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2019-06-21hax: Honor CPUState::haltedColin Xu1-1/+0
QEMU tracks whether a vcpu is halted using CPUState::halted. E.g., after initialization or reset, halted is 0 for the BSP (vcpu 0) and 1 for the APs (vcpu 1, 2, ...). A halted vcpu should not be handed to the hypervisor to run (e.g. hax_vcpu_run()). Under HAXM, Android Emulator sometimes boots into a "vcpu shutdown request" error while executing in SeaBIOS, with the HAXM driver logging a guest triple fault in vcpu 1, 2, ... at RIP 0x3. That is ultimately because the HAX accelerator asks HAXM to run those APs when they are still in the halted state. Normally, the vcpu thread for an AP will start by looping in qemu_wait_io_event(), until the BSP kicks it via a pair of IPIs (INIT followed by SIPI). But because the HAX accelerator does not honor cpu->halted, it allows the AP vcpu thread to proceed to hax_vcpu_run() as soon as it receives any kick, even if the kick does not come from the BSP. It turns out that emulator has a worker thread which periodically kicks every vcpu thread (possibly to collect CPU usage data), and if one of these kicks comes before those by the BSP, the AP will start execution from the wrong RIP, resulting in the aforementioned SMP boot failure. The solution is inspired by the KVM accelerator (credit to Chuanxiao Dong <chuanxiao.dong@intel.com> for the pointer): 1. Get rid of questionable logic that unconditionally resets cpu->halted before hax_vcpu_run(). Instead, only reset it at the right moments (there are only a few "unhalt" events). 2. Add a check for cpu->halted before hax_vcpu_run(). Note that although the non-Unrestricted Guest (!ug_platform) code path also forcibly resets cpu->halted, it is left untouched, because only the UG code path supports SMP guests. The patch is first merged to android emulator with Change-Id: I9c5752cc737fd305d7eace1768ea12a07309d716 Cc: Yu Ning <yu.ning@intel.com> Cc: Chuanxiao Dong <chuanxiao.dong@intel.com> Signed-off-by: Colin Xu <colin.xu@intel.com> Message-Id: <20190610021939.13669-1-colin.xu@intel.com>
2019-06-12Include qemu-common.h exactly where neededMarkus Armbruster1-0/+1
No header includes qemu-common.h after this commit, as prescribed by qemu-common.h's file comment. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190523143508.25387-5-armbru@redhat.com> [Rebased with conflicts resolved automatically, except for include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and net/tap-bsd.c fixed up]
2019-06-11qemu-common: Move tcg_enabled() etc. to sysemu/tcg.hMarkus Armbruster1-0/+1
Other accelerators have their own headers: sysemu/hax.h, sysemu/hvf.h, sysemu/kvm.h, sysemu/whpx.h. Only tcg_enabled() & friends sit in qemu-common.h. This necessitates inclusion of qemu-common.h into headers, which is against the rules spelled out in qemu-common.h's file comment. Move tcg_enabled() & friends into their own header sysemu/tcg.h, and adjust #include directives. Cc: Richard Henderson <rth@twiddle.net> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190523143508.25387-2-armbru@redhat.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> [Rebased with conflicts resolved automatically, except for accel/tcg/tcg-all.c]
2019-06-10cpu: Move icount_decr to CPUNegativeOffsetStateRichard Henderson1-4/+5
Amusingly, we had already ignored the comment to keep this value at the end of CPUState. This restores the minimum negative offset from TCG_AREG0 for code generation. For the couple of uses within qom/cpu.c, without NEED_CPU_H, add a pointer from the CPUState object to the IcountDecr object within CPUNegativeOffsetState. Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-05-22cpus: Initialize pseudo-random seeds for all guest cpusRichard Henderson1-0/+9
When the -seed option is given, call qemu_guest_random_seed_main, putting the subsystem into deterministic mode. Pass derived seeds to each cpu created; which is a no-op unless the subsystem is in deterministic mode. Reviewed-by: Laurent Vivier <lvivier@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-04-18qom/cpu: Simplify how CPUClass:cpu_dump_state() printsMarkus Armbruster1-1/+1
CPUClass method dump_statistics() takes an fprintf()-like callback and a FILE * to pass to it. Most callers pass fprintf() and stderr. log_cpu_state() passes fprintf() and qemu_log_file. hmp_info_registers() passes monitor_fprintf() and the current monitor cast to FILE *. monitor_fprintf() casts it right back, and is otherwise identical to monitor_printf(). The callback gets passed around a lot, which is tiresome. The type-punning around monitor_fprintf() is ugly. Drop the callback, and call qemu_fprintf() instead. Also gets rid of the type-punning, since qemu_fprintf() takes NULL instead of the current monitor cast to FILE *. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20190417191805.28198-15-armbru@redhat.com>
