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Commit Graph

88 Commits

Author SHA1 Message Date
Alexander Graf
f7adbba1e5 KVM: PPC: Keep SRR1 flags around in shadow_msr
SRR1 stores more information that just the MSR value. It also stores
valuable information about the type of interrupt we received, for
example whether the storage interrupt we just got was because of a
missing htab entry or not.

We use that information to speed up the exit path.

Now if we get preempted before we can interpret the shadow_msr values,
we get into vcpu_put which then calls the MSR handler, which then sets
all the SRR1 information bits in shadow_msr to 0. Great.

So let's preserve the SRR1 specific bits in shadow_msr whenever we set
the MSR. They don't hurt.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:56 -03:00
Alexander Graf
021ec9c69f KVM: PPC: Call SLB patching code in interrupt safe manner
Currently we're racy when doing the transition from IR=1 to IR=0, from
the module memory entry code to the real mode SLB switching code.

To work around that I took a look at the RTAS entry code which is faced
with a similar problem and did the same thing:

  A small helper in linear mapped memory that does mtmsr with IR=0 and
  then RFIs info the actual handler.

Thanks to that trick we can safely take page faults in the entry code
and only need to be really wary of what to do as of the SLB switching
part.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:49 -03:00
Alexander Graf
7e57cba060 KVM: PPC: Use PACA backed shadow vcpu
We're being horribly racy right now. All the entry and exit code hijacks
random fields from the PACA that could easily be used by different code in
case we get interrupted, for example by a #MC or even page fault.

After discussing this with Ben, we figured it's best to reserve some more
space in the PACA and just shove off some vcpu state to there.

That way we can drastically improve the readability of the code, make it
less racy and less complex.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:48 -03:00
Kumar Gala
8b27f0b61d powerpc/fsl-booke: Rework TLB CAM code
Re-write the code so its more standalone and fixed some issues:
* Bump'd # of CAM entries to 64 to support e500mc
* Make the code handle MAS7 properly
* Use pr_cont instead of creating a string as we go

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2009-11-20 16:45:33 -06:00
Alexander Graf
55c758840a Export new PACA constants in asm-offsets
In order to access fields in the PACA from assembly code, we need
to generate offsets using asm-offsets.c.

So let's add the new PACA related bits, we just introduced!

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-11-05 16:50:26 +11:00
Alexander Graf
62908905b2 Add Book3s_64 offsets to asm-offsets.c
We need to access some VCPU fields from assembly code. In order to get
the proper offsets, we have to define them in asm-offsets.c.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-11-05 16:49:57 +11:00
Ingo Molnar
cdd6c482c9 perf: Do the big rename: Performance Counters -> Performance Events
Bye-bye Performance Counters, welcome Performance Events!

In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.

Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.

All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)

The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.

Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.

User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)

This patch has been generated via the following script:

  FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')

  sed -i \
    -e 's/PERF_EVENT_/PERF_RECORD_/g' \
    -e 's/PERF_COUNTER/PERF_EVENT/g' \
    -e 's/perf_counter/perf_event/g' \
    -e 's/nb_counters/nb_events/g' \
    -e 's/swcounter/swevent/g' \
    -e 's/tpcounter_event/tp_event/g' \
    $FILES

  for N in $(find . -name perf_counter.[ch]); do
    M=$(echo $N | sed 's/perf_counter/perf_event/g')
    mv $N $M
  done

  FILES=$(find . -name perf_event.*)

  sed -i \
    -e 's/COUNTER_MASK/REG_MASK/g' \
    -e 's/COUNTER/EVENT/g' \
    -e 's/\<event\>/event_id/g' \
    -e 's/counter/event/g' \
    -e 's/Counter/Event/g' \
    $FILES

... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.

Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.

