summaryrefslogtreecommitdiff
path: root/cpus.c
AgeCommit message (Collapse)AuthorFilesLines
2015-09-09cpus: remove tcg_halt_cond and tcg_cpu_thread globalsKONRAD Frederic1-9/+6
This hides the tcg_halt_cond and tcg_cpu_thread global variables inside qemu_tcg_init_vcpu. Multi-threaded TCG will need one QemuCond and one QemuThread per virtual cpu, so it's preferrable to use cpu->halt_cond and cpu->thread. Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com> Message-Id: <1439220437-23957-9-git-send-email-fred.konrad@greensocs.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-09cpus: protect work list with work_mutexPaolo Bonzini1-4/+18
Protect the list of queued work items with something other than the BQL, as a preparation for running the work items outside it. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-09tcg: signal-free qemu_cpu_kickPaolo Bonzini1-67/+22
Signals are slow and do not exist on Win32. The previous patches have done most of the legwork to introduce memory barriers (some of them were even there already for the sake of Windows!) and we can now set the flags directly in the iothread. qemu_cpu_kick_thread is not used anymore on TCG, since the TCG thread is never outside usermode while the CPU is running (not halted). Instead run the content of the signal handler (now in qemu_cpu_kick_no_halt) directly. qemu_cpu_kick_no_halt is also used in qemu_mutex_lock_iothread to avoid the overhead of qemu_cond_broadcast. Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-09use qemu_cpu_kick instead of cpu_exit or qemu_cpu_kick_threadPaolo Bonzini1-9/+8
Use the same API to trigger interruption of a CPU, no matter if under TCG or KVM. There is no difference: these calls come from the CPU thread, so the qemu_cpu_kick calls will send a signal to the running thread and it will be processed synchronously, just like a call to cpu_exit. The only difference is in the overhead, but neither call to cpu_exit (now qemu_cpu_kick) is in a hot path. Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-09tcg: synchronize exit_request and tcg_current_cpu accessesPaolo Bonzini1-4/+10
Synchronize the remaining pair of accesses in cpu_signal. These should be necessary on Windows as well, at least in theory. Probably SuspendProcess and ResumeProcess introduce some implicit memory barrier. Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-09tcg: introduce tcg_current_cpuPaolo Bonzini1-2/+3
This is already useful on Windows in order to remove tls.h, because accesses to current_cpu are done from a different thread on that platform. It will be used on POSIX platforms as soon TCG stops using signals to interrupt the execution of translated code. Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-07cpus.c: qemu_mutex_lock_iothread fix race condition at cpu thread initAníbal Limón1-1/+1
When QEMU starts the RCU thread executes qemu_mutex_lock_thread causing error "qemu:qemu_cpu_kick_thread: No such process" and exits. This isn't occur frequently but in glibc the thread id can exist and this not guarantee that the thread is on active/running state. If is inserted a sleep(1) after newthread assignment [1] the issue appears. So not make assumption that thread exist if first_cpu->thread is set then change the validation of cpu to created that is set into cpu threads (kvm, tcg, dummy). [1] https://sourceware.org/git/?p=glibc.git;a=blob;f=nptl/pthread_create.c;h=d10f4ea8004e1d8f3a268b95cc0f8d93b8d89867;hb=HEAD#l621 Cc: qemu-stable@nongnu.org Signed-off-by: Aníbal Limón <anibal.limon@linux.intel.com> Message-Id: <1441313313-3040-1-git-send-email-anibal.limon@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-14exec: drop cpu_can_do_io, just read cpu->can_do_ioPaolo Bonzini1-1/+1
After commit 626cf8f (icount: set can_do_io outside TB execution, 2014-12-08), can_do_io is set to 1 if not executing code. It is no longer necessary to make this assumption in cpu_can_do_io. It is also possible to remove the use_icount test, simply by never setting cpu->can_do_io to 0 unless use_icount is true. With these changes cpu_can_do_io boils down to a read of cpu->can_do_io. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-24rcu: actually register threads that have RCU read-side critical sectionsPaolo Bonzini1-0/+6
Otherwise, grace periods are detected too early! Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-09cpu-exec: Purge all uses of ENV_GET_CPU()Peter Crosthwaite1-2/+1
