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2011-09-02main: force enabling of I/O threadAnthony Liguori
Enabling the I/O thread by default seems like an important part of declaring 1.0. Besides allowing true SMP support with KVM, the I/O thread means that the TCG VCPU doesn't have to multiplex itself with the I/O dispatch routines which currently requires a (racey) signal based alarm system. I know there have been concerns about performance. I think so far the ones that have come up (virtio-net) are most likely due to secondary reasons like decreased batching. I think we ought to force enabling I/O thread early in 1.0 development and commit to resolving any lingering issues. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-22Replace qemu_system_cond with VCPU stop mechanismJan Kiszka
We can express the VCPU thread wakeup with the stop mechanism, saving both qemu_system_ready and the qemu_system_cond. For KVM threads, we can just enter the main loop as long as the thread is stopped. The central TCG thread is better held back before the loop as there can be side effects of the services called even when all CPUs are stopped. Creating VCPUs in stopped state will also be required for proper CPU hotplugging support. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-22Do not kick vcpus in TCG modeJan Kiszka
In TCG mode, iothread and vcpus run in lock-step. So it's pointless to send a signal from qemu_cpu_kick to the vcpu thread - if we got here, the receiver already left the vcpu loop. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-20Use glib memory allocation and free functionsAnthony Liguori
qemu_malloc/qemu_free no longer exist after this commit. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-07-23iothread: replace fair_mutex with a condition variablePaolo Bonzini
This conveys the intention better, and scales to more than >1 threads contending the mutex with the iothread (as long as all of them have a "quiescent point" like the TCG thread has). Also, on Mac OS X the fair_mutex somehow didn't work as intended and deadlocked. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Tested-by: Alexander Graf <agraf@suse.de> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-07-16Fix signal handling of SIG_IPI when io-thread is enabledAlexandre Raymond
Both the signal thread (via sigwait()) and the cpu thread (via a normal signal handler) were attempting to catch SIG_IPI. This resulted in random freezes under Darwin. This patch separates SIG_IPI from the rest of the signals handled by the signal thread, because it is independently caught by the cpu thread. Signed-off-by: Alexandre Raymond <cerbere@gmail.com> Acked-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-07-16Fix signal handling when io-thread is disabledAlexandre Raymond
Changes since v1: - take pthread_sigmask() out of the ifdef as it is now common to both parts. This fix effectively blocks, in the main thread, the signals handled by signalfd or the compatibility signal thread. This way, such signals are received synchronously in the main thread through sigfd_handler() instead of triggering the signal handler directly, asynchronously. Signed-off-by: Alexandre Raymond <cerbere@gmail.com> Acked-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-06-27Merge remote-tracking branch 'stefanha/trivial-patches' into stagingAnthony Liguori
2011-06-26Remove exec-all.h include directivesBlue Swirl
Most exec-all.h include directives are now useless, remove them. Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-06-24Do not include compatfd for WIN32Jan Kiszka
sigset_t, used by that header, is not available in mingw32 environments. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-06-20Fix typo in cpus.cAlexandre Raymond
filed -> failed Signed-off-by: Alexandre Raymond <cerbere@gmail.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-06-15Command line support for altering the log file locationMatthew Fernandez
Add command line support for logging to a location other than /tmp/qemu.log. With logging enabled (command line option -d), the log is written to the hard-coded path /tmp/qemu.log. This patch adds support for writing the log to a different location by passing the -D option. Signed-off-by: Matthew Fernandez <matthew.fernandez@gmail.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-04-15qemu_next_deadline should not consider host-time timersPaolo Bonzini
It is purely for icount-based virtual timers. And now that we got the code right, rename the function to clarify the intended scope. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Tested-by: Edgar E. Iglesias <edgar.iglesias@gmail.com> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
2011-04-15enable vm_clock to "warp" in the iothread+icount casePaolo Bonzini
The previous patch however is not enough, because if the virtual CPU goes to sleep waiting for a future timer interrupt to wake it up, qemu deadlocks. The timer interrupt never comes because time is driven by icount, but the vCPU doesn't run any insns. You could say that VCPUs should never go to sleep in icount mode if there is a pending vm_clock timer; rather time should just warp to the next vm_clock event with no sleep ever taking place. Even better, you can sleep for some time related to the time left until the next event, to avoid that the warps are too visible externally; for example, you could be sending network packets continously instead of every 100ms. This is what this patch implements. qemu_clock_warp is called: 1) whenever a vm_clock timer is adjusted, to ensure the warp_timer is synchronized; 2) at strategic points in the CPU thread, to make sure the insn counter is synchronized before the CPU starts running. In any case, the warp_timer is disabled while the CPU is running, because the insn counter will then be making progress on its own. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Tested-by: Edgar E. Iglesias <edgar.iglesias@gmail.com> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
