number of vcpus per virtual CPU core (vcore), currently 4.

To use this, the host kernel should be booted with all threads
active, and then all the secondary threads should be offlined.
This will put the secondary threads into nap mode.  KVM will then
wake them from nap mode and use them for running guest code (while
they are still offline).  To wake the secondary threads, we send
them an IPI using a new xics_wake_cpu() function, implemented in
arch/powerpc/sysdev/xics/icp-native.c.  In other words, at this stage
we assume that the platform has a XICS interrupt controller and
we are using icp-native.c to drive it.  Since the woken thread will
need to acknowledge and clear the IPI, we also export the base
physical address of the XICS registers using kvmppc_set_xics_phys()
for use in the low-level KVM book3s code.

When a vcpu is created, it is assigned to a virtual CPU core.
The vcore number is obtained by dividing the vcpu number by the
number of threads per core in the host.  This number is exported
to userspace via the KVM_CAP_PPC_SMT capability.  If qemu wishes
to run the guest in single-threaded mode, it should make all vcpu
numbers be multiples of the number of threads per core.

We distinguish three states of a vcpu: runnable (i.e., ready to execute
the guest), blocked (that is, idle), and busy in host.  We currently
implement a policy that the vcore can run only when all its threads
are runnable or blocked.  This way, if a vcpu needs to execute elsewhere
in the kernel or in qemu, it can do so without being starved of CPU
by the other vcpus.

When a vcore starts to run, it executes in the context of one of the
vcpu threads.  The other vcpu threads all go to sleep and stay asleep
until something happens requiring the vcpu thread to return to qemu,
or to wake up to run the vcore (this can happen when another vcpu
thread goes from busy in host state to blocked).

It can happen that a vcpu goes from blocked to runnable state (e.g.
because of an interrupt), and the vcore it belongs to is already
running.  In that case it can start to run immediately as long as
the none of the vcpus in the vcore have started to exit the guest.
We send the next free thread in the vcore an IPI to get it to start
to execute the guest.  It synchronizes with the other threads via
the vcore->entry_exit_count field to make sure that it doesn't go
into the guest if the other vcpus are exiting by the time that it
is ready to actually enter the guest.

Note that there is no fixed relationship between the hardware thread
number and the vcpu number.  Hardware threads are assigned to vcpus
as they become runnable, so we will always use the lower-numbered
hardware threads in preference to higher-numbered threads if not all
the vcpus in the vcore are runnable, regardless of which vcpus are
runnable.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:57 +03:00
Paul Mackerras a8606e20e4 KVM: PPC: Handle some PAPR hcalls in the kernel
This adds the infrastructure for handling PAPR hcalls in the kernel,
either early in the guest exit path while we are still in real mode,
or later once the MMU has been turned back on and we are in the full
kernel context.  The advantage of handling hcalls in real mode if
possible is that we avoid two partition switches -- and this will
become more important when we support SMT4 guests, since a partition
switch means we have to pull all of the threads in the core out of
the guest.  The disadvantage is that we can only access the kernel
linear mapping, not anything vmalloced or ioremapped, since the MMU
is off.

This also adds code to handle the following hcalls in real mode:

H_ENTER       Add an HPTE to the hashed page table
H_REMOVE      Remove an HPTE from the hashed page table
H_READ        Read HPTEs from the hashed page table
H_PROTECT     Change the protection bits in an HPTE
H_BULK_REMOVE Remove up to 4 HPTEs from the hashed page table
H_SET_DABR    Set the data address breakpoint register

Plus code to handle the following hcalls in the kernel:

H_CEDE        Idle the vcpu until an interrupt or H_PROD hcall arrives
H_PROD        Wake up a ceded vcpu
H_REGISTER_VPA Register a virtual processor area (VPA)

The code that runs in real mode has to be in the base kernel, not in
the module, if KVM is compiled as a module.  The real-mode code can
only access the kernel linear mapping, not vmalloc or ioremap space.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:55 +03:00
Paul Mackerras de56a948b9 KVM: PPC: Add support for Book3S processors in hypervisor mode
This adds support for KVM running on 64-bit Book 3S processors,
specifically POWER7, in hypervisor mode.  Using hypervisor mode means
that the guest can use the processor's supervisor mode.  That means
that the guest can execute privileged instructions and access privileged
registers itself without trapping to the host.  This gives excellent
performance, but does mean that KVM cannot emulate a processor
architecture other than the one that the hardware implements.