Remove un-needed usages of ENV_GET_CPU() by converting the APIs to use CPUState pointers and retrieving the env_ptr as minimally needed. Scripted conversion for target-* change: for I in target-*/cpu.h; do sed -i \ 's/\(^int cpu_[^_]*_exec(\)[^ ][^ ]* \*s);$/\1CPUState *cpu);/' \ $I; done Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
2015-07-09cpu: Change tcg_cpu_exec() arg to cpu, not envPeter Crosthwaite1-4/+3
The sole caller of this function navigates the cpu->env_ptr only for this function to take it back the cpu pointer straight away. Pass in cpu pointer instead and grab the env pointer locally in the function. Removes a core code usage of ENV_GET_CPU(). Reviewed-by: Andreas Färber <afaerber@suse.de> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
2015-07-01main-loop: introduce qemu_mutex_iothread_lockedPaolo Bonzini1-0/+9
This function will be used to avoid recursive locking of the iothread lock whenever address_space_rw/ld*/st* are called with the BQL held, which is almost always the case. Tracking whether the iothread is owned is very cheap (just use a TLS variable) but requires some care because now the lock must always be taken with qemu_mutex_lock_iothread(). Previously this wasn't the case. Outside TCG mode this is not a problem. In TCG mode, we need to be careful and avoid the "prod out of compiled code" step if already in a VCPU thread. This is easily done with a check on current_cpu, i.e. qemu_in_vcpu_thread(). Hopefully, multithreaded TCG will get rid of the whole logic to kick VCPUs whenever an I/O event occurs! Cc: Frederic Konrad <fred.konrad@greensocs.com> Message-Id: <1434646046-27150-3-git-send-email-pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-01main-loop: use qemu_mutex_lock_iothread consistentlyPaolo Bonzini1-3/+7
The next patch will require the BQL to be always taken with qemu_mutex_lock_iothread(), while right now this isn't the case. Outside TCG mode this is not a problem. In TCG mode, we need to be careful and avoid the "prod out of compiled code" step if already in a VCPU thread. This is easily done with a check on current_cpu, i.e. qemu_in_vcpu_thread(). Hopefully, multithreaded TCG will get rid of the whole logic to kick VCPUs whenever an I/O event occurs! Cc: Frederic Konrad <fred.konrad@greensocs.com> Message-Id: <1434646046-27150-2-git-send-email-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-22qerror: Move #include out of qerror.hMarkus Armbruster1-0/+1
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22qerror: Clean up QERR_ macros to expand into a single stringMarkus Armbruster1-4/+4
These macros expand into error class enumeration constant, comma, string. Unclean. Has been that way since commit 13f59ae. The error class is always ERROR_CLASS_GENERIC_ERROR since the previous commit. Clean up as follows: * Prepend every use of a QERR_ macro by ERROR_CLASS_GENERIC_ERROR, and delete it from the QERR_ macro. No change after preprocessing. * Rewrite error_set(ERROR_CLASS_GENERIC_ERROR, ...) into error_setg(...). Again, no change after preprocessing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-12migration: Use normal VMStateDescriptions for SubsectionsJuan Quintela1-7/+4
We create optional sections with this patch. But we already have optional subsections. Instead of having two mechanism that do the same, we can just generalize it. For subsections we just change: - Add a needed function to VMStateDescription - Remove VMStateSubsection (after removal of the needed function it is just a VMStateDescription) - Adjust the whole tree, moving the needed function to the corresponding VMStateDescription Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-06-05icount: print a warning if there is no more deadline in sleep=no modeVictor CLEMENT1-0/+5
While qemu is running in sleep=no mode, a warning will be printed when no timer deadline is set. As this mode is intended for getting deterministic virtual time, if no timer is set on the virtual clock this determinism is broken. Signed-off-by: Victor CLEMENT <victor.clement@openwide.fr> Message-Id: <1432912446-9811-4-git-send-email-victor.clement@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05icount: add sleep parameter to the icount option to set icount_sleep modeVictor CLEMENT1-0/+9
The 'sleep' parameter sets the icount_sleep mode, which is enabled by default. To disable it, add the 'sleep=no' parameter (or 'nosleep') to the qemu -icount option. Signed-off-by: Victor CLEMENT <victor.clement@openwide.fr> Message-Id: <1432912446-9811-3-git-send-email-victor.clement@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05icount: implement a new icount_sleep mode toggleing real-time cpu sleepVictor CLEMENT1-26/+44
