Commit graph

235 commits

Author SHA1 Message Date
Frediano Ziglio
e1d3b25499 block: avoid SIGUSR2
Now that iothread is always compiled sending a signal seems only an
additional step. This patch also avoid writing to two pipe (one from signal
and one in qemu_service_io).

Work with kvm enabled or disabled. strace output is more readable (less syscalls).

[ kwolf: Merged build fix by Paolo Bonzini ]

Signed-off-by: Frediano Ziglio <freddy77@gmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-20 14:32:56 +02:00
Luiz Capitulino
1354869c38 Drop the vm_running global variable
Use runstate_is_running() instead, which is introduced by this commit.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2011-09-15 16:39:32 -03:00
Luiz Capitulino
f5bbfba1eb RunState: Add additional states
Currently, only vm_start() and vm_stop() change the VM state.
That's, the state is only changed when starting or stopping the VM.

This commit adds the runstate_set() function, which makes it possible
to also do state transitions when the VM is stopped or running.

Additional states are also added and the current state is stored.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2011-09-15 16:39:32 -03:00
Luiz Capitulino
1dfb4dd993 Replace the VMSTOP macros with a proper state type
Today, when notifying a VM state change with vm_state_notify(),
we pass a VMSTOP macro as the 'reason' argument. This is not ideal
because the VMSTOP macros tell why qemu stopped and not exactly
what the current VM state is.

One example to demonstrate this problem is that vm_start() calls
vm_state_notify() with reason=0, which turns out to be VMSTOP_USER.

This commit fixes that by replacing the VMSTOP macros with a proper
state type called RunState.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2011-09-15 16:39:32 -03:00
Anthony Liguori
12d4536f7d main: force enabling of I/O thread
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>
2011-09-02 10:34:55 -05:00
Jan Kiszka
fa7d186757 Replace qemu_system_cond with VCPU stop mechanism
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>
2011-08-22 14:37:03 -05:00
Jan Kiszka
eae74cf906 Do not kick vcpus in TCG mode
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>
2011-08-22 14:37:02 -05:00
Anthony Liguori
7267c0947d Use glib memory allocation and free functions
qemu_malloc/qemu_free no longer exist after this commit.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-20 23:01:08 -05:00
Paolo Bonzini
46daff13c8 iothread: replace fair_mutex with a condition variable
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>
2011-07-23 11:18:51 -05:00
Alexandre Raymond
89b9ba661b Fix signal handling of SIG_IPI when io-thread is enabled
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>
2011-07-16 19:43:00 +00:00
Alexandre Raymond
5664aed99a Fix signal handling when io-thread is disabled
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>
2011-07-16 19:41:08 +00:00
Anthony Liguori
bb820c03e2 Merge remote-tracking branch 'stefanha/trivial-patches' into staging 2011-06-27 11:25:23 -05:00
Blue Swirl
2b41f10e18 Remove exec-all.h include directives
Most exec-all.h include directives are now useless, remove them.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-06-26 18:25:35 +00:00
Jan Kiszka
0ff0fc19cd Do not include compatfd for WIN32
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>
2011-06-24 09:13:37 +01:00
Alexandre Raymond
77bec68668 Fix typo in cpus.c
filed -> failed

