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POWER8"
This reverts commit 9678cdaae939 ("Use the POWER8 Micro Partition
Prefetch Engine in KVM HV on POWER8") because the original commit had
multiple, partly self-cancelling bugs, that could cause occasional
memory corruption.
In fact the logmpp instruction was incorrectly using register r0 as the
source of the buffer address and operation code, and depending on what
was in r0, it would either do nothing or corrupt the 64k page pointed to
by r0.
The logmpp instruction encoding and the operation code definitions could
be corrected, but then there is the problem that there is no clearly
defined way to know when the hardware has finished writing to the
buffer.
The original commit attempted to work around this by aborting the
write-out before starting the prefetch, but this is ineffective in the
case where the virtual core is now executing on a different physical
core from the one where the write-out was initiated.
These problems plus advice from the hardware designers not to use the
function (since the measured performance improvement from using the
feature was actually mostly negative), mean that reverting the code is
the best option.
Fixes: 9678cdaae939 ("Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8")
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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When compiling the KVM code for POWER with "make C=1", sparse
complains about functions missing proper prototypes and a 64-bit
constant missing the ULL prefix. Let's fix this by making the
functions static or by including the proper header with the
prototypes, and by appending a ULL prefix to the constant
PPC_MPPE_ADDRESS_MASK.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
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Add the asm ICSWX and ICSWEPX opcodes. Add definitions for the
Coprocessor Request structures needed to use the icswx calls to
coprocessors. Add icswx() function to perform the ICSWX asm
using the provided Coprocessor Command Word value and
Coprocessor Request Block structure.
This is required for communication with the NX-842 coprocessor on
a PowerNV system.
Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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Conflicts:
drivers/net/usb/asix_common.c
drivers/net/usb/sr9800.c
drivers/net/usb/usbnet.c
include/linux/usb/usbnet.h
net/ipv4/tcp_ipv4.c
net/ipv6/tcp_ipv6.c
The TCP conflicts were overlapping changes. In 'net' we added a
READ_ONCE() to the socket cached RX route read, whilst in 'net-next'
Eric Dumazet touched the surrounding code dealing with how mini
sockets are handled.
With USB, it's a case of the same bug fix first going into net-next
and then I cherry picked it back into net.
Signed-off-by: David S. Miller <davem@davemloft.net>
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Since we can now use hypervisor doorbells for host IPIs, this makes
sure we clear the host IPI flag when taking a doorbell interrupt, and
clears any pending doorbell IPI in pnv_smp_cpu_kill_self() (as we
already do for IPIs sent via the XICS interrupt controller). Otherwise
if there did happen to be a leftover pending doorbell interrupt for
an offline CPU thread for any reason, it would prevent that thread from
going into a power-saving mode; it would instead keep waking up because
of the interrupt.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull second batch of powerpc updates from Michael Ellerman:
"The highlight is the series that reworks the idle management on
powernv, which allows us to use deeper idle states on those machines.
There's the fix from Anton for the "BUG at kernel/smpboot.c:134!"
problem.
An i2c driver for powernv. This is acked by Wolfram Sang, and he
asked that we take it through the powerpc tree.
A fix for audit from rgb at Red Hat, acked by Paul Moore who is one of
the audit maintainers.
A patch from Ben to export the symbol map of our OPAL firmware as a
sysfs file, so that tools can use it.