This code assumes that the guest is running paravirtualized using the
PAPR (Power Architecture Platform Requirements) interface, which is the
interface that IBM's PowerVM hypervisor uses.  That means that existing
Linux distributions that run on IBM pSeries machines will also run
under KVM without modification.  In order to communicate the PAPR
hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code
to include/linux/kvm.h.

Currently the choice between book3s_hv support and book3s_pr support
(i.e. the existing code, which runs the guest in user mode) has to be
made at kernel configuration time, so a given kernel binary can only
do one or the other.

This new book3s_hv code doesn't support MMIO emulation at present.
Since we are running paravirtualized guests, this isn't a serious
restriction.

With the guest running in supervisor mode, most exceptions go straight
to the guest.  We will never get data or instruction storage or segment
interrupts, alignment interrupts, decrementer interrupts, program
interrupts, single-step interrupts, etc., coming to the hypervisor from
the guest.  Therefore this introduces a new KVMTEST_NONHV macro for the
exception entry path so that we don't have to do the KVM test on entry
to those exception handlers.

We do however get hypervisor decrementer, hypervisor data storage,
hypervisor instruction storage, and hypervisor emulation assist
interrupts, so we have to handle those.

In hypervisor mode, real-mode accesses can access all of RAM, not just
a limited amount.  Therefore we put all the guest state in the vcpu.arch
and use the shadow_vcpu in the PACA only for temporary scratch space.
We allocate the vcpu with kzalloc rather than vzalloc, and we don't use
anything in the kvmppc_vcpu_book3s struct, so we don't allocate it.
We don't have a shared page with the guest, but we still need a
kvm_vcpu_arch_shared struct to store the values of various registers,
so we include one in the vcpu_arch struct.

The POWER7 processor has a restriction that all threads in a core have
to be in the same partition.  MMU-on kernel code counts as a partition
(partition 0), so we have to do a partition switch on every entry to and
exit from the guest.  At present we require the host and guest to run
in single-thread mode because of this hardware restriction.

This code allocates a hashed page table for the guest and initializes
it with HPTEs for the guest's Virtual Real Memory Area (VRMA).  We
require that the guest memory is allocated using 16MB huge pages, in
order to simplify the low-level memory management.  This also means that
we can get away without tracking paging activity in the host for now,
since huge pages can't be paged or swapped.

This also adds a few new exports needed by the book3s_hv code.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:54 +03:00
Paul Mackerras 3c42bf8a71 KVM: PPC: Split host-state fields out of kvmppc_book3s_shadow_vcpu
There are several fields in struct kvmppc_book3s_shadow_vcpu that
temporarily store bits of host state while a guest is running,
rather than anything relating to the particular guest or vcpu.
This splits them out into a new kvmppc_host_state structure and
modifies the definitions in asm-offsets.c to suit.

On 32-bit, we have a kvmppc_host_state structure inside the
kvmppc_book3s_shadow_vcpu since the assembly code needs to be able
to get to them both with one pointer.  On 64-bit they are separate
fields in the PACA.  This means that on 64-bit we don't need to
copy the kvmppc_host_state in and out on vcpu load/unload, and
in future will mean that the book3s_hv code doesn't need a
shadow_vcpu struct in the PACA at all.  That does mean that we
have to be careful not to rely on any values persisting in the
hstate field of the paca across any point where we could block
or get preempted.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:53 +03:00
Paul Mackerras 923c53caea powerpc: Set up LPCR for running guest partitions
In hypervisor mode, the LPCR controls several aspects of guest
partitions, including virtual partition memory mode, and also controls
whether the hypervisor decrementer interrupts are enabled.  This sets
up LPCR at boot time so that guest partitions will use a virtual real
memory area (VRMA) composed of 16MB large pages, and hypervisor
decrementer interrupts are disabled.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:52 +03:00
Paul Mackerras b01c8b54a1 powerpc, KVM: Rework KVM checks in first-level interrupt handlers
Instead of branching out-of-line with the DO_KVM macro to check if we
are in a KVM guest at the time of an interrupt, this moves the KVM
check inline in the first-level interrupt handlers.  This speeds up
the non-KVM case and makes sure that none of the interrupt handlers
are missing the check.

