Commit Graph

431 Commits

Author SHA1 Message Date
Peter Maydell f22f553eff Host vector support for tcg/ppc.
Fix thread=single cpu kicking.
 -----BEGIN PGP SIGNATURE-----
 
 iQFRBAABCgA7FiEEekgeeIaLTbaoWgXAZN846K9+IV8FAl2kgisdHHJpY2hhcmQu
 aGVuZGVyc29uQGxpbmFyby5vcmcACgkQZN846K9+IV/q+wgAoQQYDvjzdmZUyCFx
 DIf5FyRcx7bvrrWsfkRLs4Pwbo49LUcX400P/oZvGXs/ATiEmBTT+nSXWYBeLzY/
 XeEhZM6U6lOkzqZF5RKdXpHb+YBe6HOQVpkKOSDlmf6H45B3J8lhten0pp0a2OK0
 c3uxTQmR6uowbqWRwl3//pP98ynqjEmnrTh2+4fqF8idM5LlfGtlXA8Ga665RAYn
 TXcJ/bfDyRMTk1ubSxhTa8wiNxs8ihjrPNADbBQma4z6KgbhZ/1iMi8G82vcG3H3
 qLAg7o9u2FUGxDo2tPyFSTpElvuf7XoNROQfvvSLEPCnhp3Xqt5mXRFxXFEnAsv1
 RFHsyg==
 =pW3Z
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/rth/tags/pull-tcg-20191013' into staging

Host vector support for tcg/ppc.
Fix thread=single cpu kicking.

# gpg: Signature made Mon 14 Oct 2019 15:11:55 BST
# gpg:                using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
# gpg:                issuer "richard.henderson@linaro.org"
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [full]
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A  05C0 64DF 38E8 AF7E 215F

* remotes/rth/tags/pull-tcg-20191013: (23 commits)
  cpus: kick all vCPUs when running thread=single
  tcg/ppc: Update vector support for v3.00 dup/dupi
  tcg/ppc: Update vector support for v3.00 load/store
  tcg/ppc: Update vector support for v3.00 Altivec
  tcg/ppc: Update vector support for v2.07 FP
  tcg/ppc: Update vector support for v2.07 VSX
  tcg/ppc: Update vector support for v2.07 Altivec
  tcg/ppc: Update vector support for VSX
  tcg/ppc: Enable Altivec detection
  tcg/ppc: Support vector dup2
  tcg/ppc: Support vector multiply
  tcg/ppc: Support vector shift by immediate
  tcg/ppc: Add support for vector saturated add/subtract
  tcg/ppc: Add support for vector add/subtract
  tcg/ppc: Add support for vector maximum/minimum
  tcg/ppc: Add support for load/store/logic/comparison
  tcg/ppc: Enable tcg backend vector compilation
  tcg/ppc: Replace HAVE_ISEL macro with a variable
  tcg/ppc: Replace HAVE_ISA_2_06
  tcg/ppc: Create TCGPowerISA and have_isa
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-10-17 16:48:56 +01:00
Pavel Dovgalyuk c8aa7895eb replay: don't drain/flush bdrv queue while RR is working
In record/replay mode bdrv queue is controlled by replay mechanism.
It does not allow saving or loading the snapshots
when bdrv queue is not empty. Stopping the VM is not blocked by nonempty
queue, but flushing the queue is still impossible there,
because it may cause deadlocks in replay mode.
This patch disables bdrv_drain_all and bdrv_flush_all in
record/replay mode.

Stopping the machine when the IO requests are not finished is needed
for the debugging. E.g., breakpoint may be set at the specified step,
and forcing the IO requests to finish may break the determinism
of the execution.

Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-10-14 17:12:48 +02:00
Alex Bennée e8f22f7684 cpus: kick all vCPUs when running thread=single
qemu_cpu_kick is used for a number of reasons including to indicate
there is work to be done. However when thread=single the old
qemu_cpu_kick_rr_cpu only advanced the vCPU to the next executing one
which can lead to a hang in the case that:

  a) the kick is from outside the vCPUs (e.g. iothread)
  b) the timers are paused (i.e. iothread calling run_on_cpu)

To avoid this lets split qemu_cpu_kick_rr into two functions. One for
the timer which continues to advance to the next timeslice and another
for all other kicks.

Message-Id: <20191001160426.26644-1-alex.bennee@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-10-14 07:10:57 -07:00
Yury Kotov bd1f7ff4b2 cpus: Fix throttling during vm_stop
Throttling thread sleeps in VCPU thread. For high throttle percentage
this sleep is more than 10ms. E.g. for 60% - 15ms, for 99% - 990ms.
vm_stop() kicks all VCPUs and waits for them. It's called at the end of
migration and because of the long sleep the migration downtime might be
more than 100ms even for downtime-limit 1ms.
Use qemu_cond_timedwait for high percentage to wake up during vm_stop.