When the icount_sleep mode is disabled, the QEMU_VIRTUAL_CLOCK runs at the maximum possible speed by warping the sleep times of the virtual cpu to the soonest clock deadline. The virtual clock will be updated only according the instruction counter. Signed-off-by: Victor CLEMENT <victor.clement@openwide.fr> Message-Id: <1432912446-9811-2-git-send-email-victor.clement@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-14qmp: Add qom_path field to query-cpus commandEduardo Habkost1-0/+1
This will allow clients to query additional information directly using qom-get on the CPU objects. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-04-30cpus: use first_cpu macro instead of QTAILQ_FIRST(&cpus)Emilio G. Cota1-1/+1
Signed-off-by: Emilio G. Cota <cota@braap.org> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-03-25cpus: Don't kick un-realized cpus.Peter Crosthwaite1-1/+1
following a464982499b2f637f6699e3d03e0a9d2e0b5288b, it's now possible for there to be attempts to take the BQL before CPUs have been realized in cases where a machine model inits peripherals before the first CPU. BQL lock aquisition kicks the first_cpu, leading to a segfault if this happens pre-realize. Guard the CPU kick routine to perform no action for a CPU that doesn't exist or doesn't have a thread yet. There was a fix to this with commit 6b49809c597331803ea941eadda813e5bb4e8fe2, but the check there misses the case where the CPU has been inited and not realized. Strengthen the check to make sure that the first_cpu has a thread (i.e. it is realized) before allowing the kick. Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Message-Id: <1427107689-6946-1-git-send-email-peter.crosthwaite@xilinx.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-18profiler: Reenable built-in profilerAlexey Kardashevskiy1-1/+1
2ed1ebcf6 "timer: replace time() with QEMU_CLOCK_HOST" broke compile when configured with --enable-profiler. Turned out the profiler has been broken for a while. This does s/qemu_time/tcg_time/ as the profiler only works in a TCG mode. This also fixes the compile error. This changes profile_getclock() to return nanoseconds rather than CPU ticks as the "profile" HMP command prints seconds and there is no platform-independent way to get ticks-per-second rate. Since TCG is quite slow and get_clock() returns nanoseconds (fine enough), this should not affect precision much. This removes unused qemu_time_start and tlb_flush_time. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Message-Id: <1426478258-29961-1-git-send-email-aik@ozlabs.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-10memsave: Improve and disambiguate error messageBorislav Petkov1-1/+3
When requesting a size which cannot be read, the error message shows a different address which is misleading to the user and it looks like something's wrong with the address parsing. This is because the input @addr variable is incremented in the memory dumping loop: (qemu) memsave 0xffffffff8418069c 0xb00000 mem Invalid addr 0xffffffff849ffe9c specified Fix that by saving the original address and size and use them in the error message: (qemu) memsave 0xffffffff8418069c 0xb00000 mem Invalid addr 0xffffffff8418069c/size 11534336 specified Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-03-02cpus: be more paranoid in avoiding deadlocksPaolo Bonzini1-1/+5
For good measure, ensure that the following sequence: thread 1 calls qemu_mutex_lock_iothread thread 2 calls qemu_mutex_lock_iothread VCPU thread are created VCPU thread enters execution loop results in the VCPU threads letting the other two threads run and obeying iothread_requesting_mutex even if the VCPUs are not halted. To do this, check iothread_requesting_mutex before execution starts. Tested-by: Leon Alrae <leon.alrae@imgtec.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-02cpus: fix deadlock and segfault in qemu_mutex_lock_iothreadPaolo Bonzini1-4/+4
