Skip to content

K
Kernel

openeuler / Kernel
1 年多 前同步成功

通知 8
Star 0
Fork 0
K
Kernel
切换分支/标签
  1. 22 9月, 2014 9 次提交
  3. 29 8月, 2014 2 次提交
  5. 22 8月, 2014 1 次提交
  7. 19 8月, 2014 1 次提交
  9. 07 8月, 2014 2 次提交
  11. 05 8月, 2014 5 次提交
  13. 31 7月, 2014 1 次提交
    • A
      KVM: PPC: PR: Handle FSCR feature deselects · 8e6afa36
      由 Alexander Graf 提交于 
      We handle FSCR feature bits (well, TAR only really today) lazily when the guest
starts using them. So when a guest activates the bit and later uses that feature
we enable it for real in hardware.

However, when the guest stops using that bit we don't stop setting it in
hardware. That means we can potentially lose a trap that the guest expects to
happen because it thinks a feature is not active.

This patch adds support to drop TAR when then guest turns it off in FSCR. While
at it it also restricts FSCR access to 64bit systems - 32bit ones don't have it.
Signed-off-by: NAlexander Graf <agraf@suse.de>
      8e6afa36
  15. 30 7月, 2014 1 次提交
  17. 29 7月, 2014 3 次提交
  19. 28 7月, 2014 15 次提交
    • A
      KVM: PPC: Handle magic page in kvmppc_ld/st · c12fb43c
      由 Alexander Graf 提交于 
      We use kvmppc_ld and kvmppc_st to emulate load/store instructions that may as
well access the magic page. Special case it out so that we can properly access
it.
Signed-off-by: NAlexander Graf <agraf@suse.de>
      c12fb43c
    • A
      KVM: PPC: Use kvm_read_guest in kvmppc_ld · c45c5514
      由 Alexander Graf 提交于 
      We have a nice and handy helper to read from guest physical address space,
so we should make use of it in kvmppc_ld as we already do for its counterpart
in kvmppc_st.
Signed-off-by: NAlexander Graf <agraf@suse.de>
      c45c5514
    • A
      KVM: PPC: Remove kvmppc_bad_hva() · 9897e88a
      由 Alexander Graf 提交于 
      We have a proper define for invalid HVA numbers. Use those instead of the
ppc specific kvmppc_bad_hva().
Signed-off-by: NAlexander Graf <agraf@suse.de>
      9897e88a
    • A
      KVM: PPC: Move kvmppc_ld/st to common code · 35c4a733
      由 Alexander Graf 提交于 
      We have enough common infrastructure now to resolve GVA->GPA mappings at
runtime. With this we can move our book3s specific helpers to load / store
in guest virtual address space to common code as well.
Signed-off-by: NAlexander Graf <agraf@suse.de>
      35c4a733
    • A
      KVM: PPC: Implement kvmppc_xlate for all targets · 7d15c06f
      由 Alexander Graf 提交于 
      We have a nice API to find the translated GPAs of a GVA including protection
flags. So far we only use it on Book3S, but there's no reason the same shouldn't
be used on BookE as well.

Implement a kvmppc_xlate() version for BookE and clean it up to make it more
readable in general.
Signed-off-by: NAlexander Graf <agraf@suse.de>
      7d15c06f
    • A
      KVM: PPC: BOOK3S: HV: Update compute_tlbie_rb to handle 16MB base page · 63fff5c1
      由 Aneesh Kumar K.V 提交于 
      When calculating the lower bits of AVA field, use the shift
count based on the base page size. Also add the missing segment
size and remove stale comment.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      63fff5c1
    • A
      KVM: PPC: Book3S: Provide different CAPs based on HV or PR mode · 7a58777a
      由 Alexander Graf 提交于 
      With Book3S KVM we can create both PR and HV VMs in parallel on the same
machine. That gives us new challenges on the CAPs we return - both have
different capabilities.

When we get asked about CAPs on the kvm fd, there's nothing we can do. We
can try to be smart and assume we're running HV if HV is available, PR
otherwise. However with the newly added VM CHECK_EXTENSION we can now ask
for capabilities directly on a VM which knows whether it's PR or HV.

