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2017-03-14icount: process QEMU_CLOCK_VIRTUAL timers in vCPU threadPaolo Bonzini
icount has become much slower after tcg_cpu_exec has stopped using the BQL. There is also a latent bug that is masked by the slowness. The slowness happens because every occurrence of a QEMU_CLOCK_VIRTUAL timer now has to wake up the I/O thread and wait for it. The rendez-vous is mediated by the BQL QemuMutex: - handle_icount_deadline wakes up the I/O thread with BQL taken - the I/O thread wakes up and waits on the BQL - the VCPU thread releases the BQL a little later - the I/O thread raises an interrupt, which calls qemu_cpu_kick - the VCPU thread notices the interrupt, takes the BQL to process it and waits on it All this back and forth is extremely expensive, causing a 6 to 8-fold slowdown when icount is turned on. One may think that the issue is that the VCPU thread is too dependent on the BQL, but then the latent bug comes in. I first tried removing the BQL completely from the x86 cpu_exec, only to see everything break. The only way to fix it (and make everything slow again) was to add a dummy BQL lock/unlock pair. This is because in -icount mode you really have to process the events before the CPU restarts executing the next instruction. Therefore, this series moves the processing of QEMU_CLOCK_VIRTUAL timers straight in the vCPU thread when running in icount mode. The required changes include: - make the timer notification callback wake up TCG's single vCPU thread when run from another thread. By using async_run_on_cpu, the callback can override all_cpu_threads_idle() when the CPU is halted. - move handle_icount_deadline after qemu_tcg_wait_io_event, so that the timer notification callback is invoked after the dummy work item wakes up the vCPU thread - make handle_icount_deadline run the timers instead of just waking the I/O thread. - stop processing the timers in the main loop Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-14cpus: define QEMUTimerListNotifyCB for QEMU system emulationPaolo Bonzini
There is no change for now, because the callback just invokes qemu_notify_event. Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-09cpus.c: add additional error_report when !TARGET_SUPPORT_MTTCGAlex Bennée
While we may fail the memory ordering check later that can be confusing. So in cases where TARGET_SUPPORT_MTTCG has yet to be defined we should say so specifically. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-03-09vl/cpus: be smarter with icount and MTTCGAlex Bennée
The sense of the test was inverted. Make it simple, if icount is enabled then we disabled MTTCG by default. If the user tries to force MTTCG upon us then we tell them "no". Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net>
2017-03-03KVM: move SIG_IPI handling to kvm-all.cPaolo Bonzini
This lets us remove a bunch of CONFIG_LINUX defines. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-03KVM: do not use sigtimedwait to catch SIGBUSPaolo Bonzini
Call kvm_on_sigbus_vcpu asynchronously from the VCPU thread. Information for the SIGBUS can be stored in thread-local variables and processed later in kvm_cpu_exec. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-03cpus: reorganize signal handling codePaolo Bonzini
Move the KVM "eat signals" code under CONFIG_LINUX, in preparation for moving it to kvm-all.c; reraise non-MCE SIGBUS immediately, without passing it to KVM. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-03cpus: remove ugly cast on sigbus_handlerPaolo Bonzini
The cast is there because sigbus_handler is invoked via sigfd_handler. But it feels just wrong to use struct qemu_signalfd_siginfo in the prototype of a function that is passed to sigaction. Instead, do a simple-minded conversion of qemu_signalfd_siginfo to siginfo_t. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-24tcg: handle EXCP_ATOMIC exception for system emulationPranith Kumar
The patch enables handling atomic code in the guest. This should be preferably done in cpu_handle_exception(), but the current assumptions regarding when we can execute atomic sections cause a deadlock. The current mechanism discards the flags which were set in atomic execution. We ensure they are properly saved by calling the cc->cpu_exec_enter/leave() functions around the loop. As we are running cpu_exec_step_atomic() from the outermost loop we need to avoid an abort() when single stepping over atomic code since debug exception longjmp will point to the the setlongjmp in cpu_exec(). We do this by setting a new jmp_env so that it jumps back here on an exception. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> [AJB: tweak title, merge with new patches, add mmap_lock] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> CC: Paolo Bonzini <pbonzini@redhat.com>
2017-02-24tcg: enable thread-per-vCPUAlex Bennée