( NOTE: 'counters' are still the proper terminology when we deal
  with hardware registers - and these sed scripts are a bit
  over-eager in renaming them. I've undone some of that, but
  in case there's something left where 'counter' would be
  better than 'event' we can undo that on an individual basis
  instead of touching an otherwise nicely automated patch. )

Suggested-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-21 14:28:04 +02:00
Benjamin Herrenschmidt
4f0dbc2781 Merge commit 'paulus-perf/master' into next 2009-08-20 11:07:56 +10:00
Benjamin Herrenschmidt
dce6670aaa powerpc: Add PACA fields specific to 64-bit Book3E processors
This adds various fields in the PACA that are for use specifically
by Book3E processors, such as exception save areas, current pgd
pointer, special exceptions kernel stacks etc...

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:25:08 +10:00
Benjamin Herrenschmidt
57e2a99f74 powerpc: Add memory management headers for new 64-bit BookE
This adds the PTE and pgtable format definitions, along with changes
to the kernel memory map and other definitions related to implementing
support for 64-bit Book3E. This also shields some asm-offset bits that
are currently only relevant on 32-bit

We also move the definition of the "linux" page size constants to
the common mmu.h file and add a few sizes that are relevant to
embedded processors.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:25:06 +10:00
Paul Mackerras
9c1e105238 powerpc: Allow perf_counters to access user memory at interrupt time
This provides a mechanism to allow the perf_counters code to access
user memory in a PMU interrupt routine.  Such an access can cause
various kinds of interrupt: SLB miss, MMU hash table miss, segment
table miss, or TLB miss, depending on the processor.  This commit
only deals with 64-bit classic/server processors, which use an MMU
hash table.  32-bit processors are already able to access user memory
at interrupt time.  Since we don't soft-disable on 32-bit, we avoid
the possibility of reentering hash_page or the TLB miss handlers,
since they run with interrupts disabled.

On 64-bit processors, an SLB miss interrupt on a user address will
update the slb_cache and slb_cache_ptr fields in the paca.  This is
OK except in the case where a PMU interrupt occurs in switch_slb,
which also accesses those fields.  To prevent this, we hard-disable
interrupts in switch_slb.  Interrupts are already soft-disabled at
this point, and will get hard-enabled when they get soft-enabled
later.

This also reworks slb_flush_and_rebolt: to avoid hard-disabling twice,
and to make sure that it clears the slb_cache_ptr when called from
other callers than switch_slb, the existing routine is renamed to
__slb_flush_and_rebolt, which is called by switch_slb and the new
version of slb_flush_and_rebolt.

Similarly, switch_stab (used on POWER3 and RS64 processors) gets a
hard_irq_disable() to protect the per-cpu variables used there and
in ste_allocate.

If a MMU hashtable miss interrupt occurs, normally we would call
hash_page to look up the Linux PTE for the address and create a HPTE.
However, hash_page is fairly complex and takes some locks, so to
avoid the possibility of deadlock, we check the preemption count
to see if we are in a (pseudo-)NMI handler, and if so, we don't call
hash_page but instead treat it like a bad access that will get
reported up through the exception table mechanism.  An interrupt
whose handler runs even though the interrupt occurred when
soft-disabled (such as the PMU interrupt) is considered a pseudo-NMI
handler, which should use nmi_enter()/nmi_exit() rather than
irq_enter()/irq_exit().

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-08-18 14:48:43 +10:00
Benjamin Herrenschmidt
bc47ab0241 Merge commit 'origin/master' into next
Manual merge of:
	arch/powerpc/kernel/asm-offsets.c
2009-06-12 16:53:38 +10:00
Benjamin Herrenschmidt
91c60b5b82 powerpc: Separate PACA fields for server CPUs
This patch has no effect other than re-ordering PACA fields on
current server CPUs. It however is a pre-requisite for future
support of BookE 64-bit processors. Various parts of the PACA
struct are now moved under some ifdef's, either the new
CONFIG_PPC_BOOK3S or CONFIG_PPC_STD_MMU_64, whatever seems more
appropriate.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.craashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-06-09 16:47:38 +10:00
Ingo Molnar
f541ae326f Merge branch 'linus' into perfcounters/core-v2
Merge reason: we have gathered quite a few conflicts, need to merge upstream