2011-04-15really fix -icount in the iothread casePaolo Bonzini
The correct fix for -icount is to consider the biggest difference between iothread and non-iothread modes. In the traditional model, CPUs run _before_ the iothread calls select (or WaitForMultipleObjects for Win32). In the iothread model, CPUs run while the iothread isn't holding the mutex, i.e. _during_ those same calls. So, the iothread should always block as long as possible to let the CPUs run smoothly---the timeout might as well be infinite---and either the OS or the CPU thread itself will let the iothread know when something happens. At this point, the iothread wakes up and interrupts the CPU. This is exactly the approach that this patch takes: when cpu_exec_all returns in -icount mode, and it is because a vm_clock deadline has been met, it wakes up the iothread to process the timers. This is really the "bulk" of fixing icount. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Tested-by: Edgar E. Iglesias <edgar.iglesias@gmail.com> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
2011-03-21Merge remote branch 'qemu-kvm/uq/master' into stagingAnthony Liguori
2011-03-20Fix conversions from pointer to int and vice versaStefan Weil
Here the int values fds[0], sigfd, s, sock and fd are converted to void pointers which are later converted back to an int value. These conversions should always use intptr_t instead of unsigned long. They are needed for environments where sizeof(long) != sizeof(void *). Signed-off-by: Stefan Weil <weil@mail.berlios.de> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-16Expose thread_id in info cpusJan Kiszka
Based on patch by Glauber Costa: To allow management applications like libvirt to apply CPU affinities to the VCPU threads, expose their ID via info cpus. This patch provides the pre-existing and used interface from qemu-kvm. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-03-16kvm: Add in-kernel irqchip awareness to cpu_thread_is_idleJan Kiszka
With in-kernel irqchip support enabled, the vcpu threads sleep in kernel space while halted. Account for this difference in cpu_thread_is_idle. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-03-15x86: Unbreak TCG support for hardware breakpointsJan Kiszka
Commit 83f338f73e broke x86 hardware breakpoint emulation by moving the debug exception handling out of cpu_exec. Fix this by moving all TCG related bits back, only leaving the generic guest debugging parts in cpus.c. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> CC: TeLeMan <geleman@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-03-15Implement qemu_kvm_eat_signals only for CONFIG_LINUXJan Kiszka
qemu_kvm_eat_signals requires POSIX support with realtime extensions for sigtimedwait. Not all our target platforms provide this. Moreover, undefined sigbus_reraise was referenced on non-Linux as well. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> CC: Andreas Färber <andreas.faerber@web.de> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-03-13add Win32 IPI servicePaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13protect qemu_cpu_kick_self for Win32Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13provide dummy signal init functions for win32Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13merge all signal initialization with qemu_signalfd_init, renamePaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13iothread stops the vcpu thread via IPIPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13do not use timedwait on qemu_cpu_condPaolo Bonzini
Whenever env->created becomes true, qemu_cpu_cond is signaled by {kvm,tcg}_cpu_thread_fn. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13do not use timedwait on qemu_pause_condPaolo Bonzini
all_vcpus_paused can start returning true after penv->stopped changes from 0 to 1. When this is done, qemu_pause_cond is always signaled. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13do not use timedwait on qemu_system_condPaolo Bonzini
qemu_main_loop_start is the only place where qemu_system_ready is set to 1. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13do not use timedwait on qemu_halt_condPaolo Bonzini
The following conditions can cause cpu_has_work(env) to become true: - env->queued_work_first: run_on_cpu is already kicking the VCPU - env->stop = 1: pause_all_vcpus is already kicking the VCPU - env->stopped = 0: resume_all_vcpus is already kicking the VCPU - vm_running = 1: vm_start is calling resume_all_vcpus - env->halted = 0: see previous patch - qemu_cpu_has_work(env): when it becomes true, board code should set env->halted = 0 too. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13always signal pause_cond after stopping a VCPUPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13exit round-robin vcpu loop if cpu->stopped is truePaolo Bonzini
Sometimes vcpus are stopped directly without going through ->stop = 1. Exit the VCPU execution loop in this case as well. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13include qemu-thread.h earlyPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13Refactor thread retrieval and checkJan Kiszka