There are a couple of changes that occur at the same time here: - introduce a single vCPU qemu_tcg_cpu_thread_fn One of these is spawned per vCPU with its own Thread and Condition variables. qemu_tcg_rr_cpu_thread_fn is the new name for the old single threaded function. - the TLS current_cpu variable is now live for the lifetime of MTTCG vCPU threads. This is for future work where async jobs need to know the vCPU context they are operating in. The user to switch on multi-thread behaviour and spawn a thread per-vCPU. For a simple test kvm-unit-test like: ./arm/run ./arm/locking-test.flat -smp 4 -accel tcg,thread=multi Will now use 4 vCPU threads and have an expected FAIL (instead of the unexpected PASS) as the default mode of the test has no protection when incrementing a shared variable. We enable the parallel_cpus flag to ensure we generate correct barrier and atomic code if supported by the front and backends. This doesn't automatically enable MTTCG until default_mttcg_enabled() is updated to check the configuration is supported. Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [AJB: Some fixes, conditionally, commit rewording] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net>
2017-02-24tcg: remove global exit_requestAlex Bennée
There are now only two uses of the global exit_request left. The first ensures we exit the run_loop when we first start to process pending work and in the kick handler. This is just as easily done by setting the first_cpu->exit_request flag. The second use is in the round robin kick routine. The global exit_request ensured every vCPU would set its local exit_request and cause a full exit of the loop. Now the iothread isn't being held while running we can just rely on the kick handler to push us out as intended. We lightly re-factor the main vCPU thread to ensure cpu->exit_requests cause us to exit the main loop and process any IO requests that might come along. As an cpu->exit_request may legitimately get squashed while processing the EXCP_INTERRUPT exception we also check cpu->queued_work_first to ensure queued work is expedited as soon as possible. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net>
2017-02-24tcg: drop global lock during TCG code executionJan Kiszka
This finally allows TCG to benefit from the iothread introduction: Drop the global mutex while running pure TCG CPU code. Reacquire the lock when entering MMIO or PIO emulation, or when leaving the TCG loop. We have to revert a few optimization for the current TCG threading model, namely kicking the TCG thread in qemu_mutex_lock_iothread and not kicking it in qemu_cpu_kick. We also need to disable RAM block reordering until we have a more efficient locking mechanism at hand. Still, a Linux x86 UP guest and my Musicpal ARM model boot fine here. These numbers demonstrate where we gain something: 20338 jan 20 0 331m 75m 6904 R 99 0.9 0:50.95 qemu-system-arm 20337 jan 20 0 331m 75m 6904 S 20 0.9 0:26.50 qemu-system-arm The guest CPU was fully loaded, but the iothread could still run mostly independent on a second core. Without the patch we don't get beyond 32206 jan 20 0 330m 73m 7036 R 82 0.9 1:06.00 qemu-system-arm 32204 jan 20 0 330m 73m 7036 S 21 0.9 0:17.03 qemu-system-arm We don't benefit significantly, though, when the guest is not fully loading a host CPU. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Message-Id: <1439220437-23957-10-git-send-email-fred.konrad@greensocs.com> [FK: Rebase, fix qemu_devices_reset deadlock, rm address_space_* mutex] Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com> [EGC: fixed iothread lock for cpu-exec IRQ handling] Signed-off-by: Emilio G. Cota <cota@braap.org> [AJB: -smp single-threaded fix, clean commit msg, BQL fixes] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com> [PM: target-arm changes] Acked-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-24tcg: rename tcg_current_cpu to tcg_current_rr_cpuAlex Bennée
..and make the definition local to cpus. In preparation for MTTCG the concept of a global tcg_current_cpu will no longer make sense. However we still need to keep track of it in the single-threaded case to be able to exit quickly when required. qemu_cpu_kick_no_halt() moves and becomes qemu_cpu_kick_rr_cpu() to emphasise its use-case. qemu_cpu_kick now kicks the relevant cpu as well as qemu_kick_rr_cpu() which will become a no-op in MTTCG. For the time being the setting of the global exit_request remains. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2017-02-24tcg: add kick timer for single-threaded vCPU emulationAlex Bennée
Currently we rely on the side effect of the main loop grabbing the iothread_mutex to give any long running basic block chains a kick to ensure the next vCPU is scheduled. As this code is being re-factored and rationalised we now do it explicitly here. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
2017-02-24tcg: add options for enabling MTTCGKONRAD Frederic
We know there will be cases where MTTCG won't work until additional work is done in the front/back ends to support. It will however be useful to be able to turn it on. As a result MTTCG will default to off unless the combination is supported. However the user can turn it on for the sake of testing. Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com> [AJB: move to -accel tcg,thread=multi|single, defaults] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net>
