These are rare, but can be helpful at tracking down DMAR and other
problems.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Name them "trace_xprtrdma_op_*" so they can be easily enabled as a
group. No trace point is added where the generic layer already has
observability.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The mr_map trace points were capturing information about the previous
use of the MR rather than about the segment that was just mapped.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The chunk-related trace points capture nearly the same information
as the MR-related trace points.
Also, rename them so globbing can be used to enable or disable
these trace points more easily.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up. The last use of these fields was in commit 173b8f49b3
("xprtrdma: Demote "connect" log messages") .
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Remove dprintk() call sites that report rare or impossible
errors. Leave a few that display high-value low noise status
information.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: There's little chance of contention between the use of
rb_lock and rb_reqslock, so merge the two. This avoids having to
take both in some (possibly future) cases.
Transport tear-down is already serialized, thus there is no need for
locking at all when destroying rpcrdma_reqs.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
For better observability of parsing errors, return the error code
generated in the decoders to the upper layer consumer.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Since commit ffe1f0df58 ("rpcrdma: Merge svcrdma and xprtrdma
modules into one"), the forward and backchannel components are part
of the same kernel module. A separate request_module() call in the
backchannel code is no longer necessary.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Commit 431f6eb357 ("SUNRPC: Add a label for RPC calls that require
allocation on receive") didn't update similar logic in rpc_rdma.c.
I don't think this is a bug, per-se; the commit just adds more
careful checking for broken upper layer behavior.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Place the associated RPC transaction's XID in the upper 32 bits of
each RDMA segment's rdma_offset field. There are two reasons to do
this:
- The R_key only has 8 bits that are different from registration to
registration. The XID adds more uniqueness to each RDMA segment to
reduce the likelihood of a software bug on the server reading from
or writing into memory it's not supposed to.
- On-the-wire RDMA Read and Write requests do not otherwise carry
any identifier that matches them up to an RPC. The XID in the
upper 32 bits will act as an eye-catcher in network captures.
Suggested-by: Tom Talpey <ttalpey@microsoft.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Now that there is only FRWR, there is no need for a memory
registration switch. The indirect calls to the memreg operations can
be replaced with faster direct calls.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
FMR is not supported on most recent RDMA devices. It is also less
secure than FRWR because an FMR memory registration can expose
adjacent bytes to remote reading or writing. As discussed during the
RDMA BoF at LPC 2018, it is time to remove support for FMR in the
NFS/RDMA client stack.
Note that NFS/RDMA server-side uses either local memory registration
or FRWR. FMR is not used.
There are a few Infiniband/RoCE devices in the kernel tree that do
not appear to support MEM_MGT_EXTENSIONS (FRWR), and therefore will
not support client-side NFS/RDMA after this patch. These are:
- mthca
- qib
- hns (RoCE)
Users of these devices can use NFS/TCP on IPoIB instead.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Some devices advertise a large max_fast_reg_page_list_len
capability, but perform optimally when MRs are significantly smaller
than that depth -- probably when the MR itself is no larger than a
page.
By default, the RDMA R/W core API uses max_sge_rd as the maximum
page depth for MRs. For some devices, the value of max_sge_rd is
1, which is also not optimal. Thus, when max_sge_rd is larger than
1, use that value. Otherwise use the value of the
max_fast_reg_page_list_len attribute.
I've tested this with CX-3 Pro, FastLinq, and CX-5 devices. It
reproducibly improves the throughput of large I/Os by several
percent.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
With certain combinations of krb5i/p, MR size, and r/wsize, I/O can
fail with EMSGSIZE. This is because the calculated value of
ri_max_segs (the max number of MRs per RPC) exceeded
RPCRDMA_MAX_HDR_SEGS, which caused Read or Write list encoding to
walk off the end of the transport header.
Once that was addressed, the ro_maxpages result has to be corrected
to account for the number of MRs needed for Reply chunks, which is
2 MRs smaller than a normal Read or Write chunk.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Transport disconnect processing does a "wake pending tasks" at
various points.
Suppose an RPC Reply is being processed. The RPC task that Reply
goes with is waiting on the pending queue. If a disconnect wake-up
happens before reply processing is done, that reply, even if it is
good, is thrown away, and the RPC has to be sent again.
This window apparently does not exist for socket transports because
there is a lock held while a reply is being received which prevents
the wake-up call until after reply processing is done.
To resolve this, all RPC replies being processed on an RPC-over-RDMA
transport have to complete before pending tasks are awoken due to a
transport disconnect.
Callers that already hold the transport write lock may invoke
->ops->close directly. Others use a generic helper that schedules
a close when the write lock can be taken safely.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
After thinking about this more, and auditing other kernel ULP imple-
mentations, I believe that a DISCONNECT cm_event will occur after a
fatal QP event. If that's the case, there's no need for an explicit
disconnect in the QP event handler.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
To address a connection-close ordering problem, we need the ability
to drain the RPC completions running on rpcrdma_receive_wq for just
one transport. Give each transport its own RPC completion workqueue,
and drain that workqueue when disconnecting the transport.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Divide the work cleanly:
- rpcrdma_wc_receive is responsible only for RDMA Receives
- rpcrdma_reply_handler is responsible only for RPC Replies
- the posted send and receive counts both belong in rpcrdma_ep
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The recovery case in frwr_op_unmap_sync needs to DMA unmap each MR.
frwr_release_mr does not DMA-unmap, but the recycle worker does.
Fixes: 61da886bf7 ("xprtrdma: Explicitly resetting MRs is ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
While chasing yet another set of DMAR fault reports, I noticed that
the frwr recycler conflates whether or not an MR has been DMA
unmapped with frwr->fr_state. Actually the two have only an indirect
relationship. It's in fact impossible to guess reliably whether the
MR has been DMA unmapped based on its fr_state field, especially as
the surrounding code and its assumptions have changed over time.
