A precise style guide and a package-wide overhaul is forthcoming pending
further discussion and consensus. For now, merely avoid obvious errors
that cause Sphinx documentation build problems, using a style loosely
based on PEP 257 and Sphinx Autodoc. It is chosen for interoperability
with our existing Sphinx framework, and because it has loose recognition
in the Pycharm IDE.
See also:
https://www.python.org/dev/peps/pep-0257/https://www.sphinx-doc.org/en/master/usage/restructuredtext/domains.html#info-field-lists
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20201009161558.107041-3-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
In two different places, we are not making a cross-reference to some
resource correctly.
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20201009161558.107041-2-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We had a premature optimization of trying to read as little from the
wire as possible while handling NBD_OPT_SET_META_CONTEXT in phases.
But in reality, we HAVE to read the entire string from the client
before we can get to the next command, and it is easier to just read
it all at once than it is to read it in pieces. And once we do that,
several functions end up no longer performing I/O, so they can drop
length and errp parameters, and just return a bool instead of
modifying through a pointer.
Our iotests still pass; I also checked that libnbd's testsuite (which
covers more corner cases of odd meta context requests) still passes.
There are cases where the sequence of trace messages produced differs
(for example, when no bitmap is exported, a query for "qemu:" now
produces two trace lines instead of one), but trace points are for
debug and have no effect on what the client sees.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200930121105.667049-4-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
[eblake: enhance commit message]
Signed-off-by: Eric Blake <eblake@redhat.com>
The NBD spec is clear that any string sent from the client must not
contain embedded NUL characters. If the client passes "a\0", we
should reject that option request rather than act on "a".
Testing this is not possible with a compliant client, but I was able
to use gdb to coerce libnbd into temporarily behaving as such a
client.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200930121105.667049-3-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Honoring just SIGTERM on Linux is too weak; we also want to handle
other common signals, and do so even on BSD. Why? Because at least
'qemu-nbd -B bitmap' needs a chance to clean up the in-use bit on
bitmaps when the server is shut down via a signal.
See also: http://bugzilla.redhat.com/1883608
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200930121105.667049-2-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
[eblake: apply comment tweak suggested by Vladimir; fix ifdef around
termsig_handler]
Signed-off-by: Eric Blake <eblake@redhat.com>
In a recent commit 12c75e20a2 we've improved
nbd_co_reconnect_loop() to not make drain wait for additional sleep.
Similarly, we shouldn't try to connect, if previous sleep was
interrupted by drain begin, otherwise drain_begin will have to wait for
the whole connection attempt.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200903190301.367620-5-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
reconnect-delay has a design flaw: we handle it in the same loop where
we do connection attempt. So, reconnect-delay may be exceeded by
unpredictable time of connection attempt.
Let's instead use separate timer.
How to reproduce the bug:
1. Create an image on node1:
qemu-img create -f qcow2 xx 100M
2. Start NBD server on node1:
qemu-nbd xx
3. On node2 start qemu-io:
./build/qemu-io --image-opts \
driver=nbd,server.type=inet,server.host=192.168.100.5,server.port=10809,reconnect-delay=15
4. Type 'read 0 512' in qemu-io interface to check that connection
works
Be careful: you should make steps 5-7 in a short time, less than 15
seconds.
5. Kill nbd server on node1
6. Run 'read 0 512' in qemu-io interface again, to be sure that nbd
client goes to reconnect loop.
7. On node1 run the following command
sudo iptables -A INPUT -p tcp --dport 10809 -j DROP
This will make the connect() call of qemu-io at node2 take a long time.
And you'll see that read command in qemu-io will hang for a long time,
more than 15 seconds specified by reconnect-delay parameter. It's the
bug.
