Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- virtio-scsi: add iothread-vq-mapping parameter
- Improve writethrough performance
- Fix missing zero ini

Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- virtio-scsi: add iothread-vq-mapping parameter
- Improve writethrough performance
- Fix missing zero init in bdrv_snapshot_goto()
- Added scripts/qcow2-to-stdout.py
- Code cleanup and iotests fixes

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# gpg: using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg: issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6

* tag 'for-upstream' of https://repo.or.cz/qemu/kevin: (23 commits)
scripts/qcow2-to-stdout.py: Add script to write qcow2 images to stdout
virtio-scsi: only expose cmd vqs via iothread-vq-mapping
virtio-scsi: handle ctrl virtqueue in main loop
virtio-scsi: add iothread-vq-mapping parameter
virtio: extract iothread-vq-mapping.h API
virtio-blk: tidy up iothread_vq_mapping functions
virtio-blk: extract cleanup_iothread_vq_mapping() function
virtio-scsi: perform TMFs in appropriate AioContexts
virtio-scsi: protect events_dropped field
virtio-scsi: introduce event and ctrl virtqueue locks
scsi: introduce requests_lock
scsi: track per-SCSIRequest AioContext
dma: use current AioContext for dma_blk_io()
scsi-disk: drop unused SCSIDiskState->bh field
iotests: Limit qsd-migrate to working formats
aio-posix: Adjust polling time also for new handlers
aio-posix: Separate AioPolledEvent per AioHandler
aio-posix: Factor out adjust_polling_time()
aio: Create AioPolledEvent
block/io: Ignore FUA with cache.no-flush=on
...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

virtio-scsi: only expose cmd vqs via iothread-vq-mapping

Peter Krempa and Kevin Wolf observed that iothread-vq-mapping is
confusing to use because the control and event virtqueues have a fixed
locat

virtio-scsi: only expose cmd vqs via iothread-vq-mapping

Peter Krempa and Kevin Wolf observed that iothread-vq-mapping is
confusing to use because the control and event virtqueues have a fixed
location before the command virtqueues but need to be treated
differently.

Only expose the command virtqueues via iothread-vq-mapping so that the
command-line parameter is intuitive: it controls where SCSI requests are
processed.

The control virtqueue needs to be hardcoded to the main loop thread for
technical reasons anyway. Kevin also pointed out that it's better to
place the event virtqueue in the main loop thread since its no poll
behavior would prevent polling if assigned to an IOThread.

This change is its own commit to avoid squashing the previous commit.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Suggested-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20250311132616.1049687-14-stefanha@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

virtio-scsi: handle ctrl virtqueue in main loop

Previously the ctrl virtqueue was handled in the AioContext where SCSI
requests are processed. When IOThread Virtqueue Mapping was added things
become

virtio-scsi: handle ctrl virtqueue in main loop

Previously the ctrl virtqueue was handled in the AioContext where SCSI
requests are processed. When IOThread Virtqueue Mapping was added things
become more complicated because SCSI requests could run in other
AioContexts.

Simplify by handling the ctrl virtqueue in the main loop where reset
operations can be performed. Note that BHs are still used canceling SCSI
requests in their AioContexts but at least the mean loop activity
doesn't need BHs anymore.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20250311132616.1049687-13-stefanha@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

virtio-scsi: add iothread-vq-mapping parameter

Allow virtio-scsi virtqueues to be assigned to different IOThreads. This
makes it possible to take advantage of host multi-queue block layer
scalabilit

virtio-scsi: add iothread-vq-mapping parameter

Allow virtio-scsi virtqueues to be assigned to different IOThreads. This
makes it possible to take advantage of host multi-queue block layer
scalability by assigning virtqueues that have affinity with vCPUs to
different IOThreads that have affinity with host CPUs. The same feature
was introduced for virtio-blk in the past:
https://developers.redhat.com/articles/2024/09/05/scaling-virtio-blk-disk-io-iothread-virtqueue-mapping