Also some CXL fixes, a couple of powerpc perf fixes, a fix for
smt-enabled, and the patch to add __force to get_user() so we can use
bitwise types"
* tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux:
powerpc/powernv: Ignore smt-enabled on Power8 and later
powerpc/uaccess: Allow get_user() with bitwise types
powerpc/powernv: Expose OPAL firmware symbol map
powernv/powerpc: Add winkle support for offline cpus
powernv/cpuidle: Redesign idle states management
powerpc/powernv: Enable Offline CPUs to enter deep idle states
powerpc/powernv: Switch off MMU before entering nap/sleep/rvwinkle mode
i2c: Driver to expose PowerNV platform i2c busses
powerpc: add little endian flag to syscall_get_arch()
power/perf/hv-24x7: Use kmem_cache_free() instead of kfree
powerpc/perf/hv-24x7: Use per-cpu page buffer
cxl: Unmap MMIO regions when detaching a context
cxl: Add timeout to process element commands
cxl: Change contexts_lock to a mutex to fix sleep while atomic bug
powerpc: Secondary CPUs must set cpu_callin_map after setting active and online
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Winkle is a deep idle state supported in power8 chips. A core enters
winkle when all the threads of the core enter winkle. In this state
power supply to the entire chiplet i.e core, private L2 and private L3
is turned off. As a result it gives higher powersavings compared to
sleep.
But entering winkle results in a total hypervisor state loss. Hence the
hypervisor context has to be preserved before entering winkle and
restored upon wake up.
Power-on Reset Engine (PORE) is a dedicated engine which is responsible
for powering on the chiplet during wake up. It can be programmed to
restore the register contests of a few specific registers. This patch
uses PORE to restore register state wherever possible and uses stack to
save and restore rest of the necessary registers.
With hypervisor state restore things fall under three categories-
per-core state, per-subcore state and per-thread state. To manage this,
extend the infrastructure introduced for sleep. Mainly we add a paca
variable subcore_sibling_mask. Using this and the core_idle_state we can
distingush first thread in core and subcore.
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Add BPF extension SKF_AD_PKTTYPE to ppc JIT to load
skb->pkt_type field.
Before:
[ 88.262622] test_bpf: #11 LD_IND_NET 86 97 99 PASS
[ 88.265740] test_bpf: #12 LD_PKTTYPE 109 107 PASS
After:
[ 80.605964] test_bpf: #11 LD_IND_NET 44 40 39 PASS
[ 80.607370] test_bpf: #12 LD_PKTTYPE 9 9 PASS
CC: Alexei Starovoitov<alexei.starovoitov@gmail.com>
CC: Michael Ellerman<mpe@ellerman.id.au>
Cc: Matt Evans <matt@ozlabs.org>
Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org>
v2: Added test rusults
Signed-off-by: David S. Miller <davem@davemloft.net>
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Pull second round of KVM changes from Paolo Bonzini:
"Here are the PPC and ARM changes for KVM, which I separated because
they had small conflicts (respectively within KVM documentation, and
with 3.16-rc changes). Since they were all within the subsystem, I
took care of them.
Stephen Rothwell reported some snags in PPC builds, but they are all
fixed now; the latest linux-next report was clean.
New features for ARM include:
- KVM VGIC v2 emulation on GICv3 hardware
- Big-Endian support for arm/arm64 (guest and host)
- Debug Architecture support for arm64 (arm32 is on Christoffer's todo list)
And for PPC:
- Book3S: Good number of LE host fixes, enable HV on LE
- Book3S HV: Add in-guest debug support
This release drops support for KVM on the PPC440. As a result, the
PPC merge removes more lines than it adds. :)
I also included an x86 change, since Davidlohr tied it to an
independent bug report and the reporter quickly provided a Tested-by;
there was no reason to wait for -rc2"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (122 commits)
KVM: Move more code under CONFIG_HAVE_KVM_IRQFD
KVM: nVMX: fix "acknowledge interrupt on exit" when APICv is in use
KVM: nVMX: Fix nested vmexit ack intr before load vmcs01
KVM: PPC: Enable IRQFD support for the XICS interrupt controller
KVM: Give IRQFD its own separate enabling Kconfig option
KVM: Move irq notifier implementation into eventfd.c
KVM: Move all accesses to kvm::irq_routing into irqchip.c
KVM: irqchip: Provide and use accessors for irq routing table
KVM: Don't keep reference to irq routing table in irqfd struct
KVM: PPC: drop duplicate tracepoint
arm64: KVM: fix 64bit CP15 VM access for 32bit guests
KVM: arm64: GICv3: mandate page-aligned GICV region
arm64: KVM: GICv3: move system register access to msr_s/mrs_s
KVM: PPC: PR: Handle FSCR feature deselects
KVM: PPC: HV: Remove generic instruction emulation
KVM: PPC: BOOKEHV: rename e500hv_spr to bookehv_spr
KVM: PPC: Remove DCR handling
KVM: PPC: Expose helper functions for data/inst faults
KVM: PPC: Separate loadstore emulation from priv emulation
KVM: PPC: Handle magic page in kvmppc_ld/st
...
