summaryrefslogtreecommitdiffstats
path: root/arch/s390/kvm
Commit message (Collapse)AuthorAgeFilesLines
* KVM: halt_polling: provide a way to qualify wakeups during pollChristian Borntraeger2016-05-133-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some wakeups should not be considered a sucessful poll. For example on s390 I/O interrupts are usually floating, which means that _ALL_ CPUs would be considered runnable - letting all vCPUs poll all the time for transactional like workload, even if one vCPU would be enough. This can result in huge CPU usage for large guests. This patch lets architectures provide a way to qualify wakeups if they should be considered a good/bad wakeups in regard to polls. For s390 the implementation will fence of halt polling for anything but known good, single vCPU events. The s390 implementation for floating interrupts does a wakeup for one vCPU, but the interrupt will be delivered by whatever CPU checks first for a pending interrupt. We prefer the woken up CPU by marking the poll of this CPU as "good" poll. This code will also mark several other wakeup reasons like IPI or expired timers as "good". This will of course also mark some events as not sucessful. As KVM on z runs always as a 2nd level hypervisor, we prefer to not poll, unless we are really sure, though. This patch successfully limits the CPU usage for cases like uperf 1byte transactional ping pong workload or wakeup heavy workload like OLTP while still providing a proper speedup. This also introduced a new vcpu stat "halt_poll_no_tuning" that marks wakeups that are considered not good for polling. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Radim Krčmář <rkrcmar@redhat.com> (for an earlier version) Cc: David Matlack <dmatlack@google.com> Cc: Wanpeng Li <kernellwp@gmail.com> [Rename config symbol. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: s390: Populate mask of non-hypervisor managed facility bitsAlexander Yarygin2016-05-091-3/+16
| | | | | | | | | | | | | | | | | When a guest is initializing, KVM provides facility bits that can be successfully used by the guest. It's done by applying kvm_s390_fac_list_mask mask on host facility bits stored by the STFLE instruction. Facility bits can be one of two kinds: it's either a hypervisor managed bit or non-hypervisor managed. The hardware provides information which bits need special handling. Let's automatically passthrough to guests new facility bits, that don't require hypervisor support. Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* KVM: s390: Enable all facility bits that are known good for passthroughAlexander Yarygin2016-05-091-2/+2
| | | | | | | | | Some facility bits are in a range that is defined to be "ok for guests without any necessary hypervisor changes". Enable those bits. Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* KVM: s390: force ibc into valid rangeDavid Hildenbrand2016-05-091-1/+11
| | | | | | | | | | | | Some hardware variants will round the ibc value up/down themselves, others will report a validity intercept. Let's always round it up/down. This patch will also make sure that the ibc is set to 0 in case we don't have ibc support (lowest_ibc == 0). Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* KVM: s390: cleanup cpuid handlingDavid Hildenbrand2016-05-092-9/+10
| | | | | | | | | We only have one cpuid for all VCPUs, so let's directly use the one in the cpu model. Also always store it directly as u64, no need for struct cpuid. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* KVM: s390: enable SRS only if enabled for the guestDavid Hildenbrand2016-05-092-1/+9
| | | | | | | | | If we don't have SIGP SENSE RUNNING STATUS enabled for the guest, let's not enable interpretation so we can correctly report an invalid order. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* KVM: s390: enable PFMFI only if guest has EDAT1David Hildenbrand2016-05-091-1/+2
| | | | | | | | | | Only enable PFMF interpretation if the necessary facility (EDAT1) is available, otherwise the pfmf handler in priv.c will inject an exception Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* KVM: s390: support NQ only if the facility is enabled for the guestDavid Hildenbrand2016-05-041-2/+3
| | | | | | | | | While we can not fully fence of the Nonquiescing Key-Setting facility, we should as try our best to hide it. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* KVM: s390: cmma: don't check entry contentDavid Hildenbrand2016-05-041-11/+3Star
| | | | | | | | | | | | | | | | | | We should never inject an exception after we manually rewound the PSW (to retry the ESSA instruction in this case). This will mess up the PSW. So this never worked and therefore never really triggered. Looking at the details, we don't even have to perform any validity checks. 1. Bits 52-63 of an entry are stored as 0 by the hardware. 2. We are dealing with absolute addresses but only check for the prefix starting at address 0. This isn't correct and doesn't make much sense, cpus could still zap the prefix of other cpus. But as prefix pages cannot be swapped out without a notifier being called for the affected VCPU, a zap can never remove a protected prefix. Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* KVM: s390: add clear I/O irq operation for FLICHalil Pasic2016-04-201-0/+25