8. Don't forget to drop iptables rule on node1:
sudo iptables -D INPUT -p tcp --dport 10809 -j DROP
Important note: Step [5] is necessary to reproduce _this_ bug. If we
miss step [5], the read command (step 6) will hang for a long time and
this commit doesn't help, because there will be not long connect() to
unreachable host, but long sendmsg() to unreachable host, which should
be fixed by enabling and adjusting keep-alive on the socket, which is a
thing for further patch set.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200903190301.367620-4-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Don't use nbd_client_detach_aio_context() driver handler where we want
to finalize the connection. We should directly use
qio_channel_detach_aio_context() in such cases. Driver handler may (and
will) contain another things, unrelated to the qio channel.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200903190301.367620-3-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
We pause reconnect process during drained section. So, if we have some
requests, waiting for reconnect we should cancel them, otherwise they
deadlock the drained section.
How to reproduce:
1. Create an image:
qemu-img create -f qcow2 xx 100M
2. Start NBD server:
qemu-nbd xx
3. Start vm with second nbd disk on node2, like this:
./build/x86_64-softmmu/qemu-system-x86_64 -nodefaults -drive \
file=/work/images/cent7.qcow2 -drive \
driver=nbd,server.type=inet,server.host=192.168.100.5,server.port=10809,reconnect-delay=60 \
-vnc :0 -m 2G -enable-kvm -vga std
4. Access the vm through vnc (or some other way?), and check that NBD
drive works:
dd if=/dev/sdb of=/dev/null bs=1M count=10
- the command should succeed.
5. Now, kill the nbd server, and run dd in the guest again:
dd if=/dev/sdb of=/dev/null bs=1M count=10
Now Qemu is trying to reconnect, and dd-generated requests are waiting
for the connection (they will wait up to 60 seconds (see
reconnect-delay option above) and than fail). But suddenly, vm may
totally hang in the deadlock. You may need to increase reconnect-delay
period to catch the dead-lock.
VM doesn't respond because drain dead-lock happens in cpu thread with
global mutex taken. That's not good thing by itself and is not fixed
by this commit (true way is using iothreads). Still this commit fixes
drain dead-lock itself.
Note: probably, we can instead continue to reconnect during drained
section. To achieve this, we may move negotiation to the connect thread
to make it independent of bs aio context. But expanding drained section
doesn't seem good anyway. So, let's now fix the bug the simplest way.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200903190301.367620-2-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
gcc 10 from Fedora 32 gives me:
Compiling C object libblock.fa.p/nbd_server.c.o
../nbd/server.c: In function ‘nbd_co_client_start’:
../nbd/server.c:625:14: error: ‘namelen’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
625 | rc = nbd_negotiate_send_info(client, NBD_INFO_NAME, namelen, name,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
626 | errp);
| ~~~~~
../nbd/server.c:564:14: note: ‘namelen’ was declared here
564 | uint32_t namelen;
| ^~~~~~~
cc1: all warnings being treated as errors
As I cannot see how this can happen, let uns silence the warning.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-Id: <20200930155859.303148-3-borntraeger@de.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
While I can get the ssh test to fail on my test setup this seems a lot
more stable except when on GitLab. Hopefully we can re-enable both
once the serial timing patches have been added.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20201007160038.26953-23-alex.bennee@linaro.org>
Using "V=1" makes it easier to identify hanging tests, especially
since they are run with -j1. It is already used on Windows builds,
do the same for FreeBSD and macOS.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Ed Maste <emaste@FreeBSD.org>
Message-Id: <20201007140103.711142-1-pbonzini@redhat.com>
Message-Id: <20201007160038.26953-22-alex.bennee@linaro.org>
These authors have some incorrect author email field.
