aio_worker() doesn't add anything interesting, it's only a useless
indirection. Call the handler function directly instead.
As we know that this handler function is only called from coroutine
context and the coroutine stays around until the worker thread finishes,
we can keep RawPosixAIOData on the stack.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Getting the thread pool of the AioContext of a block node and scheduling
some work in it is an operation that is already done twice, and we'll
get more instances. Factor it out into a separate function.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
RawPosixAIOData contains a lot of fields for several separate operations
that are to be processed in a worker thread and that need different
parameters. The struct is currently rather unorganised, with unions that
cover some, but not all operations, and even one #define for field names
instead of a union.
Clean this up to have some common fields and a single union. As a side
effect, on x86_64 the struct shrinks from 72 to 48 bytes.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Do decompression in threads, like it is already done for compression.
This improves asynchronous compressed reads performance.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Allocate buffers locally and release qcow2 lock. Than, reads inside
qcow2_co_preadv_compressed may be done in parallel, however all
decompression is still done synchronously. Let's improve it in the
following commit.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Get rid of it here too.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
- make it look more like a pair of qcow2_compress - rename the function
and its parameters
- drop extra out_len variable, check filling of output buffer by strm
structure itself
- fix code style
- add some documentation
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Compression is done in threads in qcow2.c. We want to do decompression
in the same way, so, firstly, move it to the same file.
The only change is braces around if-body in decompress_buffer, to
satisfy checkpatch.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Give explicit size both for source and destination buffers, to make it
similar with decompression path and than cleanly reuse parameter
structure for decompression threads.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Use appropriate macro, corresponding to deflateInit2 spec.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
After commit f8d59dfb40
"block/backup: fix fleecing scheme: use serialized writes" fleecing
(specifically reading from backup target, when backup source is in
backing chain of backup target) is safe, because all backup-job writes
to target are serialized. Therefore we don't need additional
synchronization for these reads.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This change is better to understand what kind of block type is being
handled by the code. Using a syntax similar to the DMG documentation is
easier than tracking all hex values assigned to a block type.
Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit includes the support to new module dmg-lzfse into dmg block
driver. It includes the support for block type ULFO (0x80000007).
Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit includes the support to lzfse opensource library. With this
library dmg block driver can decompress images with this type of
compression inside.
Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
QEMU dmg support includes zlib and bzip2, but it does not contains lzfse
support. This commit adds the source file to extend compression support
for new DMGs.
Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
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Merge remote-tracking branch 'remotes/stefanberger/tags/pull-tpm-2018-12-04-1' into staging
Merge tpm 2018/12/04 v1
# gpg: Signature made Tue 04 Dec 2018 15:25:52 GMT
# gpg: using RSA key 75AD65802A0B4211
# gpg: Good signature from "Stefan Berger <stefanb@linux.vnet.ibm.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: B818 B9CA DF90 89C2 D5CE C66B 75AD 6580 2A0B 4211
* remotes/stefanberger/tags/pull-tpm-2018-12-04-1:
tpm: Make sure the locality received from backend is valid
tpm: Make sure new locality passed to tpm_tis_prep_abort() is valid
tpm: Remove unused locty parameter from tpm_tis_abort()
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The two thing that should be handled are cipher and ivgen. For ivgen
the solution is just mutex, as iv calculations should not be long in
comparison with encryption/decryption. And for cipher let's just keep
per-thread ciphers.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Introduce QCryptoBlock-based functions and use them where possible.
This is needed to implement thread-safe encrypt/decrypt operations.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Rename qcrypto_block_*crypt_helper to qcrypto_block_cipher_*crypt_helper,
as it's not about QCryptoBlock. This is needed to introduce
qcrypto_block_*crypt_helper in the next commit, which will have
QCryptoBlock pointer and than will be able to use additional fields of
it, which in turn will be used to implement thread-safe QCryptoBlock
operations.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
qcrypto_block_encrypt_helper and qcrypto_block_decrypt_helper are
almost identical, let's reduce code duplication and simplify further
improvements.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Free block->cipher and block->ivgen on error path.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The values specified in the documentation don't match the actual
defaults set in qcrypto_block_luks_create().
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This changes two lines in simple.c that end with a comma, and replaces them
with a semi-colon.
Signed-off-by: Larry Dewey <ldewey@suse.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20181127190849.10558-1-ldewey@suse.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Currently the log backend prints the process id of QEMU at the start
of each output line, but since threads share the same PID there is no
clear distinction between their outputs.