Signed-off-by: Alexandre Raymond <cerbere@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-06-20 16:42:35 +01:00
Matthew Fernandez
c235d7387c Command line support for altering the log file location
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>
2011-06-15 16:51:24 +00:00
Paolo Bonzini
cb842c90a4 qemu_next_deadline should not consider host-time timers
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>
2011-04-15 09:27:56 +02:00
Paolo Bonzini
ab33fcda9f enable vm_clock to "warp" in the iothread+icount case
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>
2011-04-15 09:27:56 +02:00
Paolo Bonzini
3b2319a30b really fix -icount in the iothread case
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>
2011-04-15 09:27:56 +02:00
Anthony Liguori
31b7c261a2 Merge remote branch 'qemu-kvm/uq/master' into staging 2011-03-21 17:42:20 -05:00
Stefan Weil
e0efb993b8 Fix conversions from pointer to int and vice versa
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>
2011-03-20 21:39:23 +00:00
Jan Kiszka
dc7a09cfe4 Expose thread_id in info cpus
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>
2011-03-16 17:11:07 -03:00
Jan Kiszka
f2c1cc81c8 kvm: Add in-kernel irqchip awareness to cpu_thread_is_idle
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>
2011-03-16 17:11:05 -03:00
Jan Kiszka
1009d2edea x86: Unbreak TCG support for hardware breakpoints
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>
2011-03-15 14:36:25 -03:00
Jan Kiszka
1ab3c6c073 Implement qemu_kvm_eat_signals only for CONFIG_LINUX
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>
2011-03-15 14:36:25 -03:00
Paolo Bonzini
cc015e9a5d add Win32 IPI service
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13 14:44:22 +00:00
Paolo Bonzini
b55c22c65b protect qemu_cpu_kick_self for Win32
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13 14:44:22 +00:00
Paolo Bonzini
714bd04090 provide dummy signal init functions for win32
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13 14:44:22 +00:00
Paolo Bonzini
712ae48084 merge all signal initialization with qemu_signalfd_init, rename
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13 14:44:22 +00:00
Paolo Bonzini
8cf3f22b77 iothread stops the vcpu thread via IPI
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13 14:44:22 +00:00
Paolo Bonzini
18a857280d do not use timedwait on qemu_cpu_cond
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>
2011-03-13 14:44:22 +00:00
Paolo Bonzini
be7d6c57c4 do not use timedwait on qemu_pause_cond
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>
2011-03-13 14:44:22 +00:00
Paolo Bonzini
e009894f08 do not use timedwait on qemu_system_cond
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>
2011-03-13 14:44:22 +00:00
Paolo Bonzini
9705fbb563 do not use timedwait on qemu_halt_cond
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>
2011-03-13 14:44:22 +00:00
Paolo Bonzini
67bb172f9d always signal pause_cond after stopping a VCPU
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13 14:44:21 +00:00
Paolo Bonzini
df646dfd56 exit round-robin vcpu loop if cpu->stopped is true
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>
2011-03-13 14:44:21 +00:00
Paolo Bonzini
96284e8973 include qemu-thread.h early
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-03-13 14:44:21 +00:00
Jan Kiszka
b7680cb607 Refactor thread retrieval and check
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>
2011-03-13 14:44:21 +00:00
Anthony Liguori
c5d69e6bbf Merge remote branch 'qemu-kvm/uq/master' into staging 2011-02-16 08:47:07 -06:00
Anthony Liguori
ed94592be2 io-thread: make sure to initialize qemu_work_cond and qemu_cpu_cond
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-02-14 08:43:30 -06:00
Jan Kiszka
6792a57bf1 kvm: Separate TCG from KVM cpu execution
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>
2011-02-14 12:39:46 -02:00
Jan Kiszka
83f338f73e Move debug exception handling out of cpu_exec
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>
2011-02-14 12:39:46 -02:00
Jan Kiszka
8cf71710f0 Refactor debug and vmstop request interface
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>
2011-02-14 12:39:46 -02:00
Jan Kiszka
e07bbac542 Improve vm_stop reason declarations
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>
2011-02-14 12:39:46 -02:00
Jan Kiszka
0ab07c623c Fix a few coding style violations in cpus.c
No functional changes.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14 12:39:46 -02:00
Jan Kiszka
1640032283 Refactor cpu_has_work/any_cpu_has_work in cpus.c
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>
2011-02-14 12:39:46 -02:00
Jan Kiszka
7e97cd8814 Refactor kvm&tcg function names in cpus.c
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>
2011-02-14 12:39:46 -02:00
Jan Kiszka
46d62fac8a Introduce VCPU self-signaling service
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>
2011-02-14 12:39:45 -02:00
Jan Kiszka
6d9cb73c1b kvm: Add MCE signal support for !CONFIG_IOTHREAD
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>
2011-02-14 12:39:45 -02:00
Jan Kiszka
de758970b6 kvm: Fix race between timer signals and vcpu entry under !IOTHREAD
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>
2011-02-14 12:39:45 -02:00
Jan Kiszka
d0f294cec0 Set up signalfd under !CONFIG_IOTHREAD
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>
2011-02-14 12:39:45 -02:00
Jan Kiszka
9a36085b86 kvm: Call qemu_kvm_eat_signals also under !CONFIG_IOTHREAD
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>
2011-02-14 12:39:45 -02:00
Jan Kiszka
5db5bdacdf kvm: Refactor qemu_kvm_eat_signals
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>
2011-02-14 12:39:45 -02:00
Jan Kiszka
ff48eb5fe7 kvm: Set up signal mask also for !CONFIG_IOTHREAD
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>
2011-02-14 12:39:45 -02:00
Jan Kiszka
55f8d6ac3e Refactor signal setup functions in cpus.c
Move {tcg,kvm}_init_ipi and block_io_signals to avoid prototypes, rename
the former two to clarify that they deal with more than SIG_IPI. No
functional changes - except for the tiny fixup of strerror usage.