2019-04-18target: Simplify how the TARGET_cpu_list() printMarkus Armbruster1-2/+2
The various TARGET_cpu_list() take an fprintf()-like callback and a FILE * to pass to it. Their callers (vl.c's main() via list_cpus(), bsd-user/main.c's main(), linux-user/main.c's main()) all pass fprintf() and stdout. Thus, the flexibility provided by the (rather tiresome) indirection isn't actually used. Drop the callback, and call qemu_printf() instead. Calling printf() would also work, but would make the code unsuitable for monitor context without making it simpler. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190417191805.28198-10-armbru@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-04-18tcg: Simplify how dump_drift_info() printsMarkus Armbruster1-6/+9
dump_drift_info() takes an fprintf()-like callback and a FILE * to pass to it. Its only caller hmp_info_jit() passes monitor_fprintf() and a Monitor * cast to FILE *. monitor_fprintf() casts it right back, and is otherwise identical to monitor_printf(). The type-punning is ugly. Drop the callback, and call qemu_printf() instead. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Message-Id: <20190417191805.28198-6-armbru@redhat.com>
2019-02-26cpus: Properly release the iothread lock when killing a dummy VCPUDavid Hildenbrand1-0/+1
This enables CPU unplug under qtest. Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Greg Kurz <groug@kaod.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20190218092202.26683-2-david@redhat.com> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-02-05cpus: ignore ESRCH in qemu_cpu_kick_thread()Laurent Vivier1-1/+1
We can have a race condition between qemu_cpu_kick_thread() and qemu_kvm_cpu_thread_fn() when we hotunplug a CPU. In this case, qemu_cpu_kick_thread() can try to kick a thread that is exiting. pthread_kill() returns an error and qemu is stopped by an exit(1). qemu:qemu_cpu_kick_thread: No such process We can ignore safely this error. Signed-off-by: Laurent Vivier <lvivier@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-01-07cpus.c: Fix race condition in cpu_stop_current()Peter Maydell1-1/+2
We use cpu_stop_current() to ensure the current CPU has stopped from places like qemu_system_reset_request(). Unfortunately its current implementation has a race. It calls qemu_cpu_stop(), which sets cpu->stopped to true even though the CPU hasn't actually stopped yet. The main thread will look at the flags set by qemu_system_reset_request() and call pause_all_vcpus(). pause_all_vcpus() waits for every cpu to have cpu->stopped true, so it can continue (and we will start the system reset operation) before the vcpu thread has got back to its top level loop. Instead, just set cpu->stop and call cpu_exit(). This will cause the vcpu to exit back to the top level loop, and there (as part of the wait_io_event code) it will call qemu_cpu_stop(). This fixes bugs where the reset request appeared to be ignored or the CPU misbehaved because the reset operation started to change vcpu state while the vcpu thread was still using it. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Emilio G. Cota <cota@braap.org> Tested-by: Jaap Crezee <jaap@jcz.nl> Message-id: 20181207155911.12710-1-peter.maydell@linaro.org
2018-11-27cpus: run work items for all vCPUs if single-threadedPaolo Bonzini1-4/+8
This avoids the following I/O thread deadlock: 1) the I/O thread calls run_on_cpu for CPU 3 from a timer. single_tcg_halt_cond is signaled 2) CPU 1 is running and exits. It finds no work item and enters CPU 2 3) because the I/O thread is stuck in run_on_cpu, the round-robin kick timer never triggers, and CPU 3 never runs the work item 4) run_on_cpu never completes Reviewed-by: Emilio G. Cota <cota@braap.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-11-06icount: fix deadlock when all cpus are sleepingClement Deschamps1-0/+8
When all cpus are sleeping (e.g in WFI), to avoid a deadlock in the main_loop, wake it up in order to start the warp timer. Signed-off-by: Clement Deschamps <clement.deschamps@greensocs.com> Message-Id: <20181021142103.19014-1-clement.deschamps@greensocs.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-23Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2018-10-22' ↵Peter Maydell1-4/+4