Because the first-level interrupt handlers are now larger, some things
had to be move out of line in exceptions-64s.S.

This all necessitated some minor changes to the interrupt entry code
in KVM.  This also streamlines the book3s_32 KVM test.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:48 +03:00
Liu Yu dd9ebf1f94 KVM: PPC: e500: Add shadow PID support
Dynamically assign host PIDs to guest PIDs, splitting each guest PID into
multiple host (shadow) PIDs based on kernel/user and MSR[IS/DS].  Use
both PID0 and PID1 so that the shadow PIDs for the right mode can be
selected, that correspond both to guest TID = zero and guest TID = guest
PID.

This allows us to significantly reduce the frequency of needing to
invalidate the entire TLB.  When the guest mode or PID changes, we just
update the host PID0/PID1.  And since the allocation of shadow PIDs is
global, multiple guests can share the TLB without conflict.

Note that KVM does not yet support the guest setting PID1 or PID2 to
a value other than zero.  This will need to be fixed for nested KVM
to work.  Until then, we enforce the requirement for guest PID1/PID2
to stay zero by failing the emulation if the guest tries to set them
to something else.

Signed-off-by: Liu Yu <yu.liu@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:39 +03:00
Scott Wood 4cd35f675b KVM: PPC: e500: Save/restore SPE state
This is done lazily.  The SPE save will be done only if the guest has
used SPE since the last preemption or heavyweight exit.  Restore will be
done only on demand, when enabling MSR_SPE in the shadow MSR, in response
to an SPE fault or mtmsr emulation.

For SPEFSCR, Linux already switches it on context switch (non-lazily), so
the only remaining bit is to save it between qemu and the guest.

Signed-off-by: Liu Yu <yu.liu@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:32 +03:00
Scott Wood ecee273fc4 KVM: PPC: booke: use shadow_msr
Keep the guest MSR and the guest-mode true MSR separate, rather than
modifying the guest MSR on each guest entry to produce a true MSR.

Any bits which should be modified based on guest MSR must be explicitly
propagated from vcpu->arch.shared->msr to vcpu->arch.shadow_msr in
kvmppc_set_msr().

While we're modifying the guest entry code, reorder a few instructions
to bury some load latencies.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:32 +03:00
Scott Wood c51584d52e powerpc/e500: SPE register saving: take arbitrary struct offset
Previously, these macros hardcoded THREAD_EVR0 as the base of the save
area, relative to the base register passed.  This base offset is now
passed as a separate macro parameter, allowing reuse with other SPE
save areas, such as used by KVM.

Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:31 +03:00
yu liu 685659ee70 powerpc/e500: Save SPEFCSR in flush_spe_to_thread()
giveup_spe() saves the SPE state which is protected by MSR[SPE].
However, modifying SPEFSCR does not trap when MSR[SPE]=0.
And since SPEFSCR is already saved/restored in _switch(),
not all the callers want to save SPEFSCR again.
Thus, saving SPEFSCR should not belong to giveup_spe().

This patch moves SPEFSCR saving to flush_spe_to_thread(),
and cleans up the caller that needs to save SPEFSCR accordingly.

Signed-off-by: Liu Yu <yu.liu@freescale.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:30 +03:00
Christian Dietrich 76462232c2 arch/powerpc: use printk_ratelimited instead of printk_ratelimit
Since printk_ratelimit() shouldn't be used anymore (see comment in
include/linux/printk.h), replace it with printk_ratelimited.

Signed-off-by: Christian Dietrich <christian.dietrich@informatik.uni-erlangen.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-29 15:31:01 +10:00
Christian Dietrich 9a8f99fab0 powerpc/rtas-rtc: remove sideeffects of printk_ratelimit
Don't use printk_ratelimit() as an additional condition for returning
on an error. Because when the ratelimit is reached, printk_ratelimit
will return 0 and e.g. in rtas_get_boot_time won't check for an error
condition.