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The general idea is that each core will release all of its
threads into the secondary thread startup code, which will
eventually wait in the secondary core holding area, for the
appropriate bit in the PACA to be set. The kick_cpu function
pointer will set that bit in the PACA, and thus "release"
the core/thread to boot. We also need to do a few things that
U-Boot normally does for CPUs (like enable branch prediction).
Signed-off-by: Andy Fleming <afleming@freescale.com>
[scottwood@freescale.com: various changes, including only enabling
threads if Linux wants to kick them]
Signed-off-by: Scott Wood <scottwood@freescale.com>
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The POWER8 processor has a Micro Partition Prefetch Engine, which is
a fancy way of saying "has way to store and load contents of L2 or
L2+MRU way of L3 cache". We initiate the storing of the log (list of
addresses) using the logmpp instruction and start restore by writing
to a SPR.
The logmpp instruction takes parameters in a single 64bit register:
- starting address of the table to store log of L2/L2+L3 cache contents
- 32kb for L2
- 128kb for L2+L3
- Aligned relative to maximum size of the table (32kb or 128kb)
- Log control (no-op, L2 only, L2 and L3, abort logout)
We should abort any ongoing logging before initiating one.
To initiate restore, we write to the MPPR SPR. The format of what to write
to the SPR is similar to the logmpp instruction parameter:
- starting address of the table to read from (same alignment requirements)
- table size (no data, until end of table)
- prefetch rate (from fastest possible to slower. about every 8, 16, 24 or
32 cycles)
The idea behind loading and storing the contents of L2/L3 cache is to
reduce memory latency in a system that is frequently swapping vcores on
a physical CPU.
The best case scenario for doing this is when some vcores are doing very
cache heavy workloads. The worst case is when they have about 0 cache hits,
so we just generate needless memory operations.
This implementation just does L2 store/load. In my benchmarks this proves
to be useful.
Benchmark 1:
- 16 core POWER8
- 3x Ubuntu 14.04LTS guests (LE) with 8 VCPUs each
- No split core/SMT
- two guests running sysbench memory test.
sysbench --test=memory --num-threads=8 run
- one guest running apache bench (of default HTML page)
ab -n 490000 -c 400 http://localhost/
This benchmark aims to measure performance of real world application (apache)
where other guests are cache hot with their own workloads. The sysbench memory
benchmark does pointer sized writes to a (small) memory buffer in a loop.
In this benchmark with this patch I can see an improvement both in requests
per second (~5%) and in mean and median response times (again, about 5%).
The spread of minimum and maximum response times were largely unchanged.
benchmark 2:
- Same VM config as benchmark 1
- all three guests running sysbench memory benchmark
This benchmark aims to see if there is a positive or negative affect to this
cache heavy benchmark. Although due to the nature of the benchmark (stores) we
may not see a difference in performance, but rather hopefully an improvement
in consistency of performance (when vcore switched in, don't have to wait
many times for cachelines to be pulled in)
The results of this benchmark are improvements in consistency of performance
rather than performance itself. With this patch, the few outliers in duration
go away and we get more consistent performance in each guest.
benchmark 3:
- same 3 guests and CPU configuration as benchmark 1 and 2.
- two idle guests
- 1 guest running STREAM benchmark
This scenario also saw performance improvement with this patch. On Copy and
Scale workloads from STREAM, I got 5-6% improvement with this patch. For
Add and triad, it was around 10% (or more).
benchmark 4:
- same 3 guests as previous benchmarks
- two guests running sysbench --memory, distinctly different cache heavy
workload
- one guest running STREAM benchmark.
