IF YOU WOULD LIKE TO GET AN ACCOUNT, please write an
email to Administrator. User accounts are meant only to access repo
and report issues and/or generate pull requests.
This is a purpose-specific Git hosting for
BaseALT
projects. Thank you for your understanding!
Только зарегистрированные пользователи имеют доступ к сервису!
Для получения аккаунта, обратитесь к администратору.
Sync device with CPU pages upon ODP MR registration. mlx5 already has to
zero the HW's version of the PAS list, may as well deliver a PAS list that
matches the current CPU page tables configuration.
Link: https://lore.kernel.org/r/20200930163828.1336747-5-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Extend advice MR to support non faulting mode, this can improve
performance by increasing the populated page tables in the device.
Link: https://lore.kernel.org/r/20200930163828.1336747-4-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Enable ODP sync without faulting, this improves performance by reducing
the number of page faults in the system.
The gain from this option is that the device page table can be aligned
with the presented pages in the CPU page table without causing page
faults.
As of that, the overhead on data path from hardware point of view to
trigger a fault which end-up by calling the driver to bring the pages
will be dropped.
Link: https://lore.kernel.org/r/20200930163828.1336747-3-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Move to use hmm_range_fault() instead of get_user_pags_remote() to improve
performance in a few aspects:
This includes:
- Dropping the need to allocate and free memory to hold its output
- No need any more to use put_page() to unpin the pages
- The logic to detect contiguous pages is done based on the returned
order, no need to run per page and evaluate.
In addition, moving to use hmm_range_fault() enables to reduce page faults
in the system with it's snapshot mode, this will be introduced in next
patches from this series.
As part of this, cleanup some flows and use the required data structures
to work with hmm_range_fault().
Link: https://lore.kernel.org/r/20200930163828.1336747-2-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Once a mkey is created it can be modified using UMR. This is desirable for
performance reasons. However, different hardware has restrictions on what
modifications are possible using UMR. Make sense of these checks:
- mlx5_ib_can_reconfig_with_umr() returns true if the access flags can be
altered. Most cases create MRs using 0 access flags (now made clear by
consistent use of set_mkc_access_pd_addr_fields()), but the old logic
here was tormented. Make it clear that this is checking if the current
access_flags can be modified using UMR to different access_flags. It is
always OK to use UMR to change flags that all HW supports.
- mlx5_ib_can_load_pas_with_umr() returns true if UMR can be used to
enable and update the PAS/XLT. Enabling requires updating the entity
size, so UMR ends up completely disabled on this old hardware. Make it
clear why it is disabled. FRWR, ODP and cache always requires
mlx5_ib_can_load_pas_with_umr().
- mlx5_ib_pas_fits_in_mr() is used to tell if an existing MR can be
resized to hold a new PAS list. This only works for cached MR's because
we don't store the PAS list size in other cases.
To be very clear, arrange things so any pre-created MR's in the cache
check the newly requested access_flags before allowing the MR to leave the
cache. If UMR cannot set the required access_flags the cache fails to
create the MR.
This in turn means relaxed ordering and atomic are now correctly blocked
early for implicit ODP on older HW.
Link: https://lore.kernel.org/r/20200914112653.345244-6-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Smaller set of RDMA updates. A smaller number of 'big topics' with the
majority of changes being driver updates.
- Driver updates for hfi1, rxe, mlx5, hns, qedr, usnic, bnxt_re
- Removal of dead or redundant code across the drivers
- RAW resource tracker dumps to include a device specific data blob for
device objects to aide device debugging
- Further advance the IOCTL interface, remove the ability to turn it off.
Add QUERY_CONTEXT, QUERY_MR, and QUERY_PD commands
- Remove stubs related to devices with no pkey table
- A shared CQ scheme to allow multiple ULPs to share the CQ rings of a
device to give higher performance
- Several more static checker, syzkaller and rare crashers fixed
-----BEGIN PGP SIGNATURE-----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=0z2L
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull rdma updates from Jason Gunthorpe:
"A quiet cycle after the larger 5.8 effort. Substantially cleanup and
driver work with a few smaller features this time.