With this patch I can successfully expose KVM PVINFO data to user space
in the PR case, fixing magic page mapping for PAPR guests.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
      7a58777a
    • A
      KVM: Rename and add argument to check_extension · 784aa3d7
      由 Alexander Graf 提交于 
      In preparation to make the check_extension function available to VM scope
we add a struct kvm * argument to the function header and rename the function
accordingly. It will still be called from the /dev/kvm fd, but with a NULL
argument for struct kvm *.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
      784aa3d7
    • S
      Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8 · 9678cdaa
      由 Stewart Smith 提交于 
      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: NStewart Smith <stewart@linux.vnet.ibm.com>
Acked-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      9678cdaa
    • S
      Split out struct kvmppc_vcore creation to separate function · de9bdd1a
      由 Stewart Smith 提交于 
      No code changes, just split it out to a function so that with the addition
of micro partition prefetch buffer allocation (in subsequent patch) looks
neater and doesn't require excessive indentation.
Signed-off-by: NStewart Smith <stewart@linux.vnet.ibm.com>
Acked-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      de9bdd1a
    • P
      KVM: PPC: Book3S: Make kvmppc_ld return a more accurate error indication · 1b2e33b0
      由 Paul Mackerras 提交于 
      At present, kvmppc_ld calls kvmppc_xlate, and if kvmppc_xlate returns
any error indication, it returns -ENOENT, which is taken to mean an
HPTE not found error.  However, the error could have been a segment
found (no SLB entry) or a permission error.  Similarly,
kvmppc_pte_to_hva currently does permission checking, but any error
from it is taken by kvmppc_ld to mean that the access is an emulated
MMIO access.  Also, kvmppc_ld does no execute permission checking.

This fixes these problems by (a) returning any error from kvmppc_xlate
directly, (b) moving the permission check from kvmppc_pte_to_hva
into kvmppc_ld, and (c) adding an execute permission check to kvmppc_ld.

This is similar to what was done for kvmppc_st() by commit 82ff911317c3
("KVM: PPC: Deflect page write faults properly in kvmppc_st").
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      1b2e33b0
    • P
      KVM: PPC: Book3S PR: Take SRCU read lock around RTAS kvm_read_guest() call · ef1af2e2
      由 Paul Mackerras 提交于 
      This does for PR KVM what c9438092 ("KVM: PPC: Book3S HV: Take SRCU
read lock around kvm_read_guest() call") did for HV KVM, that is,
eliminate a "suspicious rcu_dereference_check() usage!" warning by
taking the SRCU lock around the call to kvmppc_rtas_hcall().

It also fixes a return of RESUME_HOST to return EMULATE_FAIL instead,
since kvmppc_h_pr() is supposed to return EMULATE_* values.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Cc: stable@vger.kernel.org
Signed-off-by: NAlexander Graf <agraf@suse.de>
      ef1af2e2
    • A
      KVM: PPC: Book3S: Fix LPCR one_reg interface · a0840240
      由 Alexey Kardashevskiy 提交于 
      Unfortunately, the LPCR got defined as a 32-bit register in the
one_reg interface.  This is unfortunate because KVM allows userspace
to control the DPFD (default prefetch depth) field, which is in the
upper 32 bits.  The result is that DPFD always get set to 0, which
reduces performance in the guest.

We can't just change KVM_REG_PPC_LPCR to be a 64-bit register ID,
since that would break existing userspace binaries.  Instead we define
a new KVM_REG_PPC_LPCR_64 id which is 64-bit.  Userspace can still use
the old KVM_REG_PPC_LPCR id, but it now only modifies those fields in
the bottom 32 bits that userspace can modify (ILE, TC and AIL).
If userspace uses the new KVM_REG_PPC_LPCR_64 id, it can modify DPFD
as well.
Signed-off-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Cc: stable@vger.kernel.org
Signed-off-by: NAlexander Graf <agraf@suse.de>
      a0840240
    • A
      KVM: PPC: Remove 440 support · b2677b8d
      由 Alexander Graf 提交于 
      The 440 target hasn't been properly functioning for a few releases and
before I was the only one who fixes a very serious bug that indicates to
me that nobody used it before either.

Furthermore KVM on 440 is slow to the extent of unusable.

We don't have to carry along completely unused code. Remove 440 and give
us one less thing to worry about.
Signed-off-by: NAlexander Graf <agraf@suse.de>
      b2677b8d
    • B
      KVM: PPC: Booke-hv: Add one reg interface for SPRG9 · 28d2f421
      由 Bharat Bhushan 提交于 
      We now support SPRG9 for guest, so also add a one reg interface for same
Note: Changes are in bookehv code only as we do not have SPRG9 on booke-pr.
Signed-off-by: NBharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      28d2f421