Signed-off-by: Yury Kotov <yury-kotov@yandex-team.ru>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190909131335.16848-3-yury-kotov@yandex-team.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-09-16 17:13:07 +02:00
Pavel Dovgalyuk dcb1578069 util/qemu-timer: refactor deadline calculation for external timers
icount-based record/replay uses qemu_clock_deadline_ns_all to measure
the period until vCPU may be interrupted.
This function takes in account the virtual timers, because they belong
to the virtual devices that may generate interrupt request or affect
the virtual machine state.
However, there are a subset of virtual timers, that are marked with
'external' flag. These do not change the virtual machine state and
only based on virtual clock. Calculating the deadling using the external
timers breaks the determinism, because they do not belong to the replayed
part of the virtual machine.
This patch fixes the deadline calculation for this case by adding
new parameter for skipping the external timers when it is needed.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>

--

v2 changes:
 - added new parameter for timer attribute mask
Message-Id: <156404426682.18669.17014100602930969222.stgit@pasha-Precision-3630-Tower>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-08-20 17:26:21 +02:00
Markus Armbruster 54d31236b9 sysemu: Split sysemu/runstate.h off sysemu/sysemu.h
sysemu/sysemu.h is a rather unfocused dumping ground for stuff related
to the system-emulator.  Evidence:

* It's included widely: in my "build everything" tree, changing
  sysemu/sysemu.h still triggers a recompile of some 1100 out of 6600
  objects (not counting tests and objects that don't depend on
  qemu/osdep.h, down from 5400 due to the previous two commits).

* It pulls in more than a dozen additional headers.

Split stuff related to run state management into its own header
sysemu/runstate.h.

Touching sysemu/sysemu.h now recompiles some 850 objects.  qemu/uuid.h
also drops from 1100 to 850, and qapi/qapi-types-run-state.h from 4400
to 4200.  Touching new sysemu/runstate.h recompiles some 500 objects.

Since I'm touching MAINTAINERS to add sysemu/runstate.h anyway, also
add qemu/main-loop.h.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-30-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
[Unbreak OS-X build]
2019-08-16 13:37:36 +02:00
Markus Armbruster 46517dd497 Include sysemu/sysemu.h a lot less
In my "build everything" tree, changing sysemu/sysemu.h triggers a
recompile of some 5400 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).

hw/qdev-core.h includes sysemu/sysemu.h since recent commit e965ffa70a
"qdev: add qdev_add_vm_change_state_handler()".  This is a bad idea:
hw/qdev-core.h is widely included.

Move the declaration of qdev_add_vm_change_state_handler() to
sysemu/sysemu.h, and drop the problematic include from hw/qdev-core.h.

Touching sysemu/sysemu.h now recompiles some 1800 objects.
qemu/uuid.h also drops from 5400 to 1800.  A few more headers show
smaller improvement: qemu/notify.h drops from 5600 to 5200,
qemu/timer.h from 5600 to 4500, and qapi/qapi-types-run-state.h from
5500 to 5000.

Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20190812052359.30071-28-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2019-08-16 13:31:53 +02:00
Markus Armbruster 650d103d3e Include hw/hw.h exactly where needed
In my "build everything" tree, changing hw/hw.h triggers a recompile
of some 2600 out of 6600 objects (not counting tests and objects that
don't depend on qemu/osdep.h).

The previous commits have left only the declaration of hw_error() in
hw/hw.h.  This permits dropping most of its inclusions.  Touching it
now recompiles less than 200 objects.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-19-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16 13:31:52 +02:00
Markus Armbruster d645427057 Include migration/vmstate.h less
In my "build everything" tree, changing migration/vmstate.h triggers a
recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).

hw/hw.h supposedly includes it for convenience.  Several other headers
include it just to get VMStateDescription.  The previous commit made
that unnecessary.

Include migration/vmstate.h only where it's still needed.  Touching it
now recompiles only some 1600 objects.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-16-armbru@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16 13:31:52 +02:00
Like Xu 5cc8767d05 general: Replace global smp variables with smp machine properties
Basically, the context could get the MachineState reference via call
chains or unrecommended qdev_get_machine() in !CONFIG_USER_ONLY mode.

A local variable of the same name would be introduced in the declaration
phase out of less effort OR replace it on the spot if it's only used
once in the context. No semantic changes.

Signed-off-by: Like Xu <like.xu@linux.intel.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190518205428.90532-4-like.xu@linux.intel.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2019-07-05 17:07:36 -03:00
Markus Armbruster 52924dea17 hw/core: Collect QMP command handlers in hw/core/
The handlers for qapi/machine.json's QMP commands are spread over
cpus.c, hw/core/numa.c, monitor/misc.c, monitor/qmp-cmds.c, and vl.c.
Move them all to new hw/core/machine-qmp-cmds.c, where they are
covered by MAINTAINERS section "Machine core", just like
qapi/machine.json.

Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190619201050.19040-11-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-07-02 13:37:00 +02:00
Markus Armbruster 8ac25c8442 qapi: Split machine.json off misc.json
Move commands cpu-add, query-cpus, query-cpus-fast,
query-current-machine, query-hotpluggable-cpus, query-machines,
query-memdev, and set-numa-node with their types from misc.json to new
machine.json.  Also move types X86CPURegister32 and
X86CPUFeatureWordInfo.  Add machine.json to MAINTAINERS section
"Machine core".

Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190619201050.19040-9-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-07-02 13:37:00 +02:00
Colin Xu 6f38dca615 hax: Honor CPUState::halted
QEMU tracks whether a vcpu is halted using CPUState::halted. E.g.,
after initialization or reset, halted is 0 for the BSP (vcpu 0)
and 1 for the APs (vcpu 1, 2, ...). A halted vcpu should not be
handed to the hypervisor to run (e.g. hax_vcpu_run()).

Under HAXM, Android Emulator sometimes boots into a "vcpu shutdown
request" error while executing in SeaBIOS, with the HAXM driver
logging a guest triple fault in vcpu 1, 2, ... at RIP 0x3. That is
ultimately because the HAX accelerator asks HAXM to run those APs
when they are still in the halted state.