| | | | | | | | | | | | | | | | | | | Introduce a FLIC operation for clearing I/O interrupts for a subchannel. Rationale: According to the platform specification, pending I/O interruption requests have to be revoked in certain situations. For instance, according to the Principles of Operation (page 17-27), a subchannel put into the installed parameters initialized state is in the same state as after an I/O system reset (just parameters possibly changed). This implies that any I/O interrupts for that subchannel are no longer pending (as I/O system resets clear I/O interrupts). Therefore, we need an interface to clear pending I/O interrupts. Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
* KVM: s390: implement has_attr for FLICHalil Pasic2016-04-201-0/+17
| | | | | | | | | | | HAS_ATTR is useful for determining the supported attributes; let's implement it. Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2016-03-165-3/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: - Add the CPU id for the new z13s machine - Add a s390 specific XOR template for RAID-5 checksumming based on the XC instruction. Remove all other alternatives, XC is always faster - The merge of our four different stack tracers into a single one - Tidy up the code related to page tables, several large inline functions are now out-of-line. Bloat-o-meter reports ~11K text size reduction - A binary interface for the priviledged CLP instruction to retrieve the hardware view of the installed PCI functions - Improvements for the dasd format code - Bug fixes and cleanups * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (31 commits) s390/pci: enforce fmb page boundary rule s390: fix floating pointer register corruption (again) s390/cpumf: add missing lpp magic initialization s390: Fix misspellings in comments s390/mm: split arch/s390/mm/pgtable.c s390/mm: uninline pmdp_xxx functions from pgtable.h s390/mm: uninline ptep_xxx functions from pgtable.h s390/pci: add ioctl interface for CLP s390: Use pr_warn instead of pr_warning s390/dasd: remove casts to dasd_*_private s390/dasd: Refactor dasd format functions s390/dasd: Simplify code in format logic s390/dasd: Improve dasd format code s390/percpu: remove this_cpu_cmpxchg_double_4 s390/cpumf: Improve guest detection heuristics s390/fault: merge report_user_fault implementations s390/dis: use correct escape sequence for '%' character s390/kvm: simplify set_guest_storage_key s390/oprofile: add z13/z13s model numbers s390: add z13s model number to z13 elf platform ...
| * s390: Fix misspellings in commentsAdam Buchbinder2016-03-081-2/+2
| | | | | | | | | | | | Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * s390/mm: split arch/s390/mm/pgtable.cMartin Schwidefsky2016-03-084-1/+5
| | | | | | | | | | | | | | | | | | The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * s390/mm: uninline ptep_xxx functions from pgtable.hMartin Schwidefsky2016-03-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2016-03-167-175/+369
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM updates from Paolo Bonzini: "One of the largest releases for KVM... Hardly any generic changes, but lots of architecture-specific updates. ARM: - VHE support so that we can run the kernel at EL2 on ARMv8.1 systems - PMU support for guests - 32bit world switch rewritten in C - various optimizations to the vgic save/restore code. PPC: - enabled KVM-VFIO integration ("VFIO device") - optimizations to speed up IPIs between vcpus - in-kernel handling of IOMMU hypercalls - support for dynamic DMA windows (DDW). s390: - provide the floating point registers via sync regs; - separated instruction vs. data accesses - dirty log improvements for huge guests - bugfixes and documentation improvements. x86: - Hyper-V VMBus hypercall userspace exit - alternative implementation of lowest-priority interrupts using vector hashing (for better VT-d posted interrupt support) - fixed guest debugging with nested virtualizations - improved interrupt tracking in the in-kernel IOAPIC - generic infrastructure for tracking writes to guest memory - currently its only use is to speedup the legacy shadow paging (pre-EPT) case, but in the future it will be used for virtual GPUs as well - much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (217 commits) KVM: x86: remove eager_fpu field of struct kvm_vcpu_arch KVM: x86: disable MPX if host did not enable MPX XSAVE features arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit arm64: KVM: vgic-v3: Reset LRs at boot time arm64: KVM: vgic-v3: Do not save an LR known to be empty arm64: KVM: vgic-v3: Save maintenance interrupt state only if required arm64: KVM: vgic-v3: Avoid accessing ICH registers KVM: arm/arm64: vgic-v2: Make GICD_SGIR quicker to hit KVM: arm/arm64: vgic-v2: Only wipe LRs on vcpu exit KVM: arm/arm64: vgic-v2: Reset LRs at boot time KVM: arm/arm64: vgic-v2: Do not save an LR known to be empty KVM: arm/arm64: vgic-v2: Move GICH_ELRSR saving to its own function KVM: arm/arm64: vgic-v2: Save maintenance interrupt state only if required KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers KVM: s390: allocate only one DMA page per VM KVM: s390: enable STFLE interpretation only if enabled for the guest KVM: s390: wake up when the VCPU cpu timer expires KVM: s390: step the VCPU timer while in enabled wait KVM: s390: protect VCPU cpu timer with a seqcount KVM: s390: step VCPU cpu timer during kvm_run ioctl ...