into staging Error reporting patches for 2018-10-22 # gpg: Signature made Mon 22 Oct 2018 13:20:23 BST # gpg: using RSA key 3870B400EB918653 # gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" # gpg: aka "Markus Armbruster <armbru@pond.sub.org>" # Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653 * remotes/armbru/tags/pull-error-2018-10-22: (40 commits) error: Drop bogus "use error_setg() instead" admonitions vpc: Fail open on bad header checksum block: Clean up bdrv_img_create()'s error reporting vl: Simplify call of parse_name() vl: Fix exit status for -drive format=help blockdev: Convert drive_new() to Error vl: Assert drive_new() does not fail in default_drive() fsdev: Clean up error reporting in qemu_fsdev_add() spice: Clean up error reporting in add_channel() tpm: Clean up error reporting in tpm_init_tpmdev() numa: Clean up error reporting in parse_numa() vnc: Clean up error reporting in vnc_init_func() ui: Convert vnc_display_init(), init_keyboard_layout() to Error ui/keymaps: Fix handling of erroneous include files vl: Clean up error reporting in device_init_func() vl: Clean up error reporting in parse_fw_cfg() vl: Clean up error reporting in mon_init_func() vl: Clean up error reporting in machine_set_property() vl: Clean up error reporting in chardev_init_func() qom: Clean up error reporting in user_creatable_add_opts_foreach() ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-10-19Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into stagingPeter Maydell1-2/+2
* RTC fixes (Artem) * icount fixes (Artem) * rr fixes (Pavel, myself) * hotplug cleanup (Igor) * SCSI fixes (myself) * 4.20-rc1 KVM header update (myself) * coalesced PIO support (Peng Hao) * HVF fixes (Roman B.) * Hyper-V refactoring (Roman K.) * Support for Hyper-V IPI (Vitaly) # gpg: Signature made Fri 19 Oct 2018 12:47:58 BST # gpg: using RSA key BFFBD25F78C7AE83 # gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" # gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" # 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: (47 commits) replay: pass raw icount value to replay_save_clock target/i386: kvm: just return after migrate_add_blocker failed hyperv_testdev: add SynIC message and event testmodes hyperv: process POST_MESSAGE hypercall hyperv: add support for KVM_HYPERV_EVENTFD hyperv: process SIGNAL_EVENT hypercall hyperv: add synic event flag signaling hyperv: add synic message delivery hyperv: make overlay pages for SynIC hyperv: only add SynIC in compatible configurations hyperv: qom-ify SynIC hyperv:synic: split capability testing and setting i386: add hyperv-stub for CONFIG_HYPERV=n default-configs: collect CONFIG_HYPERV* in hyperv.mak hyperv: factor out arch-independent API into hw/hyperv hyperv: make hyperv_vp_index inline hyperv: split hyperv-proto.h into x86 and arch-independent parts hyperv: rename kvm_hv_sint_route_set_sint hyperv: make HvSintRoute reference-counted hyperv: address HvSintRoute by X86CPU pointer ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-10-19cpus hw target: Use warn_report() & friends to report warningsMarkus Armbruster1-4/+4
Calling error_report() in a function that takes an Error ** argument is suspicious. Convert a few that are actually warnings to warn_report(). While there, split a warning consisting of multiple sentences to conform to conventions spelled out in warn_report()'s contract. Cc: Alex Bennée <alex.bennee@linaro.org> Cc: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Fam Zheng <famz@redhat.com> Cc: Wei Huang <wei@redhat.com> Cc: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Markus Armbruster <armbru@redhat.com> Acked-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20181017082702.5581-5-armbru@redhat.com>
2018-10-19replay: pass raw icount value to replay_save_clockPaolo Bonzini1-2/+2
This avoids lock recursion when REPLAY_CLOCK is called inside the timers spinlock. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-18tcg: distribute tcg_time into TCG contextsEmilio G. Cota1-1/+2
When we implemented per-vCPU TCG contexts, we forgot to also distribute the tcg_time counter, which has remained as a global accessed without any serialization, leading to potentially missed counts. Fix it by distributing the field over the TCG contexts, embedding it into TCGProfile with a field called "cpu_exec_time", which is more descriptive than "tcg_time". Add a function to query this value directly, and for completeness, fill in the field in tcg_profile_snapshot, even though its callers do not use it. Signed-off-by: Emilio G. Cota <cota@braap.org> Message-Id: <20181010144853.13005-5-cota@braap.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-02cpus: fix TCG kick timer leakAlex Bennée1-2/+3
This is an alternative fix to Marc-André's original patch. Reported-by: Marc-André Lureau <marcandre.lureau@redhat.com> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20180927171724.30128-1-alex.bennee@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02replay: wake up vCPU when replayingPavel Dovgalyuk1-10/+21