A better approach is to track the DMA mapping status explicitly so
that the recycler is less brittle to unexpected situations, and
attempts to DMA-unmap a second time are prevented.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org # v4.20
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
xpo_prep_reply_hdr are not used now.
It was defined for tcp transport only, however it cannot be
called indirectly, so let's move it to its caller and
remove unused callback.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Remove svc_xprt_class svc_rdma_bc_class and related functions.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
svc_serv-> sv_bc_xprt is netns-unsafe and cannot be used as pointer.
To prevent its misuse in future it is replaced by new boolean flag.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Make all the required change to start use the ib_device_ops structure.
Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
o Select the R_key to invalidate while the CPU cache still contains
the received RPC Call transport header, rather than waiting until
we're about to send the RPC Reply.
o Choose Send With Invalidate if there is exactly one distinct R_key
in the received transport header. If there's more than one, the
client will have to perform local invalidation after it has
already waited for remote invalidation.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
already supported COPY, by copying a limited amount of data and then
returning a short result, letting the client resend. The asynchronous
protocol should offer better performance at the expense of some
complexity.
The other highlight is Trond's work to convert the duplicate reply cache
to a red-black tree, and to move it and some other server caches to RCU.
(Previously these have meant taking global spinlocks on every RPC.)
Otherwise, some RDMA work and miscellaneous bugfixes.
-----BEGIN PGP SIGNATURE-----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=TTo0
-----END PGP SIGNATURE-----
Merge tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"Olga added support for the NFSv4.2 asynchronous copy protocol. We
already supported COPY, by copying a limited amount of data and then
returning a short result, letting the client resend. The asynchronous
protocol should offer better performance at the expense of some
complexity.
The other highlight is Trond's work to convert the duplicate reply
cache to a red-black tree, and to move it and some other server caches
to RCU. (Previously these have meant taking global spinlocks on every
RPC)
Otherwise, some RDMA work and miscellaneous bugfixes"
* tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linux: (30 commits)
lockd: fix access beyond unterminated strings in prints
nfsd: Fix an Oops in free_session()
nfsd: correctly decrement odstate refcount in error path
svcrdma: Increase the default connection credit limit
svcrdma: Remove try_module_get from backchannel
svcrdma: Remove ->release_rqst call in bc reply handler
svcrdma: Reduce max_send_sges
nfsd: fix fall-through annotations
knfsd: Improve lookup performance in the duplicate reply cache using an rbtree
knfsd: Further simplify the cache lookup
knfsd: Simplify NFS duplicate replay cache
knfsd: Remove dead code from nfsd_cache_lookup
SUNRPC: Simplify TCP receive code
SUNRPC: Replace the cache_detail->hash_lock with a regular spinlock
SUNRPC: Remove non-RCU protected lookup
NFS: Fix up a typo in nfs_dns_ent_put
NFS: Lockless DNS lookups
knfsd: Lockless lookup of NFSv4 identities.
SUNRPC: Lockless server RPCSEC_GSS context lookup
knfsd: Allow lockless lookups of the exports
...
Since commit ffe1f0df58 ("rpcrdma: Merge svcrdma and xprtrdma
modules into one"), the forward and backchannel components are part
of the same kernel module. A separate try_module_get() call in the
backchannel code is no longer necessary.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Similar to a change made in the client's forward channel reply
handler: The xprt_release_rqst_cong() call is not necessary.
Also, release xprt->recv_lock when taking xprt->transport_lock
to avoid disabling and enabling BH's while holding another
spin lock.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There's no need to request a large number of send SGEs because the
inline threshold already constrains the number of SGEs per Send.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Stable bugfixes:
- Reset credit grant properly after a disconnect
Other bugfixes and cleanups:
- xprt_release_rqst_cong is called outside of transport_lock
- Create more MRs at a time and toss out old ones during recovery
- Various improvements to the RDMA connection and disconnection code:
- Improve naming of trace events, functions, and variables
- Add documenting comments
- Fix metrics and stats reporting
- Fix a tracepoint sparse warning
-----BEGIN PGP SIGNATURE-----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=SxSD
-----END PGP SIGNATURE-----
Merge tag 'nfs-rdma-for-4.20-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
NFS RDMA client updates for Linux 4.20
Stable bugfixes:
- Reset credit grant properly after a disconnect
Other bugfixes and cleanups:
- xprt_release_rqst_cong is called outside of transport_lock
- Create more MRs at a time and toss out old ones during recovery
- Various improvements to the RDMA connection and disconnection code:
- Improve naming of trace events, functions, and variables
- Add documenting comments
- Fix metrics and stats reporting
- Fix a tracepoint sparse warning
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Clean up: Use the appropriate C macro instead of open-coding
container_of() .
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: fill in or update documenting comments for transport
switch entry points.
For xprt_rdma_allocate:
The first paragraph is no longer true since commit 5a6d1db455
("SUNRPC: Add a transport-specific private field in rpc_rqst").
The second paragraph is no longer true since commit 54cbd6b0c6
("xprtrdma: Delay DMA mapping Send and Receive buffers").
