Commit Graph

958 Commits

Author SHA1 Message Date
Linus Torvalds
77fa2fbe87 vhost,virtio,vdpa: features, fixes, cleanups
vdpa/mlx5:
 	VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK
 	new maintainer
 vdpa:
 	support for vq descriptor mappings
 	decouple reset of iotlb mapping from device reset
 
 fixes, cleanups all over the place
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:
 "vhost,virtio,vdpa: features, fixes, cleanups.

  vdpa/mlx5:
   - VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK
   - new maintainer

  vdpa:
   - support for vq descriptor mappings
   - decouple reset of iotlb mapping from device reset

  and fixes, cleanups all over the place"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (34 commits)
  vdpa_sim: implement .reset_map support
  vdpa/mlx5: implement .reset_map driver op
  vhost-vdpa: clean iotlb map during reset for older userspace
  vdpa: introduce .compat_reset operation callback
  vhost-vdpa: introduce IOTLB_PERSIST backend feature bit
  vhost-vdpa: reset vendor specific mapping to initial state in .release
  vdpa: introduce .reset_map operation callback
  virtio_pci: add check for common cfg size
  virtio-blk: fix implicit overflow on virtio_max_dma_size
  virtio_pci: add build offset check for the new common cfg items
  virtio: add definition of VIRTIO_F_NOTIF_CONFIG_DATA feature bit
  vduse: make vduse_class constant
  vhost-scsi: Spelling s/preceeding/preceding/g
  virtio: kdoc for struct virtio_pci_modern_device
  vdpa: Update sysfs ABI documentation
  MAINTAINERS: Add myself as mlx5_vdpa driver
  virtio-balloon: correct the comment of virtballoon_migratepage()
  mlx5_vdpa: offer VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK
  vdpa/mlx5: Update cvq iotlb mapping on ASID change
  vdpa/mlx5: Make iotlb helper functions more generic
  ...
2023-11-05 09:02:32 -10:00
Linus Torvalds
6ed92e559a SCSI misc on 20231102
Updates to the usual drivers (ufs, megaraid_sas, lpfc, target, ibmvfc,
 scsi_debug) plus the usual assorted minor fixes and updates.  The
 major change this time around is a prep patch for rethreading of the
 driver reset handler API not to take a scsi_cmd structure which starts
 to reduce various drivers' dependence on scsi_cmd in error handling.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "Updates to the usual drivers (ufs, megaraid_sas, lpfc, target, ibmvfc,
  scsi_debug) plus the usual assorted minor fixes and updates.

  The major change this time around is a prep patch for rethreading of
  the driver reset handler API not to take a scsi_cmd structure which
  starts to reduce various drivers' dependence on scsi_cmd in error
  handling"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (132 commits)
  scsi: ufs: core: Leave space for '\0' in utf8 desc string
  scsi: ufs: core: Conversion to bool not necessary
  scsi: ufs: core: Fix race between force complete and ISR
  scsi: megaraid: Fix up debug message in megaraid_abort_and_reset()
  scsi: aic79xx: Fix up NULL command in ahd_done()
  scsi: message: fusion: Initialize return value in mptfc_bus_reset()
  scsi: mpt3sas: Fix loop logic
  scsi: snic: Remove useless code in snic_dr_clean_pending_req()
  scsi: core: Add comment to target_destroy in scsi_host_template
  scsi: core: Clean up scsi_dev_queue_ready()
  scsi: pmcraid: Add missing scsi_device_put() in pmcraid_eh_target_reset_handler()
  scsi: target: core: Fix kernel-doc comment
  scsi: pmcraid: Fix kernel-doc comment
  scsi: core: Handle depopulation and restoration in progress
  scsi: ufs: core: Add support for parsing OPP
  scsi: ufs: core: Add OPP support for scaling clocks and regulators
  scsi: ufs: dt-bindings: common: Add OPP table
  scsi: scsi_debug: Add param to control sdev's allow_restart
  scsi: scsi_debug: Add debugfs interface to fail target reset
  scsi: scsi_debug: Add new error injection type: Reset LUN failed
  ...
2023-11-02 15:13:50 -10:00
Si-Wei Liu
bc91df5c70 vhost-vdpa: clean iotlb map during reset for older userspace
Using .compat_reset op from the previous patch, the buggy .reset
behaviour can be kept as-is on older userspace apps, which don't ack the
IOTLB_PERSIST backend feature. As this compatibility quirk is limited to
those drivers that used to be buggy in the past, it won't affect change
the behaviour or affect ABI on the setups with API compliant driver.

The separation of .compat_reset from the regular .reset allows
vhost-vdpa able to know which driver had broken behaviour before, so it
can apply the corresponding compatibility quirk to the individual driver
whenever needed.  Compared to overloading the existing .reset with
flags, .compat_reset won't cause any extra burden to the implementation
of every compliant driver.