Normally, the vcpu thread for an AP will start by looping in
qemu_wait_io_event(), until the BSP kicks it via a pair of IPIs
(INIT followed by SIPI). But because the HAX accelerator does not
honor cpu->halted, it allows the AP vcpu thread to proceed to
hax_vcpu_run() as soon as it receives any kick, even if the kick
does not come from the BSP. It turns out that emulator has a
worker thread which periodically kicks every vcpu thread (possibly
to collect CPU usage data), and if one of these kicks comes before
those by the BSP, the AP will start execution from the wrong RIP,
resulting in the aforementioned SMP boot failure.

The solution is inspired by the KVM accelerator (credit to
Chuanxiao Dong <chuanxiao.dong@intel.com> for the pointer):

1. Get rid of questionable logic that unconditionally resets
   cpu->halted before hax_vcpu_run(). Instead, only reset it at the
   right moments (there are only a few "unhalt" events).
2. Add a check for cpu->halted before hax_vcpu_run().

Note that although the non-Unrestricted Guest (!ug_platform) code
path also forcibly resets cpu->halted, it is left untouched,
because only the UG code path supports SMP guests.

The patch is first merged to android emulator with Change-Id:
I9c5752cc737fd305d7eace1768ea12a07309d716

Cc: Yu Ning <yu.ning@intel.com>
Cc: Chuanxiao Dong <chuanxiao.dong@intel.com>
Signed-off-by: Colin Xu <colin.xu@intel.com>
Message-Id: <20190610021939.13669-1-colin.xu@intel.com>
2019-06-21 02:29:38 +02:00
Markus Armbruster a8d2532645 Include qemu-common.h exactly where needed
No header includes qemu-common.h after this commit, as prescribed by
qemu-common.h's file comment.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-5-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c
block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c
target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h
target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h
target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h
target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and
net/tap-bsd.c fixed up]
2019-06-12 13:20:20 +02:00
Markus Armbruster 14a48c1d0d qemu-common: Move tcg_enabled() etc. to sysemu/tcg.h
Other accelerators have their own headers: sysemu/hax.h, sysemu/hvf.h,
sysemu/kvm.h, sysemu/whpx.h.  Only tcg_enabled() & friends sit in
qemu-common.h.  This necessitates inclusion of qemu-common.h into
headers, which is against the rules spelled out in qemu-common.h's
file comment.

Move tcg_enabled() & friends into their own header sysemu/tcg.h, and
adjust #include directives.

Cc: Richard Henderson <rth@twiddle.net>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-2-armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[Rebased with conflicts resolved automatically, except for
accel/tcg/tcg-all.c]
2019-06-11 20:22:09 +02:00
Richard Henderson 5e1401969b cpu: Move icount_decr to CPUNegativeOffsetState
Amusingly, we had already ignored the comment to keep this value
at the end of CPUState.  This restores the minimum negative offset
from TCG_AREG0 for code generation.

For the couple of uses within qom/cpu.c, without NEED_CPU_H, add
a pointer from the CPUState object to the IcountDecr object within
CPUNegativeOffsetState.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10 07:03:42 -07:00
Richard Henderson 9c09a2518e cpus: Initialize pseudo-random seeds for all guest cpus
When the -seed option is given, call qemu_guest_random_seed_main,
putting the subsystem into deterministic mode.  Pass derived seeds
to each cpu created; which is a no-op unless the subsystem is in
deterministic mode.

Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-05-22 12:38:54 -04:00
Markus Armbruster 90c84c5600 qom/cpu: Simplify how CPUClass:cpu_dump_state() prints
CPUClass method dump_statistics() takes an fprintf()-like callback and
a FILE * to pass to it.  Most callers pass fprintf() and stderr.
log_cpu_state() passes fprintf() and qemu_log_file.
hmp_info_registers() passes monitor_fprintf() and the current monitor
cast to FILE *.  monitor_fprintf() casts it right back, and is
otherwise identical to monitor_printf().

The callback gets passed around a lot, which is tiresome.  The
type-punning around monitor_fprintf() is ugly.

Drop the callback, and call qemu_fprintf() instead.  Also gets rid of
the type-punning, since qemu_fprintf() takes NULL instead of the
current monitor cast to FILE *.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-15-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
Markus Armbruster 0442428a89 target: Simplify how the TARGET_cpu_list() print
The various TARGET_cpu_list() take an fprintf()-like callback and a
FILE * to pass to it.  Their callers (vl.c's main() via list_cpus(),
bsd-user/main.c's main(), linux-user/main.c's main()) all pass
fprintf() and stdout.  Thus, the flexibility provided by the (rather
tiresome) indirection isn't actually used.

Drop the callback, and call qemu_printf() instead.

Calling printf() would also work, but would make the code unsuitable
for monitor context without making it simpler.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190417191805.28198-10-armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-04-18 22:18:59 +02:00
Markus Armbruster 76c8661595 tcg: Simplify how dump_drift_info() prints
dump_drift_info() takes an fprintf()-like callback and a FILE * to pass
to it.

Its only caller hmp_info_jit() passes monitor_fprintf() and a Monitor
* cast to FILE *.  monitor_fprintf() casts it right back, and is
otherwise identical to monitor_printf().  The type-punning is ugly.

Drop the callback, and call qemu_printf() instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-6-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
David Hildenbrand d40bfcbbbb cpus: Properly release the iothread lock when killing a dummy VCPU
This enables CPU unplug under qtest.

Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218092202.26683-2-david@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-02-26 09:21:25 +11:00
Laurent Vivier d455ebc4f8 cpus: ignore ESRCH in qemu_cpu_kick_thread()
We can have a race condition between qemu_cpu_kick_thread() and
qemu_kvm_cpu_thread_fn() when we hotunplug a CPU. In this case,
qemu_cpu_kick_thread() can try to kick a thread that is exiting.
pthread_kill() returns an error and qemu is stopped by an exit(1).

   qemu:qemu_cpu_kick_thread: No such process

We can ignore safely this error.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-02-05 16:50:16 +01:00
Peter Maydell 0ec7e6779f cpus.c: Fix race condition in cpu_stop_current()
We use cpu_stop_current() to ensure the current CPU has stopped
from places like qemu_system_reset_request(). Unfortunately its
current implementation has a race. It calls qemu_cpu_stop(),
which sets cpu->stopped to true even though the CPU hasn't
actually stopped yet. The main thread will look at the flags
set by qemu_system_reset_request() and call pause_all_vcpus().
pause_all_vcpus() waits for every cpu to have cpu->stopped true,
so it can continue (and we will start the system reset operation)
before the vcpu thread has got back to its top level loop.

Instead, just set cpu->stop and call cpu_exit(). This will
cause the vcpu to exit back to the top level loop, and there
(as part of the wait_io_event code) it will call qemu_cpu_stop().

This fixes bugs where the reset request appeared to be ignored
or the CPU misbehaved because the reset operation started
to change vcpu state while the vcpu thread was still using it.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Tested-by: Jaap Crezee <jaap@jcz.nl>
Message-id: 20181207155911.12710-1-peter.maydell@linaro.org
2019-01-07 15:23:47 +00:00
Paolo Bonzini a8efa60633 cpus: run work items for all vCPUs if single-threaded
This avoids the following I/O thread deadlock:

1) the I/O thread calls run_on_cpu for CPU 3 from a timer.  single_tcg_halt_cond
is signaled

2) CPU 1 is running and exits.  It finds no work item and enters CPU 2

3) because the I/O thread is stuck in run_on_cpu, the round-robin kick
timer never triggers, and CPU 3 never runs the work item

4) run_on_cpu never completes

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-11-27 15:06:14 +01:00
Clement Deschamps 013aabdc66 icount: fix deadlock when all cpus are sleeping
When all cpus are sleeping (e.g in WFI), to avoid a deadlock
in the main_loop, wake it up in order to start the warp timer.

Signed-off-by: Clement Deschamps <clement.deschamps@greensocs.com>
Message-Id: <20181021142103.19014-1-clement.deschamps@greensocs.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-11-06 21:35:04 +01:00
Peter Maydell 13399aad4f Error reporting patches for 2018-10-22
-----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJbzcCHAAoJEDhwtADrkYZT3YsP/2qE4HNY/htj3IP6vNJuSaqw
 CLPRTz7zWmUBTE6FqSkvLsq3X2BMFFLeaIPA9EFcbyn2km6qPqBYgg9ElXXvPZBm
 6hDeRIoC8FdRD0Apozd5MGC94/lE47PheDRV8V+4KrGLaaMXEPxMZ0wP4AfdS5pS
 6Pt2xuF7nPu1+OWVxMk0fXadGjGLEuOQQmTh3B21J5RaynQ3gtd6h7XFC/LJyOGG
 LC/6GyPc0h7KU83VnvrRjH/EOpu1wENgrsvWsS0sem8op35Z+i9jU5BfCp4qFkDy
 gCHHUEyEeyexS+W+Tj87eBtK2gfrqQx9ovo8CIsWcUwpKbdD6AMK4FKGsDNMNHab
 Kg5u/M+O8nHCB7DuursF+3mqEbZHb05cfKe6JEtiq49EuORMV5hp4Ap966noSwTw
 UEU0NJNA1p8EdmXVudyyyYR7wpoSSmZpoenA+bJ3nthK8K0KcU4RUGk6ZEbxfJy+
 7ENl+3R2IxmxzgXv/x0tz0uFisaVW1rltTXtMte+ElQsO0qy74iHdfR7JHsmLxj9
 CO/ABMVoYsWq2OJv8pWLrdKpT4v3HQLJdHhknyu0ZcJGDyICqX29ULLEhPrNEZvW
 rxVxAkiemlaqxlUjbrM46CDQQm+w03OCnk7aCYcV4oK+u5+o3mCag705gMPErapZ
 6uOE3fAjiWw43sA31mek
 =kPZX
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2018-10-22' into staging