| * | KVM: s390: allocate only one DMA page per VMDavid Hildenbrand2016-03-083-40/+26Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can fit the 2k for the STFLE interpretation and the crypto control block into one DMA page. As we now only have to allocate one DMA page, we can clean up the code a bit. As a nice side effect, this also fixes a problem with crycbd alignment in case special allocation debug options are enabled, debugged by Sascha Silbe. Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: enable STFLE interpretation only if enabled for the guestDavid Hildenbrand2016-03-081-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | Not setting the facility list designation disables STFLE interpretation, this is what we want if the guest was told to not have it. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: wake up when the VCPU cpu timer expiresDavid Hildenbrand2016-03-081-13/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the VCPU cpu timer expires, we have to wake up just like when the ckc triggers. For now, setting up a cpu timer in the guest and going into enabled wait will never lead to a wakeup. This patch fixes this problem. Just as for the ckc, we have to take care of waking up too early. We have to recalculate the sleep time and go back to sleep. Please note that the timer callback calls kvm_s390_get_cpu_timer() from interrupt context. As the timer is canceled when leaving handle_wait(), and we don't do any VCPU cpu timer writes/updates in that function, we can be sure that we will never try to read the VCPU cpu timer from the same cpu that is currentyl updating the timer (deadlock). Reported-by: Sascha Silbe <silbe@linux.vnet.ibm.com> Tested-by: Sascha Silbe <silbe@linux.vnet.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: step the VCPU timer while in enabled waitDavid Hildenbrand2016-03-082-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The cpu timer is a mean to measure task execution time. We want to account everything for a VCPU for which it is responsible. Therefore, if the VCPU wants to sleep, it shall be accounted for it. We can easily get this done by not disabling cpu timer accounting when scheduled out while sleeping because of enabled wait. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: protect VCPU cpu timer with a seqcountDavid Hildenbrand2016-03-081-8/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For now, only the owning VCPU thread (that has loaded the VCPU) can get a consistent cpu timer value when calculating the delta. However, other threads might also be interested in a more recent, consistent value. Of special interest will be the timer callback of a VCPU that executes without having the VCPU loaded and could run in parallel with the VCPU thread. The cpu timer has a nice property: it is only updated by the owning VCPU thread. And speaking about accounting, a consistent value can only be calculated by looking at cputm_start and the cpu timer itself in one shot, otherwise the result might be wrong. As we only have one writing thread at a time (owning VCPU thread), we can use a seqcount instead of a seqlock and retry if the VCPU refreshed its cpu timer. This avoids any heavy locking and only introduces a counter update/check plus a handful of smp_wmb(). The owning VCPU thread should never have to retry on reads, and also for other threads this might be a very rare scenario. Please note that we have to use the raw_* variants for locking the seqcount as lockdep will produce false warnings otherwise. The rq->lock held during vcpu_load/put is also acquired from hardirq context. Lockdep cannot know that we avoid potential deadlocks by disabling preemption and thereby disable concurrent write locking attempts (via vcpu_put/load). Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: step VCPU cpu timer during kvm_run ioctlDavid Hildenbrand2016-03-081-2/+74