- Driver updates for hfi1, rxe, mlx5, hns, qedr, usnic, bnxt_re
- Removal of dead or redundant code across the drivers
- RAW resource tracker dumps to include a device specific data blob
for device objects to aide device debugging
- Further advance the IOCTL interface, remove the ability to turn it
off. Add QUERY_CONTEXT, QUERY_MR, and QUERY_PD commands
- Remove stubs related to devices with no pkey table
- A shared CQ scheme to allow multiple ULPs to share the CQ rings of
a device to give higher performance
- Several more static checker, syzkaller and rare crashers fixed"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (121 commits)
RDMA/mlx5: Fix flow destination setting for RDMA TX flow table
RDMA/rxe: Remove pkey table
RDMA/umem: Add a schedule point in ib_umem_get()
RDMA/hns: Fix the unneeded process when getting a general type of CQE error
RDMA/hns: Fix error during modify qp RTS2RTS
RDMA/hns: Delete unnecessary memset when allocating VF resource
RDMA/hns: Remove redundant parameters in set_rc_wqe()
RDMA/hns: Remove support for HIP08_A
RDMA/hns: Refactor hns_roce_v2_set_hem()
RDMA/hns: Remove redundant hardware opcode definitions
RDMA/netlink: Remove CAP_NET_RAW check when dump a raw QP
RDMA/include: Replace license text with SPDX tags
RDMA/rtrs: remove WQ_MEM_RECLAIM for rtrs_wq
RDMA/rtrs-clt: add an additional random 8 seconds before reconnecting
RDMA/cma: Execute rdma_cm destruction from a handler properly
RDMA/cma: Remove unneeded locking for req paths
RDMA/cma: Using the standard locking pattern when delivering the removal event
RDMA/cma: Simplify DEVICE_REMOVAL for internal_id
RDMA/efa: Add EFA 0xefa1 PCI ID
RDMA/efa: User/kernel compatibility handshake mechanism
...
destroy_prefetch_work() must always be called if the work is not going
to be queued. The num_sge also should have been set to i, not i-1
which avoids the condition where it shouldn't have been called in the
first place.
Cc: stable@vger.kernel.org
Fixes: fb985e278a30 ("RDMA/mlx5: Use SRCU properly in ODP prefetch")
Link: https://lore.kernel.org/r/20200727095712.495652-1-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Prefetch work in mlx5_ib_prefetch_mr_work can be queued and able to run
concurrently with destruction of the implicit MR. The num_deferred_work
was intended to serialize this, but there is a race:
CPU0 CPU1
mlx5_ib_free_implicit_mr()
xa_erase(odp_mkeys)
synchronize_srcu()
__xa_erase(implicit_children)
mlx5_ib_prefetch_mr_work()
pagefault_mr()
pagefault_implicit_mr()
implicit_get_child_mr()
xa_cmpxchg()
atomic_dec_and_test(num_deferred_mr)
wait_event(imr->q_deferred_work)
ib_umem_odp_release(odp_imr)
kfree(odp_imr)
At this point in mlx5_ib_free_implicit_mr() the implicit_children list is
supposed to be empty forever so that destroy_unused_implicit_child_mr()
and related are not and will not be running.
Since it is not empty the destroy_unused_implicit_child_mr() flow ends up
touching deallocated memory as mlx5_ib_free_implicit_mr() already tore down the
imr parent.
The solution is to flush out the prefetch wq by driving num_deferred_work
to zero after creation of new prefetch work is blocked.
Fixes: 5256edcb98a1 ("RDMA/mlx5: Rework implicit ODP destroy")
Link: https://lore.kernel.org/r/20200719065435.130722-1-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
For debugging purpose it will be easier to understand if prefetch works
okay if it has its own counter. Introduce ODP prefetch counter and count
per MR the total number of prefetched pages.
In addition remove comment which is not relevant anymore and anyway not in
the correct place.
Link: https://lore.kernel.org/r/20200621104147.53795-1-leon@kernel.org
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reuse newly introduced mlx5_cmd_exec_in() and mlx5_cmd_exec_inout() to
reduce code duplication in mlx5_ib module.
Link: https://lore.kernel.org/r/20200506065513.4668-2-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
QP type is stored in the IB/core QP struct, but it doesn't have all the
needed information, like internal QP type used in the driver itself.
Update mlx5_ib to have cached QP type which includes both IBTA and
Mellanox specific one.
Such change allows us to make even further cleanup of QP creation flow.
Link: https://lore.kernel.org/r/20200427154636.381474-21-leon@kernel.org
Reviewed-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
MLX5_QP_FLAG_SIGNATURE is exposed to the users but in the kernel
the create_qp flow treated it differently from other MLX5_QP_FLAG_*s.
Fix it by ditching wq_sig boolean variable and use general flag_en
mechanism.
Link: https://lore.kernel.org/r/20200427154636.381474-16-leon@kernel.org
Reviewed-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The mlx5_core doesn't need any functionality coded in qp.c, so move
that file to drivers/infiniband/ be under mlx5_ib responsibility.
Reviewed-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Leon Romanovsky says:
====================
This series fixes various corner cases in the mlx5_ib MR cache
implementation, see specific commit messages for more information.
====================
Based on the mlx5-next branch at
git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux
Due to dependencies
* branch 'mlx5_mr-cache':
RDMA/mlx5: Allow MRs to be created in the cache synchronously
RDMA/mlx5: Revise how the hysteresis scheme works for cache filling
RDMA/mlx5: Fix locking in MR cache work queue
RDMA/mlx5: Lock access to ent->available_mrs/limit when doing queue_work
RDMA/mlx5: Fix MR cache size and limit debugfs
RDMA/mlx5: Always remove MRs from the cache before destroying them
RDMA/mlx5: Simplify how the MR cache bucket is located
RDMA/mlx5: Rename the tracking variables for the MR cache
RDMA/mlx5: Replace spinlock protected write with atomic var
{IB,net}/mlx5: Move asynchronous mkey creation to mlx5_ib
{IB,net}/mlx5: Assign mkey variant in mlx5_ib only
{IB,net}/mlx5: Setup mkey variant before mr create command invocation
There are many bad APIs here that are accepting a cache bucket index
instead of a bucket pointer. Many of the callers already have a bucket
pointer, so this results in a lot of confusing uses of order2idx().