In record/replay icount mode vCPU thread and iothread synchronize the execution using the checkpoints. vCPU thread processes the virtual timers and iothread processes all others. When iothread wants to wake up sleeping vCPU thread, it sends dummy queued work. Therefore it could be the following sequence of the events in record mode: - IO: sending dummy work - IO: processing timers - CPU: wakeup - CPU: clearing dummy work - CPU: processing virtual timers But due to the races in replay mode the sequence may change: - IO: sending dummy work - CPU: wakeup - CPU: clearing dummy work - CPU: sleeping again because nothing to do - IO: Processing timers - CPU: zzzz In this case vCPU will not wake up, because dummy work is not to be set up again. This patch tries to wake up the vCPU when it sleeps and the icount warp checkpoint isn't met. It means that vCPU has something to do, because there are no other reasons of non-matching warp checkpoint. Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> -- v5: improve checking that vCPU is still sleeping Message-Id: <20180912081945.3228.19776.stgit@pasha-VirtualBox> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02cpus: access .qemu_icount_bias with atomic64Emilio G. Cota1-10/+11
Signed-off-by: Emilio G. Cota <cota@braap.org> Message-Id: <20180910232752.31565-11-cota@braap.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02cpus: access .qemu_icount with atomic64Emilio G. Cota1-4/+4
Signed-off-by: Emilio G. Cota <cota@braap.org> Message-Id: <20180910232752.31565-10-cota@braap.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02cpus: take seqlock across qemu_icount updatesPaolo Bonzini1-8/+14
Even though writes of qemu_icount can safely race with reads in qemu_icount_raw, qemu_icount is also read by icount_adjust, which runs in the I/O thread. Therefore, writes do needs protection of the vm_clock_lock; for simplicity the patch protects it with both seqlock+spinlock, which we already do for hosts that lack 64-bit atomics. The bug actually predated the introduction of vm_clock_lock; cpu_update_icount would have needed the BQL before the spinlock was introduced. Reported-by: Emilio G. Cota <cota@braap.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02cpus: initialize timers_state.vm_clock_lockEmilio G. Cota1-0/+1
We forgot to initialize the spinlock introduced in 94377115b2 ("cpus: protect TimerState writes with a spinlock", 2018-08-23). Fix it. Signed-off-by: Emilio G. Cota <cota@braap.org> Message-Id: <20180903171831.15446-5-cota@braap.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-24Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-3.1-20180907' ↵Peter Maydell1-1/+0
into staging ppc patch queue 2018-09-07 Here's another pull request for qemu-3.1. No real theme here, just an assortment of various fixes. Probably the most notable thing is the removal of the ppcemb target which has been deprecated for some time now. # gpg: Signature made Fri 07 Sep 2018 08:30:02 BST # gpg: using RSA key 6C38CACA20D9B392 # gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>" # gpg: aka "David Gibson (Red Hat) <dgibson@redhat.com>" # gpg: aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>" # gpg: aka "David Gibson (kernel.org) <dwg@kernel.org>" # Primary key fingerprint: 75F4 6586 AE61 A66C C44E 87DC 6C38 CACA 20D9 B392 * remotes/dgibson/tags/ppc-for-3.1-20180907: target-ppc: Extend HWCAP2 bits for ISA 3.0 target/ppc/kvm: set vcpu as online/offline Fix a deadlock case in the CPU hotplug flow spapr: Correct reference count on spapr-cpu-core mac_newworld: implement custom FWPathProvider uninorth: add ofw-addr property to allow correct fw path generation mac_oldworld: implement custom FWPathProvider grackle: set device fw_name and address for correct fw path generation macio: add addr property to macio IDE object macio: add macio bus to help with fw path generation macio: move MACIOIDEState type declarations to macio.h spapr_pci: fix potential NULL pointer dereference spapr: fix leak of rev array ppc: Remove deprecated ppcemb target Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-08-28qapi: Drop qapi_event_send_FOO()'s Error ** argumentPeter Xu1-4/+4
The generated qapi_event_send_FOO() take an Error ** argument. They can't actually fail, because all they do with the argument is passing it to functions that can't fail: the QObject output visitor, and the @qmp_emit callback, which is either monitor_qapi_event_queue() or event_test_emit(). Drop the argument, and pass &error_abort to the QObject output visitor and @qmp_emit instead. Suggested-by: Eric Blake <eblake@redhat.com> Suggested-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20180815133747.25032-4-peterx@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [Commit message rewritten, update to qapi-code-gen.txt corrected] Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-08-28ppc: Remove deprecated ppcemb targetThomas Huth1-1/+0