[mst: squashed in two fixup commits]

Message-Id: <1697880319-4937-6-git-send-email-si-wei.liu@oracle.com>
Message-Id: <1698102863-21122-1-git-send-email-si-wei.liu@oracle.com>
Reported-by: Dragos Tatulea <dtatulea@nvidia.com>
Tested-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <1698275594-19204-1-git-send-email-si-wei.liu@oracle.com>
Reported-by: Lei Yang <leiyang@redhat.com>
Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
2023-11-01 09:20:00 -04:00
Si-Wei Liu
4398776f7a vhost-vdpa: introduce IOTLB_PERSIST backend feature bit
Userspace needs this feature flag to distinguish if vhost-vdpa iotlb in
the kernel can be trusted to persist IOTLB mapping across vDPA reset.
Without it, userspace has no way to tell apart if it's running on an
older kernel, which could silently drop all iotlb mapping across vDPA
reset, especially with broken parent driver implementation for the
.reset driver op. The broken driver may incorrectly drop all mappings of
its own as part of .reset, which inadvertently ends up with corrupted
mapping state between vhost-vdpa userspace and the kernel. As a
workaround, to make the mapping behaviour predictable across reset,
userspace has to pro-actively remove all mappings before vDPA reset, and
then restore all the mappings afterwards. This workaround is done
unconditionally on top of all parent drivers today, due to the parent
driver implementation issue and no means to differentiate.  This
workaround had been utilized in QEMU since day one when the
corresponding vhost-vdpa userspace backend came to the world.

There are 3 cases that backend may claim this feature bit on for:

- parent device that has to work with platform IOMMU
- parent device with on-chip IOMMU that has the expected
  .reset_map support in driver
- parent device with vendor specific IOMMU implementation with
  persistent IOTLB mapping already that has to specifically
  declare this backend feature

The reason why .reset_map is being one of the pre-condition for
persistent iotlb is because without it, vhost-vdpa can't switch back
iotlb to the initial state later on, especially for the on-chip IOMMU
case which starts with identity mapping at device creation. virtio-vdpa
requires on-chip IOMMU to perform 1:1 passthrough translation from PA to
IOVA as-is to begin with, and .reset_map is the only means to turn back
iotlb to the identity mapping mode after vhost-vdpa is gone.

The difference in behavior did not matter as QEMU unmaps all the memory
unregistering the memory listener at vhost_vdpa_dev_start( started =
false), but the backend acknowledging this feature flag allows QEMU to
make sure it is safe to skip this unmap & map in the case of vhost stop
& start cycle.

In that sense, this feature flag is actually a signal for userspace to
know that the driver bug has been solved. Not offering it indicates that
userspace cannot trust the kernel will retain the maps.

Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <1697880319-4937-4-git-send-email-si-wei.liu@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
2023-11-01 09:20:00 -04:00
Si-Wei Liu
1d0f874bfe vhost-vdpa: reset vendor specific mapping to initial state in .release
Devices with on-chip IOMMU or vendor specific IOTLB implementation may
need to restore iotlb mapping to the initial or default state using the
.reset_map op, as it's desirable for some parent devices to not work
with DMA ops and maintain a simple IOMMU model with .reset_map. In
particular, device reset should not cause mapping to go away on such
IOTLB model, so persistent mapping is implied across reset. Before the
userspace process using vhost-vdpa is gone, give it a chance to reset
iotlb back to the initial state in vhost_vdpa_cleanup().

Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <1697880319-4937-3-git-send-email-si-wei.liu@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
2023-11-01 09:19:59 -04:00
Geert Uytterhoeven
5ff1f51eef vhost-scsi: Spelling s/preceeding/preceding/g
Fix a misspelling of "preceding".

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Message-Id: <b57b882675809f1f9dacbf42cf6b920b2bea9cba.1695903476.git.geert+renesas@glider.be>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-11-01 09:19:59 -04:00
Si-Wei Liu
c8068d9bae vhost-vdpa: uAPI to get dedicated descriptor group id
With _F_DESC_ASID backend feature, the device can now support the
VHOST_VDPA_GET_VRING_DESC_GROUP ioctl, and it may expose the descriptor
table (including avail and used ring) in a different group than the
buffers it contains. This new uAPI will fetch the group ID of the
descriptor table.

Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231018171456.1624030-6-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Lei Yang <leiyang@redhat.com>
2023-11-01 09:19:55 -04:00
Si-Wei Liu
7db0d6027e vhost-vdpa: introduce descriptor group backend feature
Userspace knows if the device has dedicated descriptor group or not
by checking this feature bit.

It's only exposed if the vdpa driver backend implements the
.get_vq_desc_group() operation callback. Userspace trying to negotiate
this feature when it or the dependent _F_IOTLB_ASID feature hasn't
been exposed will result in an error.

Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231018171456.1624030-5-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Lei Yang <leiyang@redhat.com>
2023-11-01 09:19:55 -04:00
Jakub Kicinski
ec4c20ca09 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

net/mac80211/rx.c
  91535613b6 ("wifi: mac80211: don't drop all unprotected public action frames")
  6c02fab724 ("wifi: mac80211: split ieee80211_drop_unencrypted_mgmt() return value")

Adjacent changes:

drivers/net/ethernet/apm/xgene/xgene_enet_main.c
  61471264c0 ("net: ethernet: apm: Convert to platform remove callback returning void")
  d2ca43f306 ("net: xgene: Fix unused xgene_enet_of_match warning for !CONFIG_OF")

net/vmw_vsock/virtio_transport.c
  64c99d2d6a ("vsock/virtio: support to send non-linear skb")
  53b08c4985 ("vsock/virtio: initialize the_virtio_vsock before using VQs")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-26 13:46:28 -07:00
Eric Auger
ca50ec377c vhost: Allow null msg.size on VHOST_IOTLB_INVALIDATE
Commit e2ae38cf3d ("vhost: fix hung thread due to erroneous iotlb
entries") Forbade vhost iotlb msg with null size to prevent entries
with size = start = 0 and last = ULONG_MAX to end up in the iotlb.