Pass the struct mlx5_cache_ent into add_keys(), remove_keys(), and
alloc_cached_mr().
Once the MR is in the cache, store the cache bucket pointer directly in
the MR, replacing the 'bool allocated_from cache'.
In the end there is only one place that needs to form index from order,
alloc_mr_from_cache(). Increase the safety of this function by disallowing
it from accessing cache entries in the ODP special area.
Link: https://lore.kernel.org/r/20200310082238.239865-7-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Following race may occur because of the call_srcu and the placement of
the synchronize_srcu vs the xa_erase.
CPU0 CPU1
mlx5_ib_free_implicit_mr: destroy_unused_implicit_child_mr:
xa_erase(odp_mkeys)
synchronize_srcu()
xa_lock(implicit_children)
if (still in xarray)
atomic_inc()
call_srcu()
xa_unlock(implicit_children)
xa_erase(implicit_children):
xa_lock(implicit_children)
__xa_erase()
xa_unlock(implicit_children)
flush_workqueue()
[..]
free_implicit_child_mr_rcu:
(via call_srcu)
queue_work()
WARN_ON(atomic_read())
[..]
free_implicit_child_mr_work:
(via wq)
free_implicit_child_mr()
mlx5_mr_cache_invalidate()
mlx5_ib_update_xlt() <-- UMR QP fail
atomic_dec()
The wait_event() solves the race because it blocks until
free_implicit_child_mr_work() completes.
Fixes: 5256edcb98a1 ("RDMA/mlx5: Rework implicit ODP destroy")
Link: https://lore.kernel.org/r/20200227113918.94432-1-leon@kernel.org
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The following series extends MR creation routines to allow creation of
user MRs through kernel ULPs as a proxy. The immediate use case is to
allow RDS to work over FS-DAX, which requires ODP (on-demand-paging)
MRs to be created and such MRs were not possible to create prior this
series.
The first part of this patchset extends RDMA to have special verb
ib_reg_user_mr(). The common use case that uses this function is a
userspace application that allocates memory for HCA access but the
responsibility to register the memory at the HCA is on an kernel ULP.
This ULP acts as an agent for the userspace application.
The second part provides advise MR functionality for ULPs. This is
integral part of ODP flows and used to trigger pagefaults in advance
to prepare memory before running working set.
The third part is actual user of those in-kernel APIs.
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQT1m3YD37UfMCUQBNwp8NhrnBAZsQUCXiVO8AAKCRAp8NhrnBAZ
scTrAP9gb0d3qv0IOtHw5aGI1DAgjTUn/SzUOnsjDEn7DIoh9gEA2+ZmaEyLXKrl
+UcZb31auy5P8ueJYokRLhLAyRcOIAg=
=yaHb
-----END PGP SIGNATURE-----
Merge tag 'rds-odp-for-5.5' into rdma.git for-next
From https://git.kernel.org/pub/scm/linux/kernel/git/leon/linux-rdma
Leon Romanovsky says:
====================
Use ODP MRs for kernel ULPs
The following series extends MR creation routines to allow creation of
user MRs through kernel ULPs as a proxy. The immediate use case is to
allow RDS to work over FS-DAX, which requires ODP (on-demand-paging)
MRs to be created and such MRs were not possible to create prior this
series.
The first part of this patchset extends RDMA to have special verb
ib_reg_user_mr(). The common use case that uses this function is a
userspace application that allocates memory for HCA access but the
responsibility to register the memory at the HCA is on an kernel ULP.
This ULP acts as an agent for the userspace application.
The second part provides advise MR functionality for ULPs. This is
integral part of ODP flows and used to trigger pagefaults in advance
to prepare memory before running working set.
The third part is actual user of those in-kernel APIs.
====================
* tag 'rds-odp-for-5.5':
net/rds: Use prefetch for On-Demand-Paging MR
net/rds: Handle ODP mr registration/unregistration
net/rds: Detect need of On-Demand-Paging memory registration
RDMA/mlx5: Fix handling of IOVA != user_va in ODP paths
IB/mlx5: Mask out unsupported ODP capabilities for kernel QPs
RDMA/mlx5: Don't fake udata for kernel path
IB/mlx5: Add ODP WQE handlers for kernel QPs
IB/core: Add interface to advise_mr for kernel users
IB/core: Introduce ib_reg_user_mr
IB: Allow calls to ib_umem_get from kernel ULPs
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Enable relaxed ordering in the mkey context when requested. As relaxed
ordering is not currently supported in UMR, disable UMR usage for relaxed
ordering MRs.