Here are fio randread 4k iodepth=64 results from a 4 vCPU guest with an
Intel P4800X SSD:
iothreads IOPS
------------------------------
1 189576
2 312698
4 346744

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20250311132616.1049687-12-stefanha@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
[kwolf: Updated 051 output, virtio-scsi can now use any iothread]
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

Merge tag 'exec-20241220' of https://github.com/philmd/qemu into staging

Accel & Exec patch queue

- Ignore writes to CNTP_CTL_EL0 on HVF ARM (Alexander)
- Add '-d invalid_mem' logging option (Zolta

Merge tag 'exec-20241220' of https://github.com/philmd/qemu into staging

Accel & Exec patch queue

- Ignore writes to CNTP_CTL_EL0 on HVF ARM (Alexander)
- Add '-d invalid_mem' logging option (Zoltan)
- Create QOM containers explicitly (Peter)
- Rename sysemu/ -> system/ (Philippe)
- Re-orderning of include/exec/ headers (Philippe)
Move a lot of declarations from these legacy mixed bag headers:
. "exec/cpu-all.h"
. "exec/cpu-common.h"
. "exec/cpu-defs.h"
. "exec/exec-all.h"
. "exec/translate-all"
to these more specific ones:
. "exec/page-protection.h"
. "exec/translation-block.h"
. "user/cpu_loop.h"
. "user/guest-host.h"
. "user/page-protection.h"

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# gpg: Signature made Fri 20 Dec 2024 11:45:20 EST
# gpg: using RSA key FAABE75E12917221DCFD6BB2E3E32C2CDEADC0DE
# gpg: Good signature from "Philippe Mathieu-Daudé (F4BUG) <f4bug@amsat.org>" [unknown]
# 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: FAAB E75E 1291 7221 DCFD 6BB2 E3E3 2C2C DEAD C0DE

* tag 'exec-20241220' of https://github.com/philmd/qemu: (59 commits)
util/qemu-timer: fix indentation
meson: Do not define CONFIG_DEVICES on user emulation
system/accel-ops: Remove unnecessary 'exec/cpu-common.h' header
system/numa: Remove unnecessary 'exec/cpu-common.h' header
hw/xen: Remove unnecessary 'exec/cpu-common.h' header
target/mips: Drop left-over comment about Jazz machine
target/mips: Remove tswap() calls in semihosting uhi_fstat_cb()
target/xtensa: Remove tswap() calls in semihosting simcall() helper
accel/tcg: Un-inline translator_is_same_page()
accel/tcg: Include missing 'exec/translation-block.h' header
accel/tcg: Move tcg_cflags_has/set() to 'exec/translation-block.h'
accel/tcg: Restrict curr_cflags() declaration to 'internal-common.h'
qemu/coroutine: Include missing 'qemu/atomic.h' header
exec/translation-block: Include missing 'qemu/atomic.h' header
accel/tcg: Declare cpu_loop_exit_requested() in 'exec/cpu-common.h'
exec/cpu-all: Include 'cpu.h' earlier so MMU_USER_IDX is always defined
target/sparc: Move sparc_restore_state_to_opc() to cpu.c
target/sparc: Uninline cpu_get_tb_cpu_state()
target/loongarch: Declare loongarch_cpu_dump_state() locally
user: Move various declarations out of 'exec/exec-all.h'
...

Conflicts:
hw/char/riscv_htif.c
hw/intc/riscv_aplic.c
target/s390x/cpu.c

Apply sysemu header path changes to not in the pull request.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

include: Rename sysemu/ -> system/

Headers in include/sysemu/ are not only related to system
*emulation*, they are also used by virtualization. Rename
as system/ which is clearer.

Files renamed man

include: Rename sysemu/ -> system/

Headers in include/sysemu/ are not only related to system
*emulation*, they are also used by virtualization. Rename
as system/ which is clearer.

Files renamed manually then mechanical change using sed tool.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Lei Yang <leiyang@redhat.com>
Message-Id: <20241203172445.28576-1-philmd@linaro.org>

show more ...