Signed-off-by: Christian Dietrich <christian.dietrich@informatik.uni-erlangen.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-29 15:30:43 +10:00
Scott Wood 82a9a4809f powerpc/e500: fix breakage with fsl_rio_mcheck_exception
The wrong MCSR bit was being used on e500mc.  MCSR_BUS_RBERR only exists
on e500v1/v2.  Use MCSR_LD on e500mc, and remove all MCSR checking
in fsl_rio_mcheck_exception as we now no longer call that function
if the appropriate bit in MCSR is not set.

If RIO support was enabled at compile-time, but was never probed, just
return from fsl_rio_mcheck_exception rather than dereference a NULL
pointer.

TODO: There is still a remaining, though comparitively minor, issue in
that this recovery mechanism will falsely engage if there's an unrelated
MCSR_LD event at the same time as a RIO error.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-06-22 06:15:16 -05:00
Benjamin Herrenschmidt 307cfe7153 powerpc: Force page alignment for initrd reserved memory
When using 64K pages with a separate cpio rootfs, U-Boot will align
the rootfs on a 4K page boundary. When the memory is reserved, and
subsequent early memblock_alloc is called, it will allocate memory
between the 64K page alignment and reserved memory. When the reserved
memory is subsequently freed, it is done so by pages, causing the
early memblock_alloc requests to be re-used, which in my case, caused
the device-tree to be clobbered.

This patch forces the reserved memory for initrd to be kernel page
aligned, and will move the device tree if it overlaps with the range
extension of initrd. This patch will also consolidate the identical
function free_initrd_mem() from mm/init_32.c, init_64.c to mm/mem.c,
and adds the same range extension when freeing initrd. free_initrd_mem()
is also moved to the __init section.

Many thanks to Milton Miller for his input on this patch.

[BenH: Fixed build without CONFIG_BLK_DEV_INITRD]

Signed-off-by: Dave Carroll <dcarroll@astekcorp.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-09 16:52:38 +10:00
Benjamin Herrenschmidt d660474e84 Merge remote branch 'kumar/merge' into merge 2011-06-09 14:46:32 +10:00
Kumar Gala fb9be2349f powerpc/book3e: Fix CPU feature handling on e5500 in 32-bit mode
We are missing FPU feature bit that user space may require.  In the
64-bit mode this gets set since we pull it in via COMMON_USER_PPC64.  We
just explicitly set it so user space will be happy again.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-06-02 15:29:09 -05:00
Linus Torvalds 2a56d22202 Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (45 commits)
  ARM: 6945/1: Add unwinding support for division functions
  ARM: kill pmd_off()
  ARM: 6944/1: mm: allow ASID 0 to be allocated to tasks
  ARM: 6943/1: mm: use TTBR1 instead of reserved context ID
  ARM: 6942/1: mm: make TTBR1 always point to swapper_pg_dir on ARMv6/7
  ARM: 6941/1: cache: ensure MVA is cacheline aligned in flush_kern_dcache_area
  ARM: add sendmmsg syscall
  ARM: 6863/1: allow hotplug on msm
  ARM: 6832/1: mmci: support for ST-Ericsson db8500v2
  ARM: 6830/1: mach-ux500: force PrimeCell revisions
  ARM: 6829/1: amba: make hardcoded periphid override hardware
  ARM: 6828/1: mach-ux500: delete SSP PrimeCell ID
  ARM: 6827/1: mach-netx: delete hardcoded periphid
  ARM: 6940/1: fiq: Briefly document driver responsibilities for suspend/resume
  ARM: 6938/1: fiq: Refactor {get,set}_fiq_regs() for Thumb-2
  ARM: 6914/1: sparsemem: fix highmem detection when using SPARSEMEM
  ARM: 6913/1: sparsemem: allow pfn_valid to be overridden when using SPARSEMEM
  at91: drop at572d940hf support
  at91rm9200: introduce at91rm9200_set_type to specficy cpu package
  at91: drop boot_params and PLAT_PHYS_OFFSET
  ...
2011-05-27 19:51:32 -07:00
Russell King 239df0fd5e Merge branches 'devel', 'devel-stable' and 'fixes' into for-linus 2011-05-27 22:59:57 +01:00
Linus Torvalds f23a5e1405 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
  PM: Fix PM QOS's user mode interface to work with ASCII input
  PM / Hibernate: Update kerneldoc comments in hibernate.c
  PM / Hibernate: Remove arch_prepare_suspend()
  PM / Hibernate: Update some comments in core hibernate code
2011-05-27 14:27:34 -07:00
Benjamin Herrenschmidt 9693ebd481 Merge remote branch 'kumar/merge' into merge 2011-05-27 09:58:22 +10:00
Milton Miller 4dd6029001 powerpc: Fix irq_free_virt by adjusting bounds before loop
Instead of looping over each irq and checking against the irq array
bounds, adjust the bounds before looping.