Conflicts:
	arch/powerpc/kernel/Makefile
	arch/x86/ia32/ia32entry.S
	arch/x86/include/asm/hardirq.h
	arch/x86/include/asm/unistd_32.h
	arch/x86/include/asm/unistd_64.h
	arch/x86/kernel/cpu/common.c
	arch/x86/kernel/irq.c
	arch/x86/kernel/syscall_table_32.S
	arch/x86/mm/iomap_32.c
	include/linux/sched.h
	kernel/Makefile

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-06 09:02:57 +02:00
Benjamin Herrenschmidt
9ff9a26b78 Merge commit 'origin/master' into next
Manual merge of:
	arch/powerpc/include/asm/elf.h
	drivers/i2c/busses/i2c-mpc.c
2009-03-30 14:04:53 +11:00
Hollis Blanchard
366d4b9b9f KVM: ppc: No need to include core-header for KVM in asm-offsets.c currently
Signed-off-by: Liu Yu <yu.liu@freescale.com>
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:58 +02:00
Michael Ellerman
9e1e3723be powerpc: Remove unused asm-offsets entries for cpu_spec
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-03-11 17:10:15 +11:00
Ingo Molnar
77835492ed Merge commit 'v2.6.29-rc2' into perfcounters/core
Conflicts:
	include/linux/syscalls.h
2009-01-21 16:37:27 +01:00
Benjamin Herrenschmidt
30aae739a9 Merge commit 'kumar/kumar-next' into next 2009-01-13 13:59:03 +11:00
Ingo Molnar
c0d362a832 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/perfcounters into perfcounters/core 2009-01-11 02:44:08 +01:00
Paul Mackerras
93a6d3ce69 powerpc: Provide a way to defer perf counter work until interrupts are enabled
Because 64-bit powerpc uses lazy (soft) interrupt disabling, it is
possible for a performance monitor exception to come in when the
kernel thinks interrupts are disabled (i.e. when they are
soft-disabled but hard-enabled).  In such a situation the performance
monitor exception handler might have some processing to do (such as
process wakeups) which can't be done in what is effectively an NMI
handler.

This provides a way to defer that work until interrupts get enabled,
either in raw_local_irq_restore() or by returning from an interrupt
handler to code that had interrupts enabled.  We have a per-processor
flag that indicates that there is work pending to do when interrupts
subsequently get re-enabled.  This flag is checked in the interrupt
return path and in raw_local_irq_restore(), and if it is set,
perf_counter_do_pending() is called to do the pending work.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-01-09 19:48:17 +11:00
Trent Piepho
19f5465e82 powerpc/fsl-booke: Don't hard-code size of struct tlbcam
Some assembly code in head_fsl_booke.S hard-coded the size of struct tlbcam
to 20 when it indexed the TLBCAM table.  Anyone changing the size of struct
tlbcam would not know to expect that.

The kernel already has a system to get the size of C structures into
assembly language files, asm-offsets, so let's use it.

The definition of the struct gets moved to a header, so that asm-offsets.c
can include it.

Signed-off-by: Trent Piepho <tpiepho@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2009-01-07 15:33:06 -06:00
Hollis Blanchard
73e75b416f KVM: ppc: Implement in-kernel exit timing statistics
Existing KVM statistics are either just counters (kvm_stat) reported for
KVM generally or trace based aproaches like kvm_trace.
For KVM on powerpc we had the need to track the timings of the different exit
types. While this could be achieved parsing data created with a kvm_trace
extension this adds too much overhead (at least on embedded PowerPC) slowing
down the workloads we wanted to measure.

Therefore this patch adds a in-kernel exit timing statistic to the powerpc kvm
code. These statistic is available per vm&vcpu under the kvm debugfs directory.
As this statistic is low, but still some overhead it can be enabled via a
.config entry and should be off by default.

Since this patch touched all powerpc kvm_stat code anyway this code is now
merged and simplified together with the exit timing statistic code (still
working with exit timing disabled in .config).

Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:41 +02:00
Hollis Blanchard
7924bd4109 KVM: ppc: directly insert shadow mappings into the hardware TLB
Formerly, we used to maintain a per-vcpu shadow TLB and on every entry to the
guest would load this array into the hardware TLB. This consumed 1280 bytes of
memory (64 entries of 16 bytes plus a struct page pointer each), and also
required some assembly to loop over the array on every entry.

Instead of saving a copy in memory, we can just store shadow mappings directly
into the hardware TLB, accepting that the host kernel will clobber these as
part of the normal 440 TLB round robin. When we do that we need less than half
the memory, and we have decreased the exit handling time for all guest exits,
at the cost of increased number of TLB misses because the host overwrites some
guest entries.

These savings will be increased on processors with larger TLBs or which
implement intelligent flush instructions like tlbivax (which will avoid the
need to walk arrays in software).

In addition to that and to the code simplification, we have a greater chance of
leaving other host userspace mappings in the TLB, instead of forcing all
subsequent tasks to re-fault all their mappings.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:09 +02:00
Hollis Blanchard
db93f5745d KVM: ppc: create struct kvm_vcpu_44x and introduce container_of() accessor
This patch doesn't yet move all 44x-specific data into the new structure, but
is the first step down that path. In the future we may also want to create a
struct kvm_vcpu_booke.

Based on patch from Liu Yu <yu.liu@freescale.com>.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:22 +02:00
Hollis Blanchard
0f55dc481e KVM: ppc: Rename "struct tlbe" to "struct kvmppc_44x_tlbe"
This will ease ports to other cores.

Also remove unused "struct kvm_tlb" while we're at it.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:51:50 +02:00
Ilya Yanok
ca9153a3a2 powerpc/44x: Support 16K/64K base page sizes on 44x
This adds support for 16k and 64k page sizes on PowerPC 44x processors.

The PGDIR table is much smaller than a page when using 16k or 64k
pages (512 and 32 bytes respectively) so we allocate the PGDIR with
kzalloc() instead of __get_free_pages().

One PTE table covers rather a large memory area when using 16k or 64k
pages (32MB or 512MB respectively), so we can easily put FIXMAP and
PKMAP in the area covered by one PTE table.

Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Vladimir Panfilov <pvr@emcraft.com>
Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-12-29 09:53:25 +11:00
Benjamin Herrenschmidt
5e696617c4 powerpc/mm: Split mmu_context handling
This splits the mmu_context handling between 32-bit hash based
processors, 64-bit hash based processors and everybody else.  This is
preliminary work for adding SMP support for BookE processors.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-12-21 14:21:15 +11:00
Paul Mackerras
597bc5c00b powerpc: Improve resolution of VDSO clock_gettime
Currently the clock_gettime implementation in the VDSO produces a
result with microsecond resolution for the cases that are handled
without a system call, i.e. CLOCK_REALTIME and CLOCK_MONOTONIC.  The
nanoseconds field of the result is obtained by computing a
microseconds value and multiplying by 1000.

This changes the code in the VDSO to do the computation for
clock_gettime with nanosecond resolution.  That means that the
resolution of the result will ultimately depend on the timebase
frequency.