Having the thread id present in the log makes it easier to see when
output comes from different threads. E.g.:
12423@1538597569.672527:qemu_mutex_lock waiting on mutex 0x1103ee60 (/root/qemu/util/main-loop.c:236)
...
12430@1538597569.503928:qemu_mutex_unlock released mutex 0x1103ee60 (/root/qemu/cpus.c:1238)
12431@1538597569.503937:qemu_mutex_locked taken mutex 0x1103ee60 (/root/qemu/cpus.c:1257)
^here
In the above, 12423 is the main process id and 12430 & 12431 are the
two vcpu threads.
(qemu) info cpus
* CPU #0: thread_id=12430
CPU #1: thread_id=12431
Suggested-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Taking the address of a field in a packed struct is a bad idea, because
it might not be actually aligned enough for that pointer type (and
thus cause a crash on dereference on some host architectures). Newer
versions of clang warn about this. Avoid the bug by not using the
"modify in place" byte swapping functions.
Patch produced with scripts/coccinelle/inplace-byteswaps.cocci
(with a couple of long lines manually wrapped).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20181210120436.30522-1-peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
vfio-ap devices do not pin any pages in the host. Therefore, they
are compatible with memory ballooning.
Flag them as compatible, so both vfio-ap and a balloon can be
used simultaneously.
Cc: qemu-stable@nongnu.org
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Just like on other architectures, we should stop the clock while the guest
is not running. This is already properly done for TCG. Right now, doing an
offline migration (stop, migrate, cont) can easily trigger stalls in the
guest.
Even doing a
(hmp) stop
... wait 2 minutes ...
(hmp) cont
will already trigger stalls.
So whenever the guest stops, backup the KVM TOD. When continuing to run
the guest, restore the KVM TOD.
One special case is starting a simple VM: Reading the TOD from KVM to
stop it right away until the guest is actually started means that the
time of any simple VM will already differ to the host time. We can
simply leave the TOD running and the guest won't be able to recognize
it.
For migration, we actually want to keep the TOD stopped until really
starting the guest. To be able to catch most errors, we should however
try to set the TOD in addition to simply storing it. So we can still
catch basic migration problems.
If anything goes wrong while backing up/restoring the TOD, we have to
ignore it (but print a warning). This is then basically a fallback to
old behavior (TOD remains running).
I tested this very basically with an initrd:
1. Start a simple VM. Observed that the TOD is kept running. Old
behavior.
2. Ordinary live migration. Observed that the TOD is temporarily
stopped on the destination when setting the new value and
correctly started when finally starting the guest.
3. Offline live migration. (stop, migrate, cont). Observed that the
TOD will be stopped on the source with the "stop" command. On the
destination, the TOD is temporarily stopped when setting the new
value and correctly started when finally starting the guest via
"cont".
4. Simple stop/cont correctly stops/starts the TOD. (multiple stops
or conts in a row have no effect, so works as expected)
In the future, we might want to send the guest a special kind of time sync
interrupt under some conditions, so it can synchronize its tod to the
host tod. This is interesting for migration scenarios but also when we
get time sync interrupts ourselves. This however will most probably have
to be handled in KVM (e.g. when the tods differ too much) and is not
desired e.g. when debugging the guest (single stepping should not
result in permanent time syncs). I consider something like that an add-on
on top of this basic "don't break the guest" handling.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181130094957.4121-1-david@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Halil does more work in this area than I do right now. Lets add Halil.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-Id: <20181204133802.100998-1-borntraeger@de.ibm.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
I fail to see why this is useful as we require MSIX always and
completely fail adding a device.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181105110313.29312-2-david@redhat.com>
Fixes: 4f6482bfe3
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Collin Walling <walling@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Straightforward test just to let the test-qmp-cmds be complete.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20181009062718.1914-6-peterx@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This reverts commit ddee57e017.
Meanwhile, revert one line from fa198ad9bd to make sure
qtest_init_without_qmp_handshake() will only pass in one parameter.
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20181009062718.1914-5-peterx@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Out-of-band command execution was introduced in commit cf869d5317.
Unfortunately, we ran into a regression, and had to turn it into an
experimental option for 2.12 (commit be933ffc23).
http://lists.gnu.org/archive/html/qemu-devel/2018-03/msg06231.html
The regression has since been fixed (commit 951702f39c "monitor: bind
dispatch bh to iohandler context"). A thorough re-review of OOB
commands led to a few more issues, which have also been addressed.