Link: https://lore.kernel.org/r/1578506740-22188-11-git-send-email-yishaih@mellanox.com
Signed-off-by: Michael Guralnik <michaelgur@mellanox.com>
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Till recently it was not possible for userspace to specify a different
IOVA, but with the new ibv_reg_mr_iova() library call this can be done.
To compute the user_va we must compute:
user_va = (iova - iova_start) + user_va_start
while being cautious of overflow and other math problems.
The iova is not reliably stored in the mmkey when the MR is created. Only
the cached creation path (the common one) set it, so it must also be set
when creating uncached MRs.
Fix the weird use of iova when computing the starting page index in the
MR. In the normal case, when iova == umem.address:
iova & (~(BIT(page_shift) - 1)) ==
ALIGN_DOWN(umem.address, odp->page_size) ==
ib_umem_start(odp)
And when iova is different using it in math with a user_va is wrong.
Finally, do not allow an implicit ODP to be created with a non-zero IOVA
as we have no support for that.
Fixes: 7bdf65d411c1 ("IB/mlx5: Handle page faults")
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
One of the steps in ODP page fault handler for WQEs is to read a WQE
from a QP send queue or receive queue buffer at a specific index.
Since the implementation of this buffer is different between kernel and
user QP the implementation of the handler needs to be aware of that and
handle it in a different way.
ODP for kernel MRs is currently supported only for RDMA_READ
and RDMA_WRITE operations so change the handler to
- read a WQE from a kernel QP send queue
- fail if access to receive queue or shared receive queue is
required for a kernel QP
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
So far the assumption was that ib_umem_get() and ib_umem_odp_get()
are called from flows that start in UVERBS and therefore has a user
context. This assumption restricts flows that are initiated by ULPs
and need the service that ib_umem_get() provides.
This patch changes ib_umem_get() and ib_umem_odp_get() to get IB device
directly by relying on the fact that both UVERBS and ULPs sets that
field correctly.
Reviewed-by: Guy Levi <guyle@mellanox.com>
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Building MR translation table in the ODP case requires additional
flexibility, namely random access to DMA addresses. Make both direct and
indirect ODP MR use same code path, separated from the non-ODP MR code
path.
With the restructuring the correct page_shift is now used around
__mlx5_ib_populate_pas().
Fixes: d2183c6f1958 ("RDMA/umem: Move page_shift from ib_umem to ib_odp_umem")
Link: https://lore.kernel.org/r/20191222124649.52300-2-leon@kernel.org
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This is another round of bug fixing and cleanup. This time the focus is on
the driver pattern to use mmu notifiers to monitor a VA range. This code
is lifted out of many drivers and hmm_mirror directly into the
mmu_notifier core and written using the best ideas from all the driver
implementations.
This removes many bugs from the drivers and has a very pleasing
diffstat. More drivers can still be converted, but that is for another
cycle.
- A shared branch with RDMA reworking the RDMA ODP implementation
- New mmu_interval_notifier API. This is focused on the use case of
monitoring a VA and simplifies the process for drivers
- A common seq-count locking scheme built into the mmu_interval_notifier
API usable by drivers that call get_user_pages() or hmm_range_fault()
with the VA range
- Conversion of mlx5 ODP, hfi1, radeon, nouveau, AMD GPU, and Xen GntDev
drivers to the new API. This deletes a lot of wonky driver code.
- Two improvements for hmm_range_fault(), from testing done by Ralph
-----BEGIN PGP SIGNATURE-----
iQIzBAABCgAdFiEEfB7FMLh+8QxL+6i3OG33FX4gmxoFAl3cCjQACgkQOG33FX4g
mxpp8xAAiR9iOdT28m/tx1GF31XludrMhRZVIiz0vmCIxIiAkWekWEfAEVm9PDnh
wdrxTJohSs+B65AK3sfToOM3AIuNCuFVWmbbHI5qmOO76vaSvcZa905Z++pNsawO
Bn8mgRCprYoFHcxWLvTvnA5U0g1S2BSSOwBSZI43CbEnVvHjYAR6MnvRqfGMk+NF
bf8fTk/x+fl0DCemhynlBLuJkogzoE2Hgl0yPY5bFna4PktOxdpa1yPaQsiqZ7e6
2s2NtM3pbMBJk0W42q5BU+aPhiqfxFFszasPSLBduXrD2xDsG76HJdHj5VydKmfL
nelG4BvqJozXTEZWvTEePYhCqaZ41eJZ7Asw8BXtmacVqE5mDlTXo/Zdgbz7yEOR
mI5MVyjD5rauZJldUOWXbwrPoWVFRvboauehiSgqvxvT9HvlFp9GKObSuu4gubBQ
mzxs4t48tPhA7bswLmw0/pETSogFuVDfaB7hsyY0gi8EwxMFMpw2qFypm1PEEF+C
BuUxCSShzvNKrraNe5PWaNNFd3AzIwAOWJHE+poH4bCoXQVr5nA+rq2gnHkdY5vq
/xrBCyxkf0U05YoFGYembPVCInMehzp9Xjy8V+SueSvCg2/TYwGDCgGfsbe9dNOP
Bc40JpS7BDn5w9nyLUJmOx7jfruNV6kx1QslA7NDDrB/rzOlsEc=
=Hj8a
-----END PGP SIGNATURE-----
Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull hmm updates from Jason Gunthorpe:
"This is another round of bug fixing and cleanup. This time the focus
is on the driver pattern to use mmu notifiers to monitor a VA range.