Because the timestamp in the VDSO datapage (stamp_xsec, the real time
corresponding to the timebase count in tb_orig_stamp) is in units of
2^-20 seconds, it doesn't have sufficient resolution for computing a
result with nanosecond resolution.  Therefore this adds a copy of
xtime to the VDSO datapage and updates it in update_gtod() along with
the other time-related fields.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-11-06 09:49:22 +11:00
Linus Torvalds
08d19f51f0 Merge branch 'kvm-updates/2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm
* 'kvm-updates/2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm: (134 commits)
  KVM: ia64: Add intel iommu support for guests.
  KVM: ia64: add directed mmio range support for kvm guests
  KVM: ia64: Make pmt table be able to hold physical mmio entries.
  KVM: Move irqchip_in_kernel() from ioapic.h to irq.h
  KVM: Separate irq ack notification out of arch/x86/kvm/irq.c
  KVM: Change is_mmio_pfn to kvm_is_mmio_pfn, and make it common for all archs
  KVM: Move device assignment logic to common code
  KVM: Device Assignment: Move vtd.c from arch/x86/kvm/ to virt/kvm/
  KVM: VMX: enable invlpg exiting if EPT is disabled
  KVM: x86: Silence various LAPIC-related host kernel messages
  KVM: Device Assignment: Map mmio pages into VT-d page table
  KVM: PIC: enhance IPI avoidance
  KVM: MMU: add "oos_shadow" parameter to disable oos
  KVM: MMU: speed up mmu_unsync_walk
  KVM: MMU: out of sync shadow core
  KVM: MMU: mmu_convert_notrap helper
  KVM: MMU: awareness of new kvm_mmu_zap_page behaviour
  KVM: MMU: mmu_parent_walk
  KVM: x86: trap invlpg
  KVM: MMU: sync roots on mmu reload
  ...
2008-10-16 15:36:00 -07:00
Hollis Blanchard
49dd2c4928 KVM: powerpc: Map guest userspace with TID=0 mappings
When we use TID=N userspace mappings, we must ensure that kernel mappings have
been destroyed when entering userspace. Using TID=1/TID=0 for kernel/user
mappings and running userspace with PID=0 means that userspace can't access the
kernel mappings, but the kernel can directly access userspace.

The net is that we don't need to flush the TLB on privilege switches, but we do
on guest context switches (which are far more infrequent). Guest boot time
performance improvement: about 30%.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:16 +02:00
Hollis Blanchard
83aae4a809 KVM: ppc: Write only modified shadow entries into the TLB on exit
Track which TLB entries need to be written, instead of overwriting everything
below the high water mark. Typically only a single guest TLB entry will be
modified in a single exit.

Guest boot time performance improvement: about 15%.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:16 +02:00
Hollis Blanchard
20754c2495 KVM: ppc: Stop saving host TLB state
We're saving the host TLB state to memory on every exit, but never using it.
Originally I had thought that we'd want to restore host TLB for heavyweight
exits, but that could actually hurt when context switching to an unrelated host
process (i.e. not qemu).

Since this decreases the performance penalty of all exits, this patch improves
guest boot time by about 15%.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:16 +02:00
Becky Bruce
4ee7084eb1 POWERPC: Allow 32-bit hashed pgtable code to support 36-bit physical
This rearranges a bit of code, and adds support for
36-bit physical addressing for configs that use a
hashed page table.  The 36b physical support is not
enabled by default on any config - it must be
explicitly enabled via the config system.

This patch *only* expands the page table code to accomodate
large physical addresses on 32-bit systems and enables the
PHYS_64BIT config option for 86xx.  It does *not*
allow you to boot a board with more than about 3.5GB of
RAM - for that, SWIOTLB support is also required (and
coming soon).

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-09-24 16:29:44 -05:00
Paul Mackerras
1f6a93e4c3 powerpc: Make it possible to move the interrupt handlers away from the kernel
This changes the way that the exception prologs transfer control to
the handlers in 64-bit kernels with the aim of making it possible to
have the prologs separate from the main body of the kernel.  Now,
instead of computing the address of the handler by taking the top
32 bits of the paca address (to get the 0xc0000000........ part) and
ORing in something in the bottom 16 bits, we get the base address of
the kernel by doing a load from the paca and add an offset.

This also replaces an mfmsr and an ori to compute the MSR value for
the handler with a load from the paca.  That makes it unnecessary to
have a separate version of EXCEPTION_PROLOG_PSERIES that forces 64-bit
mode.

We can no longer use a direct branches in the exception prolog code,
which means that the SLB miss handlers can't branch directly to
.slb_miss_realmode any more.  Instead we have to compute the address
and do an indirect branch.  This is conditional on CONFIG_RELOCATABLE;
for non-relocatable kernels we use a direct branch as before.  (A later
change will allow CONFIG_RELOCATABLE to be set on 64-bit powerpc.)

Since the secondary CPUs on pSeries start execution in the first 0x100
bytes of real memory and then have to get to wherever the kernel is,
we can't use a direct branch to get there.  Instead this changes
__secondary_hold_spinloop from a flag to a function pointer.  When it
is set to a non-NULL value, the secondary CPUs jump to the function
pointed to by that value.