The old code will not free any irq if the irq + count is above
irq_virq_count because the test in the loop is testing irq + count
instead of irq + i.

This code checks the limits to avoid unsigned integer overflows.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26 13:38:59 +10:00
Milton Miller 9b78825158 powerpc/irq: Protect irq_radix_revmap_lookup against irq_free_virt
The radix-tree code uses call_rcu when freeing internal elements.
We must protect against the elements being freed while we traverse
the tree, even if the returned pointer will still be valid.

While preparing a patch to expand the context in which
irq_radix_revmap_lookup will be called, I realized that the
radix tree was not locked.

When asked

    For a normal call_rcu usage, is it allowed to read the structure in
    irq_enter / irq_exit, without additional rcu_read_lock?  Could an
    element freed with call_rcu advance with the cpu still between
    irq_enter/irq_exit (and irq_disabled())?

Paul McKenney replied:

    Absolutely illegal to do so. OK for call_rcu_sched(), but a
    flaming bug for call_rcu().

    And thank you very much for finding this!!!

Further analysis:

In the current CONFIG_TREE_RCU implementation. CONFIG_TREE_PREEMPT_RCU
(and CONFIG_TINY_PREEMPT_RCU) uses explicit counters.

These counters are reflected from per-CPU to global in the
scheduling-clock-interrupt handler, so disabling irq does prevent the
grace period from completing. But there are real-time implementations
(such as the one use by the Concurrent guys) where disabling irq
does -not- prevent the grace period from completing.

While an alternative fix would be to switch radix-tree to rcu_sched, I
don't want to audit the other users of radix trees (nor put alternative
freeing in the library).  The normal overhead for rcu_read_lock and
unlock are a local counter increment and decrement.

This does not show up in the rcu lockdep because in 2.6.34 commit
2676a58c98 (radix-tree: Disable RCU lockdep checking in radix tree)
deemed it too hard to pass the condition of the protecting lock
to the library.

Signed-off-by: Milton Miller <miltonm@bga.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26 13:38:59 +10:00
Milton Miller 2e455257d1 powerpc/irq: Check desc in handle_one_irq and expand generic_handle_irq
Look up the descriptor and check that it is found in handle_one_irq
before checking if we are on the irq stack, and call the handler
directly using the descriptor if we are on the stack.

We need check irq_to_desc finds the descriptor to avoid a NULL
pointer dereference.  It could have failed because the number from
ppc_md.get_irq was above NR_IRQS, or various exceptional conditions
with sparse irqs (eg race conditions while freeing an irq if its was
not shutdown in the controller).

fe12bc2c99 (genirq: Uninline and sanity check generic_handle_irq())
moved generic_handle_irq out of line to allow its use by interrupt
controllers in modules.  However, handle_one_irq is core arch code.
It already knows the details of struct irq_desc and handling irqs in
the nested irq case.  This will avoid the extra stack frame to return
the value we don't check.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26 13:38:59 +10:00
Milton Miller 3d1b5e206a powerpc/irq: Always free duplicate IRQ_LEGACY hosts
Since kmem caches are allocated before init_IRQ as noted in 3af259d155
(powerpc: Radix trees are available before init_IRQ), we now call
kmalloc in all cases and can can always call kfree if we are asked
to allocate a duplicate or conflicting IRQ_HOST_MAP_LEGACY host.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26 13:38:59 +10:00
Milton Miller 8142f032a9 powerpc/irq: Remove stale and misleading comment
The comment claims we will call host->ops->map() to update the flags if
we find a previously established mapping, but we never did.  We used
to call remap, but that call was removed in da05198002 (powerpc: Remove
irq_host_ops->remap hook).