Then commit 95932ab2ea ("vhost: allow batching hint without size")
only applied the check for VHOST_IOTLB_UPDATE and VHOST_IOTLB_INVALIDATE
message types to fix a regression observed with batching hit.

Still, the introduction of that check introduced a regression for
some users attempting to invalidate the whole ULONG_MAX range by
setting the size to 0. This is the case with qemu/smmuv3/vhost
integration which does not work anymore. It Looks safe to partially
revert the original commit and allow VHOST_IOTLB_INVALIDATE messages
with null size. vhost_iotlb_del_range() will compute a correct end
iova. Same for vhost_vdpa_iotlb_unmap().

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Fixes: e2ae38cf3d ("vhost: fix hung thread due to erroneous iotlb entries")
Cc: stable@vger.kernel.org # v5.17+
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230927140544.205088-1-eric.auger@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-10-18 11:29:56 -04:00
Arseniy Krasnov
3719c48d9a vhost/vsock: support MSG_ZEROCOPY for transport
Add 'msgzerocopy_allow()' callback for vhost transport.

Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-10-15 13:19:42 +01:00
Mike Christie
e2f4ea4013 scsi: target: Allow userspace to request direct submissions
This allows userspace to request the fabric drivers do direct submissions
if they support it. With the new device file, submit_type, users can
write 0 - 2 to control how commands are submitted to the backend:

 0 - TARGET_FABRIC_DEFAULT_SUBMIT - LIO will use the fabric's default
     submission type. This is the default for compat.

 1 - TARGET_DIRECT_SUBMIT - LIO will submit the cmd to the backend from the
     calling context if the fabric the cmd was received on supports it,
     else it will use the fabric's default type.

 2 - TARGET_QUEUE_SUBMIT - LIO will queue the cmd to the LIO submission
     workqueue which will pass it to the backend.

When using an NVMe drive and vhost-scsi with direct submission we see
around a 20% improvement in 4K I/Os:

fio jobs        1       2       4       8       10
--------------------------------------------------
defer           94K     190K    394K    770K    890K
direct          128K    252K    488K    950K    -

And when using the queueing mode, we now no longer see issues like where
the iSCSI tx thread is blocked in the block layer waiting on a tag so it
can't respond to a nop or perform I/Os for other LUs.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20230928020907.5730-6-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2023-10-13 15:53:58 -04:00
Mike Christie
194605d45d scsi: target: Have drivers report if they support direct submissions
In some cases, like with multiple LUN targets or where the target has to
respond to transport level requests from the receiving context it can be
better to defer cmd submission to a helper thread. If the backend driver
blocks on something like request/tag allocation it can block the entire
target submission path and other LUs and transport IO on that session.

In other cases like single LUN targets with storage that can support all
the commands that the target can queue, then it's best to submit the cmd
to the backend from the target's cmd receiving context.

Subsequent commits will allow the user to config what they prefer, but
drivers like loop can't directly submit because they can be called from a
context that can't sleep. And, drivers like vhost-scsi can support direct
submission, but need to keep their default behavior of deferring execution
to avoid possible regressions where the backend can block.

Make the drivers tell LIO core if they support direct submissions and their
current default, so we can prevent users from misconfiguring the system and
initialize devices correctly.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20230928020907.5730-2-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2023-10-13 15:53:57 -04:00
Jakub Kicinski
2606cf059c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

No conflicts (or adjacent changes of note).

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-05 13:16:47 -07:00
Stefano Garzarella
7aed44babc vringh: don't use vringh_kiov_advance() in vringh_iov_xfer()
In the while loop of vringh_iov_xfer(), `partlen` could be 0 if one of
the `iov` has 0 lenght.
In this case, we should skip the iov and go to the next one.
But calling vringh_kiov_advance() with 0 lenght does not cause the
advancement, since it returns immediately if asked to advance by 0 bytes.

Let's restore the code that was there before commit b8c06ad4d6
("vringh: implement vringh_kiov_advance()"), avoiding using
vringh_kiov_advance().

Fixes: b8c06ad4d6 ("vringh: implement vringh_kiov_advance()")
Cc: stable@vger.kernel.org
Reported-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-10-04 08:26:48 +01:00
Arseniy Krasnov
0df7cd3c13 vsock/virtio/vhost: read data from non-linear skb
This is preparation patch for MSG_ZEROCOPY support. It adds handling of
non-linear skbs by replacing direct calls of 'memcpy_to_msg()' with
'skb_copy_datagram_iter()'. Main advantage of the second one is that it
can handle paged part of the skb by using 'kmap()' on each page, but if
there are no pages in the skb, it behaves like simple copying to iov
iterator. This patch also adds new field to the control block of skb -
this value shows current offset in the skb to read next portion of data
(it doesn't matter linear it or not). Idea behind this field is that
'skb_copy_datagram_iter()' handles both types of skb internally - it
just needs an offset from which to copy data from the given skb. This
offset is incremented on each read from skb. This approach allows to
simplify handling of both linear and non-linear skbs, because for
linear skb we need to call 'skb_pull()' after reading data from it,
while in non-linear case we need to update 'data_len'.

Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-21 12:34:00 +02:00
Eugenio Pérez
b63e5c70c3 vdpa: add get_backend_features vdpa operation
This operation allow vdpa parent to expose its own backend feature bits.