2017-02-16move vm_start to cpus.cClaudio Imbrenda
This patch: * moves vm_start to cpus.c. * exports qemu_vmstop_requested, since it's needed by vm_start. * extracts vm_prepare_start from vm_start; it does what vm_start did, except restarting the cpus. * vm_start now calls vm_prepare_start and then restarts the cpus. Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com> Message-Id: <1487092068-16562-2-git-send-email-imbrenda@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-01-19Plumb the HAXM-based hardware acceleration supportVincent Palatin
Use the Intel HAX is kernel-based hardware acceleration module for Windows (similar to KVM on Linux). Based on the "target/i386: Add Intel HAX to android emulator" patch from David Chou <david.j.chou@intel.com> Signed-off-by: Vincent Palatin <vpalatin@chromium.org> Message-Id: <7b9cae28a0c379ab459c7a8545c9a39762bd394f.1484045952.git.vpalatin@chromium.org> [Drop hax_populate_ram stub. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-01-19kvm: move cpu synchronization codeVincent Palatin
Move the generic cpu_synchronize_ functions to the common hw_accel.h header, in order to prepare for the addition of a second hardware accelerator. Signed-off-by: Stefan Weil <sw@weilnetz.de> Signed-off-by: Vincent Palatin <vpalatin@chromium.org> Message-Id: <f5c3cffe8d520011df1c2e5437bb814989b48332.1484045952.git.vpalatin@chromium.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-31*_run_on_cpu: introduce run_on_cpu_data typePaolo Bonzini
This changes the *_run_on_cpu APIs (and helpers) to pass data in a run_on_cpu_data type instead of a plain void *. This is because we sometimes want to pass a target address (target_ulong) and this fails on 32 bit hosts emulating 64 bit guests. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20161027151030.20863-24-alex.bennee@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-31cpus: re-factor out handle_icount_deadlineAlex Bennée
In preparation for adding a MTTCG thread we re-factor out a bit of what will be common code to handle the QEMU_CLOCK_VIRTUAL expiration. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Message-Id: <20161027151030.20863-18-alex.bennee@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-31tcg: cpus rm tcg_exec_all()Alex Bennée
In preparation for multi-threaded TCG we remove tcg_exec_all and move all the CPU cycling into the main thread function. When MTTCG is enabled we shall use a separate thread function which only handles one vCPU. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Message-Id: <20161027151030.20863-13-alex.bennee@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-31tcg: move tcg_exec_all and helpers above thread fnAlex Bennée
This is a pure mechanical change in preparation for up-coming re-factoring. Instead of a forward declaration for tcg_exec_all it and the associated helper functions are moved in front of the call from qemu_tcg_cpu_thread_fn. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Message-Id: <20161027151030.20863-12-alex.bennee@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-31cpus: make all_vcpus_paused() return boolAlex Bennée
Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Message-Id: <20161027151030.20863-2-alex.bennee@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-26tcg: Add EXCP_ATOMICRichard Henderson
When we cannot emulate an atomic operation within a parallel context, this exception allows us to stop the world and try again in a serial context. Reviewed-by: Emilio G. Cota <cota@braap.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-29qemu: use bdrv_flush_all for vm_stop et alJohn Snow
Reimplement bdrv_flush_all for vm_stop. In contrast to blk_flush_all, bdrv_flush_all does not have device model restrictions. This allows us to flush and halt unconditionally without error. This allows us to do things like migrate when we have a device with an open tray, but has a node that may need to be flushed, or nodes that aren't currently attached to any device and need to be flushed. Specifically, this allows us to migrate when we have a CDROM with an open tray. Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-27replay: allow replay stopping and restartingPavel Dovgalyuk
This patch fixes bug with stopping and restarting replay through monitor. Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru> Message-Id: <20160926080815.6992.71818.stgit@PASHA-ISP> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-27cpus-common: move exclusive work infrastructure from linux-userPaolo Bonzini
This will serve as the base for async_safe_run_on_cpu. Because start_exclusive uses CPU_FOREACH, merge exclusive_lock with qemu_cpu_list_lock: together with a call to exclusive_idle (via cpu_exec_start/end) in cpu_list_add, this protects exclusive work against concurrent CPU addition and removal. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-27cpus-common: move CPU work item management to common codeSergey Fedorov