For each of them, there is one commit with the replaced
entry.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Stefan Berger <stefanb@linux.ibm.com>
Acked-by: Erik Smit <erik.lucas.smit@gmail.com>
Message-Id: <20201006160653.2391972-13-f4bug@amsat.org>
Message-Id: <20201007160038.26953-19-alex.bennee@linaro.org>
There is a number of contributors from this domain,
add its own entry to the gitdm domain map.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Roman Kagan <rvkagan@yandex-team.ru>
Message-Id: <20201006160653.2391972-12-f4bug@amsat.org>
Message-Id: <20201007160038.26953-18-alex.bennee@linaro.org>
There is a number of contributions from this domain,
add its own entry to the gitdm domain map.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20201006160653.2391972-11-f4bug@amsat.org>
Message-Id: <20201007160038.26953-17-alex.bennee@linaro.org>
There is a number of contributors from this domain,
add its own entry to the gitdm domain map.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Bruce Rogers <brogers@suse.com>
Message-Id: <20201006160653.2391972-10-f4bug@amsat.org>
Message-Id: <20201007160038.26953-16-alex.bennee@linaro.org>
There is a number of contributions from this domain,
add its own entry to the gitdm domain map.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20201006160653.2391972-8-f4bug@amsat.org>
Message-Id: <20201007160038.26953-14-alex.bennee@linaro.org>
There is a number of contributions from this domain,
add its own entry to the gitdm domain map.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Graeme Gregory <graeme@nuviainc.com>
Message-Id: <20201006160653.2391972-7-f4bug@amsat.org>
Message-Id: <20201007160038.26953-13-alex.bennee@linaro.org>
There is a number of contributors from this domain,
add its own entry to the gitdm domain map.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Erik Kline <ek@google.com>
Message-Id: <20201006160653.2391972-6-f4bug@amsat.org>
Message-Id: <20201007160038.26953-12-alex.bennee@linaro.org>
There is a number of contributors from this domain,
add its own entry to the gitdm domain map.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Jiachen Zhang <zhangjiachen.jaycee@bytedance.com>
Message-Id: <20201006160653.2391972-5-f4bug@amsat.org>
Message-Id: <20201007160038.26953-11-alex.bennee@linaro.org>
There is a number of contributors from this domain,
add its own entry to the gitdm domain map.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Chai Wen <chaiwen@baidu.com>
Message-Id: <20201006160653.2391972-4-f4bug@amsat.org>
Message-Id: <20201007160038.26953-10-alex.bennee@linaro.org>
These individual contributors have a number of contributions,
add them to the 'individual' group map.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Helge Deller <deller@gmx.de>
Acked-by: Stefan Weil <sw@weilnetz.de>
Acked-by: Niek Linnenbank <nieklinnenbank@gmail.com>
Acked-by: David Carlier <devnexen@gmail.com>
Acked-by: Paul Zimmerman <pauldzim@gmail.com>
Acked-by: Volker Rümelin <vr_qemu@t-online.de>
Acked-by: Finn Thain <fthain@telegraphics.com.au>
Message-Id: <20201006160653.2391972-3-f4bug@amsat.org>
Message-Id: <20201007160038.26953-9-alex.bennee@linaro.org>
There is a number of contributions from these academic domains.
Add the entries to the gitdm 'academic' domain map.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Dayeol Lee <dayeol@berkeley.edu>
Acked-by: Fan Yang <Fan_Yang@sjtu.edu.cn>
Acked-by: Xinyu Li <precinct@mail.ustc.edu.cn>
Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Message-Id: <20201006160653.2391972-2-f4bug@amsat.org>
Message-Id: <20201007160038.26953-8-alex.bennee@linaro.org>
genisoimage is needed for running the tests/qtest/cdrom-test qtest.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20201006174347.152040-1-thuth@redhat.com>
Message-Id: <20201007160038.26953-7-alex.bennee@linaro.org>
The following target are add back:
i386-softmmu,arm-softmmu,ppc-softmmu,mips-softmmu
Signed-off-by: Yonggang Luo <luoyonggang@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20201007145300.1197-3-luoyonggang@gmail.com>
Message-Id: <20201007160038.26953-6-alex.bennee@linaro.org>
Use cache of cirrus caching msys2
The install of msys2 are refer to https://github.com/msys2/setup-msys2
The first time install msys2 would be time consuming, so increase timeout_in to 90m
according to https://cirrus-ci.org/faq/#instance-timed-out
Apply patch of https://lists.gnu.org/archive/html/qemu-devel/2020-10/msg00072.html
[AJB: renamed printenv_script to setup_script]
Signed-off-by: Yonggang Luo <luoyonggang@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20201007145300.1197-2-luoyonggang@gmail.com>
Message-Id: <20201007160038.26953-5-alex.bennee@linaro.org>
A recent change to weak reset handling broke replay due to the use of
aio_bh_schedule_oneshot instead of the replay aware
replay_bh_schedule_oneshot_event.