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
To show that a caller did attempt to allocate and post more Receive
buffers, the trace point in rpcrdma_post_recvs() should report when
rpcrdma_post_recvs() was invoked but no new Receive buffers were
posted.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: rb_flags might be used for other things besides
RPCRDMA_BUF_F_EMPTY_SCQ, so initialize it in a generic spot
instead of in a send-completion-queue-related helper.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: This code was copied from xprtsock.c and
backchannel_rqst.c. For rpcrdma, the backchannel server runs
exclusively in process context, thus disabling bottom-halves is
unnecessary.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Replace the hashed memory address of the target rpcrdma_ep
with the server's IP address and port. The server address is more
useful in an administrative error message.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Use a function name that is consistent with the RDMA core
API and with other consumers. Because this is a function that is
invoked from outside the rpcrdma.ko module, add an appropriate
documenting comment.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Currently, when a connection is established, rpcrdma_conn_upcall
invokes rpcrdma_conn_func and then
wake_up_all(&ep->rep_connect_wait). The former wakes waiting RPCs,
but the connect worker is not done yet, and that leads to races,
double wakes, and difficulty understanding how this logic is
supposed to work.
Instead, collect all the "connection established" logic in the
connect worker (xprt_rdma_connect_worker). A disconnect worker is
retained to handle provider upcalls safely.
Fixes: 254f91e2fa ("xprtrdma: RPC/RDMA must invoke ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Eliminate the FALLTHROUGH into the default arm to make the
switch easier to understand.
Also, as long as I'm here, do not display the memory address of the
target rpcrdma_ep. A hashed memory address is of marginal use here.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up.
Since commit 173b8f49b3 ("xprtrdma: Demote "connect" log messages")
there has been no need to initialize connstat to zero. In fact, in
this code path there's now no reason not to set rep_connected
directly.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: The convention throughout other parts of xprtrdma is to
name variables of type struct rpcrdma_xprt "r_xprt", not "xprt".
This convention enables the use of the name "xprt" for a "struct
rpc_xprt" type variable, as in other parts of the RPC client.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Use a function name that is consistent with the RDMA core
API and with other consumers. Because this is a function that is
invoked from outside the rpcrdma.ko module, add an appropriate
documenting comment.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The way connection-oriented transports report connect_time is wrong:
it's supposed to be in seconds, not in jiffies.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
For TCP, the logic in xprt_connect_status is currently never invoked
to record a successful connection. Commit 2a4919919a ("SUNRPC:
Return EAGAIN instead of ENOTCONN when waking up xprt->pending")
changed the way TCP xprt's are awoken after a connect succeeds.
Instead, change connection-oriented transports to bump connect_count
and compute connect_time the moment that XPRT_CONNECTED is set.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up the names of trace events related to MRs so that it's
easy to enable these with a glob.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When a memory operation fails, the MR's driver state might not match
its hardware state. The only reliable recourse is to dereg the MR.
This is done in ->ro_recover_mr, which then attempts to allocate a
fresh MR to replace the released MR.
Since commit e2ac236c0b ("xprtrdma: Allocate MRs on demand"),
xprtrdma dynamically allocates MRs. It can add more MRs whenever
they are needed.
That makes it possible to simply release an MR when a memory
operation fails, instead of "recovering" it. It will automatically
be replaced by the on-demand MR allocator.
This commit is a little larger than I wanted, but it replaces
->ro_recover_mr, rb_recovery_lock, rb_recovery_worker, and the
rb_stale_mrs list with a generic work queue.
Since MRs are no longer orphaned, the mrs_orphaned metric is no
longer used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Some devices require more than 3 MRs to build a single 1MB I/O.
Ensure that rpcrdma_mrs_create() will add enough MRs to build that
I/O.
In a subsequent patch I'm changing the MR recovery logic to just
toss out the MRs. In that case it's possible for ->send_request to
loop acquiring some MRs, not getting enough, getting called again,
recycling the previous MRs, then not getting enough, lather rinse
repeat. Thus first we need to ensure enough MRs are created to
prevent that loop.
I'm "reusing" ia->ri_max_segs. All of its accessors seem to want the
maximum number of data segments plus two, so I'm going to bake that
into the initial calculation.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
On a fresh connection, an RPC/RDMA client is supposed to send only
one RPC Call until it gets a credit grant in the first RPC Reply
from the server [RFC 8166, Section 3.3.3].
There is a bug in the Linux client's credit accounting mechanism
introduced by commit e7ce710a88 ("xprtrdma: Avoid deadlock when
credit window is reset"). On connect, it simply dumps all pending
RPC Calls onto the new connection.
Servers have been tolerant of this bad behavior. Currently no server
implementation ever changes its credit grant over reconnects, and
servers always repost enough Receives before connections are fully
established.
To correct this issue, ensure that the client resets both the credit
grant _and_ the congestion window when handling a reconnect.
Fixes: e7ce710a88 ("xprtrdma: Avoid deadlock when credit ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Since commit ce7c252a8c ("SUNRPC: Add a separate spinlock to
protect the RPC request receive list") the RPC/RDMA reply handler
has been calling xprt_release_rqst_cong without holding
xprt->transport_lock.
I think the only way this call is ever made is if the credit grant
increases and there are RPCs pending. Current server implementations
do not change their credit grant during operation (except at
connect time).
Commit e7ce710a88 ("xprtrdma: Avoid deadlock when credit window is
reset") added the ->release_rqst call because UDP invokes
xprt_adjust_cwnd(), which calls __xprt_put_cong() after adjusting
xprt->cwnd. Both xprt_release() and ->xprt_release_xprt already wake
another task in this case, so it is safe to remove this call from
the reply handler.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Treat socket write space handling in the same way we now treat transport
congestion: by denying the XPRT_LOCK until the transport signals that it
has free buffer space.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Both RDMA and UDP transports require the request to get a "congestion control"
credit before they can be transmitted. Right now, this is done when
the request locks the socket. We'd like it to happen when a request attempts
to be transmitted for the first time.