Similar improvements to benchmark 3.
benchmark 5:
- 1 guest, 8 VCPUs, Ubuntu 14.04
- Host configured with split core (SMT8, subcores-per-core=4)
- STREAM benchmark
In this benchmark, we see a 10-20% performance improvement across the board
of STREAM benchmark results with this patch.
Based on preliminary investigation and microbenchmarks
by Prerna Saxena <prerna@linux.vnet.ibm.com>
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
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Currently DIVWU stands for *signed* divw opcode:
7d 2a 4b 96 divwu r9,r10,r9
7d 2a 4b d6 divw r9,r10,r9
Use the *unsigned* divw opcode for DIVWU.
Suggested-by: Vassili Karpov <av1474@comtv.ru>
Reviewed-by: Vassili Karpov <av1474@comtv.ru>
Signed-off-by: Vladimir Murzin <murzin.v@gmail.com>
Acked-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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This enables the Berkeley Packet Filter JIT compiler
for the PowerPC running in 64bit Little Endian.
Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Reserved fields of the sync instruction have been used for other
instructions (e.g. lwsync). On processors that do not support variants
of the sync instruction, emulate it by executing a sync to subsume the
effect of the intended instruction.
Signed-off-by: James Yang <James.Yang@freescale.com>
[scottwood@freescale.com: whitespace and subject line fix]
Signed-off-by: Scott Wood <scottwood@freescale.com>
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save/restore
The elements within VSX loads and stores are big endian ordered
regardless of endianness. Our VSX context save/restore code uses
lxvd2x and stxvd2x which is a 2x doubleword operation. This means
the two doublewords will be swapped and we have to perform another
swap to undo it.
We need to do this on save and restore.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Opcode and xopcode are useful definitions not just for KVM. Move these
definitions to asm/ppc-opcode.h for public use.
Also add the opcodes for LHAUX and LWZUX.
Signed-off-by: Jia Hongtao <hongtao.jia@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
[scottwood@freesacle.com: update commit message and rebase]
Signed-off-by: Scott Wood <scottwood@freescale.com>
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POWER8 allows read and write of the DSCR in userspace. We added
kernel emulation so applications could always use the instructions
regardless of the CPU type.
Unfortunately there are two SPRs for the DSCR and we only added
emulation for the privileged one. Add code to match the non
privileged one.
A simple test was created to verify the fix:
http://ozlabs.org/~anton/junkcode/user_dscr_test.c
Without the patch we get a SIGILL and it passes with the patch.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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This patch adds new POWER8 instruction encoding for reading
and clearing Branch History Rolling Buffer entries. The new
instruction 'mfbhrbe' (move from branch history rolling buffer
entry) is used to read BHRB buffer entries and instruction
'clrbhrb' (clear branch history rolling buffer) is used to
clear the entire buffer. The instruction 'clrbhrb' has straight
forward encoding. But the instruction encoding format for
reading the BHRB entries is like 'mfbhrbe RT, BHRBE' where it
takes two arguments, i.e the index for the BHRB buffer entry to
read and a general purpose register to put the value which was
read from the buffer entry.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Here we define the new instructions we need for transactional memory in the
kernel. This is so we can support compiling with binutils that don't support
the new transactional memory instructions.
Transactional memory results in two sets of architected state (GPRs/VSRs
etc).
treclaim allows us to read the checkpointed state (from the tbegin) so that we
can store it away on a context switch. It does this by overwriting the exiting
architected state, so you have to save that away before you treclaim. treclaim
will also abort a transaction, so you can give a register value which contains
an abort reason.
trecheckpoint allows us to inject into the checkpointed state as if it were at
the tbegin. It does this by copying the current architected state into the
checkpointed state.
Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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There are a few key differences between doorbells on server compared
with embedded that we care about on Linux, namely:
- We have a new msgsndp instruction for directed privileged doorbells.
msgsnd is used for directed hypervisor doorbells.
- The tag we use in the instruction is the Thread Identification
Register of the recipient thread (since server doorbells can only
occur between threads within a single core), and is only 7 bits wide.
- A new message type is introduced for server doorbells (none of the
existing book3e message types are currently supported on book3s).
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Tested-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc update from Benjamin Herrenschmidt:
"The main highlight is probably some base POWER8 support. There's more
to come such as transactional memory support but that will wait for
the next one.
Overall it's pretty quiet, or rather I've been pretty poor at picking
things up from patchwork and reviewing them this time around and Kumar
no better on the FSL side it seems..."
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (73 commits)
powerpc+of: Rename and fix OF reconfig notifier error inject module
powerpc: mpc5200: Add a3m071 board support
powerpc/512x: don't compile any platform DIU code if the DIU is not enabled
powerpc/mpc52xx: use module_platform_driver macro
powerpc+of: Export of_reconfig_notifier_[register,unregister]
powerpc/dma/raidengine: add raidengine device
powerpc/iommu/fsl: Add PAMU bypass enable register to ccsr_guts struct
powerpc/mpc85xx: Change spin table to cached memory
powerpc/fsl-pci: Add PCI controller ATMU PM support
powerpc/86xx: fsl_pcibios_fixup_bus requires CONFIG_PCI
drivers/virt: the Freescale hypervisor driver doesn't need to check MSR[GS]
powerpc/85xx: p1022ds: Use NULL instead of 0 for pointers
powerpc: Disable relocation on exceptions when kexecing
powerpc: Enable relocation on during exceptions at boot
powerpc: Move get_longbusy_msecs into hvcall.h and remove duplicate function
powerpc: Add wrappers to enable/disable relocation on exceptions
powerpc: Add set_mode hcall
powerpc: Setup relocation on exceptions for bare metal systems
powerpc: Move initial mfspr LPCR out of __init_LPCR
powerpc: Add relocation on exception vector handlers
...
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This patch is a follow-up for patch "filter: add XOR instruction for use
with X/K" that implements BPF PowerPC JIT parts for the BPF XOR operation.
Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch>
Cc: Matt Evans <matt@ozlabs.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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There are many cases that Semiconductor is misspelled. The patch
fix these typos.
Signed-off-by: Li Yang <leoli@freescale.com>
Acked-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Don't use 47x only #defines for TLBIVAX or ICBT, supply and use helpers
in ppc-opcode.h
This fixes a compile breakage.
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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On POWER6 and POWER7 if the input operand to an instruction is a
denormalised single precision binary floating point value we can take
a denormalisation exception where it's expected that the hypervisor
(HV=1) will fix up the inputs before the instruction is run.
This adds code to handle this denormalisation exception for POWER6 and
POWER7.
It also add a CONFIG_PPC_DENORMALISATION option and sets it in
pseries/ppc64_defconfig.
This is useful on bare metal systems only. Based on patch from Milton
Miller.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Some macros use RA where when RA=R0 the values is 0, so make this
the enforced mnemonic in the macro.
Idea suggested by Andreas Schwab.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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R0 is special since it'll be 0.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Enforce the use of R0-R31 in macros where possible now we have all the
fixes in.
R0-R31 macros are removed here so that can't be used anymore. They
should not be defined anywhere.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Now have ___PPC_RA/B/S/T we can use it in some places. These are
places where we can't use the existing defines which will soon enforce
R0-R31 usage.