When two threads (other than the low-priority TCG VCPU thread) are competing for the iothread lock, a deadlock can happen. This is because iothread_requesting_mutex is set to false by the first thread that gets the mutex, and then the VCPU thread might never yield from the execution loop. If iothread_requesting_mutex is changed from a bool to a counter, the deadlock is fixed. However, there is another bug in qemu_mutex_lock_iothread that can be triggered by the new call_rcu thread. The bug happens if qemu_mutex_lock_iothread is called before the CPUs are created. In that case, first_cpu is NULL and the caller segfaults in qemu_mutex_lock_iothread. To fix this, just do not do the kick if first_cpu is NULL. Reported-by: Leon Alrae <leon.alrae@imgtec.com> Reported-by: Andreas Gustafsson <gson@gson.org> Tested-by: Leon Alrae <leon.alrae@imgtec.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-24Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into stagingPeter Maydell1-1/+1
- vhost-scsi: add bootindex property - RCU: fix MemoryRegion lifetime issues in PCI; document the rules; convert of AddressSpaceDispatch and RAMList - KVM: add kvm_exit reasons for aarch64 # gpg: Signature made Mon Feb 16 16:32:32 2015 GMT using RSA key ID 78C7AE83 # gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" # gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" # gpg: WARNING: This key is not certified with a trusted signature! # gpg: There is no indication that the signature belongs to the owner. # Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1 # Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83 * remotes/bonzini/tags/for-upstream: (21 commits) Convert ram_list to RCU exec: convert ram_list to QLIST cosmetic changes preparing for the following patches exec: protect mru_block with RCU rcu: add g_free_rcu rcu: introduce RCU-enabled QLIST exec: RCUify AddressSpaceDispatch exec: make iotlb RCU-friendly exec: introduce cpu_reload_memory_map docs: clarify memory region lifecycle pci: split shpc_cleanup and shpc_free pcie: remove mmconfig memory leak and wrap mmconfig update with transaction memory: keep the owner of the AddressSpace alive until do_address_space_destroy rcu: run RCU callbacks under the BQL rcu: do not let RCU callbacks pile up indefinitely vhost-scsi: set the bootable value of channel/target/lun vhost-scsi: add a property for booting vhost-scsi: expose the TYPE_FW_PATH_PROVIDER interface vhost-scsi: add bootindex property qdev: support to get a device firmware path directly ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-02-16exec: RCUify AddressSpaceDispatchPaolo Bonzini1-1/+1
Note that even after this patch, most callers of address_space_* functions must still be under the big QEMU lock, otherwise the memory region returned by address_space_translate can disappear as soon as address_space_translate returns. This will be fixed in the next part of this series. Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-16qtest: Fix deadloop by running main loop AIO context's timersFam Zheng1-0/+4
qemu_clock_run_timers() only takes care of main_loop_tlg, we shouldn't forget aio timer list groups. Currently, the qemu_clock_deadline_ns_all (a few lines above) counts all the timergroups of this clock type, including aio tlg, but we don't fire them, so they are never cleared, which makes a dead loop. For example, this function hangs when trying to drive throttled block request queue with qtest clock_step. Signed-off-by: Fam Zheng <famz@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 1421661103-29153-1-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-02-02cpu-exec: simplify init_delay_paramsPaolo Bonzini1-17/+0
With the introduction of QEMU_CLOCK_VIRTUAL_RT, the computation of sc->diff_clk can be simplified nicely: qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) - qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + cpu_get_clock_offset() = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) - (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - cpu_get_clock_offset()) = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) - (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timers_state.cpu_clock_offset) = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL_RT) Cc: Sebastian Tanase <sebastian.tanase@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-14cpus: consistently use QEMU_CLOCK_VIRTUAL_RT for icount_warp_rt timerPavel Dovgalyuk1-1/+1
Fix mismatch between timer_new_ms and timer_mod. Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-20cpu: initialize cpu->exception_index on resetPaolo Bonzini1-3/+0
This unbreaks linux-user (broken by e511b4d, cpu-exec: reset exception_index correctly, 2014-11-26). Reported-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Tested-by: Laurent Desnogues <laurent.desnogues@gmail.com> Tested-by: Eduardo Habkost <ehabkost@redhat.com> Message-id: 1418989994-17244-2-git-send-email-pbonzini@redhat.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-12-15cpus: make icount warp behave well with respect to stop/contPavel Dovgalyuk1-11/+10