The forward declaration of sigbus_handler is just temporarily, it will
be moved in a succeeding patch. dummy_signal is moved into the !_WIN32
block as we will soon need it also for !CONFIG_IOTHREAD.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14 12:39:45 -02:00
Jan Kiszka
a1b87fe046 kvm: Provide sigbus services arch-independently
Provide arch-independent kvm_on_sigbus* stubs to remove the #ifdef'ery
from cpus.c. This patch also fixes --disable-kvm build by providing the
missing kvm_on_sigbus_vcpu kvm-stub.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14 12:39:45 -02:00
Jan Kiszka
84b4915dd2 kvm: Handle kvm_init_vcpu errors
Do not ignore errors of kvm_init_vcpu, they are fatal.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14 12:39:45 -02:00
Jan Kiszka
d31ae052a9 kvm: Drop redundant kvm_enabled from kvm_cpu_thread_fn
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14 12:39:45 -02:00
Jan Kiszka
38145df24c Trigger exit from cpu_exec_all on pending IO events
Except for timer events, we currently do not leave the loop over all
VCPUs if an IO event was filed. That may cause unexpected IO latencies
under !CONFIG_IOTHREAD in SMP scenarios. Fix it by setting the global
exit_request which breaks the loop.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14 12:39:44 -02:00
Jan Kiszka
b4a3d965de Stop current VCPU on synchronous reset requests
If some I/O operation ends up calling qemu_system_reset_request in VCPU
context, we record this and inform the io-thread, but we do not
terminate the VCPU loop. This can lead to fairly unexpected behavior if
the triggering reset operation is supposed to work synchronously.

Fix this for TCG (when run in deterministic I/O mode) by setting the
VCPU on stop and issuing a cpu_exit. KVM requires some more work on its
VCPU loop.

[ ported from qemu-kvm ]

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14 12:39:44 -02:00
Jan Kiszka
aa2c364b4c Prevent abortion on multiple VCPU kicks
If we call qemu_cpu_kick more than once before the target was able to
process the signal, pthread_kill will fail, and qemu will abort. Prevent
this by avoiding the redundant signal.

This logic can be found in qemu-kvm as well.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-02-14 12:39:44 -02:00
Jan Kiszka
b66042c722 kvm: Do not use qemu_fair_mutex
The imbalance in the hold time of qemu_global_mutex only exists in TCG
mode. In contrast to TCG VCPUs, KVM drops the global lock during guest
execution. We already avoid touching the fairness lock from the
IO-thread in KVM mode, so also stop using it from the VCPU threads.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-23 02:27:22 -02:00
Michael S. Tsirkin
55df6f3365 cpus: flush all requests on each vm stop
Flush all requests once we have stopped all
cpus and devices.
Make sure disk is in consistent state.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Jason Wang <jasowang@redhat.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-12-09 12:47:19 +02:00
Stefan Weil
9a78eead0c target-xxx: Use fprintf_function (format checking)
fprintf_function uses format checking with GCC_FMT_ATTR.

Format errors were fixed in
* target-i386/helper.c
* target-mips/translate.c
* target-ppc/translate.c

Cc: Blue Swirl <blauwirbel@gmail.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-10-30 08:01:59 +00:00
Marcelo Tosatti
c0532a76b4 MCE: Relay UCR MCE to guest
Port qemu-kvm's

commit 4b62fff1101a7ad77553147717a8bd3bf79df7ef
Author: Huang Ying <ying.huang@intel.com>
Date:   Mon Sep 21 10:43:25 2009 +0800

    MCE: Relay UCR MCE to guest

    UCR (uncorrected recovery) MCE is supported in recent Intel CPUs,
    where some hardware error such as some memory error can be reported
    without PCC (processor context corrupted). To recover from such MCE,
    the corresponding memory will be unmapped, and all processes accessing
    the memory will be killed via SIGBUS.

    For KVM, if QEMU/KVM is killed, all guest processes will be killed
    too. So we relay SIGBUS from host OS to guest system via a UCR MCE
    injection. Then guest OS can isolate corresponding memory and kill
    necessary guest processes only. SIGBUS sent to main thread (not VCPU
    threads) will be broadcast to all VCPU threads as UCR MCE.

aliguori: fix build

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-10-20 16:15:04 -05:00
Marcelo Tosatti
a8486bc9c9 iothread: use signalfd
Block SIGALRM, SIGIO and consume them via signalfd.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-20 16:15:04 -05:00
Jan Kiszka
3c638d0690 Rework debug exception processing for gdb use
Guest debugging is currently broken under CONFIG_IOTHREAD. The reason is
inconsistent or even lacking signaling the debug events from the source
VCPU to the main loop and the gdbstub.