There is no known available OS for ppc around anymore that uses page sizes below 4k, so it does not make much sense that we keep wasting our time on building and testing the ppcemb-softmmu target. It has been deprecated since two releases, and nobody complained, so let's remove this now. Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-08-23cpus: allow cpu_get_ticks out of BQLPaolo Bonzini1-15/+20
Because of cpu_ticks_prev, we cannot use a seqlock. But then the conversion is even easier. :) Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-23cpus: protect TimerState writes with a spinlockPaolo Bonzini1-25/+47
In the next patch, we will need to write cpu_ticks_offset from any thread, even outside the BQL. Currently, it is protected by the BQL just because cpu_enable_ticks and cpu_disable_ticks happen to hold it, but the critical sections are well delimited and it's easy to remove the BQL dependency. Add a spinlock that matches vm_clock_seqlock, and hold it when writing to the TimerState. This also lets us fix cpu_update_icount when 64-bit atomics are not available. Fields of TiemrState are reordered to avoid padding. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-23cpus: protect all icount computation with seqlockPaolo Bonzini1-27/+42
Move the icount->ns computation to cpu_get_icount, and make cpu_get_icount_locked return the raw value. This makes the atomic_read__nocheck safe, because it now happens always inside a seqlock and any torn reads will be retried. qemu_icount_bias and icount_time_shift also need to be accessed with atomics. At the same time, however, you don't need atomic_read within the writer, because no concurrent writes are possible. The fix to vmstate lets us keep the struct nicely packed. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-23qom: convert the CPU list to RCUEmilio G. Cota1-1/+1
Iterating over the list without using atomics is undefined behaviour, since the list can be modified concurrently by other threads (e.g. every time a new thread is created in user-mode). Fix it by implementing the CPU list as an RCU QTAILQ. This requires a little bit of extra work to traverse list in reverse order (see previous patch), but other than that the conversion is trivial. Signed-off-by: Emilio G. Cota <cota@braap.org> Message-Id: <20180819091335.22863-12-cota@braap.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-23qsp: track BQL callers explicitlyEmilio G. Cota1-2/+8
The BQL is acquired via qemu_mutex_lock_iothread(), which makes the profiler assign the associated wait time (i.e. most of BQL wait time) entirely to that function. This loses the original call site information, which does not help diagnose BQL contention. Fix it by tracking the callers explicitly. Signed-off-by: Emilio G. Cota <cota@braap.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-22tcg: fix --disable-tcg build breakageEmilio G. Cota1-0/+4
Fix the --disable-tcg breakage introduced by tb_lock's removal by relying on the fact that tcg_enabled() is set to 0 at compile-time under --disable-tcg. While at it, add further asserts to fix builds that enable both --disable-tcg and --enable-debug, which were broken even before tb_lock's removal. Tested to build x86_64-softmmu and i386-softmmu targets. Reported-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Emilio G. Cota <cota@braap.org> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-22qapi: remove empty flat union branches and typesAnton Nefedov1-2/+0
Flat unions may now have uncovered branches, so it is possible to get rid of empty types defined for that purpose only. Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1529311206-76847-3-git-send-email-anton.nefedov@virtuozzo.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-05-09cpus: tcg: fix never exiting loop on unplugCédric Le Goater1-1/+1
Commit 9b0605f9837b ("cpus: tcg: unregister thread with RCU, fix exiting of loop on unplug") changed the exit condition of the loop in the vCPU thread function but forgot to remove the beginning 'while (1)' statement. The resulting code : while (1) { ... } while (!cpu->unplug || cpu_can_run(cpu)); is a sequence of two distinct two while() loops, the first not exiting in case of an unplug event. Remove the first while (1) to fix CPU unplug. Signed-off-by: Cédric Le Goater <clg@kaod.org> Message-Id: <20180425131828.15604-1-clg@kaod.org> Cc: qemu-stable@nongnu.org Fixes: 9b0605f9837b68fd56c7fc7c96a3a1a3b983687d Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Cédric Le Goater <clg@kaod.org>
2018-05-09cpus: Fix event order on resume of stopped guestMarkus Armbruster1-8/+8