This patch makes icount warp use the new QEMU_CLOCK_VIRTUAL_RT clock. This way, icount's QEMU_CLOCK_VIRTUAL will never count time during which the virtual machine is stopped. Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15icount: introduce cpu_get_icount_rawPavel Dovgalyuk1-3/+10
Separate accessing the instruction counter from the compensation for speed and halting that are introduced by qemu_icount_bias. This introduces new infrastructure used by the record/replay patches. Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15icount: set can_do_io outside TB executionPavel Dovgalyuk1-0/+3
This patch sets can_do_io function to allow reading icount within cpu-exec, but outside TB execution. Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15cpu-exec: reset exception_index correctlyPavel Dovgalyuk1-0/+3
Exception index is reset at every entry at every entry into cpu_exec() function. This may cause missing the exceptions while replaying them. This patch moves exception_index reset to the locations where they are processed. Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-16Introduce cpu_clean_all_dirtyMarcelo Tosatti1-0/+9
Introduce cpu_clean_all_dirty, to force subsequent cpu_synchronize_all_states to read in-kernel register state. Cc: qemu-stable@nongnu.org Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-11cpu: init vmstate for ticks and clock offsetPavel Dovgalyuk1-2/+6
Ticks and clock offset used by CPU timers have to be saved in vmstate. But vmstate for these fields registered only in icount mode. Missing registration leads to breaking the continuity when vmstate is loaded. This patch introduces new initialization function which fixes this. Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-01target-tricore: Add target stubs and qom-cpuBastian Koppelmann1-0/+6
Add TriCore target stubs, and QOM cpu, and Maintainer Signed-off-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Message-id: 1409572800-4116-2-git-send-email-kbastian@mail.uni-paderborn.de Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-25s390x: Migrate to new NMI interfaceAlexey Kardashevskiy1-14/+0
This implements an NMI interface for s390 and s390-ccw machines. This removes #ifdef s390 branch in qmp_inject_nmi so new s390's nmi_monitor_handler() callback is going to be used for NMI. Since nmi_monitor_handler()-calling code is platform independent, CPUState::cpu_index is used instead of S390CPU::env.cpu_num. There should not be any change in behaviour as both @cpu_index and @cpu_num are global CPU numbers. Note that s390_cpu_restart() already takes care of the specified cpu, so we don't need to schedule via async_run_on_cpu(). Since the only error s390_cpu_restart() can return is ENOSYS, convert it to QERR_UNSUPPORTED. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Alexander Graf <agraf@suse.de> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-25cpus: Define callback for QEMU "nmi" commandAlexey Kardashevskiy1-1/+2
This introduces an NMI (Non Maskable Interrupt) interface with a single nmi_monitor_handler() method. A machine or a device can implement it. This searches for an QOM object with this interface and if it is implemented, calls it. The callback implements an action required to cause debug crash dump on in-kernel debugger invocation. The callback returns Error**. This adds a nmi_monitor_handle() helper which walks through all objects to find the interface. The interface method is called for all found instances. This adds support for it in qmp_inject_nmi(). Since no architecture supports it at the moment, there is no change in behaviour. This changes inject-nmi command description for HMP and QMP. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Alexander Graf <agraf@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-07monitor: Add drift info to 'info jit'Sebastian Tanase1-0/+19
Show in 'info jit' the current delay between the host clock and the guest clock. In addition, print the maximum advance and delay of the guest compared to the host. Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr> Tested-by: Camille Bégué <camille.begue@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06cpu-exec: Add sleeping algorithmSebastian Tanase1-0/+17