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Architecturally we should only provide steal time if we are scheduled away, and not if the host interprets a guest exit. We have to step the guest CPU timer in these cases. In the first shot, we will step the VCPU timer only during the kvm_run ioctl. Therefore all time spent e.g. in interception handlers or on irq delivery will be accounted for that VCPU. We have to take care of a few special cases: - Other VCPUs can test for pending irqs. We can only report a consistent value for the VCPU thread itself when adding the delta. - We have to take care of STP sync, therefore we have to extend kvm_clock_sync() and disable preemption accordingly - During any call to disable/enable/start/stop we could get premeempted and therefore get start/stop calls. Therefore we have to make sure we don't get into an inconsistent state. Whenever a VCPU is scheduled out, sleeping, in user space or just about to enter the SIE, the guest cpu timer isn't stepped. Please note that all primitives are prepared to be called from both environments (cpu timer accounting enabled or not), although not completely used in this patch yet (e.g. kvm_s390_set_cpu_timer() will never be called while cpu timer accounting is enabled). Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: abstract access to the VCPU cpu timerDavid Hildenbrand2016-03-083-10/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | We want to manually step the cpu timer in certain scenarios in the future. Let's abstract any access to the cpu timer, so we can hide the complexity internally. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: store cpu id in vcpu->cpu when scheduled inDavid Hildenbrand2016-03-081-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | By storing the cpu id, we have a way to verify if the current cpu is owning a VCPU. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: bail out early on fatal signal in dirty loggingChristian Borntraeger2016-02-101-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A KVM_GET_DIRTY_LOG ioctl might take a long time. This can result in fatal signals seemingly being ignored. Lets bail out during the dirty bit sync, if a fatal signal is pending. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: do not block CPU on dirty loggingChristian Borntraeger2016-02-101-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When doing dirty logging on huge guests (e.g.600GB) we sometimes get rcu stall timeouts with backtraces like [ 2753.194083] ([<0000000000112fb2>] show_trace+0x12a/0x130) [ 2753.194092] [<0000000000113024>] show_stack+0x6c/0xe8 [ 2753.194094] [<00000000001ee6a8>] rcu_pending+0x358/0xa48 [ 2753.194099] [<00000000001f20cc>] rcu_check_callbacks+0x84/0x168 [ 2753.194102] [<0000000000167654>] update_process_times+0x54/0x80 [ 2753.194107] [<00000000001bdb5c>] tick_sched_handle.isra.16+0x4c/0x60 [ 2753.194113] [<00000000001bdbd8>] tick_sched_timer+0x68/0x90 [ 2753.194115] [<0000000000182a88>] __run_hrtimer+0x88/0x1f8 [ 2753.194119] [<00000000001838ba>] hrtimer_interrupt+0x122/0x2b0 [ 2753.194121] [<000000000010d034>] do_extint+0x16c/0x170 [ 2753.194123] [<00000000005e206e>] ext_skip+0x38/0x3e [ 2753.194129] [<000000000012157c>] gmap_test_and_clear_dirty+0xcc/0x118 [ 2753.194134] ([<00000000001214ea>] gmap_test_and_clear_dirty+0x3a/0x118) [ 2753.194137] [<0000000000132da4>] kvm_vm_ioctl_get_dirty_log+0xd4/0x1b0 [ 2753.194143] [<000000000012ac12>] kvm_vm_ioctl+0x21a/0x548 [ 2753.194146] [<00000000002b57f6>] do_vfs_ioctl+0x30e/0x518 [ 2753.194149] [<00000000002b5a9c>] SyS_ioctl+0x9c/0xb0 [ 2753.194151] [<00000000005e1ae6>] sysc_tracego+0x14/0x1a [ 2753.194153] [<000003ffb75f3972>] 0x3ffb75f3972 We should do a cond_resched in here. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: do not take mmap_sem on dirty log queryChristian Borntraeger2016-02-101-2/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Dirty log query can take a long time for huge guests. Holding the mmap_sem for very long times can cause some unwanted latencies. Turns out that we do not need to hold the mmap semaphore. We hold the slots_lock for gfn->hva translation and walk the page tables with that address, so no need to look at the VMAs. KVM also holds a reference to the mm, which should prevent other things going away. During the walk we take the necessary ptl locks. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: instruction-fetching exceptions on SIE faultsDavid Hildenbrand2016-02-101-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On instruction-fetch exceptions, we have to forward the PSW by any valid ilc and correctly use that ilc when injecting the irq. Injection will already take care of rewinding the PSW if we injected a nullifying program irq, so we don't need special handling prior to injection. Until now, autodetection would have guessed an ilc of 0. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: provide prog irq ilc on SIE faultsDavid Hildenbrand2016-02-101-4/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On SIE faults, the ilc cannot be detected automatically, as the icptcode is 0. The ilc indicated in the program irq will always be 0. Therefore we have to manually specify the ilc in order to tell the guest which ilen was used when forwarding the PSW. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: irq delivery should not rely on icptcodeDavid Hildenbrand2016-02-102-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Program irq injection during program irq intercepts is the last candidates that injects nullifying irqs and relies on delivery to do the right thing. As we should not rely on the icptcode during any delivery (because that value will not be migrated), let's add a flag, telling prog IRQ delivery to not rewind the PSW in case of nullifying prog IRQs. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: clean up prog irq injection on prog irq icptsDavid Hildenbrand2016-02-101-21/+20Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __extract_prog_irq() is used only once for getting the program check data in one place. Let's combine it with an injection function to avoid a memset and to prevent misuse on injection by simplifying the interface to only have the VCPU as parameter. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: read the correct opcode on SIE faultsDavid Hildenbrand2016-02-101-2/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | Let's use our fresh new function read_guest_instr() to access guest storage via the correct addressing schema. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: gaccess: implement instruction fetching modeDavid Hildenbrand2016-02-102-4/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When an instruction is to be fetched, special handling applies to secondary-space mode and access-register mode. The instruction is to be fetched from primary space. We can easily support this by selecting the right asce for translation. Access registers will never be used during translation, so don't include them in the interface. As we only want to read from the current PSW address for now, let's also hide that detail. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: gaccess: introduce access modesDavid Hildenbrand2016-02-105-35/+43
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We will need special handling when fetching instructions, so let's introduce new guest access modes GACC_FETCH and GACC_STORE instead of a write flag. An additional patch will then introduce GACC_IFETCH. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: migration / injection of prog irq ilcDavid Hildenbrand2016-02-101-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have to migrate the program irq ilc and someday we will have to specify the ilc without KVM trying to autodetect the value. Let's reuse one of the spare fields in our program irq that should always be set to 0 by user space. Because we also want to make use of 0 ilcs ("not available"), we need a validity indicator. If no valid ilc is given, we try to autodetect the ilc via the current icptcode and icptstatus + parameter and store the valid ilc in the irq structure. This has a nice effect: QEMU's making use of KVM_S390_IRQ / KVM_S390_SET_IRQ_STATE / KVM_S390_GET_IRQ_STATE for migration will directly migrate the ilc without any changes. Please note that we use bit 0 as validity and bit 1,2 for the ilc, so by applying the ilc mask we directly get the ilen which is usually what we work with. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: PSW forwarding / rewinding / ilc reworkDavid Hildenbrand2016-02-105-36/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have some confusion about ilc vs. ilen in our current code. So let's correctly use the term ilen when dealing with (ilc << 1). Program irq injection didn't take care of the correct ilc in case of irqs triggered by EXECUTE functions, let's provide one function kvm_s390_get_ilen() to take care of all that. Also, manually specifying in intercept handlers the size of the instruction (and sometimes overwriting that value for EXECUTE internally) doesn't make too much sense. So also provide the functions: - kvm_s390_retry_instr to retry the currently intercepted instruction - kvm_s390_rewind_psw to rewind the PSW without internal overwrites - kvm_s390_forward_psw to forward the PSW Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: sync of fp registers via kvm_runDavid Hildenbrand2016-02-101-5/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As we already store the floating point registers in the vector save area in floating point register format when we don't have MACHINE_HAS_VX, we can directly expose them to user space using a new sync flag. The floating point registers will be valid when KVM_SYNC_FPRS is set. The fpc will also be valid when KVM_SYNC_FPRS is set. Either KVM_SYNC_FPRS or KVM_SYNC_VRS will be enabled, never both. Let's also change two positions where we access vrs, making the code easier to read and one comment superfluous. Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: allow sync of fp registers via vregsDavid Hildenbrand2016-02-101-1/+4
| |/ | | | | | | | | | | | | | | | | | | | | | | | | If we have MACHINE_HAS_VX, the floating point registers are stored in the vector register format, event if the guest isn't enabled for vector registers. So we can allow KVM_SYNC_VRS as soon as MACHINE_HAS_VX is available. This can in return be used by user space to support floating point registers via struct kvm_run when the machine has vector registers. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | Merge branch 'sched-core-for-linus' of ↵Linus Torvalds2016-03-151-2/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes in this cycle are: - Make schedstats a runtime tunable (disabled by default) and optimize it via static keys. As most distributions enable CONFIG_SCHEDSTATS=y due to its instrumentation value, this is a nice performance enhancement. (Mel Gorman) - Implement 'simple waitqueues' (swait): these are just pure waitqueues without any of the more complex features of full-blown waitqueues (callbacks, wake flags, wake keys, etc.). Simple waitqueues have less memory overhead and are faster. Use simple waitqueues in the RCU code (in 4 different places) and for handling KVM vCPU wakeups. (Peter Zijlstra, Daniel Wagner, Thomas Gleixner, Paul Gortmaker, Marcelo Tosatti) - sched/numa enhancements (Rik van Riel) - NOHZ performance enhancements (Rik van Riel) - Various sched/deadline enhancements (Steven Rostedt) - Various fixes (Peter Zijlstra) - ... and a number of other fixes, cleanups and smaller enhancements" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (29 commits) sched/cputime: Fix steal_account_process_tick() to always return jiffies sched/deadline: Remove dl_new from struct sched_dl_entity Revert "kbuild: Add option to turn incompatible pointer check into error" sched/deadline: Remove superfluous call to switched_to_dl() sched/debug: Fix preempt_disable_ip recording for preempt_disable() sched, time: Switch VIRT_CPU_ACCOUNTING_GEN to jiffy granularity time, acct: Drop irq save & restore from __acct_update_integrals() acct, time: Change indentation in __acct_update_integrals() sched, time: Remove non-power-of-two divides from __acct_update_integrals() sched/rt: Kick RT bandwidth timer immediately on start up sched/debug: Add deadline scheduler bandwidth ratio to /proc/sched_debug sched/debug: Move sched_domain_sysctl to debug.c sched/debug: Move the /sys/kernel/debug/sched_features file setup into debug.c sched/rt: Fix PI handling vs. sched_setscheduler() sched/core: Remove duplicated sched_group_set_shares() prototype sched/fair: Consolidate nohz CPU load update code sched/fair: Avoid using decay_load_missed() with a negative value sched/deadline: Always calculate end of period on sched_yield() sched/cgroup: Fix cgroup entity load tracking tear-down rcu: Use simple wait queues where possible in rcutree ...