Merge tag 'block-pull-request' of https://gitlab.com/stefanha/qemu into staging

Pull request

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Merge tag 'block-pull-request' of https://gitlab.com/stefanha/qemu into staging

Pull request

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# gpg: Signature made Mon 08 Jan 2024 16:37:25 GMT
# gpg: using RSA key 8695A8BFD3F97CDAAC35775A9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full]
# gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>" [full]
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35 775A 9CA4 ABB3 81AB 73C8

* tag 'block-pull-request' of https://gitlab.com/stefanha/qemu:
Rename "QEMU global mutex" to "BQL" in comments and docs
Replace "iothread lock" with "BQL" in comments
qemu/main-loop: rename qemu_cond_wait_iothread() to qemu_cond_wait_bql()
qemu/main-loop: rename QEMU_IOTHREAD_LOCK_GUARD to BQL_LOCK_GUARD
system/cpus: rename qemu_mutex_lock_iothread() to bql_lock()
iothread: Remove unused Error** argument in aio_context_set_aio_params

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

show more ...

Rename "QEMU global mutex" to "BQL" in comments and docs

The term "QEMU global mutex" is identical to the more widely used Big
QEMU Lock ("BQL"). Update the code comments and documentation to use
"B

Rename "QEMU global mutex" to "BQL" in comments and docs

The term "QEMU global mutex" is identical to the more widely used Big
QEMU Lock ("BQL"). Update the code comments and documentation to use
"BQL" instead of "QEMU global mutex".

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-id: 20240102153529.486531-6-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- virtio-blk: Multiqueue support (configurable iothread per queue)
- Made NBD export and hw/scsi thread-sa

Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- virtio-blk: Multiqueue support (configurable iothread per queue)
- Made NBD export and hw/scsi thread-safe without AioContext lock
- Fix crash when loading snapshot on inactive node

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# gpg: Signature made Thu 21 Dec 2023 18:02:23 EST
# gpg: using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg: issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6

* tag 'for-upstream' of https://repo.or.cz/qemu/kevin: (33 commits)
virtio-blk: add iothread-vq-mapping parameter
qdev: add IOThreadVirtQueueMappingList property type
qdev-properties: alias all object class properties
string-output-visitor: show structs as "<omitted>"
block-coroutine-wrapper: use qemu_get_current_aio_context()
block: remove outdated AioContext locking comments
job: remove outdated AioContext locking comments
scsi: remove outdated AioContext lock comment
docs: remove AioContext lock from IOThread docs
aio: remove aio_context_acquire()/aio_context_release() API
aio-wait: draw equivalence between AIO_WAIT_WHILE() and AIO_WAIT_WHILE_UNLOCKED()
scsi: remove AioContext locking
block: remove bdrv_co_lock()
block: remove AioContext locking
graph-lock: remove AioContext locking
aio: make aio_context_acquire()/aio_context_release() a no-op
tests: remove aio_context_acquire() tests
scsi: assert that callbacks run in the correct AioContext
virtio-scsi: replace AioContext lock with tmf_bh_lock
dma-helpers: don't lock AioContext in dma_blk_cb()
...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

virtio-scsi: don't lock AioContext around virtio_queue_aio_attach_host_notifier()

virtio_queue_aio_attach_host_notifier() does not require the AioContext
lock. Stop taking the lock and add an explic

virtio-scsi: don't lock AioContext around virtio_queue_aio_attach_host_notifier()

virtio_queue_aio_attach_host_notifier() does not require the AioContext
lock. Stop taking the lock and add an explicit smp_wmb() because we were
relying on the implicit barrier in the AioContext lock before.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231204164259.1515217-3-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