Next patches introduce a feature not compatible with all parent drivers:
the ability to enable vq after driver_ok.  Each parent must declare if
it allows it or not.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Shannon Nelson <shannon.nelson@amd.com>
Message-Id: <20230609092127.170673-4-eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-09-03 18:10:22 -04:00
Eugenio Pérez
9f09fd6171 vdpa: accept VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK backend feature
Accepting VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK backend feature if
userland sets it.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Shannon Nelson <shannon.nelson@amd.com>
Message-Id: <20230609092127.170673-3-eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-09-03 18:10:22 -04:00
Mike Christie
c5ace19efb vhost-scsi: Rename vhost_scsi_iov_to_sgl
Rename vhost_scsi_iov_to_sgl to vhost_scsi_map_iov_to_sgl so it matches
matches the naming style used for vhost_scsi_copy_iov_to_sgl.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230709202859.138387-3-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-08-10 15:24:28 -04:00
Mike Christie
5ced58bfa1 vhost-scsi: Fix alignment handling with windows
The linux block layer requires bios/requests to have lengths with a 512
byte alignment. Some drivers/layers like dm-crypt and the directi IO code
will test for it and just fail. Other drivers like SCSI just assume the
requirement is met and will end up in infinte retry loops. The problem
for drivers like SCSI is that it uses functions like blk_rq_cur_sectors
and blk_rq_sectors which divide the request's length by 512. If there's
lefovers then it just gets dropped. But other code in the block/scsi
layer may use blk_rq_bytes/blk_rq_cur_bytes and end up thinking there is
still data left and try to retry the cmd. We can then end up getting
stuck in retry loops where part of the block/scsi thinks there is data
left, but other parts think we want to do IOs of zero length.

Linux will always check for alignment, but windows will not. When
vhost-scsi then translates the iovec it gets from a windows guest to a
scatterlist, we can end up with sg items where the sg->length is not
divisible by 512 due to the misaligned offset:

sg[0].offset = 255;
sg[0].length = 3841;
sg...
sg[N].offset = 0;
sg[N].length = 255;

When the lio backends then convert the SG to bios or other iovecs, we
end up sending them with the same misaligned values and can hit the
issues above.

This just has us drop down to allocating a temp page and copying the data
when we detect a misaligned buffer and the IO is large enough that it
will get split into multiple bad IOs.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230709202859.138387-2-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-08-10 15:24:27 -04:00
Linus Torvalds
a8d70602b1 virtio: features, fixes, cleanups
resume support in vdpa/solidrun
 structure size optimizations in virtio_pci
 new pds_vdpa driver
 immediate initialization mechanism for vdpa/ifcvf
 interrupt bypass for vdpa/mlx5
 multiple worker support for vhost
 viirtio net in Intel F2000X-PL support for vdpa/ifcvf
 
 fixes, cleanups all over the place
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:

 - resume support in vdpa/solidrun

 - structure size optimizations in virtio_pci

 - new pds_vdpa driver

 - immediate initialization mechanism for vdpa/ifcvf

 - interrupt bypass for vdpa/mlx5

 - multiple worker support for vhost

 - viirtio net in Intel F2000X-PL support for vdpa/ifcvf

 - fixes, cleanups all over the place

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (48 commits)
  vhost: Make parameter name match of vhost_get_vq_desc()
  vduse: fix NULL pointer dereference
  vhost: Allow worker switching while work is queueing
  vhost_scsi: add support for worker ioctls
  vhost: allow userspace to create workers
  vhost: replace single worker pointer with xarray
  vhost: add helper to parse userspace vring state/file
  vhost: remove vhost_work_queue
  vhost_scsi: flush IO vqs then send TMF rsp
  vhost_scsi: convert to vhost_vq_work_queue
  vhost_scsi: make SCSI cmd completion per vq
  vhost_sock: convert to vhost_vq_work_queue
  vhost: convert poll work to be vq based
  vhost: take worker or vq for flushing
  vhost: take worker or vq instead of dev for queueing
  vhost, vhost_net: add helper to check if vq has work
  vhost: add vhost_worker pointer to vhost_virtqueue
  vhost: dynamically allocate vhost_worker
  vhost: create worker at end of vhost_dev_set_owner
  virtio_bt: call scheduler when we free unused buffs
  ...
2023-07-03 15:38:26 -07:00
Xianting Tian
9e396a2f43 vhost: Make parameter name match of vhost_get_vq_desc()
The parameter name in the function declaration and definition
should be the same.

drivers/vhost/vhost.h,
int vhost_get_vq_desc(..., unsigned int iov_count,...);

drivers/vhost/vhost.c,
int vhost_get_vq_desc(..., unsigned int iov_size,...)

Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>
Message-Id: <20230621093835.36878-1-xianting.tian@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:15 -04:00
Mike Christie
228a27cf78 vhost: Allow worker switching while work is queueing
This patch drops the requirement that we can only switch workers if work
has not been queued by using RCU for the vq based queueing paths and a
mutex for the device wide flush.

We can also use this to support SIGKILL properly in the future where we
should exit almost immediately after getting that signal. With this
patch, when get_signal returns true, we can set the vq->worker to NULL
and do a synchronize_rcu to prevent new work from being queued to the
vhost_task that has been killed.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-18-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:14 -04:00
Mike Christie
d74b55e655 vhost_scsi: add support for worker ioctls
This has vhost-scsi support the worker ioctls by calling the
vhost_worker_ioctl helper.