Finally this eliminates one code difference between 32-bit and 64-bit
by making __secondary_hold be the text address of the secondary CPU
spinloop rather than a function descriptor for it.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-15 11:08:08 -07:00
Michael Neuling
c6e6771b87 powerpc: Introduce VSX thread_struct and CONFIG_VSX
The layout of the new VSR registers and how they overlap on top of the
legacy FPR and VR registers is:

                   VSR doubleword 0               VSR doubleword 1
          ----------------------------------------------------------------
  VSR[0]  |             FPR[0]            |                              |
          ----------------------------------------------------------------
  VSR[1]  |             FPR[1]            |                              |
          ----------------------------------------------------------------
          |              ...              |                              |
          |              ...              |                              |
          ----------------------------------------------------------------
  VSR[30] |             FPR[30]           |                              |
          ----------------------------------------------------------------
  VSR[31] |             FPR[31]           |                              |
          ----------------------------------------------------------------
  VSR[32] |                             VR[0]                            |
          ----------------------------------------------------------------
  VSR[33] |                             VR[1]                            |
          ----------------------------------------------------------------
          |                              ...                             |
          |                              ...                             |
          ----------------------------------------------------------------
  VSR[62] |                             VR[30]                           |
          ----------------------------------------------------------------
  VSR[63] |                             VR[31]                           |
          ----------------------------------------------------------------

VSX has 64 128bit registers.  The first 32 regs overlap with the FP
registers and hence extend them with and additional 64 bits.  The
second 32 regs overlap with the VMX registers.

This commit introduces the thread_struct changes required to reflect
this register layout.  Ptrace and signals code is updated so that the
floating point registers are correctly accessed from the thread_struct
when CONFIG_VSX is enabled.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:46 +10:00
Kumar Gala
fca622c5b2 [POWERPC] 40x/Book-E: Save/restore volatile exception registers
On machines with more than one exception level any system register that
might be modified by the "normal" exception level needs to be saved and
restored on taking a higher level exception.  We already are saving
and restoring ESR and DEAR.

For critical level add SRR0/1.
For debug level add CSRR0/1 and SRR0/1.
For machine check level add DSRR0/1, CSRR0/1, and SRR0/1.

On FSL Book-E parts we always save/restore the MAS registers for critical,
debug, and machine check level exceptions.  On 44x we always save/restore
the MMUCR.

Additionally, we save and restore the ksp_limit since we have to adjust it
for each exception level.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Paul Mackerras <paulus@samba.org>
2008-06-02 14:56:35 -05:00
Linus Torvalds
867a89e0b7 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
  [RAPIDIO] Change RapidIO doorbell source and target ID field to 16-bit
  [RAPIDIO] Add RapidIO connection info print out and re-training for broken connections
  [RAPIDIO] Add serial RapidIO controller support, which includes MPC8548, MPC8641
  [RAPIDIO] Add RapidIO node probing into MPC86xx_HPCN board id table
  [RAPIDIO] Add RapidIO node into MPC8641HPCN dts file
  [RAPIDIO] Auto-probe the RapidIO system size
  [RAPIDIO] Add OF-tree support to RapidIO controller driver
  [RAPIDIO] Add RapidIO multi mport support
  [RAPIDIO] Move include/asm-ppc/rio.h to asm-powerpc
  [RAPIDIO] Add RapidIO option to kernel configuration
  [RAPIDIO] Change RIO function mpc85xx_ to fsl_
  [POWERPC] Provide walk_memory_resource() for powerpc
  [POWERPC] Update lmb data structures for hotplug memory add/remove
  [POWERPC] Hotplug memory remove notifications for powerpc
  [POWERPC] windfarm: Add PowerMac 12,1 support
  [POWERPC] Fix building of pmac32 when CONFIG_NVRAM=m
  [POWERPC] Add IRQSTACKS support on ppc32
  [POWERPC] Use __always_inline for xchg* and cmpxchg*
  [POWERPC] Add fast little-endian switch system call
2008-04-29 08:19:14 -07:00
Christoph Lameter
d4d298feea ppc/powerpc: use kbuild.h instead of defining macros in asm-offsets.c
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:30 -07:00
Kumar Gala
85218827cc [POWERPC] Add IRQSTACKS support on ppc32
This makes it possible to use separate stacks for hard and soft IRQs
on 32-bit powerpc as well as on 64-bit.  The code for 32-bit is just
the 32-bit analog of the 64-bit code.