This code is lifted out of many drivers and hmm_mirror directly into
the mmu_notifier core and written using the best ideas from all the
driver implementations.
This removes many bugs from the drivers and has a very pleasing
diffstat. More drivers can still be converted, but that is for another
cycle.
- A shared branch with RDMA reworking the RDMA ODP implementation
- New mmu_interval_notifier API. This is focused on the use case of
monitoring a VA and simplifies the process for drivers
- A common seq-count locking scheme built into the
mmu_interval_notifier API usable by drivers that call
get_user_pages() or hmm_range_fault() with the VA range
- Conversion of mlx5 ODP, hfi1, radeon, nouveau, AMD GPU, and Xen
GntDev drivers to the new API. This deletes a lot of wonky driver
code.
- Two improvements for hmm_range_fault(), from testing done by Ralph"
* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
mm/hmm: remove hmm_range_dma_map and hmm_range_dma_unmap
mm/hmm: make full use of walk_page_range()
xen/gntdev: use mmu_interval_notifier_insert
mm/hmm: remove hmm_mirror and related
drm/amdgpu: Use mmu_interval_notifier instead of hmm_mirror
drm/amdgpu: Use mmu_interval_insert instead of hmm_mirror
drm/amdgpu: Call find_vma under mmap_sem
nouveau: use mmu_interval_notifier instead of hmm_mirror
nouveau: use mmu_notifier directly for invalidate_range_start
drm/radeon: use mmu_interval_notifier_insert
RDMA/hfi1: Use mmu_interval_notifier_insert for user_exp_rcv
RDMA/odp: Use mmu_interval_notifier_insert()
mm/hmm: define the pre-processor related parts of hmm.h even if disabled
mm/hmm: allow hmm_range to be used with a mmu_interval_notifier or hmm_mirror
mm/mmu_notifier: add an interval tree notifier
mm/mmu_notifier: define the header pre-processor parts even if disabled
mm/hmm: allow snapshot of the special zero page
Replace the internal interval tree based mmu notifier with the new common
mmu_interval_notifier_insert() API. This removes a lot of code and fixes a
deadlock that can be triggered in ODP:
zap_page_range()
mmu_notifier_invalidate_range_start()
[..]
ib_umem_notifier_invalidate_range_start()
down_read(&per_mm->umem_rwsem)
unmap_single_vma()
[..]
__split_huge_page_pmd()
mmu_notifier_invalidate_range_start()
[..]
ib_umem_notifier_invalidate_range_start()
down_read(&per_mm->umem_rwsem) // DEADLOCK
mmu_notifier_invalidate_range_end()
up_read(&per_mm->umem_rwsem)
mmu_notifier_invalidate_range_end()
up_read(&per_mm->umem_rwsem)
The umem_rwsem is held across the range_start/end as the ODP algorithm for
invalidate_range_end cannot tolerate changes to the interval
tree. However, due to the nested invalidation regions the second
down_read() can deadlock if there are competing writers. The new core code
provides an alternative scheme to solve this problem.
Fixes: ca748c39ea3f ("RDMA/umem: Get rid of per_mm->notifier_count")
Link: https://lore.kernel.org/r/20191112202231.3856-6-jgg@ziepe.ca
Tested-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Jason Gunthorpe says:
====================
In order to hoist the interval tree code out of the drivers and into the
mmu_notifiers it is necessary for the drivers to not use the interval tree
for other things.
This series replaces the interval tree with an xarray and along the way
re-aligns all the locking to use a sensible SRCU model where the 'update'
step is done by modifying an xarray.
The result is overall much simpler and with less locking in the critical
path. Many functions were reworked for clarity and small details like
using 'imr' to refer to the implicit MR make the entire code flow here
more readable.
This also squashes at least two race bugs on its own, and quite possibily
more that haven't been identified.
====================
Merge conflicts with the odp statistics patch resolved.
* branch 'odp_rework':
RDMA/odp: Remove broken debugging call to invalidate_range
RDMA/mlx5: Do not race with mlx5_ib_invalidate_range during create and destroy
RDMA/mlx5: Do not store implicit children in the odp_mkeys xarray
RDMA/mlx5: Rework implicit ODP destroy
RDMA/mlx5: Avoid double lookups on the pagefault path
RDMA/mlx5: Reduce locking in implicit_mr_get_data()
RDMA/mlx5: Use an xarray for the children of an implicit ODP
RDMA/mlx5: Split implicit handling from pagefault_mr
RDMA/mlx5: Set the HW IOVA of the child MRs to their place in the tree
RDMA/mlx5: Lift implicit_mr_alloc() into the two routines that call it
RDMA/mlx5: Rework implicit_mr_get_data
RDMA/mlx5: Delete struct mlx5_priv->mkey_table
RDMA/mlx5: Use a dedicated mkey xarray for ODP
RDMA/mlx5: Split sig_err MR data into its own xarray
RDMA/mlx5: Use SRCU properly in ODP prefetch
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
For creation, as soon as the umem_odp is created the notifier can be
called, however the underlying MR may not have been setup yet. This would
cause problems if mlx5_ib_invalidate_range() runs. There is some
confusing/ulocked/racy code that might by trying to solve this, but
without locks it isn't going to work right.