The goal is to sleep qemu whenever the guest clock is in advance compared to the host clock (we use the monotonic clocks). The amount of time to sleep is calculated in the execution loop in cpu_exec. At first, we tried to approximate at each for loop the real time elapsed while searching for a TB (generating or retrieving from cache) and executing it. We would then approximate the virtual time corresponding to the number of virtual instructions executed. The difference between these 2 values would allow us to know if the guest is in advance or delayed. However, the function used for measuring the real time (qemu_clock_get_ns(QEMU_CLOCK_REALTIME)) proved to be very expensive. We had an added overhead of 13% of the total run time. Therefore, we modified the algorithm and only take into account the difference between the 2 clocks at the begining of the cpu_exec function. During the for loop we try to reduce the advance of the guest only by computing the virtual time elapsed and sleeping if necessary. The overhead is thus reduced to 3%. Even though this method still has a noticeable overhead, it no longer is a bottleneck in trying to achieve a better guest frequency for which the guest clock is faster than the host one. As for the the alignement of the 2 clocks, with the first algorithm the guest clock was oscillating between -1 and 1ms compared to the host clock. Using the second algorithm we notice that the guest is 5ms behind the host, which is still acceptable for our use case. The tests where conducted using fio and stress. The host machine in an i5 CPU at 3.10GHz running Debian Jessie (kernel 3.12). The guest machine is an arm versatile-pb built with buildroot. Currently, on our test machine, the lowest icount we can achieve that is suitable for aligning the 2 clocks is 6. However, we observe that the IO tests (using fio) are slower than the cpu tests (using stress). Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr> Tested-by: Camille Bégué <camille.begue@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06icount: Add align option to icountSebastian Tanase1-7/+12
The align option is used for activating the align algorithm in order to synchronise the host clock and the guest clock. Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr> Tested-by: Camille Bégué <camille.begue@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06icount: Add QemuOpts for icountSebastian Tanase1-1/+9
Make icount parameter use QemuOpts style options in order to easily add other suboptions. Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr> Tested-by: Camille Bégué <camille.begue@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06icount: Fix virtual clock start value on ARMSebastian Tanase1-1/+1
When using the icount option on ARM, the virtual clock starts counting at realtime clock but it should start at 0. The reason why the virtual clock starts at realtime clock is because the first time we call qemu_clock_warp (which calls icount_warp_rt) in tcg_exec_all, qemu_icount_bias (which is part of the virtual time computation mechanism) will increment by realtime - vm_clock_warp_start, with vm_clock_warp_start being 0 (see icount_warp_rt in cpus.c). By changing the value of vm_clock_warp_start from 0 to -1, the first time we call qemu_clock_warp which calls icount_warp_rt, we will return immediatly because icount_warp_rt first checks if vm_clock_warp_start is -1 and if it's the case it returns. Therefore, qemu_icount_bias will first be incremented by the value of a virtual timer deadline when the virtual cpu goes from active to inactive. The virtual time will start at 0 and increment based on the instruction counter when the vcpu is active or the qemu_icount_bias value when inactive. Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06timer: add cpu_icount_to_ns function.KONRAD Frederic1-1/+6
This adds cpu_icount_to_ns function which is needed for reverse execution. It returns the time for a specific instruction. Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06migration: migrate icount fields.KONRAD Frederic1-0/+27
This fixes a bug where qemu_icount and qemu_icount_bias are not migrated. It adds a subsection "timer/icount" to vmstate_timers so icount is migrated only when needed. Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06icount: put icount variables into TimerState.KONRAD Frederic1-13/+16
This puts qemu_icount and qemu_icount_bias into TimerState structure to allow them to be migrated. Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-23qapi event: convert STOPWenchao Xia1-1/+3
Signed-off-by: Wenchao Xia <wenchaoqemu@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>