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26 13:38:58 +10:00
Milton Miller 7ef71d753e powerpc/cell: Use common smp ipi actions
The cell iic interrupt controller has enough software caused interrupts
to use a unique interrupt for each of the 4 messages powerpc uses.
This means each interrupt gets its own irq action/data combination.

Use the seperate, optimized, arch common ipi action functions
registered via the helper smp_request_message_ipi instead passing the
message as action data to a single action that then demultipexes to
the required acton via a switch statement.

smp_request_message_ipi will register the action as IRQF_PER_CPU
and IRQF_DISABLED, and WARN if the allocation fails for some reason,
so no need to print on that failure.  It will return positive if
the message will not be used by the kernel, in which case we can
free the virq.

In addition to elimiating inefficient code, this also corrects the
error that a kernel built with kexec but without a debugger would
not register the ipi for kdump to notify the other cpus of a crash.

This also restores the debugger action to be static to kernel/smp.c.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26 13:38:58 +10:00
Ian Munsie 02424d8966 powerpc/ftrace: Implement raw syscall tracepoints on PowerPC
This patch implements the raw syscall tracepoints on PowerPC and exports
them for ftrace syscalls to use.

To minimise reworking existing code, I slightly re-ordered the thread
info flags such that the new TIF_SYSCALL_TRACEPOINT bit would still fit
within the 16 bits of the andi. instruction's UI field. The instructions
in question are in /arch/powerpc/kernel/entry_{32,64}.S to and the
_TIF_SYSCALL_T_OR_A with the thread flags to see if system call tracing
is enabled.

In the case of 64bit PowerPC, arch_syscall_addr and
arch_syscall_match_sym_name are overridden to allow ftrace syscalls to
work given the unusual system call table structure and symbol names that
start with a period.

Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-26 13:38:57 +10:00
Russell King ae1d3b974e Merge branch 'for-rmk' of git://github.com/at91linux/linux-2.6-at91 into devel-stable 2011-05-26 00:41:21 +01:00
Peter Zijlstra d6bf29b44d powerpc: mmu_gather rework
Fix up powerpc to the new mmu_gather stuff.

PPC has an extra batching queue to RCU free the actual pagetable
allocations, use the ARCH extentions for that for now.

For the ppc64_tlb_batch, which tracks the vaddrs to unhash from the
hardware hash-table, keep using per-cpu arrays but flush on context switch
and use a TLF bit to track the lazy_mmu state.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Tony Luck <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:13 -07:00
Russell King 03eb14199e Merge branch 'devicetree/arm-next' of git://git.secretlab.ca/git/linux-2.6 into devel-stable 2011-05-25 00:08:17 +01:00
Rafael J. Wysocki 354258011e PM / Hibernate: Remove arch_prepare_suspend()
All architectures supporting hibernation define
arch_prepare_suspend() as an empty function, so remove it.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-05-24 23:35:55 +02:00
Linus Torvalds 5129df03d0 Merge branch 'for-2.6.40' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-2.6.40' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: Unify input section names
  percpu: Avoid extra NOP in percpu_cmpxchg16b_double
  percpu: Cast away printk format warning
  percpu: Always align percpu output section to PAGE_SIZE