Instead trivially solve the problem by short-circuiting the invalidation
if there are not yet any DMA mapped pages. By definition there is nothing
to invalidate in this case.
The create code will have the umem fully setup before anything is DMA
mapped, and npages is fully locked by the umem_mutex.
For destroy, invalidate the entire MR at the HW to stop DMA then DMA unmap
the pages before destroying the MR. This drives npages to zero and
prevents similar racing with invalidate while the MR is undergoing
destruction.
Arguably it would be better if the umem was created after the MR and
destroyed before, but that would require a big rework of the MR code.
Fixes: 6aec21f6a832 ("IB/mlx5: Page faults handling infrastructure")
Link: https://lore.kernel.org/r/20191009160934.3143-15-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
These mkeys are entirely internal and are never used by the HW for
page fault. They should also never be used by userspace for prefetch.
Simplify & optimize things by not including them in the xarray.
Since the prefetch path can now never see a child mkey there is no need
for the second synchronize_srcu() during imr destroy.
Link: https://lore.kernel.org/r/20191009160934.3143-14-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Use SRCU in a sensible way by removing all MRs in the implicit tree from
the two xarrays (the update operation), then a synchronize, followed by a
normal single threaded teardown.
This is only a little unusual from the normal pattern as there can still
be some work pending in the unbound wq that may also require a workqueue
flush. This is tracked with a single atomic, consolidating the redundant
existing atomics and wait queue.
For understand-ability the entire ODP implicit create/destroy flow now
largely exists in a single pair of functions within odp.c, with a few
support functions for tearing down an unused child.
Link: https://lore.kernel.org/r/20191009160934.3143-13-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Now that the locking is simplified combine pagefault_implicit_mr() with
implicit_mr_get_data() so that we sweep over the idx range only once,
and do the single xlt update at the end, after the child umems are
setup.
This avoids double iteration/xa_loads plus the sketchy failure path if the
xa_load() fails.
Link: https://lore.kernel.org/r/20191009160934.3143-12-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Now that the child MRs are stored in an xarray we can rely on the SRCU
lock to protect the xa_load and use xa_cmpxchg on the slow allocation path
to resolve races with concurrent page fault.
This reduces the scope of the critical section of umem_mutex for implicit
MRs to only cover mlx5_ib_update_xlt, and avoids taking a lock at all if
the child MR is already in the xarray. This makes it consistent with the
normal ODP MR critical section for umem_lock, and the locking approach
used for destroying an unusued implicit child MR.
The MLX5_IB_UPD_XLT_ATOMIC is no longer needed in implicit_get_child_mr()
since it is no longer called with any locks.
Link: https://lore.kernel.org/r/20191009160934.3143-11-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Currently the child leaves are stored in the shared interval tree and
every lookup for a child must be done under the interval tree rwsem.
This is further complicated by dropping the rwsem during iteration (ie the
odp_lookup(), odp_next() pattern), which requires a very tricky an
difficult to understand locking scheme with SRCU.
Instead reserve the interval tree for the exclusive use of the mmu
notifier related code in umem_odp.c and give each implicit MR a xarray
containing all the child MRs.
Since the size of each child is 1GB of VA, a 1 level xarray will index 64G
of VA, and a 2 level will index 2TB, making xarray a much better
data structure choice than an interval tree.
The locking properties of xarray will be used in the next patches to
rework the implicit ODP locking scheme into something simpler.
At this point, the xarray is locked by the implicit MR's umem_mutex, and
read can also be locked by the odp_srcu.
Link: https://lore.kernel.org/r/20191009160934.3143-10-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The single routine has a very confusing scheme to advance to the next
child MR when working on an implicit parent. This scheme can only be used
when working with an implicit parent and must not be triggered when
working on a normal MR.
Re-arrange things by directly putting all the single-MR stuff into one
function and calling it in a loop for the implicit case. Simplify some of
the error handling in the new pagefault_real_mr() to remove unneeded gotos.
Link: https://lore.kernel.org/r/20191009160934.3143-9-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Instead of rewriting all the IOVA's to 0 as things progress down the tree
make the IOVA of the children equal to placement in the tree. This makes
things easier to understand by keeping mmkey.iova == HW configuration.
Link: https://lore.kernel.org/r/20191009160934.3143-8-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This makes the routines easier to understand, particularly with respect
the locking requirements of the entire sequence. The implicit_mr_alloc()
had a lot of ifs specializing it to each of the callers, and only a very
small amount of code was actually shared.
