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  1. 07 11月, 2018 1 次提交
  3. 19 10月, 2018 3 次提交
  5. 03 10月, 2018 6 次提交
  7. 29 8月, 2018 1 次提交
  9. 28 8月, 2018 1 次提交
  11. 24 8月, 2018 5 次提交
    • P
      cpus: allow cpu_get_ticks out of BQL · f2a4ad6d
      由 Paolo Bonzini 提交于 
      Because of cpu_ticks_prev, we cannot use a seqlock.  But then the conversion
is even easier. :)
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      f2a4ad6d
    • P
      cpus: protect TimerState writes with a spinlock · 94377115
      由 Paolo Bonzini 提交于 
      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: NPaolo Bonzini <pbonzini@redhat.com>
      94377115
    • P
      cpus: protect all icount computation with seqlock · c1ff073c
      由 Paolo Bonzini 提交于 
      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: NPaolo Bonzini <pbonzini@redhat.com>
      c1ff073c
    • E
      qom: convert the CPU list to RCU · 068a5ea0
      由 Emilio G. Cota 提交于 
      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: NEmilio G. Cota <cota@braap.org>
Message-Id: <20180819091335.22863-12-cota@braap.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      068a5ea0
    • E
      qsp: track BQL callers explicitly · cb764d06
      由 Emilio G. Cota 提交于 
      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: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      cb764d06
  13. 23 6月, 2018 1 次提交
  15. 22 6月, 2018 1 次提交
  17. 09 5月, 2018 2 次提交
    • C
      cpus: tcg: fix never exiting loop on unplug · 54961aac
      由 Cédric Le Goater 提交于 
      Commit 9b0605f9 ("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: NCédric Le Goater <clg@kaod.org>
Message-Id: <20180425131828.15604-1-clg@kaod.org>
Cc: qemu-stable@nongnu.org
Fixes: 9b0605f9Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NCédric Le Goater <clg@kaod.org>
      54961aac
    • M
      cpus: Fix event order on resume of stopped guest · f056158d
      由 Markus Armbruster 提交于 
      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: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20180423084518.2426-1-armbru@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      f056158d
  19. 04 5月, 2018 2 次提交
    • L
      qapi: discriminate CpuInfoFast on SysEmuTarget, not CpuInfoArch · daa9d2bc
      由 Laszlo Ersek 提交于 
      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: NLaszlo Ersek <lersek@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20180427192852.15013-5-lersek@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
      daa9d2bc
    • L
      qapi: fill in CpuInfoFast.arch in query-cpus-fast · 96054f56
      由 Laszlo Ersek 提交于 
      * Commit ca230ff3 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 25fa194b 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: ca230ff3
Fixes: 25fa194bSigned-off-by: NLaszlo Ersek <lersek@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NCornelia Huck <cohuck@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20180427192852.15013-2-lersek@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
      96054f56
  21. 10 4月, 2018 1 次提交
  23. 13 3月, 2018 1 次提交
  25. 09 3月, 2018 1 次提交
    • S
      vl: introduce vm_shutdown() · 4486e89c
      由 Stefan Hajnoczi 提交于 
      Commit 00d09fdb ("vl: pause vcpus before
stopping iothreads") and commit dce8921b
("iothread: Stop threads before main() quits") tried to work around the
fact that emulation was still active during termination by stopping
iothreads.  They suffer from race conditions:
1. virtio_scsi_handle_cmd_vq() racing with iothread_stop_all() hits the
   virtio_scsi_ctx_check() assertion failure because the BDS AioContext
   has been modified by iothread_stop_all().
2. Guest vq kick racing with main loop termination leaves a readable
   ioeventfd that is handled by the next aio_poll() when external
   clients are enabled again, resulting in unwanted emulation activity.

This patch obsoletes those commits by fully disabling emulation activity
when vcpus are stopped.

Use the new vm_shutdown() function instead of pause_all_vcpus() so that
vm change state handlers are invoked too.  Virtio devices will now stop
their ioeventfds, preventing further emulation activity after vm_stop().

Note that vm_stop(RUN_STATE_SHUTDOWN) cannot be used because it emits a
QMP STOP event that may affect existing clients.

It is no longer necessary to call replay_disable_events() directly since
vm_shutdown() does so already.

Drop iothread_stop_all() since it is no longer used.

Cc: Fam Zheng <famz@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 20180307144205.20619-5-stefanha@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      4486e89c
  27. 07 3月, 2018 1 次提交
  29. 06 3月, 2018 3 次提交
  31. 03 3月, 2018 2 次提交
    • M
      qapi: Empty out qapi-schema.json · 112ed241
      由 Markus Armbruster 提交于 
      The previous commit improved compile time by including less of the
generated QAPI headers.  This is impossible for stuff defined directly
in qapi-schema.json, because that ends up in headers that that pull in
everything.

Move everything but include directives from qapi-schema.json to new
sub-module qapi/misc.json, then include just the "misc" shard where
possible.

It's possible everywhere, except:

* monitor.c needs qmp-command.h to get qmp_init_marshal()

* monitor.c, ui/vnc.c and the generated qapi-event-FOO.c need
  qapi-event.h to get enum QAPIEvent

Perhaps we'll get rid of those some other day.

Adding a type to qapi/migration.json now recompiles some 120 instead
of 2300 out of 5100 objects.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-25-armbru@redhat.com>
[eblake: rebase to master]
Signed-off-by: NEric Blake <eblake@redhat.com>
      112ed241
    • M
      Include less of the generated modular QAPI headers · 9af23989
      由 Markus Armbruster 提交于 
      In my "build everything" tree, a change to the types in
qapi-schema.json triggers a recompile of about 4800 out of 5100
objects.

The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h,
qapi-types.h.  Each of these headers still includes all its shards.
Reduce compile time by including just the shards we actually need.

To illustrate the benefits: adding a type to qapi/migration.json now
recompiles some 2300 instead of 4800 objects.  The next commit will
improve it further.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-24-armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
[eblake: rebase to master]
Signed-off-by: NEric Blake <eblake@redhat.com>
      9af23989
  33. 26 2月, 2018 3 次提交
  35. 09 2月, 2018 2 次提交
  37. 07 2月, 2018 3 次提交