This patch addresses the issue by pushing this signaling into a
CPUDebugExcpHandler: cpu_debug_handler is registered as first handler,
thus will be executed last after potential breakpoint emulation
handlers. It sets informs the gdbstub about the debug event source,
requests a debug exit of the main loop and stops the current VCPU. This
mechanism works both for TCG and KVM, with and without IO-thread.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2010-07-22 05:52:09 +02:00
Jan Kiszka
472fb0c479 Rename tcg_cpu_exec and tcg_has_work
These functions are also used for kvm under !CONFIG_IOTHREAD, having
'tcg' in their name is just misleading.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2010-07-22 05:52:09 +02:00
Jan Kiszka
345f4426a9 Drop redundant global cur_cpu variable
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2010-07-22 05:52:09 +02:00
Jan Kiszka
6cabe1f303 Fix qemu_wait_io_event processing in io-thread mode
When checking for I/O events in the tcg CPU loop, make sure that we
call qemu_wait_io_event_common for all CPUs, not only the current one.
Otherwise pause_all_vcpus may lock up or run_on_cpu requests may starve.

Rename qemu_wait_io_event to qemu_tcg_wait_io_event at this chance and
purge its argument list as it has no use for it.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2010-07-22 05:52:09 +02:00
Jan Kiszka
c629a4bc97 Fix cpu_exit for tcp_cpu_exec
If a cpu_exit request is pending, ensure that we leave the CPU loop
quickly. For this purpose, keep the global exit_request pending until
we are about to leave tcg_cpu_exec. Also, immediately break out of the
SMP loop if the request is set, do not run till the end of the chain.
This preserves the VCPU scheduling order in SMP mode.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2010-07-22 05:52:09 +02:00
Jan Kiszka
f8ca7b43a5 Init qemu_system_cond
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2010-07-22 05:52:09 +02:00
Jan Kiszka
262ea18e89 Fix io-thread build breakage of a88790a14f
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-07-06 10:36:19 -05:00
Paolo Bonzini
55541c8afc make qemu_thread_create block all signals
All signals will thus be routed through the IO thread.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-06-14 15:46:28 -05:00
Blue Swirl
26a823305d cpus: add one 'const'
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-05-14 19:32:21 +00:00
Marcelo Tosatti
3ae9501c5b add cpu_is_stopped helper
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-11 14:02:22 -03:00
Marcelo Tosatti
e82bcec25f port qemu-kvm's on_vcpu code
run_on_cpu allows to execute work on a given CPUState context.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-11 14:02:22 -03:00
Marcelo Tosatti
1fbb22e5f8 standardize on qemu_cpu_kick for signalling cpu thread(s)
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-11 14:02:22 -03:00
Marcelo Tosatti
1a28cac316 make SIG_IPI to tcg vcpu thread reliable
Store tcg loop exit request on a global variable, and transfer it to
per-CPUState exit_request after assignment of cpu_single_env.

This makes exit request signal from robust. Drop the timedlock hack.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-11 14:02:22 -03:00
Blue Swirl
262353cb1f Fix cpu list("-cpu ?") breakage, spotted by TeLeMan
Fix breakage by 04c9a0cbc2.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-05-04 19:55:35 +00:00
Marcelo Tosatti
6164e6d6e8 kvm_init_vcpu requires global lock held
Since it accesses data protected by the lock.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-26 11:28:35 -03:00
Blue Swirl
7277e027bb Fix build when configured with --enable-io-thread
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-04-12 17:19:06 +00:00
Paolo Bonzini
55274a3052 fix 100% cpu utilization when cpu is stopped
> Hello,
>
> d6f4ade (disentangle tcg and deadline calculation, 2010-03-10)
> introduces following regression(s):
>
> 100% cpu utilization when QEMU is invoked like:
> qemu -S -s ...
>
> ditto when gdb takes control over the session via gdb-stub
> (i.e. the breakpoint is hit or C-c is pressed inside gdb to
>   interrupt the attached qemu instance)

The bug is that env->stopped is not really as comprehensive as it seems to
be (and cpu_has_work thinks); it is only valid with iothread basically,
and even then it is cleared by reset and it is not set when starting
qemu with -S.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: malc <av1474@comtv.ru>
Signed-off-by: malc <av1474@comtv.ru>
2010-04-07 02:24:58 +04:00
Blue Swirl
29e922b61f Compile qemu-timer only once
Arrange various declarations so that also non-CPU code can access
them, adjust users.

Move CPU specific code to cpus.c.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-03-29 19:24:00 +00:00
Blue Swirl
296af7c952 Refactor CPUState handling out of vl.c
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-03-29 19:23:50 +00:00