When resume of a stopped guest immediately runs into block device errors, the BLOCK_IO_ERROR event is sent before the RESUME event. Reproducer: 1. Create a scratch image $ dd if=/dev/zero of=scratch.img bs=1M count=100 Size doesn't actually matter. 2. Prepare blkdebug configuration: $ cat >blkdebug.conf <<EOF [inject-error] event = "write_aio" errno = "5" EOF Note that errno 5 is EIO. 3. Run a guest with an additional scratch disk, i.e. with additional arguments -drive if=none,id=scratch-drive,format=raw,werror=stop,file=blkdebug:blkdebug.conf:scratch.img -device virtio-blk-pci,id=scratch,drive=scratch-drive The blkdebug part makes all writes to the scratch drive fail with EIO. The werror=stop pauses the guest on write errors. 4. Connect to the QMP socket e.g. like this: $ socat UNIX:/your/qmp/socket READLINE,history=$HOME/.qmp_history,prompt='QMP> ' Issue QMP command 'qmp_capabilities': QMP> { "execute": "qmp_capabilities" } 5. Boot the guest. 6. In the guest, write to the scratch disk, e.g. like this: # dd if=/dev/zero of=/dev/vdb count=1 Do double-check the device specified with of= is actually the scratch device! 7. Issue QMP command 'cont': QMP> { "execute": "cont" } After step 6, I get a BLOCK_IO_ERROR event followed by a STOP event. Good. After step 7, I get BLOCK_IO_ERROR, then RESUME, then STOP. Not so good; I'd expect RESUME, then BLOCK_IO_ERROR, then STOP. The funny event order confuses libvirt: virsh -r domstate DOMAIN --reason reports "paused (unknown)" rather than "paused (I/O error)". The culprit is vm_prepare_start(). /* Ensure that a STOP/RESUME pair of events is emitted if a * vmstop request was pending. The BLOCK_IO_ERROR event, for * example, according to documentation is always followed by * the STOP event. */ if (runstate_is_running()) { qapi_event_send_stop(&error_abort); res = -1; } else { replay_enable_events(); cpu_enable_ticks(); runstate_set(RUN_STATE_RUNNING); vm_state_notify(1, RUN_STATE_RUNNING); } /* We are sending this now, but the CPUs will be resumed shortly later */ qapi_event_send_resume(&error_abort); return res; When resuming a stopped guest, we take the else branch before we get to sending RESUME. vm_state_notify() runs virtio_vmstate_change(), among other things. This restarts I/O, triggering the BLOCK_IO_ERROR event. Reshuffle vm_prepare_start() to send the RESUME event earlier. Fixes RHBZ 1566153. Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180423084518.2426-1-armbru@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-04qapi: discriminate CpuInfoFast on SysEmuTarget, not CpuInfoArchLaszlo Ersek1-24/+63
Add a new field @target (of type @SysEmuTarget) to the output of the @query-cpus-fast command, which provides more information about the emulation target than the field @arch (of type @CpuInfoArch). Make @target the new discriminator for the @CpuInfoFast return structure. Keep @arch for compatibility. Cc: "Daniel P. Berrange" <berrange@redhat.com> Cc: Eric Blake <eblake@redhat.com> Cc: Markus Armbruster <armbru@redhat.com> Signed-off-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20180427192852.15013-5-lersek@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-05-04qapi: fill in CpuInfoFast.arch in query-cpus-fastLaszlo Ersek1-1/+15
* Commit ca230ff33f89 added the @arch field to @CpuInfoFast, but it failed to set the new field in qmp_query_cpus_fast(), when TARGET_S390X was not defined. The updated @query-cpus-fast example in "qapi-schema.json" showed "arch":"x86" only because qmp_query_cpus_fast() calls g_malloc0() to allocate @CpuInfoFast, and the CPU_INFO_ARCH_X86 enum constant is generated with value 0. All @arch values other than @s390 implied the @CpuInfoOther sub-struct for @CpuInfoFast -- at the time of writing the patch --, thus no fields other than @arch needed to be set when TARGET_S390X was not defined. Set @arch now, by copying the corresponding assignments from qmp_query_cpus(). * Commit 25fa194b7b11 added the @riscv enum constant to @CpuInfoArch (used in both @CpuInfo and @CpuInfoFast -- the return types of the @query-cpus and @query-cpus-fast commands, respectively), and assigned, in both return structures, the @CpuInfoRISCV sub-structure to the new enum value. However, qmp_query_cpus_fast() would not populate either the @arch field or the @CpuInfoRISCV sub-structure, when TARGET_RISCV was defined; only qmp_query_cpus() would. Assign @CpuInfoOther to the @riscv enum constant in @CpuInfoFast, and populate only the @arch field in qmp_query_cpus_fast(). Getting CPU state without interrupting KVM is an exceptional thing that only S390X does currently. Quoting Cornelia Huck <cohuck@redhat.com>, "s390x is exceptional in that it has state in QEMU that is actually interesting for upper layers and can be retrieved without performance penalty". See also <https://www.redhat.com/archives/libvir-list/2018-February/msg00121.html>. Cc: Cornelia Huck <cohuck@redhat.com> Cc: Eric Blake <eblake@redhat.com> Cc: Markus Armbruster <armbru@redhat.com> Cc: Viktor VM Mihajlovski <mihajlov@linux.vnet.ibm.com> Cc: qemu-stable@nongnu.org Fixes: ca230ff33f89bf7102cbfbc2328716da6750aaed Fixes: 25fa194b7b11901561532e435beb83d046899f7a Signed-off-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180427192852.15013-2-lersek@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-04-10cpus.c: ensure running CPU recalculates icount deadlines on timer expiryPeter Maydell1-1/+9