Error reporting patches for 2018-10-22

# gpg: Signature made Mon 22 Oct 2018 13:20:23 BST
# gpg:                using RSA key 3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-error-2018-10-22: (40 commits)
  error: Drop bogus "use error_setg() instead" admonitions
  vpc: Fail open on bad header checksum
  block: Clean up bdrv_img_create()'s error reporting
  vl: Simplify call of parse_name()
  vl: Fix exit status for -drive format=help
  blockdev: Convert drive_new() to Error
  vl: Assert drive_new() does not fail in default_drive()
  fsdev: Clean up error reporting in qemu_fsdev_add()
  spice: Clean up error reporting in add_channel()
  tpm: Clean up error reporting in tpm_init_tpmdev()
  numa: Clean up error reporting in parse_numa()
  vnc: Clean up error reporting in vnc_init_func()
  ui: Convert vnc_display_init(), init_keyboard_layout() to Error
  ui/keymaps: Fix handling of erroneous include files
  vl: Clean up error reporting in device_init_func()
  vl: Clean up error reporting in parse_fw_cfg()
  vl: Clean up error reporting in mon_init_func()
  vl: Clean up error reporting in machine_set_property()
  vl: Clean up error reporting in chardev_init_func()
  qom: Clean up error reporting in user_creatable_add_opts_foreach()
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-10-23 17:20:23 +01:00
Peter Maydell b312532fd0 * RTC fixes (Artem)
* icount fixes (Artem)
 * rr fixes (Pavel, myself)
 * hotplug cleanup (Igor)
 * SCSI fixes (myself)
 * 4.20-rc1 KVM header update (myself)
 * coalesced PIO support (Peng Hao)
 * HVF fixes (Roman B.)
 * Hyper-V refactoring (Roman K.)
 * Support for Hyper-V IPI (Vitaly)
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQEcBAABAgAGBQJbycRuAAoJEL/70l94x66DGL4H/00Gu/+0dNlpxt6hYVaJ30jX
 vFCsZoglBJ060M8m0C9roTF7zdIgI/X0oxJKWNaxqCDD0GSL5oM1AfG0DCsEBq6X
 ApHYfBOh6mMWuB2qzV9QkK0b2u7+g9J8pQQYfZlU+QNtmUUmbzBxV4h7oqOoedJZ
 nTJrkYzBg88bLDXUAuFrnMhaktqzPvyhdD36vUX5Kc9Hk9R3krtEenc/XKfEJg+o
 n1DX9QeAWgi3MdhkhXSaNSnAu2k2+/qJDmOPk1r63ft5ZfaUKOaVecU06ioiEmrc
 KJd6EYeRvh2eIpbOCGSEVDrieGVBOPvqYg0ryWroxSveoPqJZh5ys9MdIjD+8zg=
 =4XhC
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* RTC fixes (Artem)
* icount fixes (Artem)
* rr fixes (Pavel, myself)
* hotplug cleanup (Igor)
* SCSI fixes (myself)
* 4.20-rc1 KVM header update (myself)
* coalesced PIO support (Peng Hao)
* HVF fixes (Roman B.)
* Hyper-V refactoring (Roman K.)
* Support for Hyper-V IPI (Vitaly)

# gpg: Signature made Fri 19 Oct 2018 12:47:58 BST
# gpg:                using RSA key BFFBD25F78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream: (47 commits)
  replay: pass raw icount value to replay_save_clock
  target/i386: kvm: just return after migrate_add_blocker failed
  hyperv_testdev: add SynIC message and event testmodes
  hyperv: process POST_MESSAGE hypercall
  hyperv: add support for KVM_HYPERV_EVENTFD
  hyperv: process SIGNAL_EVENT hypercall
  hyperv: add synic event flag signaling
  hyperv: add synic message delivery
  hyperv: make overlay pages for SynIC
  hyperv: only add SynIC in compatible configurations
  hyperv: qom-ify SynIC
  hyperv:synic: split capability testing and setting
  i386: add hyperv-stub for CONFIG_HYPERV=n
  default-configs: collect CONFIG_HYPERV* in hyperv.mak
  hyperv: factor out arch-independent API into hw/hyperv
  hyperv: make hyperv_vp_index inline
  hyperv: split hyperv-proto.h into x86 and arch-independent parts
  hyperv: rename kvm_hv_sint_route_set_sint
  hyperv: make HvSintRoute reference-counted
  hyperv: address HvSintRoute by X86CPU pointer
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-10-19 19:01:07 +01:00
Markus Armbruster 0765691e97 cpus hw target: Use warn_report() & friends to report warnings
Calling error_report() in a function that takes an Error ** argument
is suspicious.  Convert a few that are actually warnings to
warn_report().

While there, split a warning consisting of multiple sentences to
conform to conventions spelled out in warn_report()'s contract.

Cc: Alex Bennée <alex.bennee@linaro.org>
Cc: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Fam Zheng <famz@redhat.com>
Cc: Wei Huang <wei@redhat.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20181017082702.5581-5-armbru@redhat.com>
2018-10-19 14:51:34 +02:00
Paolo Bonzini 74c0b816ad replay: pass raw icount value to replay_save_clock
This avoids lock recursion when REPLAY_CLOCK is called inside the
timers spinlock.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-19 13:44:15 +02:00
Emilio G. Cota 72fd2efbbd tcg: distribute tcg_time into TCG contexts
When we implemented per-vCPU TCG contexts, we forgot to also
distribute the tcg_time counter, which has remained as a global
accessed without any serialization, leading to potentially missed
counts.

Fix it by distributing the field over the TCG contexts, embedding
it into TCGProfile with a field called "cpu_exec_time", which is more
descriptive than "tcg_time". Add a function to query this value
directly, and for completeness, fill in the field in
tcg_profile_snapshot, even though its callers do not use it.

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <20181010144853.13005-5-cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-18 18:58:10 -07:00
Alex Bennée 1926ab273b cpus: fix TCG kick timer leak
This is an alternative fix to Marc-André's original patch.