We have qemu_cpu_self and qemu_thread_self. The latter is retrieving the current thread, the former is checking for equality (using CPUState). We also have qemu_thread_equal which is only used like qemu_cpu_self. This refactors the interfaces, creating qemu_cpu_is_self and qemu_thread_is_self as well ass qemu_thread_get_self. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-02-16Merge remote branch 'qemu-kvm/uq/master' into stagingAnthony Liguori
2011-02-14io-thread: make sure to initialize qemu_work_cond and qemu_cpu_condAnthony Liguori
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-02-14kvm: Separate TCG from KVM cpu executionJan Kiszka
Mixing up TCG bits with KVM already led to problems around eflags emulation on x86. Moreover, quite some code that TCG requires on cpu enty/exit is useless for KVM. So dispatch between tcg_cpu_exec and kvm_cpu_exec as early as possible. The core logic of cpu_halted from cpu_exec is added to kvm_arch_process_irqchip_events. Moving away from cpu_exec makes exception_index meaningless for KVM, we can simply pass the exit reason directly (only "EXCP_DEBUG vs. rest" is relevant). Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14Move debug exception handling out of cpu_execJan Kiszka
To prepare splitting up KVM and TCG CPU entry/exit, move the debug exception into cpus.c and invoke cpu_handle_debug_exception on return from qemu_cpu_exec. This also allows to clean up the debug request signaling: We can assign the job of informing main-loop to qemu_system_debug_request and stop the calling cpu directly in cpu_handle_debug_exception. That means a debug stop will now only be signaled via debug_requested and not additionally via vmstop_requested. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14Refactor debug and vmstop request interfaceJan Kiszka
Instead of fiddling with debug_requested and vmstop_requested directly, introduce qemu_system_debug_request and turn qemu_system_vmstop_request into a public interface. This aligns those services with exiting ones in vl.c. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14Improve vm_stop reason declarationsJan Kiszka
Define and use dedicated constants for vm_stop reasons, they actually have nothing to do with the EXCP_* defines used so far. At this chance, specify more detailed reasons so that VM state change handlers can evaluate them. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14Fix a few coding style violations in cpus.cJan Kiszka
No functional changes. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14Refactor cpu_has_work/any_cpu_has_work in cpus.cJan Kiszka
Avoid duplicate use of the function name cpu_has_work, it's confusing, also their scope. Refactor cpu_has_work to cpu_thread_is_idle and do the same with any_cpu_has_work. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14Refactor kvm&tcg function names in cpus.cJan Kiszka
Pure interface cosmetics: Ensure that only kvm core services (as declared in kvm.h) start with "kvm_". Prepend "qemu_" to those that violate this rule in cpus.c. Also rename the corresponding tcg functions for the sake of consistency. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14Introduce VCPU self-signaling serviceJan Kiszka
Introduce qemu_cpu_kick_self to send SIG_IPI to the calling VCPU context. First user will be kvm. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14kvm: Add MCE signal support for !CONFIG_IOTHREADJan Kiszka
Currently, we only configure and process MCE-related SIGBUS events if CONFIG_IOTHREAD is enabled. The groundwork is laid, we just need to factor out the required handler registration and system configuration. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> CC: Huang Ying <ying.huang@intel.com> CC: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> CC: Jin Dongming <jin.dongming@np.css.fujitsu.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14kvm: Fix race between timer signals and vcpu entry under !IOTHREADJan Kiszka
Found by Stefan Hajnoczi: There is a race in kvm_cpu_exec between checking for exit_request on vcpu entry and timer signals arriving before KVM starts to catch them. Plug it by blocking both timer related signals also on !CONFIG_IOTHREAD and process those via signalfd. As this fix depends on real signalfd support (otherwise the timer signals only kick the compat helper thread, and the main thread hangs), we need to detect the invalid constellation and abort configure. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> CC: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14Set up signalfd under !CONFIG_IOTHREADJan Kiszka
Will be required for SIGBUS handling. For obvious reasons, this will remain a nop on Windows hosts. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14kvm: Call qemu_kvm_eat_signals also under !CONFIG_IOTHREADJan Kiszka
Move qemu_kvm_eat_signals around and call it also when the IO-thread is not used. Do not yet process SIGBUS, will be armed in a separate step. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14kvm: Refactor qemu_kvm_eat_signalsJan Kiszka
We do not use the timeout, so drop its logic. As we always poll our signals, we do not need to drop the global lock. Removing those calls allows some further simplifications. Also fix the error processing of sigpending at this chance. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14kvm: Set up signal mask also for !CONFIG_IOTHREADJan Kiszka
Block SIG_IPI, unblock it during KVM_RUN, just like in io-thread mode. It's unused so far, but this infrastructure will be required for self-IPIs and to process SIGBUS plus, in KVM mode, SIGIO and SIGALRM. As Windows doesn't support signal services, we need to provide a stub for the init function. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>