Merge tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu into staging

virtio,pc,pci: fixes, features, cleanups

asymmetric crypto support for cryptodev-vhost-user
rom migration w

Merge tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu into staging

virtio,pc,pci: fixes, features, cleanups

asymmetric crypto support for cryptodev-vhost-user
rom migration when rom size changes
poison get, inject, clear; mock cxl events and irq support for cxl
shadow virtqueue offload support for vhost-vdpa
vdpa now maps shadow vrings with MAP_SHARED
max_cpus went up to 1024 and we default to smbios 3.0 for pc

Fixes, cleanups all over the place. In particular
hw/acpi: Fix PM control register access
works around a very long standing bug in memory core.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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# gpg: Signature made Mon 26 Jun 2023 03:50:09 PM CEST
# gpg: using RSA key 5D09FD0871C8F85B94CA8A0D281F0DB8D28D5469
# gpg: issuer "mst@redhat.com"
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [undefined]
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>" [undefined]
# 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: 0270 606B 6F3C DF3D 0B17 0970 C350 3912 AFBE 8E67
# Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA 8A0D 281F 0DB8 D28D 5469

* tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu: (53 commits)
vhost-vdpa: do not cleanup the vdpa/vhost-net structures if peer nic is present
vhost_net: add an assertion for TAP client backends
intel_iommu: Fix address space unmap
intel_iommu: Fix flag check in replay
intel_iommu: Fix a potential issue in VFIO dirty page sync
vhost-user: fully use new backend/frontend naming
virtio-scsi: avoid dangling host notifier in ->ioeventfd_stop()
hw/i386/pc: Clean up pc_machine_initfn
vdpa: fix not using CVQ buffer in case of error
vdpa: mask _F_CTRL_GUEST_OFFLOADS for vhost vdpa devices
vhost: fix vhost_dev_enable_notifiers() error case
vdpa: Allow VIRTIO_NET_F_CTRL_GUEST_OFFLOADS in SVQ
vdpa: Add vhost_vdpa_net_load_offloads()
virtio-net: expose virtio_net_supported_guest_offloads()
hw/net/virtio-net: make some VirtIONet const
vdpa: reuse virtio_vdev_has_feature()
include/hw/virtio: make some VirtIODevice const
vdpa: map shadow vrings with MAP_SHARED
vdpa: reorder vhost_vdpa_net_cvq_cmd_page_len function
vdpa: do not block migration if device has cvq and x-svq=on
...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

hw/virtio: Remove unnecessary 'virtio-access.h' header

None of these files use the VirtIO Load/Store API declared
by "hw/virtio/virtio-access.h". This header probably crept
in via copy/pasting, remo

hw/virtio: Remove unnecessary 'virtio-access.h' header

None of these files use the VirtIO Load/Store API declared
by "hw/virtio/virtio-access.h". This header probably crept
in via copy/pasting, remove it.

Note, "virtio-access.h" is target-specific, so any file
including it also become tainted as target-specific.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230524093744.88442-10-philmd@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

show more ...

Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- Fix blockdev-create with iothreads
- Remove aio_disable_external() API

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Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- Fix blockdev-create with iothreads
- Remove aio_disable_external() API

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* tag 'for-upstream' of https://repo.or.cz/qemu/kevin: (32 commits)
aio: remove aio_disable_external() API
virtio: do not set is_external=true on host notifiers
virtio-scsi: implement BlockDevOps->drained_begin()
virtio-blk: implement BlockDevOps->drained_begin()
virtio: make it possible to detach host notifier from any thread
block/fuse: do not set is_external=true on FUSE fd
block/export: don't require AioContext lock around blk_exp_ref/unref()
block/export: rewrite vduse-blk drain code
hw/xen: do not set is_external=true on evtchn fds
xen-block: implement BlockDevOps->drained_begin()
block: drain from main loop thread in bdrv_co_yield_to_drain()
block: add blk_in_drain() API
hw/xen: do not use aio_set_fd_handler(is_external=true) in xen_xenstore
block/export: stop using is_external in vhost-user-blk server
block/export: wait for vhost-user-blk requests when draining
util/vhost-user-server: rename refcount to in_flight counter
virtio-scsi: stop using aio_disable_external() during unplug
virtio-scsi: avoid race between unplug and transport event
hw/qdev: introduce qdev_is_realized() helper
block-backend: split blk_do_set_aio_context()
...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

virtio-scsi: implement BlockDevOps->drained_begin()