Fix up fairly trivial conflict in arch/x86/include/asm/percpu.h as per Tejun
2011-05-24 11:53:42 -07:00
Linus Torvalds 57d19e80f4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits)
  b43: fix comment typo reqest -> request
  Haavard Skinnemoen has left Atmel
  cris: typo in mach-fs Makefile
  Kconfig: fix copy/paste-ism for dell-wmi-aio driver
  doc: timers-howto: fix a typo ("unsgined")
  perf: Only include annotate.h once in tools/perf/util/ui/browsers/annotate.c
  md, raid5: Fix spelling error in comment ('Ofcourse' --> 'Of course').
  treewide: fix a few typos in comments
  regulator: change debug statement be consistent with the style of the rest
  Revert "arm: mach-u300/gpio: Fix mem_region resource size miscalculations"
  audit: acquire creds selectively to reduce atomic op overhead
  rtlwifi: don't touch with treewide double semicolon removal
  treewide: cleanup continuations and remove logging message whitespace
  ath9k_hw: don't touch with treewide double semicolon removal
  include/linux/leds-regulator.h: fix syntax in example code
  tty: fix typo in descripton of tty_termios_encode_baud_rate
  xtensa: remove obsolete BKL kernel option from defconfig
  m68k: fix comment typo 'occcured'
  arch:Kconfig.locks Remove unused config option.
  treewide: remove extra semicolons
  ...
2011-05-23 09:12:26 -07:00
Linus Torvalds f4b10bc60a Merge branch 'kvm-updates/2.6.40' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.40' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (131 commits)
  KVM: MMU: Use ptep_user for cmpxchg_gpte()
  KVM: Fix kvm mmu_notifier initialization order
  KVM: Add documentation for KVM_CAP_NR_VCPUS
  KVM: make guest mode entry to be rcu quiescent state
  KVM: x86 emulator: Make jmp far emulation into a separate function
  KVM: x86 emulator: Rename emulate_grpX() to em_grpX()
  KVM: x86 emulator: Remove unused arg from emulate_pop()
  KVM: x86 emulator: Remove unused arg from writeback()
  KVM: x86 emulator: Remove unused arg from read_descriptor()
  KVM: x86 emulator: Remove unused arg from seg_override()
  KVM: Validate userspace_addr of memslot when registered
  KVM: MMU: Clean up gpte reading with copy_from_user()
  KVM: PPC: booke: add sregs support
  KVM: PPC: booke: save/restore VRSAVE (a.k.a. USPRG0)
  KVM: PPC: use ticks, not usecs, for exit timing
  KVM: PPC: fix exit accounting for SPRs, tlbwe, tlbsx
  KVM: PPC: e500: emulate SVR
  KVM: VMX: Cache vmcs segment fields
  KVM: x86 emulator: consolidate segment accessors
  KVM: VMX: Avoid reading %rip unnecessarily when handling exceptions
  ...
2011-05-23 08:42:08 -07:00
Scott Wood eab176722f KVM: PPC: booke: save/restore VRSAVE (a.k.a. USPRG0)
Linux doesn't use USPRG0 (now renamed VRSAVE in the architecture, even
when Altivec isn't involved), but a guest might.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-05-22 08:47:50 -04:00
Josh Boyer 6de06f313a powerpc: Fix 32-bit SMP build
Commit 69e3cea8d5 ("powerpc/smp: Make start_secondary_resume
available to all CPU variants") introduced start_secondary_resume to
misc_32.S, however it uses a 64-bit instruction which is not valid on
32-bit platforms.  Use 'stw' instead.

Reported-by: Richard Cochran <richardcochran@gmail.com>
Tested-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-20 16:23:19 -07:00
Shaohui Xie cce1f106c6 powerpc/fsl_rio: move machine_check handler
Add support for machine_check support into machine_check_e500 and
machine_check_e500mc.

Signed-off-by: Shaohui Xie <b21989@freescale.com>
Cc: Li Yang <leoli@freescale.com>
Cc: Roy Zang <tie-fei.zang@freescale.com>
Cc: Alexandre Bounine <alexandre.bounine@idt.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-05-20 08:46:57 -05:00
Benjamin Herrenschmidt 208b3a4c19 powerpc: Fix hard CPU IDs detection
commit 9d07bc841c
"powerpc: Properly handshake CPUs going out of boot spin loop"

Would cause a miscalculation of the hard CPU ID. It removes breaking
out of the loop when finding a match with a processor, thus the "i"
used as an index in the intserv array is always incorrect

This broke interrupt on my PowerMac laptop.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-20 17:50:18 +10:00
Benjamin Herrenschmidt 880102e785 Merge remote branch 'origin/master' into merge
Manual merge of arch/powerpc/kernel/smp.c and add missing scheduler_ipi()
call to arch/powerpc/platforms/cell/interrupt.c