Following patches will cause the flow in the two functions to diverge
further.
Link: https://lore.kernel.org/r/20191009160934.3143-7-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This function is intended to loop across each MTT chunk in the implicit
parent that intersects the range [io_virt, io_virt+bnct). But it is has a
confusing construction, so:
- Consistently use imr and odp_imr to refer to the implicit parent
to avoid confusion with the normal mr and odp of the child
- Directly compute the inclusive start/end indexes by shifting. This is
clearer to understand the intent and avoids any errors from unaligned
values of addr
- Iterate directly over the range of MTT indexes, do not make a loop
out of goto
- Follow 'success oriented flow', with goto error unwind
- Directly calculate the range of idx's that need update_xlt
- Ensure that any leaf MR added to the interval tree always results in an
update to the XLT
Link: https://lore.kernel.org/r/20191009160934.3143-6-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
There is a per device xarray storing mkeys that is used to store every
mkey in the system. However, this xarray is now only read by ODP for
certain ODP designated MRs (ODP, implicit ODP, MW, DEVX_INDIRECT).
Create an xarray only for use by ODP, that only contains ODP related
MKeys. This xarray is protected by SRCU and all erases are protected by a
synchronize.
This improves performance:
- All MRs in the odp_mkeys xarray are ODP MRs, so some tests for is_odp()
can be deleted. The xarray will also consume fewer nodes.
- normal MR's are never mixed with ODP MRs in a SRCU data structure so
performance sucking synchronize_srcu() on every MR destruction is not
needed.
- No smp_load_acquire(live) and xa_load() double barrier on read
Due to the SRCU locking scheme care must be taken with the placement of
the xa_store(). Once it completes the MR is immediately visible to other
threads and only through a xa_erase() & synchronize_srcu() cycle could it
be destroyed.
Link: https://lore.kernel.org/r/20191009160934.3143-4-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
When working with SRCU protected xarrays the xarray itself should be the
SRCU 'update' point. Instead prefetch is using live as the SRCU update
point and this prevents switching the locking design to use the xarray
instead.
To solve this the prefetch must only read from the xarray once, and hold
on to the actual MR pointer for the duration of the async
operation. Incrementing num_pending_prefetch delays destruction of the MR,
so it is suitable.
Prefetch calls directly to the pagefault_mr using the MR pointer and only
does a single xarray lookup.
All the testing if a MR is prefetchable or not is now done only in the
prefetch code and removed from the pagefault critical path.
Link: https://lore.kernel.org/r/20191009160934.3143-2-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-----BEGIN PGP SIGNATURE-----
iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl210Z8eHHRvcnZhbGRz
QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGv+kIAKRpO7EuDokQL4qp
hxEEaCMJA1T055EMlNU6FVAq/ZbmapzreUyNYiRMpPWKGTWNMkhIcZQfysYeGZz5
y/KRxAiVxlcB+3v3yRmoZd/XoQmhgvJmqD4zhaGI2Utonow4f/SGSEFFZqqs9WND
4HJROjZHgQ4JBxg9Z+QMo0FxbV/DCZpEOUq51N9WJywyyDRb18zotE83stpU+pE2
fjqT7mk0NLrnYXuDRAbFC1Aau9ed4H6LlwLmxaqxq/Pt5Rz7wIKwKL9HIT4Dm/0a
qpani6phhHWL7MwUpa2wkEonFCD03rJFl3DUVJo64Ijh4up5D/jyXQ+GKV2P4WKJ
275Rb5Q=
=WiZZ
-----END PGP SIGNATURE-----
Merge tag 'v5.4-rc5' into rdma.git for-next
Linux 5.4-rc5
For dependencies in the next patches
Conflict resolved by keeping the delete of the unlock.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Provide an ODP explicit/implicit type as part of 'rdma -dd resource show
mr' dump.
For example:
$ rdma -dd resource show mr
dev mlx5_0 mrn 1 rkey 0xa99a lkey 0xa99a mrlen 50000000
pdn 9 pid 7372 comm ibv_rc_pingpong drv_odp explicit
For non-ODP MRs, we won't print "drv_odp ..." at all.
Link: https://lore.kernel.org/r/20191016062308.11886-4-leon@kernel.org
Signed-off-by: Erez Alfasi <ereza@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Introduce ODP diagnostic counters and count the following
per MR within IB/mlx5 driver:
1) Page faults:
Total number of faulted pages.
2) Page invalidations:
Total number of pages invalidated by the OS during all
invalidation events. The translations can be no longer
valid due to either non-present pages or mapping changes.
Link: https://lore.kernel.org/r/20191016062308.11886-2-leon@kernel.org
Signed-off-by: Erez Alfasi <ereza@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
live is used to signal to the pagefault thread that the MR is initialized
and ready for use. It should be after the umem is assigned and all other
setup is completed. This prevents races (at least) of the form:
CPU0 CPU1
mlx5_ib_alloc_implicit_mr()
implicit_mr_alloc()
live = 1
imr->umem = umem
num_pending_prefetch_inc()
if (live)
atomic_inc(num_pending_prefetch)
atomic_set(num_pending_prefetch,0) // Overwrites other thread's store
Further, live is being used with SRCU as the 'update' in an
acquire/release fashion, so it can not be read and written raw.