The virtio-scsi Host Bus Adapter provides access to devices on a SCSI
bus. Those SCSI devices typically have a BlockBackend. When the
BlockBackend

virtio-scsi: implement BlockDevOps->drained_begin()

The virtio-scsi Host Bus Adapter provides access to devices on a SCSI
bus. Those SCSI devices typically have a BlockBackend. When the
BlockBackend enters a drained section, the SCSI device must temporarily
stop submitting new I/O requests.

Implement this behavior by temporarily stopping virtio-scsi virtqueue
processing when one of the SCSI devices enters a drained section. The
new scsi_device_drained_begin() API allows scsi-disk to message the
virtio-scsi HBA.

scsi_device_drained_begin() uses a drain counter so that multiple SCSI
devices can have overlapping drained sections. The HBA only sees one
pair of .drained_begin/end() calls.

After this commit, virtio-scsi no longer depends on hw/virtio's
ioeventfd aio_set_event_notifier(is_external=true). This commit is a
step towards removing the aio_disable_external() API.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230516190238.8401-19-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

virtio: make it possible to detach host notifier from any thread

virtio_queue_aio_detach_host_notifier() does two things:
1. It removes the fd handler from the event loop.
2. It processes the virtqu

virtio: make it possible to detach host notifier from any thread

virtio_queue_aio_detach_host_notifier() does two things:
1. It removes the fd handler from the event loop.
2. It processes the virtqueue one last time.

The first step can be peformed by any thread and without taking the
AioContext lock.

The second step may need the AioContext lock (depending on the device
implementation) and runs in the thread where request processing takes
place. virtio-blk and virtio-scsi therefore call
virtio_queue_aio_detach_host_notifier() from a BH that is scheduled in
AioContext.

The next patch will introduce a .drained_begin() function that needs to
call virtio_queue_aio_detach_host_notifier(). .drained_begin() functions
cannot call aio_poll() to wait synchronously for the BH. It is possible
for a .drained_poll() callback to asynchronously wait for the BH, but
that is more complex than necessary here.

Move the virtqueue processing out to the callers of
virtio_queue_aio_detach_host_notifier() so that the function can be
called from any thread. This is in preparation for the next patch.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230516190238.8401-17-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- Graph locking, part 3 (more block drivers)
- Compile out assert_bdrv_graph_readable() by default
- Add c

Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- Graph locking, part 3 (more block drivers)
- Compile out assert_bdrv_graph_readable() by default
- Add configure options for vmdk, vhdx and vpc
- Fix use after free in blockdev_mark_auto_del()
- migration: Attempt disk reactivation in more failure scenarios
- Coroutine correctness fixes

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# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]

* tag 'for-upstream' of https://repo.or.cz/qemu/kevin: (28 commits)
block: compile out assert_bdrv_graph_readable() by default
block: Mark bdrv_refresh_limits() and callers GRAPH_RDLOCK
block: Mark bdrv_recurse_can_replace() and callers GRAPH_RDLOCK
block: Mark bdrv_query_block_graph_info() and callers GRAPH_RDLOCK
block: Mark bdrv_query_bds_stats() and callers GRAPH_RDLOCK
block: Mark BlockDriver callbacks for amend job GRAPH_RDLOCK
block: Mark bdrv_co_debug_event() GRAPH_RDLOCK
block: Mark bdrv_co_get_info() and callers GRAPH_RDLOCK
block: Mark bdrv_co_get_allocated_file_size() and callers GRAPH_RDLOCK
mirror: Require GRAPH_RDLOCK for accessing a node's parent list
vhdx: Require GRAPH_RDLOCK for accessing a node's parent list
nbd: Mark nbd_co_do_establish_connection() and callers GRAPH_RDLOCK
nbd: Remove nbd_co_flush() wrapper function
block: .bdrv_open is non-coroutine and unlocked
graph-lock: Fix GRAPH_RDLOCK_GUARD*() to be reader lock
graph-lock: Add GRAPH_UNLOCKED(_PTR)
test-bdrv-drain: Don't modify the graph in coroutines
iotests: Test resizing image attached to an iothread
block: Don't call no_coroutine_fns in qmp_block_resize()
block: bdrv/blk_co_unref() for calls in coroutine context
...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

aio-wait: avoid AioContext lock in aio_wait_bh_oneshot()