The macros being changed here are being used in inline asm, which
can't convert to enforce the R0-R31 usage.
bpf_jit uses a mix of both generated and non-generated with the same
code, so just convert all these to use the ___PPC_R versions which
won't enforce R usage later.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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These are currently the same as __PPC_RA/B/S/T but we'll wrap them
soon.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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We need to do this so we can enforce the name of a and b in called
macros PPC_RA/B later.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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move lbz/stbciz to ppc-opcode.h.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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We are going to use these later and convert r0 to %r0 etc.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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This provides the low-level support for MMIO emulation in Book3S HV
guests. When the guest tries to map a page which is not covered by
any memslot, that page is taken to be an MMIO emulation page. Instead
of inserting a valid HPTE, we insert an HPTE that has the valid bit
clear but another hypervisor software-use bit set, which we call
HPTE_V_ABSENT, to indicate that this is an absent page. An
absent page is treated much like a valid page as far as guest hcalls
(H_ENTER, H_REMOVE, H_READ etc.) are concerned, except of course that
an absent HPTE doesn't need to be invalidated with tlbie since it
was never valid as far as the hardware is concerned.
When the guest accesses a page for which there is an absent HPTE, it
will take a hypervisor data storage interrupt (HDSI) since we now set
the VPM1 bit in the LPCR. Our HDSI handler for HPTE-not-present faults
looks up the hash table and if it finds an absent HPTE mapping the
requested virtual address, will switch to kernel mode and handle the
fault in kvmppc_book3s_hv_page_fault(), which at present just calls
kvmppc_hv_emulate_mmio() to set up the MMIO emulation.
This is based on an earlier patch by Benjamin Herrenschmidt, but since
heavily reworked.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
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An implementation of a code generator for BPF programs to speed up packet
filtering on PPC64, inspired by Eric Dumazet's x86-64 version.
Filter code is generated as an ABI-compliant function in module_alloc()'d mem
with stackframe & prologue/epilogue generated if required (simple filters don't
need anything more than an li/blr). The filter's local variables, M[], live in
registers. Supports all BPF opcodes, although "complicated" loads from negative
packet offsets (e.g. SKF_LL_OFF) are not yet supported.
There are a couple of further optimisations left for future work; many-pass
assembly with branch-reach reduction and a register allocator to push M[]
variables into volatile registers would improve the code quality further.
This currently supports big-endian 64-bit PowerPC only (but is fairly simple
to port to PPC32 or LE!).
Enabled in the same way as x86-64:
echo 1 > /proc/sys/net/core/bpf_jit_enable
Or, enabled with extra debug output:
echo 2 > /proc/sys/net/core/bpf_jit_enable
Signed-off-by: Matt Evans <matt@ozlabs.org>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The DSCR (aka Data Stream Control Register) is supported on some
server PowerPC chips and allow some control over the prefetch
of data streams.
This patch allows the value to be specified per thread by emulating
the corresponding mfspr and mtspr instructions. Children of such
threads inherit the value. Other threads use a default value that
can be specified in sysfs - /sys/devices/system/cpu/dscr_default.
If a thread starts with non default value in the sysfs entry,
all children threads inherit this non default value even if
the sysfs value is changed later.
Signed-off-by: Alexey Kardashevskiy <aik@au1.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Wakeup comes from the system reset handler with a potential loss of
the non-hypervisor CPU state. We save the non-volatile state on the
stack and a pointer to it in the PACA, which the system reset handler
uses to restore things
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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The popcnt instructions went into binutils relatively recently. As with a
number of other instructions, create macros and hardcode them.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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This extends the emulate_step() function to handle a large proportion
of the Book I instructions implemented on current 64-bit server
processors. The aim is to handle all the load and store instructions
used in the kernel, plus all of the instructions that appear between
l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx
and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7).
The new code can emulate user mode instructions, and checks the
effective address for a load or store if the saved state is for
user mode. It doesn't handle little-endian mode at present.
For floating-point, Altivec/VMX and VSX instructions, it checks
that the saved MSR has the enable bit for the relevant facility
set, and if so, assumes that the FP/VMX/VSX registers contain
valid state, and does loads or stores directly to/from the
FP/VMX/VSX registers, using assembly helpers in ldstfp.S.
Instructions supported now include:
* Loads and stores, including some but not all VMX and VSX instructions,
and lmw/stmw
* Atomic loads and stores (l[dw]arx, st[dw]cx.)