In order to support retransmission of requests that already hold such
credits, we also want to ensure that they get queued first, so that we
don't deadlock with requests that have yet to obtain a credit.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When we shift to using the transmit queue, then the task that holds the
write lock will not necessarily be the same as the one being transmitted.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Separate out the action of adding a request to the reply queue so that the
backchannel code can simply skip calling it altogether.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Stable bufixes:
- v3.17+: Fix an off-by-one in bl_map_stripe()
- v4.9+: NFSv4 client live hangs after live data migration recovery
- v4.18+: xprtrdma: Fix disconnect regression
- v4.14+: Fix locking in pnfs_generic_recover_commit_reqs
- v4.9+: Fix a sleep in atomic context in nfs4_callback_sequence()
Features:
- Add support for asynchronous server-side COPY operations
Other bugfixes and cleanups:
- Optitmizations and fixes involving NFS v4.1 / pNFS layout handling
- Optimize lseek(fd, SEEK_CUR, 0) on directories to avoid locking
- Immediately reschedule writeback when the server replies with an error
- Fix excessive attribute revalidation in nfs_execute_ok()
- Add error checking to nfs_idmap_prepare_message()
- Use new vm_fault_t return type
- Return a delegation when reclaiming one that the server has recalled
- Referrals should inherit proto setting from parents
- Make rpc_auth_create_args a const
- Improvements to rpc_iostats tracking
- Fix a potential reference leak when there is an error processing a callback
- Fix rmdir / mkdir / rename nlink accounting
- Fix updating inode change attribute
- Fix error handling in nfsn4_sp4_select_mode()
- Use an appropriate work queue for direct-write completion
- Don't busy wait if NFSv4 session draining is interrupted
-----BEGIN PGP SIGNATURE-----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=8+9t
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-4.19-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client updates from Anna Schumaker:
"These patches include adding async support for the v4.2 COPY
operation. I think Bruce is planning to send the server patches for
the next release, but I figured we could get the client side out of
the way now since it's been in my tree for a while. This shouldn't
cause any problems, since the server will still respond with
synchronous copies even if the client requests async.
Features:
- Add support for asynchronous server-side COPY operations
Stable bufixes:
- Fix an off-by-one in bl_map_stripe() (v3.17+)
- NFSv4 client live hangs after live data migration recovery (v4.9+)
- xprtrdma: Fix disconnect regression (v4.18+)
- Fix locking in pnfs_generic_recover_commit_reqs (v4.14+)
- Fix a sleep in atomic context in nfs4_callback_sequence() (v4.9+)
Other bugfixes and cleanups:
- Optimizations and fixes involving NFS v4.1 / pNFS layout handling
- Optimize lseek(fd, SEEK_CUR, 0) on directories to avoid locking
- Immediately reschedule writeback when the server replies with an
error
- Fix excessive attribute revalidation in nfs_execute_ok()
- Add error checking to nfs_idmap_prepare_message()
- Use new vm_fault_t return type
- Return a delegation when reclaiming one that the server has
recalled
- Referrals should inherit proto setting from parents
- Make rpc_auth_create_args a const
- Improvements to rpc_iostats tracking
- Fix a potential reference leak when there is an error processing a
callback
- Fix rmdir / mkdir / rename nlink accounting
- Fix updating inode change attribute
- Fix error handling in nfsn4_sp4_select_mode()
- Use an appropriate work queue for direct-write completion
- Don't busy wait if NFSv4 session draining is interrupted"
* tag 'nfs-for-4.19-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (54 commits)
pNFS: Remove unwanted optimisation of layoutget
pNFS/flexfiles: ff_layout_pg_init_read should exit on error
pNFS: Treat RECALLCONFLICT like DELAY...
pNFS: When updating the stateid in layoutreturn, also update the recall range
NFSv4: Fix a sleep in atomic context in nfs4_callback_sequence()
NFSv4: Fix locking in pnfs_generic_recover_commit_reqs
NFSv4: Fix a typo in nfs4_init_channel_attrs()
NFSv4: Don't busy wait if NFSv4 session draining is interrupted
NFS recover from destination server reboot for copies
NFS add a simple sync nfs4_proc_commit after async COPY
NFS handle COPY ERR_OFFLOAD_NO_REQS
NFS send OFFLOAD_CANCEL when COPY killed
NFS export nfs4_async_handle_error
NFS handle COPY reply CB_OFFLOAD call race
NFS add support for asynchronous COPY
NFS COPY xdr handle async reply
NFS OFFLOAD_CANCEL xdr
NFS CB_OFFLOAD xdr
NFS: Use an appropriate work queue for direct-write completion
NFSv4: Fix error handling in nfs4_sp4_select_mode()
...
missing Chuck's fixes for the problem with callbacks over GSS from
multi-homed servers, and a smaller fix from Laura Abbott.
-----BEGIN PGP SIGNATURE-----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=JnLK
-----END PGP SIGNATURE-----
Merge tag 'nfsd-4.19-1' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"Chuck Lever fixed a problem with NFSv4.0 callbacks over GSS from
multi-homed servers.
The only new feature is a minor bit of protocol (change_attr_type)
which the client doesn't even use yet.