This patch partly reverts be933ffc23 (monitor: new parameter "x-oob"),
and makes QMP monitors again offer capability "oob" whenever they can
provide it, i.e. when the monitor's character device is capable of
running in an I/O thread.
Some trivial touch-up in the test code is required to make sure qmp-test
won't break.
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20181009062718.1914-4-peterx@redhat.com>
[Conflict with "monitor: check if chardev can switch gcontext for OOB"
resolved, commit message updated]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The initial value of nalloc is -1, but not 1.
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-id: 1541479952-32355-1-git-send-email-dongli.zhang@oracle.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
In virtio_blk_handle_request(), in_iov is used for input header while iov
is used for output header. Rename iov to out_iov to pair output header's
name with in_iov to avoid confusing people when reading source code.
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Message-id: 1541520556-8334-1-git-send-email-dongli.zhang@oracle.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When a QMP client sends in-band commands more quickly that we can
process them, we can either queue them without limit (QUEUE), drop
commands when the queue is full (DROP), or suspend receiving commands
when the queue is full (SUSPEND). None of them is ideal:
* QUEUE lets a misbehaving client make QEMU eat memory without bounds.
Not such a hot idea.
* With DROP, the client has to cope with dropped in-band commands. To
inform the client, we send a COMMAND_DROPPED event then. The event is
flawed by design in two ways: it's ambiguous (see commit d621cfe0a1),
and it brings back the "eat memory without bounds" problem.
* With SUSPEND, the client has to manage the flow of in-band commands to
keep the monitor available for out-of-band commands.
We currently DROP. Switch to SUSPEND.
Managing the flow of in-band commands to keep the monitor available for
out-of-band commands isn't really hard: just count the number of
"outstanding" in-band commands (commands sent minus replies received),
and if it exceeds the limit, hold back additional ones until it drops
below the limit again.
Note that we need to be careful pairing the suspend with a resume, or
else the monitor will hang, possibly forever. And here since we need to
make sure both:
(1) popping request from the req queue, and
(2) reading length of the req queue
will be in the same critical section, we let the pop function take the
corresponding queue lock when there is a request, then we release the
lock from the caller.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20181009062718.1914-2-peterx@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
When a monitor is connected to a Spice chardev, the monitor cleanup
can dead-lock:
#0 0x00007f43446637fd in __lll_lock_wait () at /lib64/libpthread.so.0
#1 0x00007f434465ccf4 in pthread_mutex_lock () at /lib64/libpthread.so.0
#2 0x0000556dd79f22ba in qemu_mutex_lock_impl (mutex=0x556dd81c9220 <monitor_lock>, file=0x556dd7ae3648 "/home/elmarco/src/qq/monitor.c", line=645) at /home/elmarco/src/qq/util/qemu-thread-posix.c:66
#3 0x0000556dd7431bd5 in monitor_qapi_event_queue (event=QAPI_EVENT_SPICE_DISCONNECTED, qdict=0x556dd9abc850, errp=0x7fffb7bbddd8) at /home/elmarco/src/qq/monitor.c:645
#4 0x0000556dd79d476b in qapi_event_send_spice_disconnected (server=0x556dd98ee760, client=0x556ddaaa8560, errp=0x556dd82180d0 <error_abort>) at qapi/qapi-events-ui.c:149
#5 0x0000556dd7870fc1 in channel_event (event=3, info=0x556ddad1b590) at /home/elmarco/src/qq/ui/spice-core.c:235
#6 0x00007f434560a6bb in reds_handle_channel_event (reds=<optimized out>, event=3, info=0x556ddad1b590) at reds.c:316
#7 0x00007f43455f393b in main_dispatcher_self_handle_channel_event (info=0x556ddad1b590, event=3, self=0x556dd9a7d8c0) at main-dispatcher.c:197
#8 0x00007f43455f393b in main_dispatcher_channel_event (self=0x556dd9a7d8c0, event=event@entry=3, info=0x556ddad1b590) at main-dispatcher.c:197
#9 0x00007f4345612833 in red_stream_push_channel_event (s=s@entry=0x556ddae2ef40, event=event@entry=3) at red-stream.c:414
#10 0x00007f434561286b in red_stream_free (s=0x556ddae2ef40) at red-stream.c:388
#11 0x00007f43455f9ddc in red_channel_client_finalize (object=0x556dd9bb21a0) at red-channel-client.c:347
#12 0x00007f434b5f9fb9 in g_object_unref () at /lib64/libgobject-2.0.so.0
#13 0x00007f43455fc212 in red_channel_client_push (rcc=0x556dd9bb21a0) at red-channel-client.c:1341
#14 0x0000556dd76081ba in spice_port_set_fe_open (chr=0x556dd9925e20, fe_open=0) at /home/elmarco/src/qq/chardev/spice.c:241