When we run in TCG icount mode, we calculate the number of instructions to execute using tcg_get_icount_limit(), which ensures that we stop execution at the next timer deadline. However there is a bug where currently we do not recalculate that limit if the guest reprograms a timer so that the next deadline moves closer, and so we will continue execution until the original limit and fire the timer later than we should. Fix this bug in qemu_timer_notify_cb(): if we are currently running a VCPU in icount mode, we simply need to kick it out of the main loop and back to tcg_cpu_exec(), where it will recalculate the icount limit. If we are not currently running a VCPU, then we retain the existing logic for waking up a halted CPU. Cc: qemu-stable@nongnu.org Fixes: https://bugs.launchpad.net/qemu/+bug/1754038 Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Message-id: 20180406123838.21249-1-peter.maydell@linaro.org
2018-03-12replay: push replay_mutex_lock up the call treeAlex Bennée1-2/+22
Now instead of using the replay_lock to guard the output of the log we now use it to protect the whole execution section. This replaces what the BQL used to do when it was held during TCG execution. We also introduce some rules for locking order - mainly that you cannot take the replay_mutex while holding the BQL. This leads to some slight sophistry during start-up and extending the replay_mutex_destroy function to unlock the mutex without checking for the BQL condition so it can be cleanly dropped in the non-replay case. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru> Tested-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru> Message-Id: <20180227095248.1060.40374.stgit@pasha-VirtualBox> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2018-03-09Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into ↵Peter Maydell1-3/+13
staging # gpg: Signature made Fri 09 Mar 2018 13:19:02 GMT # gpg: using RSA key 9CA4ABB381AB73C8 # gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" # gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>" # Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35 775A 9CA4 ABB3 81AB 73C8 * remotes/stefanha/tags/block-pull-request: vl: introduce vm_shutdown() virtio-scsi: fix race between .ioeventfd_stop() and vq handler virtio-blk: fix race between .ioeventfd_stop() and vq handler block: add aio_wait_bh_oneshot() virtio-blk: dataplane: Don't batch notifications if EVENT_IDX is present README: Fix typo 'git-publish' block: Fix qemu crash when using scsi-block Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-03-08vl: introduce vm_shutdown()Stefan Hajnoczi1-3/+13
Commit 00d09fdbbae5f7864ce754913efc84c12fdf9f1a ("vl: pause vcpus before stopping iothreads") and commit dce8921b2baaf95974af8176406881872067adfa ("iothread: Stop threads before main() quits") tried to work around the fact that emulation was still active during termination by stopping iothreads. They suffer from race conditions: 1. virtio_scsi_handle_cmd_vq() racing with iothread_stop_all() hits the virtio_scsi_ctx_check() assertion failure because the BDS AioContext has been modified by iothread_stop_all(). 2. Guest vq kick racing with main loop termination leaves a readable ioeventfd that is handled by the next aio_poll() when external clients are enabled again, resulting in unwanted emulation activity. This patch obsoletes those commits by fully disabling emulation activity when vcpus are stopped. Use the new vm_shutdown() function instead of pause_all_vcpus() so that vm change state handlers are invoked too. Virtio devices will now stop their ioeventfds, preventing further emulation activity after vm_stop(). Note that vm_stop(RUN_STATE_SHUTDOWN) cannot be used because it emits a QMP STOP event that may affect existing clients. It is no longer necessary to call replay_disable_events() directly since vm_shutdown() does so already. Drop iothread_stop_all() since it is no longer used. Cc: Fam Zheng <famz@redhat.com> Cc: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 20180307144205.20619-5-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-03-07RISC-V Build InfrastructureMichael Clark1-0/+6