Other than that, various bugfixes and cleanup"
* tag 'nfsd-4.19-1' of git://linux-nfs.org/~bfields/linux: (27 commits)
sunrpc: Add comment defining gssd upcall API keywords
nfsd: Remove callback_cred
nfsd: Use correct credential for NFSv4.0 callback with GSS
sunrpc: Extract target name into svc_cred
sunrpc: Enable the kernel to specify the hostname part of service principals
sunrpc: Don't use stack buffer with scatterlist
rpc: remove unneeded variable 'ret' in rdma_listen_handler
nfsd: use true and false for boolean values
nfsd: constify write_op[]
fs/nfsd: Delete invalid assignment statements in nfsd4_decode_exchange_id
NFSD: Handle full-length symlinks
NFSD: Refactor the generic write vector fill helper
svcrdma: Clean up Read chunk path
svcrdma: Avoid releasing a page in svc_xprt_release()
nfsd: Mark expected switch fall-through
sunrpc: remove redundant variables 'checksumlen','blocksize' and 'data'
nfsd: fix leaked file lock with nfs exported overlayfs
nfsd: don't advertise a SCSI layout for an unsupported request_queue
nfsd: fix corrupted reply to badly ordered compound
nfsd: clarify check_op_ordering
...
The ret is not modified after initalization, So just remove the variable
and return 0.
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Simplify the error handling at the tail of recv_read_chunk() by
re-arranging rq_pages[] housekeeping and documenting it properly.
NB: In this path, svc_rdma_recvfrom returns zero. Therefore no
subsequent reply processing is done on the svc_rqstp, and thus the
rq_respages field does not need to be updated.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
svc_xprt_release() invokes svc_free_res_pages(), which releases
pages between rq_respages and rq_next_page.
Historically, the RPC/RDMA transport has set these two pointers to
be different by one, which means:
- one page gets released when svc_recv returns 0. This normally
happens whenever one or more RDMA Reads need to be dispatched to
complete construction of an RPC Call.
- one page gets released after every call to svc_send.
In both cases, this released page is immediately refilled by
svc_alloc_arg. There does not seem to be a reason for releasing this
page.
To avoid this unnecessary memory allocator traffic, set rq_next_page
more carefully.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Variables 'checksumlen','blocksize' and 'data' are being assigned,
but are never used, hence they are redundant and can be removed.
Fix the following warning:
net/sunrpc/auth_gss/gss_krb5_wrap.c:443:7: warning: variable ‘blocksize’ set but not used [-Wunused-but-set-variable]
net/sunrpc/auth_gss/gss_krb5_crypto.c:376:15: warning: variable ‘checksumlen’ set but not used [-Wunused-but-set-variable]
net/sunrpc/xprtrdma/svc_rdma.c:97:9: warning: variable ‘data’ set but not used [-Wunused-but-set-variable]
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
I found that injecting disconnects with v4.18-rc resulted in
random failures of the multi-threaded git regression test.
The root cause appears to be that, after a reconnect, the
RPC/RDMA transport is waking pending RPCs before the transport has
posted enough Receive buffers to receive the Replies. If a Reply
arrives before enough Receive buffers are posted, the connection
is dropped. A few connection drops happen in quick succession as
the client and server struggle to regain credit synchronization.
This regression was introduced with commit 7c8d9e7c88 ("xprtrdma:
Move Receive posting to Receive handler"). The client is supposed to
post a single Receive when a connection is established because
it's not supposed to send more than one RPC Call before it gets
a fresh credit grant in the first RPC Reply [RFC 8166, Section
3.3.3].
Unfortunately there appears to be a longstanding bug in the Linux
client's credit accounting mechanism. On connect, it simply dumps
all pending RPC Calls onto the new connection. It's possible it has
done this ever since the RPC/RDMA transport was added to the kernel
ten years ago.
Servers have so far been tolerant of this bad behavior. Currently no
server implementation ever changes its credit grant over reconnects,
and servers always repost enough Receives before connections are
fully established.
The Linux client implementation used to post a Receive before each
of these Calls. This has covered up the flooding send behavior.
I could try to correct this old bug so that the client sends exactly
one RPC Call and waits for a Reply. Since we are so close to the
next merge window, I'm going to instead provide a simple patch to
post enough Receives before a reconnect completes (based on the
number of credits granted to the previous connection).
The spurious disconnects will be gone, but the client will still
send multiple RPC Calls immediately after a reconnect.
Addressing the latter problem will wait for a merge window because
a) I expect it to be a large change requiring lots of testing, and
b) obviously the Linux client has interoperated successfully since
day zero while still being broken.
Fixes: 7c8d9e7c88 ("xprtrdma: Move Receive posting to ... ")
Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Since neither ib_post_send() nor ib_post_recv() modify the data structure
their second argument points at, declare that argument const. This change
makes it necessary to declare the 'bad_wr' argument const too and also to
modify all ULPs that call ib_post_send(), ib_post_recv() or
ib_post_srq_recv(). This patch does not change any functionality but makes
it possible for the compiler to verify whether the
ib_post_(send|recv|srq_recv) really do not modify the posted work request.
To make this possible, only one cast had to be introduce that casts away
constness, namely in rpcrdma_post_recvs(). The only way I can think of to
avoid that cast is to introduce an additional loop in that function or to
change the data type of bad_wr from struct ib_recv_wr ** into int
(an index that refers to an element in the work request list). However,
both approaches would require even more extensive changes than this
patch.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The call in svc_rdma_post_chunk_ctxt() does actually use bad_wr.
Fixes: ed288d74a9 ("net/xprtrdma: Simplify ib_post_(send|recv|srq_recv)() calls")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Instead of declaring and passing a dummy 'bad_wr' pointer, pass NULL
as third argument to ib_post_(send|recv|srq_recv)().
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This patch replaces the ib_device_attr.max_sge with max_send_sge and
max_recv_sge. It allows ulps to take advantage of devices that have very
different send and recv sge depths. For example cxgb4 has a max_recv_sge
of 4, yet a max_send_sge of 16. Splitting out these attributes allows
much more efficient use of the SQ for cxgb4 with ulps that use the RDMA_RW
API. Consider a large RDMA WRITE that has 16 scattergather entries.
