qemu-timer: Remove function alarm_has_dynticks

Some time ago, the last time which did not have dynticks was removed,
so now all timers have dynticks.

I also removed a misleading error message for t

qemu-timer: Remove function alarm_has_dynticks

Some time ago, the last time which did not have dynticks was removed,
so now all timers have dynticks.

I also removed a misleading error message for the dynticks timer.
If timer_create fails, there is already an error message, and
QEMU will use the unix timer which also provides dynamic ticks,
therefore dynamic ticks are not disabled.

v2:
Remove two if statements because they were always true
(thanks to Paolo Bonzini for this correction).

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>

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qemu-timer: Use bool, false, true for boolean values

This avoids conversions between int and bool / char.

It also makes the code more readable.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Sig

qemu-timer: Use bool, false, true for boolean values

This avoids conversions between int and bool / char.

It also makes the code more readable.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>

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qemu-timer: Remove unused function qemu_alarm_pending

The last user of this function was removed by commit
12d4536f7d911b6d87a766ad7300482ea663cea2.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>

qemu-timer: Remove unused function qemu_alarm_pending

The last user of this function was removed by commit
12d4536f7d911b6d87a766ad7300482ea663cea2.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>

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qemu-timer: Remove redundant include statements

qemu-timer.h includes qemu-common.h which already includes time.h,
sys/time.h, windows.h, unistd.h, fcntl.h, errno.h and signal.h.

Therefore those in

qemu-timer: Remove redundant include statements

qemu-timer.h includes qemu-common.h which already includes time.h,
sys/time.h, windows.h, unistd.h, fcntl.h, errno.h and signal.h.

Therefore those include statements are redundant and can be removed.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>

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main_loop_wait: block indefinitely

- remove qemu_calculate_timeout;

- explicitly size timeout to uint32_t;

- introduce slirp_update_timeout;

- pass NULL as timeout argument to select in case time

main_loop_wait: block indefinitely

- remove qemu_calculate_timeout;

- explicitly size timeout to uint32_t;

- introduce slirp_update_timeout;

- pass NULL as timeout argument to select in case timeout is the maximum
value;

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Paul Brook <paul@codesourcery.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

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qemu_next_alarm_deadline: check the expire time of a clock only if it is enabled

Also delta in qemu_next_alarm_deadline is a 64 bit value so set the
default to INT64_MAX instead of INT32_MAX.

Signe

qemu_next_alarm_deadline: check the expire time of a clock only if it is enabled

Also delta in qemu_next_alarm_deadline is a 64 bit value so set the
default to INT64_MAX instead of INT32_MAX.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

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timers: the rearm function should be able to handle delta = INT64_MAX

Fix win32_rearm_timer and mm_rearm_timer: they should be able to handle
INT64_MAX as a delta parameter without overflowing.
Also

timers: the rearm function should be able to handle delta = INT64_MAX

Fix win32_rearm_timer and mm_rearm_timer: they should be able to handle
INT64_MAX as a delta parameter without overflowing.
Also, the next deadline in ms should be calculated rounding down rather
than up (see unix_rearm_timer and dynticks_rearm_timer).

Finally ChangeTimerQueueTimer takes an unsigned long and timeSetEvent
takes an unsigned int as delta, so cast the ms delta to the appropriate
unsigned integer.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

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qemu-timer.c: Remove 250us timeouts

Basically, the main wait loop calls qemu_run_all_timers() unconditionally. The
first thing this routine used to do is to see if a timer had been serviced,
and the

qemu-timer.c: Remove 250us timeouts

Basically, the main wait loop calls qemu_run_all_timers() unconditionally. The
first thing this routine used to do is to see if a timer had been serviced,
and then reset the loop timeout to the next deadline.

However, the new deadlines had not been calculated at that point, as
qemu_run_timers() had not been called yet for each of the clocks. So
qemu_rearm_alarm_timer() would end up with a negative or zero deadline, and
default to setting a 250us timeout for the loop.

As qemu_run_timers() is called for each clock, the real deadlines would be put
in place, but because a loop timeout was already set, the loop timeout would
not be changed.

Once that 250us timeout fired, the real deadline would be used for the
subsequent timeout.

For idle VMs, this effectively doubles the number of times through the loop,
doubling the number of select() system calls, timer calls, etc. putting added
scheduling pressure on the kernel. And under cgroups, this really causes a big
problem because the cgroup code does not scale well.

By simply running the timers before trying to rearm the timer, we always rearm
with a non-zero deadline, effectively halving the number of system calls.

Signed-off-by: Peter Portante <pportant@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

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qtest: add clock management

This patch combines qtest and -icount together to turn the vm_clock
into a source that can be fully managed by the client. To this end new
commands clock_step and clock_

qtest: add clock management

This patch combines qtest and -icount together to turn the vm_clock
into a source that can be fully managed by the client. To this end new
commands clock_step and clock_set are added. Hooking them with libqtest
is left as an exercise to the reader.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

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notifier: switch to QLIST

Notifiers do not need to access both ends of the list, and using
a QLIST also simplifies the API.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony

notifier: switch to QLIST

Notifiers do not need to access both ends of the list, and using
a QLIST also simplifies the API.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

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remove #if 0 code for timers

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

win32: remove broken timers

The non-dynticks timer variations are broken, so they can be
removed.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.

win32: remove broken timers

The non-dynticks timer variations are broken, so they can be
removed.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

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qemu-timer: do not use RunState change handlers

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

qemu-timer: move more stuff out of qemu-timer.c

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

qemu-timer: use atexit for quit_timers

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

qemu-timer: do not refer to runstate_is_running()

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

qemu-timer: move icount to cpus.c

None of this is needed by tools, and most of it can even be made static
inside cpus.c.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

qemu-timer: more clock functions

These will be used when moving icount accounting to cpus.c.

Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

qemu-timer: move common code to qemu_rearm_alarm_timer

Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

qemu-timer: remove active_timers array

Embed the list in the QEMUClock instead.

Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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>

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 VMST

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>

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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 VC

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>

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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>

Register Linux dyntick timer as per-thread signal

Derived from kvm-tool patch
http://thread.gmane.org/gmane.comp.emulators.kvm.devel/74309

Ingo Molnar pointed out that sending the timer signal to t

Register Linux dyntick timer as per-thread signal

Derived from kvm-tool patch
http://thread.gmane.org/gmane.comp.emulators.kvm.devel/74309

Ingo Molnar pointed out that sending the timer signal to the whole
process, just blocking it everywhere, is suboptimal with an increasing
number of threads. QEMU is also using this pattern so far.

Linux provides a (non-portable) way to restrict the signal to a single
thread: We can use SIGEV_THREAD_ID unless we are forced to emulate
signalfd via an additional thread. That case could theoretically be
optimized as well, but it doesn't look worth bothering.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

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