There is no need for the AioContext lock in aio_wait_bh_oneshot().
It's easy to remove the lock from existing callers and then switch from
AI

aio-wait: avoid AioContext lock in aio_wait_bh_oneshot()

There is no need for the AioContext lock in aio_wait_bh_oneshot().
It's easy to remove the lock from existing callers and then switch from
AIO_WAIT_WHILE() to AIO_WAIT_WHILE_UNLOCKED() in aio_wait_bh_oneshot().

Document that the AioContext lock should not be held across
aio_wait_bh_oneshot(). Holding a lock across aio_poll() can cause
deadlock so we don't want callers to do that.

This is a step towards getting rid of the AioContext lock.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230404153307.458883-1-stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

Merge tag 'for_upstream' of git://git.kernel.org/pub/scm/virt/kvm/mst/qemu into staging

pc,virtio: fixes

Several bugfixes, they all look very safe to me. Revert
seed support since we aren't any clo

Merge tag 'for_upstream' of git://git.kernel.org/pub/scm/virt/kvm/mst/qemu into staging

pc,virtio: fixes

Several bugfixes, they all look very safe to me. Revert
seed support since we aren't any closer to a proper fix.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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* tag 'for_upstream' of git://git.kernel.org/pub/scm/virt/kvm/mst/qemu:
virtio-pci: don't touch pci on virtio reset
tests: acpi: silence applesmc warning about invalid key
hw/cxl: Correctly handle variable sized mailbox input payloads.
hw/cxl: Fix Get LSA input payload size which should be 8 bytes.
hw/cxl: Add stub write function for RO MemoryRegionOps entries.
hw/cxl: Fix wrong query of target ports
hw/cxl: Fix memory leak in error paths
x86: disable rng seeding via setup_data
hw/virtio: fix vhost_user_read tracepoint
hw/virtio: handle un-configured shutdown in virtio-pci
hw/virtio: gracefully handle unset vhost_dev vdev
virtio-scsi: fix race in virtio_scsi_dataplane_start()

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

virtio-scsi: fix race in virtio_scsi_dataplane_start()

As soon as virtio_scsi_data_plane_start() attaches host notifiers the
IOThread may start virtqueue processing. There is a race between
IOThread

virtio-scsi: fix race in virtio_scsi_dataplane_start()

As soon as virtio_scsi_data_plane_start() attaches host notifiers the
IOThread may start virtqueue processing. There is a race between
IOThread virtqueue processing and virtio_scsi_data_plane_start() because
it only assigns s->dataplane_started after attaching host notifiers.

When a virtqueue handler function in the IOThread calls
virtio_scsi_defer_to_dataplane() it may see !s->dataplane_started and
attempt to start dataplane even though we're already in the IOThread:

#0 0x00007f67b360857c __pthread_kill_implementation (libc.so.6 + 0xa257c)
#1 0x00007f67b35bbd56 raise (libc.so.6 + 0x55d56)
#2 0x00007f67b358e833 abort (libc.so.6 + 0x28833)
#3 0x00007f67b358e75b __assert_fail_base.cold (libc.so.6 + 0x2875b)
#4 0x00007f67b35b4cd6 __assert_fail (libc.so.6 + 0x4ecd6)
#5 0x000055ca87fd411b memory_region_transaction_commit (qemu-kvm + 0x67511b)
#6 0x000055ca87e17811 virtio_pci_ioeventfd_assign (qemu-kvm + 0x4b8811)
#7 0x000055ca87e14836 virtio_bus_set_host_notifier (qemu-kvm + 0x4b5836)
#8 0x000055ca87f8e14e virtio_scsi_set_host_notifier (qemu-kvm + 0x62f14e)
#9 0x000055ca87f8dd62 virtio_scsi_dataplane_start (qemu-kvm + 0x62ed62)
#10 0x000055ca87e14610 virtio_bus_start_ioeventfd (qemu-kvm + 0x4b5610)
#11 0x000055ca87f8c29a virtio_scsi_handle_ctrl (qemu-kvm + 0x62d29a)
#12 0x000055ca87fa5902 virtio_queue_host_notifier_read (qemu-kvm + 0x646902)
#13 0x000055ca882c099e aio_dispatch_handler (qemu-kvm + 0x96199e)
#14 0x000055ca882c1761 aio_poll (qemu-kvm + 0x962761)
#15 0x000055ca880e1052 iothread_run (qemu-kvm + 0x782052)
#16 0x000055ca882c562a qemu_thread_start (qemu-kvm + 0x96662a)

This patch assigns s->dataplane_started before attaching host notifiers
so that virtqueue handler functions that run in the IOThread before
virtio_scsi_data_plane_start() returns correctly identify that dataplane
does not need to be started. This fix is taken from the virtio-blk
dataplane code and it's worth adding a comment in virtio-blk as well to
explain why it works.

Note that s->dataplane_started does not need the AioContext lock because
it is set before attaching host notifiers and cleared after detaching
host notifiers. In other words, the IOThread always sees the value true
and the main loop thread does not modify it while the IOThread is
active.

Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2099541
Reported-by: Qing Wang <qinwang@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20220808162134.240405-1-stefanha@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

show more ...

Merge tag 'block-pull-request' of https://gitlab.com/stefanha/qemu into staging

Pull request

- Add new thread-pool-min/thread-pool-max parameters to control the thread pool
used for async I/O.

-

Merge tag 'block-pull-request' of https://gitlab.com/stefanha/qemu into staging

Pull request

- Add new thread-pool-min/thread-pool-max parameters to control the thread pool
used for async I/O.

- Fix virtio-scsi IOThread 100% CPU consumption QEMU 7.0 regression.

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# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full]
# gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>" [full]

* tag 'block-pull-request' of https://gitlab.com/stefanha/qemu:
virtio-scsi: move request-related items from .h to .c
virtio-scsi: clean up virtio_scsi_handle_cmd_vq()
virtio-scsi: clean up virtio_scsi_handle_ctrl_vq()
virtio-scsi: clean up virtio_scsi_handle_event_vq()
virtio-scsi: don't waste CPU polling the event virtqueue
virtio-scsi: fix ctrl and event handler functions in dataplane mode
util/event-loop-base: Introduce options to set the thread pool size
util/main-loop: Introduce the main loop into QOM
Introduce event-loop-base abstract class

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

virtio-scsi: don't waste CPU polling the event virtqueue

The virtio-scsi event virtqueue is not emptied by its handler function.
This is typical for rx virtqueues where the device uses buffers when

virtio-scsi: don't waste CPU polling the event virtqueue

The virtio-scsi event virtqueue is not emptied by its handler function.
This is typical for rx virtqueues where the device uses buffers when
some event occurs (e.g. a packet is received, an error condition
happens, etc).

Polling non-empty virtqueues wastes CPU cycles. We are not waiting for
new buffers to become available, we are waiting for an event to occur,
so it's a misuse of CPU resources to poll for buffers.

Introduce the new virtio_queue_aio_attach_host_notifier_no_poll() API,
which is identical to virtio_queue_aio_attach_host_notifier() except
that it does not poll the virtqueue.