With max_sge of 4, the ulp would send 4 WRITE WRs, but with max_sge of
16, it can be done with 1 WRITE WR.
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Selvin Xavier <selvin.xavier@broadcom.com>
Acked-by: Shiraz Saleem <shiraz.saleem@intel.com>
Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Highlights include:
Stable fixes:
- Fix a 1-byte stack overflow in nfs_idmap_read_and_verify_message
- Fix a hang due to incorrect error returns in rpcrdma_convert_iovs()
- Revert an incorrect change to the NFSv4.1 callback channel
- Fix a bug in the NFSv4.1 sequence error handling
Features and optimisations:
- Support for piggybacking a LAYOUTGET operation to the OPEN compound
- RDMA performance enhancements to deal with transport congestion
- Add proper SPDX tags for NetApp-contributed RDMA source
- Do not request delegated file attributes (size+change) from the server
- Optimise away a GETATTR in the lookup revalidate code when doing NFSv4 OPEN
- Optimise away unnecessary lookups for rename targets
- Misc performance improvements when freeing NFSv4 delegations
Bugfixes and cleanups:
- Try to fail quickly if proto=rdma
- Clean up RDMA receive trace points
- Fix sillyrename to return the delegation when appropriate
- Misc attribute revalidation fixes
- Immediately clear the pNFS layout on a file when the server returns ESTALE
- Return NFS4ERR_DELAY when delegation/layout recalls fail due to igrab()
- Fix the client behaviour on NFS4ERR_SEQ_FALSE_RETRY
-----BEGIN PGP SIGNATURE-----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=YWSl
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-4.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Stable fixes:
- Fix a 1-byte stack overflow in nfs_idmap_read_and_verify_message
- Fix a hang due to incorrect error returns in rpcrdma_convert_iovs()
- Revert an incorrect change to the NFSv4.1 callback channel
- Fix a bug in the NFSv4.1 sequence error handling
Features and optimisations:
- Support for piggybacking a LAYOUTGET operation to the OPEN compound
- RDMA performance enhancements to deal with transport congestion
- Add proper SPDX tags for NetApp-contributed RDMA source
- Do not request delegated file attributes (size+change) from the
server
- Optimise away a GETATTR in the lookup revalidate code when doing
NFSv4 OPEN
- Optimise away unnecessary lookups for rename targets
- Misc performance improvements when freeing NFSv4 delegations
Bugfixes and cleanups:
- Try to fail quickly if proto=rdma
- Clean up RDMA receive trace points
- Fix sillyrename to return the delegation when appropriate
- Misc attribute revalidation fixes
- Immediately clear the pNFS layout on a file when the server returns
ESTALE
- Return NFS4ERR_DELAY when delegation/layout recalls fail due to
igrab()
- Fix the client behaviour on NFS4ERR_SEQ_FALSE_RETRY"
* tag 'nfs-for-4.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (80 commits)
skip LAYOUTRETURN if layout is invalid
NFSv4.1: Fix the client behaviour on NFS4ERR_SEQ_FALSE_RETRY
NFSv4: Fix a typo in nfs41_sequence_process
NFSv4: Revert commit 5f83d86cf5 ("NFSv4.x: Fix wraparound issues..")
NFSv4: Return NFS4ERR_DELAY when a layout recall fails due to igrab()
NFSv4: Return NFS4ERR_DELAY when a delegation recall fails due to igrab()
NFSv4.0: Remove transport protocol name from non-UCS client ID
NFSv4.0: Remove cl_ipaddr from non-UCS client ID
NFSv4: Fix a compiler warning when CONFIG_NFS_V4_1 is undefined
NFS: Filter cache invalidation when holding a delegation
NFS: Ignore NFS_INO_REVAL_FORCED in nfs_check_inode_attributes()
NFS: Improve caching while holding a delegation
NFS: Fix attribute revalidation
NFS: fix up nfs_setattr_update_inode
NFSv4: Ensure the inode is clean when we set a delegation
NFSv4: Ignore NFS_INO_REVAL_FORCED in nfs4_proc_access
NFSv4: Don't ask for delegated attributes when adding a hard link
NFSv4: Don't ask for delegated attributes when revalidating the inode
NFS: Pass the inode down to the getattr() callback
NFSv4: Don't request size+change attribute if they are delegated to us
...
from Chuck Lever with new trace points, miscellaneous cleanups, and
streamlining of the send and receive paths. Other than that, some
miscellaneous bugfixes.
-----BEGIN PGP SIGNATURE-----
iQIcBAABAgAGBQJbHtKUAAoJECebzXlCjuG+dfgP/2Z9PiJXlxKC2iISgkfMGmBd
MmWZYekYMtCe5raoiI720W5cGL7uBLoKnc+r57+n7bEGxV9OFwtspmKGn17P/zrY
YcBIdN7gjpqn8wrflLR4D09bGpnmaZG26jIt/v0TS+N1aFKO3gNXb0ZVSjUadlI0
UsKRbYxr8qucIENVtXhfA0eRivddadsKopAEwflUrxf+8oEaYszPFUfNXcGDpdHK
+6D2lFjr/Fn+z97Rbz/G3fMfldpYhUOpH28DOiCuKEpgamK3dYjx1WoGUANxcj3o
RsbHGZnMR6842Nj5aHus0k6Ao9bgqt6lx+jKlkvWYK+G2EfMfV9Z1gAipPY+IMbd
Zk5A4pnFpI1UG3sUlcnpaxAM/pHBs7heYGqj0hyocG8rB4V7SDZxp21Lv1fjTH/A
XHAkdiT4iSgI11J8YbmDBR1S7bAnfNm7GT24DsAkZLzh2f5Miq5m/ZMxDxQLAFCJ
3YKo2aNVjKvA/aOKDe5RMLZUhnmuhb8aMIDuQY2Ir1EK4S+7EYOiYAvqlbJrM3Ro
aLmb9BUzRRWmRydMKOeGkWiMj49lHRW6oJxvb33PDZEEqW/AlvmYEyMGfjhXzPDE
OZkvbdYrni4n5YboplxNnJyL0NJ6l5YAikV94SBWBknrnNv1psSZbDKoIgp2ghhQ
rdP842qSmDiZiXVlTr3e
=PuEk
-----END PGP SIGNATURE-----
Merge tag 'nfsd-4.18' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"A relatively quiet cycle for nfsd.