Move all live = 1's to after MR initialization is completed and use
smp_store_release/smp_load_acquire() for manipulating it.
Add a missing live = 0 when an implicit MR child is deleted, before
queuing work to do synchronize_srcu().
The barriers in update_odp_mr() were some broken attempt to create a
acquire/release, but were not even applied consistently and missed the
point, delete it as well.
Fixes: 6aec21f6a832 ("IB/mlx5: Page faults handling infrastructure")
Link: https://lore.kernel.org/r/20191001153821.23621-6-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This fixes a race of the form:
CPU0 CPU1
mlx5_ib_invalidate_range() mlx5_ib_invalidate_range()
// This one actually makes npages == 0
ib_umem_odp_unmap_dma_pages()
if (npages == 0 && !dying)
// This one does nothing
ib_umem_odp_unmap_dma_pages()
if (npages == 0 && !dying)
dying = 1;
dying = 1;
schedule_work(&umem_odp->work);
// Double schedule of the same work
schedule_work(&umem_odp->work); // BOOM
npages and dying must be read and written under the umem_mutex lock.
Since whenever ib_umem_odp_unmap_dma_pages() is called mlx5 must also call
mlx5_ib_update_xlt, and both need to be done in the same locking region,
hoist the lock out of unmap.
This avoids an expensive double critical section in
mlx5_ib_invalidate_range().
Fixes: 81713d3788d2 ("IB/mlx5: Add implicit MR support")
Link: https://lore.kernel.org/r/20191001153821.23621-4-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
mlx5_ib_update_xlt() must be protected against parallel free of the MR it
is accessing, also it must be called single threaded while updating the
HW. Otherwise we can have races of the form:
CPU0 CPU1
mlx5_ib_update_xlt()
mlx5_odp_populate_klm()
odp_lookup() == NULL
pklm = ZAP
implicit_mr_get_data()
implicit_mr_alloc()
<update interval tree>
mlx5_ib_update_xlt
mlx5_odp_populate_klm()
odp_lookup() != NULL
pklm = VALID
mlx5_ib_post_send_wait()
mlx5_ib_post_send_wait() // Replaces VALID with ZAP
This can be solved by putting both the SRCU and the umem_mutex lock around
every call to mlx5_ib_update_xlt(). This ensures that the content of the
interval tree relavent to mlx5_odp_populate_klm() (ie mr->parent == mr)
will not change while it is running, and thus the posted WRs to update the
KLM will always reflect the correct information.
The race above will resolve by either having CPU1 wait till CPU0 completes
the ZAP or CPU0 will run after the add and instead store VALID.
The pagefault path adding children already holds the umem_mutex and SRCU,
so the only missed lock is during MR destruction.
Fixes: 81713d3788d2 ("IB/mlx5: Add implicit MR support")
Link: https://lore.kernel.org/r/20191001153821.23621-3-jgg@ziepe.ca
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
There is no reason to call return at the end of function which returns
void. Remove this unnecessary statement.
Link: https://lore.kernel.org/r/20191002122517.17721-3-leon@kernel.org
Signed-off-by: Erez Alfasi <ereza@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The removal of 'buffer' in the patch below caused free_page() to use a
value that had been offset since the wqe pointer is adjusted while the
routine runs.
The current implementation of free_pages() rounds down to a pfn,
discarding the adjustment, but this is not the right way to use the
API. Preserve the initial value and use it for free_page().
Fixes: 0f51427bd097 ("RDMA/mlx5: Cleanup WQE page fault handler")
Link: https://lore.kernel.org/r/20190916064818.19823-2-leon@kernel.org
Signed-off-by: Danit Goldberg <danitg@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
To resolve dependencies in following patches
mlx5_ib.h conflict resolved by keeing both hunks
Linux 5.3-rc8
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Michael Guralnik says:
====================
The series adds support for on-demand paging for DC transport.
As DC is a mlx-only transport, the capabilities are exposed to the user
using DEVX objects and later on through mlx5dv_query_device.
====================
Based on the mlx5-next branch from
git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux for
dependencies
* branch 'mlx5-odp-dc':
IB/mlx5: Add page fault handler for DC initiator WQE
IB/mlx5: Remove check of FW capabilities in ODP page fault handling
net/mlx5: Set ODP capabilities for DC transport to max
Parsing DC initiator WQEs upon page fault requires skipping an address
vector segment, as in UD WQEs.
Link: https://lore.kernel.org/r/20190819120815.21225-4-leon@kernel.org
Signed-off-by: Michael Guralnik <michaelgur@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
As page fault handling is initiated by FW, there is no need to check that
the ODP supports the operation and transport.
Link: https://lore.kernel.org/r/20190819120815.21225-3-leon@kernel.org
Signed-off-by: Michael Guralnik <michaelgur@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