Make CPU work core functions common between system and user-mode emulation. User-mode does not use run_on_cpu, so do not implement it. Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com> Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <1470158864-17651-10-git-send-email-alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-27cpus: Rename flush_queued_work()Sergey Fedorov
To avoid possible confusion, rename flush_queued_work() to process_queued_cpu_work(). Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com> Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <1470158864-17651-6-git-send-email-alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-27cpus: Move common code out of {async_, }run_on_cpu()Sergey Fedorov
Move the code common between run_on_cpu() and async_run_on_cpu() into a new function queue_work_on_cpu(). Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com> Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <1470158864-17651-4-git-send-email-alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-27cpus: pass CPUState to run_on_cpu helpersAlex Bennée
CPUState is a fairly common pointer to pass to these helpers. This means if you need other arguments for the async_run_on_cpu case you end up having to do a g_malloc to stuff additional data into the routine. For the current users this isn't a massive deal but for MTTCG this gets cumbersome when the only other parameter is often an address. This adds the typedef run_on_cpu_func for helper functions which has an explicit CPUState * passed as the first parameter. All the users of run_on_cpu and async_run_on_cpu have had their helpers updated to use CPUState where available. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> [Sergey Fedorov: - eliminate more CPUState in user data; - remove unnecessary user data passing; - fix target-s390x/kvm.c and target-s390x/misc_helper.c] Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org> Acked-by: David Gibson <david@gibson.dropbear.id.au> (ppc parts) Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> (s390 parts) Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <1470158864-17651-3-git-send-email-alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-15Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into stagingPeter Maydell
* minor patches here and there * MTTCG: lock-free TB lookup * SCSI: bugfixes for MPTSAS, MegaSAS, LSI53c, vmw_pvscsi * buffer_is_zero rewrite (except for one patch) * chardev: qemu_chr_fe_write checks * checkpatch improvement for markdown preformatted text * default-configs cleanups * atomics cleanups # gpg: Signature made Tue 13 Sep 2016 18:14:30 BST # gpg: using RSA key 0xBFFBD25F78C7AE83 # 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: (58 commits) cutils: Add generic prefetch cutils: Add SSE4 version cutils: Add test for buffer_is_zero cutils: Remove ppc buffer zero checking cutils: Remove aarch64 buffer zero checking cutils: Rearrange buffer_is_zero acceleration cutils: Export only buffer_is_zero cutils: Remove SPLAT macro cutils: Move buffer_is_zero and subroutines to a new file ppc: do not redefine CPUPPCState x86/lapic: Load LAPIC state at post_load optionrom: do not rely on compiler's bswap optimization checkpatch: Fix whitespace checks for documentation code blocks atomics: Use __atomic_*_n() variant primitives atomics: Remove redundant barrier()'s kvm-all: drop kvm_setup_guest_memory i8257: Make device "i8257" unavailable with -device Revert "megasas: remove useless check for cmd->frame" char: convert qemu_chr_fe_write to qemu_chr_fe_write_all hw: replace most use of qemu_chr_fe_write with qemu_chr_fe_write_all ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Conflicts: cpus.c tests/Makefile.include
2016-09-13cpus: update commentsCao jin
The returned value of cpu_get_clock() is plused with the offset, so it is the time elapsed in virtual machine when vm is active. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc Peter Crosthwaite <crosthwaite.peter@gmail.com> Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com> Message-Id: <1469790338-28990-4-git-send-email-caoj.fnst@cn.fujitsu.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13cpus: rename local variable to meaningful oneCao jin
The function actually returns monotonic time value in nanosecond, the "ticks" is not suitable. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc Peter Crosthwaite <crosthwaite.peter@gmail.com> Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com> Message-Id: <1469790338-28990-3-git-send-email-caoj.fnst@cn.fujitsu.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13timer/cpus: fix some typos and update some commentsCao jin
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-06-11seqlock: rename write_lock/unlock to write_begin/endEmilio G. Cota