The largest piece is an RDMA update from Chuck Lever with new trace
points, miscellaneous cleanups, and streamlining of the send and
receive paths.
Other than that, some miscellaneous bugfixes"
* tag 'nfsd-4.18' of git://linux-nfs.org/~bfields/linux: (26 commits)
nfsd: fix error handling in nfs4_set_delegation()
nfsd: fix potential use-after-free in nfsd4_decode_getdeviceinfo
Fix 16-byte memory leak in gssp_accept_sec_context_upcall
svcrdma: Fix incorrect return value/type in svc_rdma_post_recvs
svcrdma: Remove unused svc_rdma_op_ctxt
svcrdma: Persistently allocate and DMA-map Send buffers
svcrdma: Simplify svc_rdma_send()
svcrdma: Remove post_send_wr
svcrdma: Don't overrun the SGE array in svc_rdma_send_ctxt
svcrdma: Introduce svc_rdma_send_ctxt
svcrdma: Clean up Send SGE accounting
svcrdma: Refactor svc_rdma_dma_map_buf
svcrdma: Allocate recv_ctxt's on CPU handling Receives
svcrdma: Persistently allocate and DMA-map Receive buffers
svcrdma: Preserve Receive buffer until svc_rdma_sendto
svcrdma: Simplify svc_rdma_recv_ctxt_put
svcrdma: Remove sc_rq_depth
svcrdma: Introduce svc_rdma_recv_ctxt
svcrdma: Trace key RDMA API events
svcrdma: Trace key RPC/RDMA protocol events
...
This crept in during the development process and wasn't caught
before I posted the "final" version.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 0b2613c5883f ('svcrdma: Allocate recv_ctxt's on CPU ... ')
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Stable patches:
- xprtrdma: Return -ENOBUFS when no pages are available
New features:
- Add ->alloc_slot() and ->free_slot() functions
Bugfixes and cleanups:
- Add missing SPDX tags to some files
- Try to fail mount quickly if client has no RDMA devices
- Create transport IDs in the correct network namespace
- Fix max_send_wr computation
- Clean up receive tracepoints
- Refactor receive handling
- Remove unused functions
-----BEGIN PGP SIGNATURE-----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=I9YU
-----END PGP SIGNATURE-----
Merge tag 'nfs-rdma-for-4.18-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
NFS-over-RDMA client updates for Linux 4.18
Stable patches:
- xprtrdma: Return -ENOBUFS when no pages are available
New features:
- Add ->alloc_slot() and ->free_slot() functions
Bugfixes and cleanups:
- Add missing SPDX tags to some files
- Try to fail mount quickly if client has no RDMA devices
- Create transport IDs in the correct network namespace
- Fix max_send_wr computation
- Clean up receive tracepoints
- Refactor receive handling
- Remove unused functions
Clean up: This array was used in a dprintk that was replaced by a
trace point in commit ab03eff58e ("xprtrdma: Add trace points in
RPC Call transmit paths").
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Currently, when the sendctx queue is exhausted during marshaling, the
RPC/RDMA transport places the RPC task on the delayq, which forces a
wait for HZ >> 2 before the marshal and send is retried.
With this change, the transport now places such an RPC task on the
pending queue, and wakes it just as soon as more sendctxs become
available. This typically takes less than a millisecond, and the
write_space waking mechanism is less deadlock-prone.
Moreover, the waiting RPC task is holding the transport's write
lock, which blocks the transport from sending RPCs. Therefore faster
recovery from sendctx queue exhaustion is desirable.
Cf. commit 5804891455d5 ("xprtrdma: ->send_request returns -EAGAIN
when there are no free MRs").
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: The logic to wait for write space is common to a bunch of
the encoding helper functions. Lift it out and put it in the tail
of rpcrdma_marshal_req().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The use of -EAGAIN in rpcrdma_convert_iovs() is a latent bug: the
transport never calls xprt_write_space() when more pages become
available. -ENOBUFS will trigger the correct "delay briefly and call
again" logic.
Fixes: 7a89f9c626 ("xprtrdma: Honor ->send_request API contract")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org # 4.8+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Bugfixes:
- Fix a possible NFSoRDMA list corruption during recovery
- Fix sunrpc tracepoint crashes
Other change:
- Update Trond's email in the MAINTAINERS file
-----BEGIN PGP SIGNATURE-----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=xfe9
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-4.17-2' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client fixes from Anna Schumaker:
"These patches fix both a possible corruption during NFSoRDMA MR
recovery, and a sunrpc tracepoint crash.
Additionally, Trond has a new email address to put in the MAINTAINERS
file"
* tag 'nfs-for-4.17-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
Change Trond's email address in MAINTAINERS
sunrpc: Fix latency trace point crashes
xprtrdma: Fix list corruption / DMAR errors during MR recovery
While sending each RPC Reply, svc_rdma_sendto allocates and DMA-
maps a separate buffer where the RPC/RDMA transport header is
constructed. The buffer is unmapped and released in the Send
completion handler. This is significant per-RPC overhead,
especially for small RPCs.
