Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2021-06-15-v2' into staging

nbd patches for 2021-06-15

- bug fixes in coroutine aio context handling
- rework NBD client connection logic t

Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2021-06-15-v2' into staging

nbd patches for 2021-06-15

- bug fixes in coroutine aio context handling
- rework NBD client connection logic to perform more work in coroutine

# gpg: Signature made Fri 18 Jun 2021 18:29:39 BST
# gpg: using RSA key 71C2CC22B1C4602927D2F3AAA7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>" [full]
# gpg: aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>" [full]
# gpg: aka "[jpeg image of size 6874]" [full]
# Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2 F3AA A7A1 6B4A 2527 436A

* remotes/ericb/tags/pull-nbd-2021-06-15-v2: (34 commits)
block/nbd: safer transition to receiving request
block/nbd: add nbd_client_connected() helper
block/nbd: reuse nbd_co_do_establish_connection() in nbd_open()
nbd/client-connection: add option for non-blocking connection attempt
block/nbd: split nbd_co_do_establish_connection out of nbd_reconnect_attempt
block-coroutine-wrapper: allow non bdrv_ prefix
nbd/client-connection: return only one io channel
block/nbd: drop BDRVNBDState::sioc
block/nbd: don't touch s->sioc in nbd_teardown_connection()
block/nbd: use negotiation of NBDClientConnection
block/nbd: split nbd_handle_updated_info out of nbd_client_handshake()
nbd/client-connection: shutdown connection on release
nbd/client-connection: implement connection retry
nbd/client-connection: add possibility of negotiation
nbd/client-connection: use QEMU_LOCK_GUARD
nbd: move connection code from block/nbd to nbd/client-connection
block/nbd: introduce nbd_client_connection_release()
block/nbd: introduce nbd_client_connection_new()
block/nbd: rename NBDConnectThread to NBDClientConnection
block/nbd: make nbd_co_establish_connection_cancel() bs-independent
...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

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async: the main AioContext is only "current" if under the BQL

If we want to wake up a coroutine from a worker thread, aio_co_wake()
currently does not work. In that scenario, aio_co_wake() calls
ai

async: the main AioContext is only "current" if under the BQL

If we want to wake up a coroutine from a worker thread, aio_co_wake()
currently does not work. In that scenario, aio_co_wake() calls
aio_co_enter(), but there is no current AioContext and therefore
qemu_get_current_aio_context() returns the main thread. aio_co_wake()
then attempts to call aio_context_acquire() instead of going through
aio_co_schedule().

The default case of qemu_get_current_aio_context() was added to cover
synchronous I/O started from the vCPU thread, but the main and vCPU
threads are quite different. The main thread is an I/O thread itself,
only running a more complicated event loop; the vCPU thread instead
is essentially a worker thread that occasionally calls
qemu_mutex_lock_iothread(). It is only in those critical sections
that it acts as if it were the home thread of the main AioContext.

Therefore, this patch detaches qemu_get_current_aio_context() from
iothreads, which is a useless complication. The AioContext pointer
is stored directly in the thread-local variable, including for the
main loop. Worker threads (including vCPU threads) optionally behave
as temporary home threads if they have taken the big QEMU lock,
but if that is not the case they will always schedule coroutines
on remote threads via aio_co_schedule().

With this change, the stub qemu_mutex_iothread_locked() must be changed
from true to false. The previous value of true was needed because the
main thread did not have an AioContext in the thread-local variable,
but now it does have one.

Reported-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210609122234.544153-1-pbonzini@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Tested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
[eblake: tweak commit message per Vladimir's review]
Signed-off-by: Eric Blake <eblake@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/thuth-gitlab/tags/pull-request-2021-03-12' into staging

* Move unit and bench tests into separate directories
* Clean-up and improve gitlab-ci jobs
* Drop the n

Merge remote-tracking branch 'remotes/thuth-gitlab/tags/pull-request-2021-03-12' into staging

* Move unit and bench tests into separate directories
* Clean-up and improve gitlab-ci jobs
* Drop the non-working "check-speed" makefile target
* Minor documentation updates

# gpg: Signature made Fri 12 Mar 2021 17:18:45 GMT
# gpg: using RSA key 27B88847EEE0250118F3EAB92ED9D774FE702DB5
# gpg: issuer "thuth@redhat.com"
# gpg: Good signature from "Thomas Huth <th.huth@gmx.de>" [full]
# gpg: aka "Thomas Huth <thuth@redhat.com>" [full]
# gpg: aka "Thomas Huth <huth@tuxfamily.org>" [full]
# gpg: aka "Thomas Huth <th.huth@posteo.de>" [unknown]
# Primary key fingerprint: 27B8 8847 EEE0 2501 18F3 EAB9 2ED9 D774 FE70 2DB5

* remotes/thuth-gitlab/tags/pull-request-2021-03-12:
README: Add Documentation blurb
MAINTAINERS: Merge the Gitlab-CI section into the generic CI section
tests: remove "make check-speed" in favor of "make bench"
gitlab-ci.yml: Merge check-crypto-old jobs into the build-crypto-old jobs
gitlab-ci.yml: Merge one of the coroutine jobs with the tcg-disabled job
gitlab-ci.yml: Add some missing dependencies to the jobs
gitlab-ci.yml: Move build-tools-and-docs-debian to a better place
tests: Move benchmarks into a separate folder
tests: Move unit tests into a separate directory

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

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tests: Move unit tests into a separate directory

The main tests directory still looks very crowded, and it's not
clear which files are part of a unit tests and which belong to
a different test subsy

tests: Move unit tests into a separate directory

The main tests directory still looks very crowded, and it's not
clear which files are part of a unit tests and which belong to
a different test subsystem. Let's clean up the mess and move the
unit tests to a separate directory.

Message-Id: <20210310063314.1049838-1-thuth@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

show more ...