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-20 15:36:52 +10:00
Benjamin Herrenschmidt 3d07f0e83d Merge remote branch 'kumar/next' into next 2011-05-20 13:43:47 +10:00
Linus Torvalds 39ab05c8e0 Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (44 commits)
  debugfs: Silence DEBUG_STRICT_USER_COPY_CHECKS=y warning
  sysfs: remove "last sysfs file:" line from the oops messages
  drivers/base/memory.c: fix warning due to "memory hotplug: Speed up add/remove when blocks are larger than PAGES_PER_SECTION"
  memory hotplug: Speed up add/remove when blocks are larger than PAGES_PER_SECTION
  SYSFS: Fix erroneous comments for sysfs_update_group().
  driver core: remove the driver-model structures from the documentation
  driver core: Add the device driver-model structures to kerneldoc
  Translated Documentation/email-clients.txt
  RAW driver: Remove call to kobject_put().
  reboot: disable usermodehelper to prevent fs access
  efivars: prevent oops on unload when efi is not enabled
  Allow setting of number of raw devices as a module parameter
  Introduce CONFIG_GOOGLE_FIRMWARE
  driver: Google Memory Console
  driver: Google EFI SMI
  x86: Better comments for get_bios_ebda()
  x86: get_bios_ebda_length()
  misc: fix ti-st build issues
  params.c: Use new strtobool function to process boolean inputs
  debugfs: move to new strtobool
  ...

Fix up trivial conflicts in fs/debugfs/file.c due to the same patch
being applied twice, and an unrelated cleanup nearby.
2011-05-19 18:24:11 -07:00
Sebastian Siewior f38aa70877 powerpc: Remove last piece of GEMINI
It seems that Adrian is getting old. He removed almost everything of
GEMINI in commit c53653130 ("[POWERPC] Remove the broken Gemini
support") except this piece.

Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-19 17:32:29 +10:00
Gabriel Paubert 2c78027a62 powerpc: Fix for Pegasos keyboard and mouse
[See http://lists.ozlabs.org/pipermail/linuxppc-dev/2010-October/086424.html
and followups. Part of the commit message is directly copied from that.]

Commit 540c6c392f tries to find i8042 IRQs in
the device-tree but doesn't fall back to the old hardcoded 1 and 12 in all
failure cases.

Specifically, the case where the device-tree contains nothing matching
pnpPNP,303 or pnpPNP,f03 doesn't seem to be handled well. It sort of falls
through to the old code, but leaves the IRQs set to 0.

Signed-off-by: Gabriel Paubert <paubert@iram.es>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-19 17:32:27 +10:00
Benjamin Herrenschmidt 03bf469add powerpc: Make early memory scan more resilient to out of order nodes
We keep track of the size of the lowest block of memory and call
setup_initial_memory_limit() only after we've parsed them all

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Milton Miller <miltonm@bga.com>
2011-05-19 17:32:25 +10:00
Benjamin Herrenschmidt 4c8440666b Merge branch 'merge' into next 2011-05-19 17:00:06 +10:00
Milton Miller 41fb5e6260 powerpc: Make IRQ_NOREQUEST last to clear, first to set
When creating an irq, don't allow a concurent driver request until
we have caled map, which will likley call set_chip_and_handler to
change the irq_chip and its operations.

Similarly, when tearing down an IRQ, make sure no new uses come
along while we change the irq back to the nop chip and then reset
the descriptor to freed status.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-05-19 16:54:46 +10:00
Scott Wood 3a6e9bd7f6 powerpc/e5500: set non-base IVORs
Without this, we attempt to use doorbells for IPIs, and end up
branching to some bad address.  Plus, even for the exceptions
we don't implement, it's good to handle it and get a message out.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-05-19 00:36:43 -05:00
Kumar Gala d36b4c4f3c powerpc/fsl-booke64: Add support for Debug Level exception handler
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-05-19 00:36:42 -05:00
Kumar Gala 134c428e5a Merge remote branch 'benh/merge' into benh-next 2011-05-19 00:36:21 -05:00