Reported-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20180927171724.30128-1-alex.bennee@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02 19:09:14 +02:00
Pavel Dovgalyuk 0c08185f8f replay: wake up vCPU when replaying
In record/replay icount mode vCPU thread and iothread synchronize
the execution using the checkpoints.
vCPU thread processes the virtual timers and iothread processes all others.
When iothread wants to wake up sleeping vCPU thread, it sends dummy queued
work. Therefore it could be the following sequence of the events in
record mode:
 - IO: sending dummy work
 - IO: processing timers
 - CPU: wakeup
 - CPU: clearing dummy work
 - CPU: processing virtual timers

But due to the races in replay mode the sequence may change:
 - IO: sending dummy work
 - CPU: wakeup
 - CPU: clearing dummy work
 - CPU: sleeping again because nothing to do
 - IO: Processing timers
 - CPU: zzzz

In this case vCPU will not wake up, because dummy work is not to be set up
again.

This patch tries to wake up the vCPU when it sleeps and the icount warp
checkpoint isn't met. It means that vCPU has something to do, because
there are no other reasons of non-matching warp checkpoint.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>

--

v5: improve checking that vCPU is still sleeping
Message-Id: <20180912081945.3228.19776.stgit@pasha-VirtualBox>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02 19:08:51 +02:00
Emilio G. Cota c97595d166 cpus: access .qemu_icount_bias with atomic64
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <20180910232752.31565-11-cota@braap.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02 18:47:55 +02:00
Emilio G. Cota 38adcb6e41 cpus: access .qemu_icount with atomic64
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <20180910232752.31565-10-cota@braap.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02 18:47:55 +02:00
Paolo Bonzini 9b4e6f4966 cpus: take seqlock across qemu_icount updates
Even though writes of qemu_icount can safely race with reads in
qemu_icount_raw, qemu_icount is also read by icount_adjust, which
runs in the I/O thread.  Therefore, writes do needs protection of
the vm_clock_lock; for simplicity the patch protects it with both
seqlock+spinlock, which we already do for hosts that lack 64-bit atomics.

The bug actually predated the introduction of vm_clock_lock;
cpu_update_icount would have needed the BQL before the spinlock was
introduced.

Reported-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02 18:47:55 +02:00
Emilio G. Cota 87a09cdc52 cpus: initialize timers_state.vm_clock_lock
We forgot to initialize the spinlock introduced in 94377115b2
("cpus: protect TimerState writes with a spinlock", 2018-08-23).
Fix it.

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <20180903171831.15446-5-cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02 18:47:55 +02:00
Peter Maydell 9c36281bc5 ppc patch queue 2018-09-07
Here's another pull request for qemu-3.1.  No real theme here, just an
 assortment of various fixes.  Probably the most notable thing is the
 removal of the ppcemb target which has been deprecated for some time
 now.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEdfRlhq5hpmzETofcbDjKyiDZs5IFAluSKPoACgkQbDjKyiDZ
 s5JSpRAAhWvxLM6OoTdhAaPKhlKrIzWexWNI8efJNWfXvHnbHBxs8tk+hnJOZVsU
 m00hfFMKMA0/4JMURrbYsCiyaq+r+Ws8oEbLDVKQdng6LNeUrLq7uC0rv41bW3CC
 1BTqTX16lvhPsg1Sz8mh6IGwCIgRiV8zgvQ4iCc3GCJidI2A+3uLvW5hAndvDdjb
 3lq6drg23LXZ6z/ou7hPynKmV6tFTlxSnB957LCnPGFACZeJKbuoRHPP30IrWwY+
 nOQ1GTvenouGvEKI5gsC13qFWYcoNPPfc7NZFtx1fvxiMpkOj7R5hg9oStT2Ya6u
 MVRwcp/XA2MF+2NnJ8TZOkAV7+1JidhRirsKFjcn1JqftWSxJOKA0weWuNQgdQNY
 lJzyZZejEJCHn0NgOq9ZRjOP4U6iIcSlTurfXoronhw1q7yEBkYkS+JpLToLLsid
 9qwxlBAfUfQ8E1wR8RnM6ATygVp2Z2ToL+70Rc7xzq6/R8kYFSzuhyaI1GUUtPGW
 ZPwp3GRYWJE/xOK3z1YAndrN8FlNxqz3Cov3vtH118aBatWAT+PRVlouOB1/aF3T
 KfV8Kme5KQrMGuj/RDLGLOeQi0e8wqBtVIhsESpHdocC6uo28H5gNXxptyLJPA04
 dJwWvaQf/J7eIuChhuFygiTzMnQyJA1f77jlExpKfxKKQwUpHf4=
 =WnE4
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-3.1-20180907' into staging

ppc patch queue 2018-09-07

Here's another pull request for qemu-3.1.  No real theme here, just an
assortment of various fixes.  Probably the most notable thing is the
removal of the ppcemb target which has been deprecated for some time
now.

# gpg: Signature made Fri 07 Sep 2018 08:30:02 BST
# gpg:                using RSA key 6C38CACA20D9B392
# gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>"
# gpg:                 aka "David Gibson (Red Hat) <dgibson@redhat.com>"
# gpg:                 aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>"
# gpg:                 aka "David Gibson (kernel.org) <dwg@kernel.org>"
# Primary key fingerprint: 75F4 6586 AE61 A66C C44E  87DC 6C38 CACA 20D9 B392

* remotes/dgibson/tags/ppc-for-3.1-20180907:
  target-ppc: Extend HWCAP2 bits for ISA 3.0
  target/ppc/kvm: set vcpu as online/offline
  Fix a deadlock case in the CPU hotplug flow
  spapr: Correct reference count on spapr-cpu-core
  mac_newworld: implement custom FWPathProvider
  uninorth: add ofw-addr property to allow correct fw path generation
  mac_oldworld: implement custom FWPathProvider
  grackle: set device fw_name and address for correct fw path generation
  macio: add addr property to macio IDE object
  macio: add macio bus to help with fw path generation
  macio: move MACIOIDEState type declarations to macio.h
  spapr_pci: fix potential NULL pointer dereference
  spapr: fix leak of rev array
  ppc: Remove deprecated ppcemb target

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-09-24 17:14:10 +01:00
Peter Xu 3ab72385b2 qapi: Drop qapi_event_send_FOO()'s Error ** argument
The generated qapi_event_send_FOO() take an Error ** argument.  They
can't actually fail, because all they do with the argument is passing it
to functions that can't fail: the QObject output visitor, and the
@qmp_emit callback, which is either monitor_qapi_event_queue() or
event_test_emit().