It is a more appropriate name, now that the mutex embedded in the seqlock is gone. Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Emilio G. Cota <cota@braap.org> Message-Id: <1465412133-3029-4-git-send-email-cota@braap.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-06-11seqlock: remove optional mutexEmilio G. Cota
This option is unused; besides, it bloats the struct when not needed. Let's just let writers define their own locks elsewhere. Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Emilio G. Cota <cota@braap.org> Message-Id: <1465412133-3029-3-git-send-email-cota@braap.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-05-30cpu: Add a sync version of cpu_remove()Bharata B Rao
This sync API will be used by the CPU hotplug code to wait for the CPU to completely get removed before flagging the failure to the device_add command. Sync version of this call is needed to correctly recover from CPU realization failures when ->plug() handler fails. Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-30cpu: Reclaim vCPU objectsGu Zheng
In order to deal well with the kvm vcpus (which can not be removed without any protection), we do not close KVM vcpu fd, just record and mark it as stopped into a list, so that we can reuse it for the appending cpu hot-add request if possible. It is also the approach that kvm guys suggested: https://www.mail-archive.com/kvm@vger.kernel.org/msg102839.html Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com> Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com> Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com> [- Explicit CPU_REMOVE() from qemu_kvm/tcg_destroy_vcpu() isn't needed as it is done from cpu_exec_exit() - Use iothread mutex instead of global mutex during destroy - Don't cleanup vCPU object from vCPU thread context but leave it to the callers (device_add/device_del)] Reviewed-by: Thomas Huth <thuth@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-23cpus: call the core nmi injection functionBandan Das
We can call the common function here directly since x86 specific actions will be taken care of by the arch specific nmi handler Signed-off-by: Bandan Das <bsd@redhat.com> Message-Id: <1463761717-26558-4-git-send-email-bsd@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-23cpus.c: Use pthread_sigmask() rather than sigprocmask()Peter Maydell
On Linux, sigprocmask() and pthread_sigmask() are in practice the same thing (they only set the signal mask for the calling thread), but the documentation states that the behaviour of sigprocmask() in a multithreaded process is undefined. Use pthread_sigmask() instead (which is what we do in almost all places in QEMU that alter the signal mask already). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-Id: <1463420039-29761-1-git-send-email-peter.maydell@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19cpu: move exec-all.h inclusion out of cpu.hPaolo Bonzini
exec-all.h contains TCG-specific definitions. It is not needed outside TCG-specific files such as translate.c, exec.c or *helper.c. One generic function had snuck into include/exec/exec-all.h; move it to include/qom/cpu.h. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19qemu-common: push cpu.h inclusion out of qemu-common.hPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-04-05cpus: don't use atomic_read for vm_clock_warp_startAlex Bennée
As vm_clock_warp_start is a 64 bit value this causes problems for the compiler trying to come up with a suitable atomic operation on 32 bit hosts. Because the variable is protected by vm_clock_seqlock, we check its value inside a seqlock critical section. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <1459780549-12942-2-git-send-email-alex.bennee@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22Replaced get_tick_per_sec() by NANOSECONDS_PER_SECONDRutuja Shah
This patch replaces get_ticks_per_sec() calls with the macro NANOSECONDS_PER_SECOND. Also, as there are no callers, get_ticks_per_sec() is then removed. This replacement improves the readability and understandability of code. For example, timer_mod(fdctrl->result_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + (get_ticks_per_sec() / 50)); NANOSECONDS_PER_SECOND makes it obvious that qemu_clock_get_ns matches the unit of the expression on the right side of the plus. Signed-off-by: Rutuja Shah <rutu.shah.26@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-17block: Use blk_{commit,flush}_all() consistentlyMax Reitz
Replace bdrv_commmit_all() and bdrv_flush_all() by their BlockBackend equivalents. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-15icount: decouple warp callsPavel Dovgalyuk