Fixes: 55adb3c456 ("ide: cancel pending callbacks on SRST")
Suggested-by: Pavel Dovgalyuk <pavel.dovgalyuk@ispras.ru>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: John Snow <jsnow@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>
Message-Id: <20201007160038.26953-4-alex.bennee@linaro.org>
In commit 102ca9667d we set "start-powered-off" on all vCPUs
included in the CPS (Coherent Processing System) but forgot to
start the vCPUS on when they are powered on in the CPC (Cluster
Power Controller).
This fixes the following tests:
$ avocado run tests/acceptance/machine_mips_malta.py
(1/3) test_mips_malta_i6400_framebuffer_logo_1core: PASS (3.67 s)
(2/3) test_mips_malta_i6400_framebuffer_logo_7cores: INTERRUPTED: Test interrupted by SIGTERM (30.22 s)
(3/3) test_mips_malta_i6400_framebuffer_logo_8cores: INTERRUPTED: Test interrupted by SIGTERM (30.25 s)
RESULTS : PASS 1 | ERROR 0 | FAIL 0 | SKIP 0 | WARN 0 | INTERRUPT 2 | CANCEL 0
Fixes: 102ca9667d ("mips/cps: Use start-powered-off CPUState property")
Reported-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20201007113942.2523866-1-f4bug@amsat.org>
Message-Id: <20201007160038.26953-3-alex.bennee@linaro.org>
Because most files in QEMU are grouped into static libraries, Meson conservatively
compiles them with -fPIC. This is overkill and produces slowdowns up to 20% on
some TCG tests.
As a stopgap measure, use the b_staticpic option to limit the slowdown to
--enable-pie. https://github.com/mesonbuild/meson/pull/7760 will allow
us to use b_staticpic=false and let Meson do the right thing.
Reported-by: Ahmed Karaman <ahmedkrmn@outlook.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200924092314.1722645-57-pbonzini@redhat.com>
Message-Id: <20201007160038.26953-2-alex.bennee@linaro.org>
Here's the next set of ppc related patches for qemu-5.2. There are
two main things here:
* Cleanups to error handling in spapr from Greg Kurz
* Improvements to NUMA handling for spapr from Daniel Barboza
There are also a handful of other bugfixes.
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Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-5.2-20201009' into staging
ppc patch queue 2020-10-09
Here's the next set of ppc related patches for qemu-5.2. There are
two main things here:
* Cleanups to error handling in spapr from Greg Kurz
* Improvements to NUMA handling for spapr from Daniel Barboza
There are also a handful of other bugfixes.
# gpg: Signature made Fri 09 Oct 2020 07:02:29 BST
# gpg: using RSA key 75F46586AE61A66CC44E87DC6C38CACA20D9B392
# gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>" [full]
# gpg: aka "David Gibson (Red Hat) <dgibson@redhat.com>" [full]
# gpg: aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>" [full]
# gpg: aka "David Gibson (kernel.org) <dwg@kernel.org>" [unknown]
# Primary key fingerprint: 75F4 6586 AE61 A66C C44E 87DC 6C38 CACA 20D9 B392
* remotes/dgibson/tags/ppc-for-5.2-20201009:
specs/ppc-spapr-numa: update with new NUMA support
spapr_numa: consider user input when defining associativity
spapr_numa: change reference-points and maxdomain settings
spapr_numa: forbid asymmetrical NUMA setups
spapr: add spapr_machine_using_legacy_numa() helper
ppc/pnv: Increase max firmware size
spapr: Add a return value to spapr_check_pagesize()
spapr: Add a return value to spapr_nvdimm_validate()
spapr: Simplify error handling in spapr_cpu_core_realize()
spapr: Add a return value to spapr_set_vcpu_id()
spapr: Simplify error handling in prop_get_fdt()
spapr: Add a return value to spapr_drc_attach()
spapr: Simplify error handling in spapr_vio_busdev_realize()
spapr: Simplify error handling in do_client_architecture_support()
spapr: Get rid of cas_check_pvr() error reporting
spapr: Simplify error handling in callers of ppc_set_compat()
ppc: Fix return value in cpu_post_load() error path
ppc: Add a return value to ppc_set_compat() and ppc_set_compat_all()
spapr: Fix error leak in spapr_realize_vcpu()
spapr: Handle HPT allocation failure in nested guest
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
block_resize performs some I/O that could potentially take quite some
time, so use it as an example for the new 'coroutine': true annotation
in the QAPI schema.