* Added allocation and initialization of the irq stacks.  We limit the
  stacks to be in lowmem for ppc32.
* Implemented ppc32 versions of call_do_softirq() and call_handle_irq()
  to switch the stack pointers
* Reworked how we do stack overflow detection.  We now keep around the
  limit of the stack in the thread_struct and compare against the limit
  to see if we've overflowed.  We can now use this on ppc64 if desired.

[ paulus@samba.org: Fixed bug on 6xx where we need to reload r9 with the
  thread_info pointer. ]

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-29 15:57:34 +10:00
Hollis Blanchard
bbf45ba57e KVM: ppc: PowerPC 440 KVM implementation
This functionality is definitely experimental, but is capable of running
unmodified PowerPC 440 Linux kernels as guests on a PowerPC 440 host. (Only
tested with 440EP "Bamboo" guests so far, but with appropriate userspace
support other SoC/board combinations should work.)

See Documentation/powerpc/kvm_440.txt for technical details.

[stephen: build fix]

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 18:21:39 +03:00
Kumar Gala
91120cc8e0 [POWERPC] Cleanup asm-offsets.c
* Removed TI_EXECDOMAIN define as its not used anywhere
* Use STACK_INT_FRAME_SIZE to allow common define of INT_FRAME_SIZE
* Define TI_CPU on both ppc32 & ppc64 (removes an ifdef).

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-24 20:58:02 +10:00
Stephen Rothwell
3eb9cf0761 [POWERPC] iSeries: Use alternate paca structure for booting
The iSeries HV only needs the first two fields of the paca statically
initialised, so create an alternate paca that contains only those and
switch to our real paca immediately after boot.

This is in order to make the 1024 cpu patches easier since they will no
longer have to statically initialise the pacas for iSeries.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-15 21:21:25 +10:00
Roland McGrath
163dab39b5 [POWERPC] powerpc32: Remove asm-offsets ptrace cruft
These items in asm-offsets.c are not used anywhere.  This removes them.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-03-26 08:44:05 +11:00
Tony Breeds
151db1fc23 Fix compilation of powerpc asm-offsets.c with old gcc
Commit ad7f71674a ("[POWERPC] Use a
sensible default for clock_getres() in the VDSO") corrected the clock
resolution reported by the VDSO clock_getres() but introduced another
problem in that older versions of gcc (gcc-4.0 and earlier) fail to
compile the new code in arch/powerpc/kernel/asm-offsets.c.

This fixes it by introducing a new MONOTONIC_RES_NSEC define in the
generic code which is equivalent to KTIME_MONOTONIC_RES but is just an
integer constant, not a ktime union.

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-07 14:54:45 -08:00
Tony Breeds
ad7f71674a [POWERPC] Use a sensible default for clock_getres() in the VDSO
This ensures that the syscall and the (fast) vdso versions of
clock_getres() will return the same resolution.

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-02-06 16:30:00 +11:00
Kumar Gala
bee86f14d5 [POWERPC] Fix swapper_pg_dir size when CONFIG_PTE_64BIT=y on FSL_BOOKE
The size of swapper_pg_dir is 8k instead of 4k when using 64-bit PTEs
(CONFIG_PTE_64BIT).

This was reported by Cedric Hombourger <chombourger@gmail.com>

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-12-06 13:11:04 -06:00
Olof Johansson
fbe481756d [POWERPC] vdso: Fixes for cache block sizes
The current VDSO implementation is hardcoded to 128 byte cache blocks,
which are only used on IBM's 64-bit processors.