qemu_clock_warp function is called to update virtual clock when CPU is sleeping. This function includes replay checkpoint to make execution deterministic in icount mode. Record/replay module flushes async event queue at checkpoints. Some of the events (e.g., block devices operations) include interaction with hardware. E.g., APIC polled by block devices sets one of IRQ flags. Flag to be set depends on currently executed thread (CPU or iothread). Therefore in replay mode we have to process the checkpoints in the same thread as they were recorded. qemu_clock_warp function (and its checkpoint) may be called from different thread. This patch decouples two different execution cases of this function: call when CPU is sleeping from iothread and call from cpu thread to update virtual clock. First task is performed by qemu_start_warp_timer function. It sets warp timer event to the moment of nearest pending virtual timer. Second function (qemu_account_warp_timer) is called from cpu thread before execution of the code. It advances virtual clock by adding the length of period while CPU was sleeping. Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru> Message-Id: <20160310115609.4812.44986.stgit@PASHA-ISP> [Update docs. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-15icount: remove obsolete warp callPavel Dovgalyuk
qemu_clock_warp call in qemu_tcg_wait_io_event function is not needed anymore, because it is called in every iteration of main_loop_wait. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru> Message-Id: <20160310115603.4812.67559.stgit@PASHA-ISP> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-07icount: possible options for sleep are on or offPranith Kumar
icount sleep takes on or off as options. A few places mention sleep=no which is not accepted. This patch corrects them. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Message-Id: <1456499811-16819-1-git-send-email-bobby.prani@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-19qapi: Don't box branches of flat unionsEric Blake
There's no reason to do two malloc's for a flat union; let's just inline the branch struct directly into the C union branch of the flat union. Surprisingly, fewer clients were actually using explicit references to the branch types in comparison to the number of flat unions thus modified. This lets us reduce the hack in qapi-types:gen_variants() added in the previous patch; we no longer need to distinguish between alternates and flat unions. The change to unboxed structs means that u.data (added in commit cee2dedb) is now coincident with random fields of each branch of the flat union, whereas beforehand it was only coincident with pointers (since all branches of a flat union have to be objects). Note that this was already the case for simple unions - but there we got lucky. Remember, visit_start_union() blindly returns true for all visitors except for the dealloc visitor, where it returns the value !!obj->u.data, and that this result then controls whether to proceed with the visit to the variant. Pre-patch, this meant that flat unions were testing whether the boxed pointer was still NULL, and thereby skipping visit_end_implicit_struct() and avoiding a NULL dereference if the pointer had not been allocated. The same was true for simple unions where the current branch had pointer type, except there we bypassed visit_type_FOO(). But for simple unions where the current branch had scalar type, the contents of that scalar meant that the decision to call visit_type_FOO() was data-dependent - the reason we got lucky there is that visit_type_FOO() for all scalar types in the dealloc visitor is a no-op (only the pointer variants had anything to free), so it did not matter whether the dealloc visit was skipped. But with this patch, we would risk leaking memory if we could skip a call to visit_type_FOO_fields() based solely on a data-dependent decision. But notice: in the dealloc visitor, visit_type_FOO() already handles a NULL obj - it was only the visit_type_implicit_FOO() that was failing to check for NULL. And now that we have refactored things to have the branch be part of the parent struct, we no longer have a separate pointer that can be NULL in the first place. So we can just delete the call to visit_start_union() altogether, and blindly visit the branch type; there is no change in behavior except to the dealloc visitor, where we now unconditionally visit the branch, but where that visit is now always safe (for a flat union, we can no longer dereference NULL, and for a simple union, visit_type_FOO() was already safely handling NULL on pointer types). Unfortunately, simple unions are not as easy to switch to unboxed layout; because we are special-casing the hidden implicit type with a single 'data' member, we really DO need to keep calling another layer of visit_start_struct(), with a second malloc; although there are some cleanups planned for simple unions in later patches. visit_start_union() and gen_visit_implicit_struct() are now unused. Drop them. Note that after this patch, the only remaining use of visit_start_implicit_struct() is for alternate types; the next patch will do further cleanup based on that fact. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1455778109-6278-14-git-send-email-eblake@redhat.com> [Dead code deletion squashed in, commit message updated accordingly] Signed-off-by: Markus Armbruster <armbru@redhat.com>
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