bdrv_truncate() requires that we're already in the right AioContext for
the BlockDriverState if called in coroutine context. So instead of just
taking the AioContext lock, move the QMP handler coroutine to the
context.
Call blk_unref() only after switching back because blk_unref() may only
be called in the main thread.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201005155855.256490-15-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Inside of coroutine context, we can't directly use aio_context_acquire()
for the AioContext of a block node because we already own the lock of
the current AioContext and we need to avoid double locking to prevent
deadlocks.
This provides helper functions to lock the AioContext of a node only if
it's not the same as the current AioContext.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201005155855.256490-14-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Add a pair of functions to temporarily move the current coroutine to the
AioContext of a given BlockDriverState.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201005155855.256490-13-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Add a function that can be used to move the currently running coroutine
to a different AioContext (and therefore potentially a different
thread).
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20201005155855.256490-12-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Often, QMP command handlers are not only called to handle QMP commands,
but also from a corresponding HMP command handler. In order to give them
a consistent environment, optionally run HMP command handlers in a
coroutine, too.
The implementation is a lot simpler than in QMP because for HMP, we
still block the VM while the coroutine is running.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20201005155855.256490-11-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This moves the QMP dispatcher to a coroutine and runs all QMP command
handlers that declare 'coroutine': true in coroutine context so they
can avoid blocking the main loop while doing I/O or waiting for other
events.
For commands that are not declared safe to run in a coroutine, the
dispatcher drops out of coroutine context by calling the QMP command
handler from a bottom half.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201005155855.256490-10-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This patch adds a new 'coroutine' flag to QMP command definitions that
tells the QMP dispatcher that the command handler is safe to be run in a
coroutine.
The documentation of the new flag pretends that this flag is already
used as intended, which it isn't yet after this patch. We'll implement
this in another patch in this series.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201005155855.256490-9-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This way, a monitor command handler will still be able to access the
current monitor, but when it yields, all other code code will correctly
get NULL from monitor_cur().
This uses a hash table to map the coroutine pointer to the current
monitor of that coroutine. Outside of coroutine context, we associate
the current monitor with the leader coroutine of the current thread.
Approaches to implement some form of coroutine local storage directly in
the coroutine core code have been considered and discarded because they
didn't end up being much more generic than the hash table and their
performance impact on coroutines not using coroutine local storage was
unclear. As the block layer uses a coroutine per I/O request, this is a
fast path and we have to be careful. It's safest to just stay out of
this path with code only used by the monitor.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201005155855.256490-8-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The correct way to set the current monitor for a coroutine handler will
be different than for a blocking handler, so monitor_set_cur() needs to
be called in qmp_dispatch().
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201005155855.256490-7-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
monitor_qmp_dispatch() is never supposed to be called in the context of
another monitor, so assert that monitor_cur() is NULL instead of saving
and restoring it.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201005155855.256490-6-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The current monitor is updated relatively early in the command handling
code even though only the command handler actually needs it.
The current monitor will become coroutine-local later, so we can only
update it when we know in which coroutine the command will be exectued.
Move it to handle_hmp_command() where this information will be
available.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201005155855.256490-5-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
cur_mon really needs to be coroutine-local as soon as we move monitor
command handlers to coroutines and let them yield. As a first step, just
remove all direct accesses to cur_mon so that we can implement this in
the getter function later.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201005155855.256490-4-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
John Snow
Peter Maydell
Eric Blake
Vladimir Sementsov-Ogievskiy
Christian Borntraeger
Alex Bennée
Paolo Bonzini
Yonggang Luo
Philippe Mathieu-Daudé
Thomas Huth
Markus Armbruster
Kevin Wolf