Convert it to get the cache block sizes out of vdso_data instead,
similar to how the ppc64 in-kernel cache flush does it.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-11-20 13:56:31 +11:00
Michael Neuling
4603ac180a powerpc: add scaled time accounting
This adds POWERPC specific hooks for scaled time accounting.

POWER6 includes a SPURR register.  The SPURR is based off the PURR register
but is scaled based on CPU frequency and issue rates.  This gives a more
accurate account of the instructions used per task.  The PURR and timebase
will be constant relative to the wall clock, irrespective of the CPU
frequency.

This implementation reads the SPURR register in account_system_vtime which
is only call called on context witch and hard and soft irq entry and exit.
The percentage of user and system time is then estimated using the ratio of
these accounted by the PURR.  If the SPURR is not present, the PURR read.

An earlier implementation of this patch read the SPURR whenever the PURR
was read, which included the system call entry and exit path.
Unfortunately this showed a performance regression on lmbench runs, so was
re-implemented.

I've included the lmbench results here when run bare metal on POWER6.  1st
column is the unpatch results.  2nd column is the results using the below
patch and the 3rd is the % diff of these results from the base.  4th and
5th columns are the results and % differnce from the base using the older
patch (SPURR read in syscall entry/exit path).

                              Base        Scaled-Acct     SPURR-in-syscall
                             Result      Result  % diff    Result % diff
Simple syscall:              0.3086      0.3086  0.0000    0.3452 11.8600
Simple read:                 0.4591      0.4671  1.7425    0.5044 9.86713
Simple write:                0.4364      0.4366  0.0458    0.4731 8.40971
Simple stat:                 2.0055      2.0295  1.1967    2.0669 3.06158
Simple fstat:                0.5962      0.5876  -1.442    0.6368 6.80979
Simple open/close:           3.1283      3.1009  -0.875    3.2088 2.57328
Select on 10 fd's:           0.8554      0.8457  -1.133    0.8667 1.32101
Select on 100 fd's:          3.5292      3.6329  2.9383    3.6664 3.88756
Select on 250 fd's:          7.9097      8.1881  3.5197    8.2242 3.97613
Select on 500 fd's:          15.2659     15.836  3.7357    15.873 3.97814
Select on 10 tcp fd's:       0.9576      0.9416  -1.670    0.9752 1.83792
Select on 100 tcp fd's:      7.248       7.2254  -0.311    7.2685 0.28283
Select on 250 tcp fd's:      17.7742     17.707  -0.375    17.749 -0.1406
Select on 500 tcp fd's:      35.4258     35.25   -0.496    35.286 -0.3929
Signal handler installation: 0.6131      0.6075  -0.913    0.647  5.52927
Signal handler overhead:     2.0919      2.1078  0.7600    2.1831 4.35967
Protection fault:            0.7345      0.7478  1.8107    0.8031 9.33968
Pipe latency:                33.006      16.398  -50.31    33.475 1.42368
AF_UNIX sock stream latency: 14.5093     30.910  113.03    30.715 111.692
Process fork+exit:           219.8       222.8   1.3648    229.37 4.35623
Process fork+execve:         876.14      873.28  -0.32     868.66 -0.8533
Process fork+/bin/sh -c:     2830        2876.5  1.6431    2958   4.52296
File /var/tmp/XXX write bw:  1193497     1195536 0.1708    118657 -0.5799
Pagefaults on /var/tmp/XXX:  3.1272      3.2117  2.7020    3.2521 3.99398

Also, kernel compile times show no difference with this patch applied.

[pbadari@us.ibm.com: Avoid unnecessary PURR reading]
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 14:37:28 -07:00
Stephen Rothwell
ee7a76da1e [POWERPC] Size swapper_pg_dir correctly
David Gibson pointed out that swapper_pg_dir actually need to be
PGD_TABLE_SIZE bytes long not PAGE_SIZE.  This actually saves 64k in
the bss for a kernel ppc64_defconfig built with CONFIG_PPC_64K_PAGES.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-09-19 15:25:34 +10:00