With a single worker, the single thread becomes a bottlneck when trying
to use 3 or more virtqueues like:

fio --filename=/dev/sdb  --direct=1 --rw=randrw --bs=4k \
--ioengine=libaio --iodepth=128  --numjobs=3

With the patches and doing a worker per vq, we can scale to at least
16 vCPUs/vqs (that's my system limit) with the same command fio command
above with numjobs=16:

fio --filename=/dev/sdb  --direct=1 --rw=randrw --bs=4k \
--ioengine=libaio --iodepth=64  --numjobs=16

which gives around 2002K IOPs.

Note that for testing I dropped depth to 64 above because the vhost/virt
layer supports only 1024 total commands per device. And the only tuning I
did was set LIO's emulate_pr to 0 to avoid LIO's PR lock in the main IO
path which becomes an issue at around 12 jobs/virtqueues.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-17-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:14 -04:00
Mike Christie
c1ecd8e950 vhost: allow userspace to create workers
For vhost-scsi with 3 vqs or more and a workload that tries to use
them in parallel like:

fio --filename=/dev/sdb  --direct=1 --rw=randrw --bs=4k \
--ioengine=libaio --iodepth=128  --numjobs=3

the single vhost worker thread will become a bottlneck and we are stuck
at around 500K IOPs no matter how many jobs, virtqueues, and CPUs are
used.

To better utilize virtqueues and available CPUs, this patch allows
userspace to create workers and bind them to vqs. You can have N workers
per dev and also share N workers with M vqs on that dev.

This patch adds the interface related code and the next patch will hook
vhost-scsi into it. The patches do not try to hook net and vsock into
the interface because:

1. multiple workers don't seem to help vsock. The problem is that with
only 2 virtqueues we never fully use the existing worker when doing
bidirectional tests. This seems to match vhost-scsi where we don't see
the worker as a bottleneck until 3 virtqueues are used.

2. net already has a way to use multiple workers.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-16-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:14 -04:00
Mike Christie
1cdaafa1b8 vhost: replace single worker pointer with xarray
The next patch allows userspace to create multiple workers per device,
so this patch replaces the vhost_worker pointer with an xarray so we
can store mupltiple workers and look them up.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-15-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:14 -04:00
Mike Christie
cef25866f4 vhost: add helper to parse userspace vring state/file
The next patches add new vhost worker ioctls which will need to get a
vhost_virtqueue from a userspace struct which specifies the vq's index.
This moves the vhost_vring_ioctl code to do this to a helper so it can
be shared.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-14-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:14 -04:00
Mike Christie
27eca18911 vhost: remove vhost_work_queue
vhost_work_queue is no longer used. Each driver is using the poll or vq
based queueing, so remove vhost_work_queue.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-13-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:14 -04:00
Mike Christie
0a3eac5239 vhost_scsi: flush IO vqs then send TMF rsp
With one worker we will always send the scsi cmd responses then send the
TMF rsp, because LIO will always complete the scsi cmds first then call
into us to send the TMF response.

With multiple workers, the IO vq workers could be running while the
TMF/ctl vq worker is running so this has us do a flush before completing
the TMF to make sure cmds are completed when it's work is later queued
and run.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-12-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:14 -04:00
Mike Christie
78af31cc4e vhost_scsi: convert to vhost_vq_work_queue
Convert from vhost_work_queue to vhost_vq_work_queue so we can
remove vhost_work_queue.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-11-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:13 -04:00
Mike Christie
48ae70dd4d vhost_scsi: make SCSI cmd completion per vq
This patch separates the scsi cmd completion code paths so we can complete
cmds based on their vq instead of having all cmds complete on the same
worker/CPU. This will be useful with the next patches that allow us to
create mulitple worker threads and bind them to different vqs, and we can
have completions running on different threads/CPUs.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230626232307.97930-10-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:13 -04:00
Mike Christie
9e09d0ec2b vhost_sock: convert to vhost_vq_work_queue
Convert from vhost_work_queue to vhost_vq_work_queue, so we can drop
vhost_work_queue.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-9-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:13 -04:00
Mike Christie
493b94bf5a vhost: convert poll work to be vq based
This has the drivers pass in their poll to vq mapping and then converts
the core poll code to use the vq based helpers. In the next patches we
will allow vqs to be handled by different workers, so to allow drivers
to execute operations like queue, stop, flush, etc on specific polls/vqs
we need to know the mappings.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-8-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:13 -04:00
Mike Christie
a6fc04739b vhost: take worker or vq for flushing
This patch has the core work flush function take a worker. When we
support multiple workers we can then flush each worker during device
removal, stoppage, etc. It also adds a helper to flush specific
virtqueues, so vhost-scsi can flush IO vqs from it's ctl vq.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-7-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:13 -04:00
Mike Christie
0921dddcb5 vhost: take worker or vq instead of dev for queueing
This patch has the core work queueing function take a worker for when we
support multiple workers. It also adds a helper that takes a vq during
queueing so modules can control which vq/worker to queue work on.