This adds RISC-V into the build system enabling the following targets: - riscv32-softmmu - riscv64-softmmu - riscv32-linux-user - riscv64-linux-user This adds defaults configs for RISC-V, enables the build for the RISC-V CPU core, hardware, and Linux User Emulation. The 'qemu-binfmt-conf.sh' script is updated to add the RISC-V ELF magic. Expected checkpatch errors for consistency reasons: ERROR: line over 90 characters FILE: scripts/qemu-binfmt-conf.sh Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-06cpus: CPU threads are always created initially for one CPU onlyDavid Hildenbrand1-5/+3
It can never happen for single-threaded TCG that we have more than one CPU in the list, while the first one has not been marked as "created". Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20180209195239.16048-4-david@redhat.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-06cpus: wait for CPU creation at central placeDavid Hildenbrand1-18/+4
We can now also wait for the CPU creation for single-threaded TCG, so we can move the waiting bits further out. Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20180209195239.16048-3-david@redhat.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-06cpus: properly inititalize CPU > 1 under single-threaded TCGDavid Hildenbrand1-0/+3
All but the first CPU are currently not fully inititalized (e.g. cpu->created is never set). Signed-off-by: David Hildenbrand <david@redhat.com> Message-Id: <20180209195239.16048-2-david@redhat.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-02qapi: Empty out qapi-schema.jsonMarkus Armbruster1-1/+1
The previous commit improved compile time by including less of the generated QAPI headers. This is impossible for stuff defined directly in qapi-schema.json, because that ends up in headers that that pull in everything. Move everything but include directives from qapi-schema.json to new sub-module qapi/misc.json, then include just the "misc" shard where possible. It's possible everywhere, except: * monitor.c needs qmp-command.h to get qmp_init_marshal() * monitor.c, ui/vnc.c and the generated qapi-event-FOO.c need qapi-event.h to get enum QAPIEvent Perhaps we'll get rid of those some other day. Adding a type to qapi/migration.json now recompiles some 120 instead of 2300 out of 5100 objects. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180211093607.27351-25-armbru@redhat.com> [eblake: rebase to master] Signed-off-by: Eric Blake <eblake@redhat.com>
2018-03-02Include less of the generated modular QAPI headersMarkus Armbruster1-1/+1
In my "build everything" tree, a change to the types in qapi-schema.json triggers a recompile of about 4800 out of 5100 objects. The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h, qapi-types.h. Each of these headers still includes all its shards. Reduce compile time by including just the shards we actually need. To illustrate the benefits: adding a type to qapi/migration.json now recompiles some 2300 instead of 4800 objects. The next commit will improve it further. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180211093607.27351-24-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> [eblake: rebase to master] Signed-off-by: Eric Blake <eblake@redhat.com>
2018-02-26qmp: add architecture specific cpu data for query-cpus-fastViktor Mihajlovski1-0/+10
The s390 CPU state can be retrieved without interrupting the VM execution. Extendend the CpuInfoFast union with architecture specific data and an implementation for s390. Return data looks like this: [ {"thread-id":64301,"props":{"core-id":0}, "arch":"s390","cpu-state":"operating", "qom-path":"/machine/unattached/device[0]","cpu-index":0}, {"thread-id":64302,"props":{"core-id":1}, "arch":"s390","cpu-state":"operating", "qom-path":"/machine/unattached/device[1]","cpu-index":1} ] Signed-off-by: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <1518797321-28356-4-git-send-email-mihajlov@linux.vnet.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-02-26qmp: add query-cpus-fastLuiz Capitulino1-0/+38
The query-cpus command has an extremely serious side effect: it always interrupts all running vCPUs so that they can run ioctl calls. This can cause a huge performance degradation for some workloads. And most of the information retrieved by the ioctl calls are not even used by query-cpus. This commit introduces a replacement for query-cpus called query-cpus-fast, which has the following features: o Never interrupt vCPUs threads. query-cpus-fast only returns vCPU information maintained by QEMU itself, which should be sufficient for most management software needs o Drop "halted" field as it can not be retrieved in a fast way on most architectures o Drop irrelevant fields such as "current", "pc" and "arch" o Rename some fields for better clarification & proper naming standard Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com> Signed-off-by: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com> Message-Id: <1518797321-28356-3-git-send-email-mihajlov@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>