| * | KVM: Use simple waitqueue for vcpu->wqMarcelo Tosatti2016-02-251-2/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The problem: On -rt, an emulated LAPIC timer instances has the following path: 1) hard interrupt 2) ksoftirqd is scheduled 3) ksoftirqd wakes up vcpu thread 4) vcpu thread is scheduled This extra context switch introduces unnecessary latency in the LAPIC path for a KVM guest. The solution: Allow waking up vcpu thread from hardirq context, thus avoiding the need for ksoftirqd to be scheduled. Normal waitqueues make use of spinlocks, which on -RT are sleepable locks. Therefore, waking up a waitqueue waiter involves locking a sleeping lock, which is not allowed from hard interrupt context. cyclictest command line: This patch reduces the average latency in my tests from 14us to 11us. Daniel writes: Paolo asked for numbers from kvm-unit-tests/tscdeadline_latency benchmark on mainline. The test was run 1000 times on tip/sched/core 4.4.0-rc8-01134-g0905f04: ./x86-run x86/tscdeadline_latency.flat -cpu host with idle=poll. The test seems not to deliver really stable numbers though most of them are smaller. Paolo write: "Anything above ~10000 cycles means that the host went to C1 or lower---the number means more or less nothing in that case. The mean shows an improvement indeed." Before: min max mean std count 1000.000000 1000.000000 1000.000000 1000.000000 mean 5162.596000 2019270.084000 5824.491541 20681.645558 std 75.431231 622607.723969 89.575700 6492.272062 min 4466.000000 23928.000000 5537.926500 585.864966 25% 5163.000000 1613252.750000 5790.132275 16683.745433 50% 5175.000000 2281919.000000 5834.654000 23151.990026 75% 5190.000000 2382865.750000 5861.412950 24148.206168 max 5228.000000 4175158.000000 6254.827300 46481.048691 After min max mean std count 1000.000000 1000.00000 1000.000000 1000.000000 mean 5143.511000 2076886.10300 5813.312474 21207.357565 std 77.668322 610413.09583 86.541500 6331.915127 min 4427.000000 25103.00000 5529.756600 559.187707 25% 5148.000000 1691272.75000 5784.889825 17473.518244 50% 5160.000000 2308328.50000 5832.025000 23464.837068 75% 5172.000000 2393037.75000 5853.177675 24223.969976 max 5222.000000 3922458.00000 6186.720500 42520.379830 [Patch was originaly based on the swait implementation found in the -rt tree. Daniel ported it to mainline's version and gathered the benchmark numbers for tscdeadline_latency test.] Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: linux-rt-users@vger.kernel.org Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1455871601-27484-4-git-send-email-wagi@monom.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* / KVM: s390: correct fprs on SIGP (STOP AND) STORE STATUSDavid Hildenbrand2016-03-081-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | With MACHINE_HAS_VX, we convert the floating point registers from the vector registeres when storing the status. For other VCPUs, these are stored to vcpu->run->s.regs.vrs, but we are using current->thread.fpu.vxrs, which resolves to the currently loaded VCPU. So kvm_s390_store_status_unloaded() currently writes the wrong floating point registers (converted from the vector registers) when called from another VCPU on a z13. This is only the case for old user space not handling SIGP STORE STATUS and SIGP STOP AND STORE STATUS, but relying on the kernel implementation. All other calls come from the loaded VCPU via kvm_s390_store_status(). Fixes: 9abc2a08a7d6 (KVM: s390: fix memory overwrites when vx is disabled) Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Cc: stable@vger.kernel.org # v4.4+ Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2016-01-301-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: "An optimization for irq-restore, the SSM instruction is quite a bit slower than an if-statement and a STOSM. The copy_file_range system all is added. Cleanup for PCI and CIO. And a couple of bug fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/cio: update measurement characteristics s390/cio: ensure consistent measurement state s390/cio: fix measurement characteristics memleak s390/zcrypt: Fix cryptographic device id in kernel messages s390/pci: remove iomap sanity checks s390/pci: set error state for unusable functions s390/pci: fix bar check s390/pci: resize iomap s390/pci: improve ZPCI_* macros s390/pci: provide ZPCI_ADDR macro s390/pci: adjust IOMAP_MAX_ENTRIES s390/numa: move numa_init_late() from device to arch_initcall s390: remove all usages of PSW_ADDR_INSN s390: remove all usages of PSW_ADDR_AMODE s390: wire up copy_file_range syscall s390: remove superfluous memblock_alloc() return value checks s390/numa: allocate memory with correct alignment s390/irqflags: optimize irq restore s390/mm: use TASK_MAX_SIZE where applicable
| * s390: remove all usages of PSW_ADDR_INSNHeiko Carstens2016-01-191-2/+2
| | | | | | | | | | | | | | | | | | | | | | Yet another leftover from the 31 bit era. The usual operation "y = x & PSW_ADDR_INSN" with the PSW_ADDR_INSN mask is a nop for CONFIG_64BIT. Therefore remove all usages and hope the code is a bit less confusing. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