This temp leaves vhost_work_queue. It will be removed when the drivers
are converted in the next patches.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-6-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:13 -04:00
Mike Christie
9784df151a vhost, vhost_net: add helper to check if vq has work
In the next patches each vq might have different workers so one could
have work but others do not. For net, we only want to check specific vqs,
so this adds a helper to check if a vq has work pending and converts
vhost-net to use it.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230626232307.97930-5-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:13 -04:00
Mike Christie
737bdb643c vhost: add vhost_worker pointer to vhost_virtqueue
This patchset allows userspace to map vqs to different workers. This
patch adds a worker pointer to the vq so in later patches in this set
we can queue/flush specific vqs and their workers.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-4-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:13 -04:00
Mike Christie
c011bb669d vhost: dynamically allocate vhost_worker
This patchset allows us to allocate multiple workers, so this has us
move from the vhost_worker that's embedded in the vhost_dev to
dynamically allocating it.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-3-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:13 -04:00
Mike Christie
3e11c6eb6a vhost: create worker at end of vhost_dev_set_owner
vsock can start queueing work after VHOST_VSOCK_SET_GUEST_CID, so
after we have called vhost_worker_create it can be calling
vhost_work_queue and trying to access the vhost worker/task. If
vhost_dev_alloc_iovecs fails, then vhost_worker_free could free
the worker/task from under vsock.

This moves vhost_worker_create to the end of vhost_dev_set_owner
where we know we can no longer fail in that path. If it fails
after the VHOST_SET_OWNER and userspace closes the device, then
the normal vsock release handling will do the right thing.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-2-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-07-03 12:15:13 -04:00
Linus Torvalds
6e17c6de3d - Yosry Ahmed brought back some cgroup v1 stats in OOM logs.
- Yosry has also eliminated cgroup's atomic rstat flushing.
 
 - Nhat Pham adds the new cachestat() syscall.  It provides userspace
   with the ability to query pagecache status - a similar concept to
   mincore() but more powerful and with improved usability.
 
 - Mel Gorman provides more optimizations for compaction, reducing the
   prevalence of page rescanning.
 
 - Lorenzo Stoakes has done some maintanance work on the get_user_pages()
   interface.
 
 - Liam Howlett continues with cleanups and maintenance work to the maple
   tree code.  Peng Zhang also does some work on maple tree.
 
 - Johannes Weiner has done some cleanup work on the compaction code.
 
 - David Hildenbrand has contributed additional selftests for
   get_user_pages().
 
 - Thomas Gleixner has contributed some maintenance and optimization work
   for the vmalloc code.
 
 - Baolin Wang has provided some compaction cleanups,
 
 - SeongJae Park continues maintenance work on the DAMON code.
 
 - Huang Ying has done some maintenance on the swap code's usage of
   device refcounting.
 
 - Christoph Hellwig has some cleanups for the filemap/directio code.
 
 - Ryan Roberts provides two patch series which yield some
   rationalization of the kernel's access to pte entries - use the provided
   APIs rather than open-coding accesses.
 
 - Lorenzo Stoakes has some fixes to the interaction between pagecache
   and directio access to file mappings.
 
 - John Hubbard has a series of fixes to the MM selftesting code.
 
 - ZhangPeng continues the folio conversion campaign.
 
 - Hugh Dickins has been working on the pagetable handling code, mainly
   with a view to reducing the load on the mmap_lock.
 
 - Catalin Marinas has reduced the arm64 kmalloc() minimum alignment from
   128 to 8.
 
 - Domenico Cerasuolo has improved the zswap reclaim mechanism by
   reorganizing the LRU management.
 
 - Matthew Wilcox provides some fixups to make gfs2 work better with the
   buffer_head code.
 
 - Vishal Moola also has done some folio conversion work.
 
 - Matthew Wilcox has removed the remnants of the pagevec code - their
   functionality is migrated over to struct folio_batch.
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Merge tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull mm updates from Andrew Morton:

 - Yosry Ahmed brought back some cgroup v1 stats in OOM logs

 - Yosry has also eliminated cgroup's atomic rstat flushing

 - Nhat Pham adds the new cachestat() syscall. It provides userspace
   with the ability to query pagecache status - a similar concept to
   mincore() but more powerful and with improved usability

 - Mel Gorman provides more optimizations for compaction, reducing the
   prevalence of page rescanning

 - Lorenzo Stoakes has done some maintanance work on the
   get_user_pages() interface

 - Liam Howlett continues with cleanups and maintenance work to the
   maple tree code. Peng Zhang also does some work on maple tree

 - Johannes Weiner has done some cleanup work on the compaction code

 - David Hildenbrand has contributed additional selftests for
   get_user_pages()

 - Thomas Gleixner has contributed some maintenance and optimization
   work for the vmalloc code

 - Baolin Wang has provided some compaction cleanups,

 - SeongJae Park continues maintenance work on the DAMON code

 - Huang Ying has done some maintenance on the swap code's usage of
   device refcounting

 - Christoph Hellwig has some cleanups for the filemap/directio code

 - Ryan Roberts provides two patch series which yield some
   rationalization of the kernel's access to pte entries - use the
   provided APIs rather than open-coding accesses

 - Lorenzo Stoakes has some fixes to the interaction between pagecache
   and directio access to file mappings

 - John Hubbard has a series of fixes to the MM selftesting code

 - ZhangPeng continues the folio conversion campaign

 - Hugh Dickins has been working on the pagetable handling code, mainly
   with a view to reducing the load on the mmap_lock

 - Catalin Marinas has reduced the arm64 kmalloc() minimum alignment
   from 128 to 8

 - Domenico Cerasuolo has improved the zswap reclaim mechanism by
   reorganizing the LRU management

 - Matthew Wilcox provides some fixups to make gfs2 work better with the
   buffer_head code

 - Vishal Moola also has done some folio conversion work

 - Matthew Wilcox has removed the remnants of the pagevec code - their
   functionality is migrated over to struct folio_batch

* tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (380 commits)
  mm/hugetlb: remove hugetlb_set_page_subpool()
  mm: nommu: correct the range of mmap_sem_read_lock in task_mem()
  hugetlb: revert use of page_cache_next_miss()
  Revert "page cache: fix page_cache_next/prev_miss off by one"
  mm/vmscan: fix root proactive reclaim unthrottling unbalanced node
  mm: memcg: rename and document global_reclaim()
  mm: kill [add|del]_page_to_lru_list()
  mm: compaction: convert to use a folio in isolate_migratepages_block()
  mm: zswap: fix double invalidate with exclusive loads
  mm: remove unnecessary pagevec includes
  mm: remove references to pagevec
  mm: rename invalidate_mapping_pagevec to mapping_try_invalidate
  mm: remove struct pagevec
  net: convert sunrpc from pagevec to folio_batch
  i915: convert i915_gpu_error to use a folio_batch
  pagevec: rename fbatch_count()
  mm: remove check_move_unevictable_pages()
  drm: convert drm_gem_put_pages() to use a folio_batch
  i915: convert shmem_sg_free_table() to use a folio_batch
  scatterlist: add sg_set_folio()
  ...
2023-06-28 10:28:11 -07:00
Lorenzo Stoakes
4c630f3074 mm/gup: remove vmas parameter from pin_user_pages()
We are now in a position where no caller of pin_user_pages() requires the
vmas parameter at all, so eliminate this parameter from the function and
all callers.

This clears the way to removing the vmas parameter from GUP altogether.

Link: https://lkml.kernel.org/r/195a99ae949c9f5cb589d2222b736ced96ec199a.1684350871.git.lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>	[qib]
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>	[drivers/media]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 16:25:26 -07:00
Shannon Nelson
beee7fdb5b vhost_vdpa: support PACKED when setting-getting vring_base
Use the right structs for PACKED or split vqs when setting and
getting the vring base.

Fixes: 4c8cf31885 ("vhost: introduce vDPA-based backend")
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Message-Id: <20230424225031.18947-4-shannon.nelson@amd.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2023-06-09 12:08:04 -04:00
Shannon Nelson
55d8122f5c vhost: support PACKED when setting-getting vring_base
Use the right structs for PACKED or split vqs when setting and
getting the vring base.

Fixes: 4c8cf31885 ("vhost: introduce vDPA-based backend")
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Message-Id: <20230424225031.18947-3-shannon.nelson@amd.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2023-06-09 12:07:52 -04:00
Mike Christie
4b13cbef79 vhost: Fix worker hangs due to missed wake up calls
We can race where we have added work to the work_list, but
vhost_task_fn has passed that check but not yet set us into
TASK_INTERRUPTIBLE. wake_up_process will see us in TASK_RUNNING and
just return.

This bug was intoduced in commit f9010dbdce ("fork, vhost: Use
CLONE_THREAD to fix freezer/ps regression") when I moved the setting
of TASK_INTERRUPTIBLE to simplfy the code and avoid get_signal from
logging warnings about being in the wrong state. This moves the setting
of TASK_INTERRUPTIBLE back to before we test if we need to stop the
task to avoid a possible race there as well. We then have vhost_worker
set TASK_RUNNING if it finds work similar to before.

Fixes: f9010dbdce ("fork, vhost: Use CLONE_THREAD to fix freezer/ps regression")
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230607192338.6041-3-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-06-08 15:43:09 -04:00
Mike Christie
a284f09eff vhost: Fix crash during early vhost_transport_send_pkt calls
If userspace does VHOST_VSOCK_SET_GUEST_CID before VHOST_SET_OWNER we
can race where:
1. thread0 calls vhost_transport_send_pkt -> vhost_work_queue
2. thread1 does VHOST_SET_OWNER which calls vhost_worker_create.
3. vhost_worker_create will set the dev->worker pointer before setting
the worker->vtsk pointer.
4. thread0's vhost_work_queue will see the dev->worker pointer is
set and try to call vhost_task_wake using not yet set worker->vtsk
pointer.
5. We then crash since vtsk is NULL.

Before commit 6e890c5d50 ("vhost: use vhost_tasks for worker
threads"), we only had the worker pointer so we could just check it to
see if VHOST_SET_OWNER has been done. After that commit we have the
vhost_worker and vhost_task pointer, so we can now hit the bug above.

This patch embeds the vhost_worker in the vhost_dev and moves the work
list initialization back to vhost_dev_init, so we can just check the
worker.vtsk pointer to check if VHOST_SET_OWNER has been done like
before.

Fixes: 6e890c5d50 ("vhost: use vhost_tasks for worker threads")
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230607192338.6041-2-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reported-by: syzbot+d0d442c22fa8db45ff0e@syzkaller.appspotmail.com
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
2023-06-08 15:43:09 -04:00
Andrey Smetanin
1f5d2e3bab vhost_net: revert upend_idx only on retriable error
Fix possible virtqueue used buffers leak and corresponding stuck
in case of temporary -EIO from sendmsg() which is produced by
tun driver while backend device is not up.

In case of no-retriable error and zcopy do not revert upend_idx
to pass packet data (that is update used_idx in corresponding
vhost_zerocopy_signal_used()) as if packet data has been
transferred successfully.

v2: set vq->heads[ubuf->desc].len equal to VHOST_DMA_DONE_LEN
in case of fake successful transmit.