Drop the argument, and pass &error_abort to the QObject output visitor
and @qmp_emit instead.

Suggested-by: Eric Blake <eblake@redhat.com>
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180815133747.25032-4-peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message rewritten, update to qapi-code-gen.txt corrected]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-08-28 18:21:38 +02:00
Thomas Huth a69dc537cc ppc: Remove deprecated ppcemb target
There is no known available OS for ppc around anymore that uses page
sizes below 4k, so it does not make much sense that we keep wasting
our time on building and testing the ppcemb-softmmu target. It has
been deprecated since two releases, and nobody complained, so let's
remove this now.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-08-28 11:31:23 +10:00
Paolo Bonzini f2a4ad6d49 cpus: allow cpu_get_ticks out of BQL
Because of cpu_ticks_prev, we cannot use a seqlock.  But then the conversion
is even easier. :)

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-23 18:46:25 +02:00
Paolo Bonzini 94377115b2 cpus: protect TimerState writes with a spinlock
In the next patch, we will need to write cpu_ticks_offset from any
thread, even outside the BQL.  Currently, it is protected by the BQL
just because cpu_enable_ticks and cpu_disable_ticks happen to hold it,
but the critical sections are well delimited and it's easy to remove
the BQL dependency.

Add a spinlock that matches vm_clock_seqlock, and hold it when writing
to the TimerState.  This also lets us fix cpu_update_icount when 64-bit
atomics are not available.

Fields of TiemrState are reordered to avoid padding.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-23 18:46:25 +02:00
Paolo Bonzini c1ff073cd8 cpus: protect all icount computation with seqlock
Move the icount->ns computation to cpu_get_icount, and make
cpu_get_icount_locked return the raw value.  This makes the
atomic_read__nocheck safe, because it now happens always inside a
seqlock and any torn reads will be retried.  qemu_icount_bias and
icount_time_shift also need to be accessed with atomics.  At the
same time, however, you don't need atomic_read within the writer,
because no concurrent writes are possible.

The fix to vmstate lets us keep the struct nicely packed.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-23 18:46:25 +02:00
Emilio G. Cota 068a5ea02f qom: convert the CPU list to RCU
Iterating over the list without using atomics is undefined behaviour,
since the list can be modified concurrently by other threads (e.g.
every time a new thread is created in user-mode).

Fix it by implementing the CPU list as an RCU QTAILQ. This requires
a little bit of extra work to traverse list in reverse order (see
previous patch), but other than that the conversion is trivial.

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <20180819091335.22863-12-cota@braap.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-23 18:46:25 +02:00
Emilio G. Cota cb764d0665 qsp: track BQL callers explicitly
The BQL is acquired via qemu_mutex_lock_iothread(), which makes
the profiler assign the associated wait time (i.e. most of
BQL wait time) entirely to that function. This loses the original
call site information, which does not help diagnose BQL contention.
Fix it by tracking the callers explicitly.

Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-23 18:46:25 +02:00
Emilio G. Cota f28d0dfdce tcg: fix --disable-tcg build breakage
Fix the --disable-tcg breakage introduced by tb_lock's removal by
relying on the fact that tcg_enabled() is set to 0 at
compile-time under --disable-tcg.

While at it, add further asserts to fix builds that enable both
--disable-tcg and --enable-debug, which were broken even before
tb_lock's removal.

Tested to build x86_64-softmmu and i386-softmmu targets.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-22 18:55:24 +01:00
Anton Nefedov 29cd0403f1 qapi: remove empty flat union branches and types
Flat unions may now have uncovered branches, so it is possible to get rid
of empty types defined for that purpose only.

Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1529311206-76847-3-git-send-email-anton.nefedov@virtuozzo.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-06-22 16:33:46 +02:00
Cédric Le Goater 54961aac19 cpus: tcg: fix never exiting loop on unplug
Commit 9b0605f983 ("cpus: tcg: unregister thread with RCU, fix
exiting of loop on unplug") changed the exit condition of the loop in
the vCPU thread function but forgot to remove the beginning 'while (1)'
statement. The resulting code :

	while (1) {
	...
	} while (!cpu->unplug || cpu_can_run(cpu));

is a sequence of two distinct two while() loops, the first not exiting
in case of an unplug event.

Remove the first while (1) to fix CPU unplug.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20180425131828.15604-1-clg@kaod.org>
Cc: qemu-stable@nongnu.org
Fixes: 9b0605f983
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2018-05-09 00:13:37 +02:00
Markus Armbruster f056158d69 cpus: Fix event order on resume of stopped guest
When resume of a stopped guest immediately runs into block device
errors, the BLOCK_IO_ERROR event is sent before the RESUME event.