#15 0x0000556dd796d74a in qemu_chr_fe_set_open (be=0x556dd9a37c00, fe_open=0) at /home/elmarco/src/qq/chardev/char-fe.c:340
#16 0x0000556dd796d4d9 in qemu_chr_fe_set_handlers (b=0x556dd9a37c00, fd_can_read=0x0, fd_read=0x0, fd_event=0x0, be_change=0x0, opaque=0x0, context=0x0, set_open=true) at /home/elmarco/src/qq/chardev/char-fe.c:280
#17 0x0000556dd796d359 in qemu_chr_fe_deinit (b=0x556dd9a37c00, del=false) at /home/elmarco/src/qq/chardev/char-fe.c:233
#18 0x0000556dd7432240 in monitor_data_destroy (mon=0x556dd9a37c00) at /home/elmarco/src/qq/monitor.c:786
#19 0x0000556dd743b968 in monitor_cleanup () at /home/elmarco/src/qq/monitor.c:4683
#20 0x0000556dd75ce776 in main (argc=3, argv=0x7fffb7bbe458, envp=0x7fffb7bbe478) at /home/elmarco/src/qq/vl.c:4660
Because spice code tries to emit a "disconnected" signal on the
monitors. Fix this dead-lock by releasing the monitor lock for
flush/destroy.
monitor_lock protects mon_list, monitor_qapi_event_state and
monitor_destroyed. monitor_flush() and monitor_data_destroy() don't
access any of those variables.
monitor_cleanup()'s loop is safe because it uses
QTAILQ_FOREACH_SAFE(), and no further monitor can be added after
calling monitor_cleanup() thanks to monitor_destroyed check in
monitor_list_append().
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181205203737.9011-8-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
monitor_cleanup() is one of the last things main() calls before it
returns. In the following patch, monitor_cleanup() will release the
monitor_lock during flushing. There may be pending commands to insert
new monitors, which would modify the mon_list during iteration, and
the clean-up could thus miss those new insertions.
Add a monitor_destroyed global to check if monitor_cleanup() has been
already called. In this case, don't insert the new monitor in the
list, but free it instead. A cleaner solution would involve the main
thread telling other threads to terminate, waiting for their
termination.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181205203737.9011-7-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
COLO uses a worker context (iothread) to drive the chardev. All
backends are not able to switch the context, let's report an error in
this case.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181205203737.9011-6-marcandre.lureau@redhat.com>
Reviewed-by: Li Zhijian <lizhiian@cn.fujitsu.com>
Reviewed-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Not all backends are able to switch gcontext. Those backends cannot
drive a OOB monitor (the monitor would then be blocking on main
thread).
For example, ringbuf, spice, or more esoteric input chardevs like
braille or MUX.
We already forbid MUX because not all frontends are ready to run outside
main loop. Replace that by a context-switching feature check.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181205203737.9011-5-marcandre.lureau@redhat.com>
[Error condition simplified, commit message adjusted accordingly]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
QEMU_CHAR_FEATURE_GCONTEXT declares the character device can switch
GMainContext.
Assert we don't switch context when the character device doesn't
provide this feature. Character device users must not violate this
restriction. In particular, user configurations that violate them
must be rejected.
Existing frontend that rely on context switching would now assert() if
the backend doesn't allow it (instead of silently producing undesired
events in the default context). Following patches improve the
situation by reporting an error earlier instead, on the frontend side.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181205203737.9011-4-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Chardev backends may not handle safely IO events from concurrent
threads (may not handle I/O events from concurrent threads safely,
only the write path is since commit >
9005b2a758). Better to wake up the
chardev from the monitor IO thread if it's being used as the chardev
context.
Unify code paths by using a BH in all cases.
Drop the now redundant aio_notify() call.
Clean up control flow not to rely on mon->use_io_thread implying
monitor_is_qmp(mon).
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181205203737.9011-3-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The function were not named with "mon_iothread", or following the AIO
vs GMainContext distinction. Inline them instead.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181205203737.9011-2-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Kevin Wolf