Before this patch the following command-line consumed 100% CPU in the
IOThread polling and calling virtio_scsi_handle_event():

$ qemu-system-x86_64 -M accel=kvm -m 1G -cpu host \
--object iothread,id=iothread0 \
--device virtio-scsi-pci,iothread=iothread0 \
--blockdev file,filename=test.img,aio=native,cache.direct=on,node-name=drive0 \
--device scsi-hd,drive=drive0

After this patch CPU is no longer wasted.

Reported-by: Nir Soffer <nsoffer@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Nir Soffer <nsoffer@redhat.com>
Message-id: 20220427143541.119567-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/stefanha-gitlab/tags/block-pull-request' into staging

Pull request

# gpg: Signature made Wed 12 Jan 2022 17:13:54 GMT
# gpg: using RSA key 8695A

Merge remote-tracking branch 'remotes/stefanha-gitlab/tags/block-pull-request' into staging

Pull request

# gpg: Signature made Wed 12 Jan 2022 17:13:54 GMT
# gpg: using RSA key 8695A8BFD3F97CDAAC35775A9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full]
# gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>" [full]
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35 775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha-gitlab/tags/block-pull-request:
virtio: unify dataplane and non-dataplane ->handle_output()
virtio: use ->handle_output() instead of ->handle_aio_output()
virtio-scsi: prepare virtio_scsi_handle_cmd for dataplane
virtio-blk: drop unused virtio_blk_handle_vq() return value
virtio: get rid of VirtIOHandleAIOOutput
aio-posix: split poll check from ready handler

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

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virtio: unify dataplane and non-dataplane ->handle_output()

Now that virtio-blk and virtio-scsi are ready, get rid of
the handle_aio_output() callback. It's no longer needed.

Signed-off-by: Stefan

virtio: unify dataplane and non-dataplane ->handle_output()

Now that virtio-blk and virtio-scsi are ready, get rid of
the handle_aio_output() callback. It's no longer needed.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20211207132336.36627-7-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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virtio: get rid of VirtIOHandleAIOOutput

The virtqueue host notifier API
virtio_queue_aio_set_host_notifier_handler() polls the virtqueue for new
buffers. AioContext previously required a bool progr

virtio: get rid of VirtIOHandleAIOOutput

The virtqueue host notifier API
virtio_queue_aio_set_host_notifier_handler() polls the virtqueue for new
buffers. AioContext previously required a bool progress return value
indicating whether an event was handled or not. This is no longer
necessary because the AioContext polling API has been split into a poll
check function and an event handler function. The event handler is only
run when we know there is work to do, so it doesn't return bool.

The VirtIOHandleAIOOutput function signature is now the same as
VirtIOHandleOutput. Get rid of the bool return value.

Further simplifications will be made for virtio-blk and virtio-scsi in
the next patch.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20211207132336.36627-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

pc,pci,virtio: bugfixes, improvements

vhost-user-rng support.
Fixes all over the place.

Signed-off-by: Michael S. Tsirkin

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

pc,pci,virtio: bugfixes, improvements

vhost-user-rng support.
Fixes all over the place.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Wed 07 Jul 2021 14:29:30 BST
# gpg: using RSA key 5D09FD0871C8F85B94CA8A0D281F0DB8D28D5469
# gpg: issuer "mst@redhat.com"
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17 0970 C350 3912 AFBE 8E67
# Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA 8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream:
MAINTAINERS: Add maintainer for vhost-user RNG implementation
docs: add slot when adding new PCIe root port
acpi/ged: fix reset cause
tests: acpi: pc: update expected DSDT blobs
acpi: pc: revert back to v5.2 PCI slot enumeration
tests: acpi: prepare for changing DSDT tables
migration: failover: reset partially_hotplugged
virtio-pci: Changed return values for "notify", "device" and "isr" read.
virtio-pci: Added check for virtio device in PCI config cbs.
virtio-pci: Added check for virtio device presence in mm callbacks.
hw/pci-host/q35: Ignore write of reserved PCIEXBAR LENGTH field
virtio: Clarify MR transaction optimization
virtio: disable ioeventfd for record/replay

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

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