Reproducer:

1. Create a scratch image
   $ dd if=/dev/zero of=scratch.img bs=1M count=100

   Size doesn't actually matter.

2. Prepare blkdebug configuration:

   $ cat >blkdebug.conf <<EOF
   [inject-error]
   event = "write_aio"
   errno = "5"
   EOF

   Note that errno 5 is EIO.

3. Run a guest with an additional scratch disk, i.e. with additional
   arguments
   -drive if=none,id=scratch-drive,format=raw,werror=stop,file=blkdebug:blkdebug.conf:scratch.img
   -device virtio-blk-pci,id=scratch,drive=scratch-drive

   The blkdebug part makes all writes to the scratch drive fail with
   EIO.  The werror=stop pauses the guest on write errors.

4. Connect to the QMP socket e.g. like this:
   $ socat UNIX:/your/qmp/socket READLINE,history=$HOME/.qmp_history,prompt='QMP> '

   Issue QMP command 'qmp_capabilities':
   QMP> { "execute": "qmp_capabilities" }

5. Boot the guest.

6. In the guest, write to the scratch disk, e.g. like this:

   # dd if=/dev/zero of=/dev/vdb count=1

   Do double-check the device specified with of= is actually the
   scratch device!

7. Issue QMP command 'cont':
   QMP> { "execute": "cont" }

After step 6, I get a BLOCK_IO_ERROR event followed by a STOP event.  Good.

After step 7, I get BLOCK_IO_ERROR, then RESUME, then STOP.  Not so
good; I'd expect RESUME, then BLOCK_IO_ERROR, then STOP.

The funny event order confuses libvirt: virsh -r domstate DOMAIN
--reason reports "paused (unknown)" rather than "paused (I/O error)".

The culprit is vm_prepare_start().

    /* Ensure that a STOP/RESUME pair of events is emitted if a
     * vmstop request was pending.  The BLOCK_IO_ERROR event, for
     * example, according to documentation is always followed by
     * the STOP event.
     */
    if (runstate_is_running()) {
        qapi_event_send_stop(&error_abort);
        res = -1;
    } else {
        replay_enable_events();
        cpu_enable_ticks();
        runstate_set(RUN_STATE_RUNNING);
        vm_state_notify(1, RUN_STATE_RUNNING);
    }

    /* We are sending this now, but the CPUs will be resumed shortly later */
    qapi_event_send_resume(&error_abort);
    return res;

When resuming a stopped guest, we take the else branch before we get
to sending RESUME.  vm_state_notify() runs virtio_vmstate_change(),
among other things.  This restarts I/O, triggering the BLOCK_IO_ERROR
event.

Reshuffle vm_prepare_start() to send the RESUME event earlier.

Fixes RHBZ 1566153.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180423084518.2426-1-armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-09 00:13:37 +02:00
Laszlo Ersek daa9d2bc6d qapi: discriminate CpuInfoFast on SysEmuTarget, not CpuInfoArch
Add a new field @target (of type @SysEmuTarget) to the output of the
@query-cpus-fast command, which provides more information about the
emulation target than the field @arch (of type @CpuInfoArch). Make @target
the new discriminator for the @CpuInfoFast return structure. Keep @arch
for compatibility.

Cc: "Daniel P. Berrange" <berrange@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180427192852.15013-5-lersek@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-05-04 08:27:53 +02:00
Laszlo Ersek 96054f5639 qapi: fill in CpuInfoFast.arch in query-cpus-fast
* Commit ca230ff33f added the @arch field to @CpuInfoFast, but it failed
  to set the new field in qmp_query_cpus_fast(), when TARGET_S390X was not
  defined. The updated @query-cpus-fast example in "qapi-schema.json"
  showed "arch":"x86" only because qmp_query_cpus_fast() calls g_malloc0()
  to allocate @CpuInfoFast, and the CPU_INFO_ARCH_X86 enum constant is
  generated with value 0.

  All @arch values other than @s390 implied the @CpuInfoOther sub-struct
  for @CpuInfoFast -- at the time of writing the patch --, thus no fields
  other than @arch needed to be set when TARGET_S390X was not defined. Set
  @arch now, by copying the corresponding assignments from
  qmp_query_cpus().

* Commit 25fa194b7b added the @riscv enum constant to @CpuInfoArch (used
  in both @CpuInfo and @CpuInfoFast -- the return types of the @query-cpus
  and @query-cpus-fast commands, respectively), and assigned, in both
  return structures, the @CpuInfoRISCV sub-structure to the new enum
  value.

  However, qmp_query_cpus_fast() would not populate either the @arch field
  or the @CpuInfoRISCV sub-structure, when TARGET_RISCV was defined; only
  qmp_query_cpus() would.

  Assign @CpuInfoOther to the @riscv enum constant in @CpuInfoFast, and
  populate only the @arch field in qmp_query_cpus_fast(). Getting CPU
  state without interrupting KVM is an exceptional thing that only S390X
  does currently. Quoting Cornelia Huck <cohuck@redhat.com>, "s390x is
  exceptional in that it has state in QEMU that is actually interesting
  for upper layers and can be retrieved without performance penalty". See
  also
  <https://www.redhat.com/archives/libvir-list/2018-February/msg00121.html>.

Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Viktor VM Mihajlovski <mihajlov@linux.vnet.ibm.com>
Cc: qemu-stable@nongnu.org
Fixes: ca230ff33f
Fixes: 25fa194b7b
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180427192852.15013-2-lersek@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-05-04 08:27:53 +02:00