* | KVM: s390: fix memory overwrites when vx is disabledDavid Hildenbrand2016-01-261-83/+43Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel now always uses vector registers when available, however KVM has special logic if support is really enabled for a guest. If support is disabled, guest_fpregs.fregs will only contain memory for the fpu. The kernel, however, will store vector registers into that area, resulting in crazy memory overwrites. Simply extending that area is not enough, because the format of the registers also changes. We would have to do additional conversions, making the code even more complex. Therefore let's directly use one place for the vector/fpu registers + fpc (in kvm_run). We just have to convert the data properly when accessing it. This makes current code much easier. Please note that vector/fpu registers are now always stored to vcpu->run->s.regs.vrs. Although this data is visible to QEMU and used for migration, we only guarantee valid values to user space when KVM_SYNC_VRS is set. As that is only the case when we have vector register support, we are on the safe side. Fixes: b5510d9b68c3 ("s390/fpu: always enable the vector facility if it is available") Cc: stable@vger.kernel.org # v4.4 d9a3a09af54d s390/kvm: remove dependency on struct save_area definition Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> [adopt to d9a3a09af54d]
* | KVM: s390: Enable the KVM-VFIO deviceDong Jia Shi2016-01-262-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | The KVM-VFIO device is used by the QEMU VFIO device. It is used to record the list of in-use VFIO groups so that KVM can manipulate them. While we don't need this on s390 currently, let's try to be like everyone else. Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: fix guest fprs memory leakDavid Hildenbrand2016-01-261-1/+4
|/ | | | | | | | | | | | fprs is never freed, therefore resulting in a memory leak if kvm_vcpu_init() fails or the vcpu is destroyed. Fixes: 9977e886cbbc ("s390/kernel: lazy restore fpu registers") Cc: stable@vger.kernel.org # v4.3+ Reported-by: Eric Farman <farman@linux.vnet.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2016-01-133-18/+18
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: "Among the traditional bug fixes and cleanups are some improvements: - A tool to generated the facility lists, generating the bit fields by hand has been a source of bugs in the past - The spinlock loop is reordered to avoid bursts of hypervisor calls - Add support for the open-for-business interface to the service element - The get_cpu call is added to the vdso - A set of tracepoints is defined for the common I/O layer - The deprecated sclp_cpi module is removed - Update default configuration" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (56 commits) s390/sclp: fix possible control register corruption s390: fix normalization bug in exception table sorting s390/configs: update default configurations s390/vdso: optimize getcpu system call s390: drop smp_mb in vdso_init s390: rename struct _lowcore to struct lowcore s390/mem_detect: use unsigned longs s390/ptrace: get rid of long longs in psw_bits s390/sysinfo: add missing SYSIB 1.2.2 multithreading fields s390: get rid of CONFIG_SCHED_MC and CONFIG_SCHED_BOOK s390/Kconfig: remove pointless 64 bit dependencies s390/dasd: fix failfast for disconnected devices s390/con3270: testing return kzalloc retval s390/hmcdrv: constify hmcdrv_ftp_ops structs s390/cio: add NULL test s390/cio: Change I/O instructions from inline to normal functions s390/cio: Introduce common I/O layer tracepoints s390/cio: Consolidate inline assemblies and related data definitions s390/cio: Fix incorrect xsch opcode specification s390/cio: Remove unused inline assemblies ...
| * s390: rename struct _lowcore to struct lowcoreHeiko Carstens2016-01-112-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | Finally get rid of the leading underscore. I tried this already two or three years ago, however Michael Holzheu objected since this would break the crash utility (again). However Michael integrated support for the new name into the crash utility back then, so it doesn't break if the name will be changed now. So finally get rid of the ever confusing leading underscore. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * s390/kvm: remove dependency on struct save_area definitionMartin Schwidefsky2015-11-271-15/+15
| | | | | | | | | | | | | | Replace the offsets based on the struct area_area with the offset constants from asm-offsets.c based on the struct _lowcore. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* | KVM: s390: implement the RI support of guestFan Zhang2016-01-071-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds runtime instrumentation support for KVM guest. We need to setup a save area for the runtime instrumentation-controls control block(RICCB) and implement the necessary interfaces to live migrate the guest settings. We setup the sie control block in a way, that the runtime instrumentation instructions of a guest are handled by hardware. We also add a capability KVM_CAP_S390_RI to make this feature opt-in as it needs migration support. Signed-off-by: Fan Zhang <zhangfan@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-07-11 10:18:56 +0200