* Arithmetic instructions (add, subtract, multiply, divide, etc.)
* Compare instructions
* Rotate and mask instructions
* Shift instructions
* Logical instructions (and, or, xor, etc.)
* Condition register logical instructions
* mtcrf, cntlz[wd], exts[bhw]
* isync, sync, lwsync, ptesync, eieio
* Cache operations (dcbf, dcbst, dcbt, dcbtst)
The overflow-checking arithmetic instructions are not included, but
they appear not to be ever used in C code.
This uses decimal values for the minor opcodes in the switch statements
because that is what appears in the Power ISA specification, thus it is
easier to check that they are correct if they are in decimal.
If this is used to single-step an instruction where a data breakpoint
interrupt occurred, then there is the possibility that the instruction
is a lwarx or ldarx. In that case we have to be careful not to lose the
reservation until we get to the matching st[wd]cx., or we'll never make
forward progress. One alternative is to try to arrange that we can
return from interrupts and handle data breakpoint interrupts without
losing the reservation, which means not using any spinlocks, mutexes,
or atomic ops (including bitops). That seems rather fragile. The
other alternative is to emulate the larx/stcx and all the instructions
in between. This is why this commit adds support for a wide range
of integer instructions.
Signed-off-by: Paul Mackerras <paulus@samba.org>
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e500v1/v2 based chips will treat any reserved field being set in an
opcode as illegal. Thus always setting the hint in the opcode is
a bad idea.
Anton should be kept away from the powerpc opcode map.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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This patch implements the lwarx/ldarx hint bit for bit locks.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Recent versions of the PowerPC architecture added a hint bit to the larx
instructions to differentiate between an atomic operation and a lock operation:
> 0 Other programs might attempt to modify the word in storage addressed by EA
> even if the subsequent Store Conditional succeeds.
>
> 1 Other programs will not attempt to modify the word in storage addressed by
> EA until the program that has acquired the lock performs a subsequent store
> releasing the lock.
To avoid a binutils dependency this patch create macros for the extended lwarx
format and uses it in the spinlock code. To test this change I used a simple
test case that acquires and releases a global pthread mutex:
pthread_mutex_lock(&mutex);
pthread_mutex_unlock(&mutex);
On a 32 core POWER6, running 32 test threads we spend almost all our time in
the futex spinlock code:
94.37% perf [kernel] [k] ._raw_spin_lock
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|--99.95%-- ._raw_spin_lock
| |
| |--63.29%-- .futex_wake
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| |--36.64%-- .futex_wait_setup
Which is a good test for this patch. The results (in lock/unlock operations per
second) are:
before: 1538203 ops/sec
after: 2189219 ops/sec
An improvement of 42%
A 32 core POWER7 improves even more:
before: 1279529 ops/sec
after: 2282076 ops/sec
An improvement of 78%
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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This adds the opcode definitions to ppc-opcode.h for the two instructions
tlbivax and tlbsrx. as defined by Book3E 2.06
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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This adds the PowerPC 2.06 tlbie mnemonics and keeps backwards
compatibilty for CPUs before 2.06.
Only useful for bare metal systems.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Cleans up the VSX load/store instructions by moving them into
ppc-opcode.h.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Make macros more braces happy.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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This reverts commit e9965577406a2148ade97b5e0ce7c448b4ba4ef6. Our HW
guys were able to fix this so it never sees the light of day.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
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Paul Mackerras
Thomas Huth
Dan Streetman
David S. Miller
Denis Kirjanov
Linus Torvalds
Shreyas B. Prabhu
Andy Fleming
Stewart Smith
Vladimir Murzin
Philippe Bergheaud
James Yang
Anton Blanchard
Hongtao Jia
Anshuman Khandual
Michael Neuling
Ian Munsie
Daniel Borkmann
Yang Li
Tony Breeds
Matt Evans
Alexey Kardashevskiy
Benjamin Herrenschmidt
Kumar Gala
Milton Miller