Signed-off-by: Andrey Smetanin <asmetanin@yandex-team.ru>
Message-Id: <20230424204411.24888-1-asmetanin@yandex-team.ru>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Andrey Smetanin <asmetanin@yandex-team.ru>
Acked-by: Jason Wang <jasowang@redhat.com>
2023-06-08 15:43:08 -04:00
Shannon Nelson
376daf3177 vhost_vdpa: tell vqs about the negotiated
As is done in the net, iscsi, and vsock vhost support, let the vdpa vqs
know about the features that have been negotiated.  This allows vhost
to more safely make decisions based on the features, such as when using
PACKED vs split queues.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230424225031.18947-2-shannon.nelson@amd.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-06-08 15:43:08 -04:00
Prathu Baronia
4d8df0f5f7 vhost: use kzalloc() instead of kmalloc() followed by memset()
Use kzalloc() to allocate new zeroed out msg node instead of
memsetting a node allocated with kmalloc().

Signed-off-by: Prathu Baronia <prathubaronia2011@gmail.com>
Message-Id: <20230522085019.42914-1-prathubaronia2011@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
2023-06-07 16:22:30 -04:00
Mike Christie
f9010dbdce fork, vhost: Use CLONE_THREAD to fix freezer/ps regression
When switching from kthreads to vhost_tasks two bugs were added:
1. The vhost worker tasks's now show up as processes so scripts doing
ps or ps a would not incorrectly detect the vhost task as another
process.  2. kthreads disabled freeze by setting PF_NOFREEZE, but
vhost tasks's didn't disable or add support for them.

To fix both bugs, this switches the vhost task to be thread in the
process that does the VHOST_SET_OWNER ioctl, and has vhost_worker call
get_signal to support SIGKILL/SIGSTOP and freeze signals. Note that
SIGKILL/STOP support is required because CLONE_THREAD requires
CLONE_SIGHAND which requires those 2 signals to be supported.

This is a modified version of the patch written by Mike Christie
<michael.christie@oracle.com> which was a modified version of patch
originally written by Linus.

Much of what depended upon PF_IO_WORKER now depends on PF_USER_WORKER.
Including ignoring signals, setting up the register state, and having
get_signal return instead of calling do_group_exit.

Tidied up the vhost_task abstraction so that the definition of
vhost_task only needs to be visible inside of vhost_task.c.  Making
it easier to review the code and tell what needs to be done where.
As part of this the main loop has been moved from vhost_worker into
vhost_task_fn.  vhost_worker now returns true if work was done.

The main loop has been updated to call get_signal which handles
SIGSTOP, freezing, and collects the message that tells the thread to
exit as part of process exit.  This collection clears
__fatal_signal_pending.  This collection is not guaranteed to
clear signal_pending() so clear that explicitly so the schedule()
sleeps.

For now the vhost thread continues to exist and run work until the
last file descriptor is closed and the release function is called as
part of freeing struct file.  To avoid hangs in the coredump
rendezvous and when killing threads in a multi-threaded exec.  The
coredump code and de_thread have been modified to ignore vhost threads.

Remvoing the special case for exec appears to require teaching
vhost_dev_flush how to directly complete transactions in case
the vhost thread is no longer running.

Removing the special case for coredump rendezvous requires either the
above fix needed for exec or moving the coredump rendezvous into
get_signal.

Fixes: 6e890c5d50 ("vhost: use vhost_tasks for worker threads")
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Co-developed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-06-01 17:15:33 -04:00
Linus Torvalds
586b222d74 Scheduler changes for v6.4:
- Allow unprivileged PSI poll()ing
 
  - Fix performance regression introduced by mm_cid
 
  - Improve livepatch stalls by adding livepatch task switching to cond_resched(),
    this resolves livepatching busy-loop stalls with certain CPU-bound kthreads.
 
  - Improve sched_move_task() performance on autogroup configs.
 
  - On core-scheduling CPUs, avoid selecting throttled tasks to run
 
  - Misc cleanups, fixes and improvements.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'sched-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:

 - Allow unprivileged PSI poll()ing

 - Fix performance regression introduced by mm_cid

 - Improve livepatch stalls by adding livepatch task switching to
   cond_resched(). This resolves livepatching busy-loop stalls with
   certain CPU-bound kthreads

 - Improve sched_move_task() performance on autogroup configs

 - On core-scheduling CPUs, avoid selecting throttled tasks to run

 - Misc cleanups, fixes and improvements

* tag 'sched-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/clock: Fix local_clock() before sched_clock_init()
  sched/rt: Fix bad task migration for rt tasks
  sched: Fix performance regression introduced by mm_cid
  sched/core: Make sched_dynamic_mutex static
  sched/psi: Allow unprivileged polling of N*2s period
  sched/psi: Extract update_triggers side effect
  sched/psi: Rename existing poll members in preparation
  sched/psi: Rearrange polling code in preparation
  sched/fair: Fix inaccurate tally of ttwu_move_affine
  vhost: Fix livepatch timeouts in vhost_worker()
  livepatch,sched: Add livepatch task switching to cond_resched()
  livepatch: Skip task_call_func() for current task
  livepatch: Convert stack entries array to percpu
  sched: Interleave cfs bandwidth timers for improved single thread performance at low utilization
  sched/core: Reduce cost of sched_move_task when config autogroup
  sched/core: Avoid selecting the task that is throttled to run when core-sched enable
  sched/topology: Make sched_energy_mutex,update static
2023-04-28 14:53:30 -07:00