Instead, allocate and DMA-map a buffer, and cache it in each
svc_rdma_send_ctxt. This buffer and its mapping can be re-used
for each RPC, saving the cost of memory allocation and DMA
mapping.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: No current caller of svc_rdma_send's passes in a chained
WR. The logic that counts the chain length can be replaced with a
constant (1).
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: Now that the send_wr is part of the svc_rdma_send_ctxt,
svc_rdma_post_send_wr is nearly empty.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Receive buffers are always the same size, but each Send WR has a
variable number of SGEs, based on the contents of the xdr_buf being
sent.
While assembling a Send WR, keep track of the number of SGEs so that
we don't exceed the device's maximum, or walk off the end of the
Send SGE array.
For now the Send path just fails if it exceeds the maximum.
The current logic in svc_rdma_accept bases the maximum number of
Send SGEs on the largest NFS request that can be sent or received.
In the transport layer, the limit is actually based on the
capabilities of the underlying device, not on properties of the
Upper Layer Protocol.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
svc_rdma_op_ctxt's are pre-allocated and maintained on a per-xprt
free list. This eliminates the overhead of calling kmalloc / kfree,
both of which grab a globally shared lock that disables interrupts.
Introduce a replacement to svc_rdma_op_ctxt's that is built
especially for the svcrdma Send path.
Subsequent patches will take advantage of this new structure by
allocating real resources which are then cached in these objects.
The allocations are freed when the transport is torn down.
I've renamed the structure so that static type checking can be used
to ensure that uses of op_ctxt and send_ctxt are not confused. As an
additional clean up, structure fields are renamed to conform with
kernel coding conventions.
Additional clean ups:
- Handle svc_rdma_send_ctxt_get allocation failure at each call
site, rather than pre-allocating and hoping we guessed correctly
- All send_ctxt_put call-sites request page freeing, so remove
the @free_pages argument
- All send_ctxt_put call-sites unmap SGEs, so fold that into
svc_rdma_send_ctxt_put
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: Since there's already a svc_rdma_op_ctxt being passed
around with the running count of mapped SGEs, drop unneeded
parameters to svc_rdma_post_send_wr().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: svc_rdma_dma_map_buf does mostly the same thing as
svc_rdma_dma_map_page, so let's fold these together.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There is a significant latency penalty when processing an ingress
Receive if the Receive buffer resides in memory that is not on the
same NUMA node as the the CPU handling completions for a CQ.
The system administrator and the device driver determine which CPU
handles completions. This CPU does not change during life of the CQ.
Further the Upper Layer does not have any visibility of which CPU it
is.
Allocating Receive buffers in the Receive completion handler
guarantees that Receive buffers are allocated on the preferred NUMA
node for that CQ.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The current Receive path uses an array of pages which are allocated
and DMA mapped when each Receive WR is posted, and then handed off
to the upper layer in rqstp::rq_arg. The page flip releases unused
pages in the rq_pages pagelist. This mechanism introduces a
significant amount of overhead.
So instead, kmalloc the Receive buffer, and leave it DMA-mapped
while the transport remains connected. This confers a number of
benefits:
* Each Receive WR requires only one receive SGE, no matter how large
the inline threshold is. This helps the server-side NFS/RDMA
transport operate on less capable RDMA devices.
* The Receive buffer is left allocated and mapped all the time. This
relieves svc_rdma_post_recv from the overhead of allocating and
DMA-mapping a fresh buffer.
* svc_rdma_wc_receive no longer has to DMA unmap the Receive buffer.
It has to DMA sync only the number of bytes that were received.
* svc_rdma_build_arg_xdr no longer has to free a page in rq_pages
for each page in the Receive buffer, making it a constant-time
function.
* The Receive buffer is now plugged directly into the rq_arg's
head[0].iov_vec, and can be larger than a page without spilling
over into rq_arg's page list. This enables simplification of
the RDMA Read path in subsequent patches.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Rather than releasing the incoming svc_rdma_recv_ctxt at the end of
svc_rdma_recvfrom, hold onto it until svc_rdma_sendto.
This permits the contents of the Receive buffer to be preserved
through svc_process and then referenced directly in sendto as it
constructs Write and Reply chunks to return to the client.
The real changes will come in subsequent patches.
Note: I cannot use ->xpo_release_rqst for this purpose because that
is called _before_ ->xpo_sendto. svc_rdma_sendto uses information in
the received Call transport header to construct the Reply transport
header, which is preserved in the RPC's Receive buffer.
The historical comment in svc_send() isn't helpful: it is already
obvious that ->xpo_release_rqst is being called before ->xpo_sendto,
but there is no explanation for this ordering going back to the
beginning of the git era.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently svc_rdma_recv_ctxt_put's callers have to know whether they
want to free the ctxt's pages or not. This means the human
developers have to know when and why to set that free_pages
argument.
Instead, the ctxt should carry that information with it so that
svc_rdma_recv_ctxt_put does the right thing no matter who is
calling.
We want to keep track of the number of pages in the Receive buffer
separately from the number of pages pulled over by RDMA Read. This
is so that the correct number of pages can be freed properly and
that number is well-documented.
So now, rc_hdr_count is the number of pages consumed by head[0]
(ie., the page index where the Read chunk should start); and
rc_page_count is always the number of pages that need to be released
when the ctxt is put.
The @free_pages argument is no longer needed.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: No need to retain rq_depth in struct svcrdma_xprt, it is
used only in svc_rdma_accept().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
svc_rdma_op_ctxt's are pre-allocated and maintained on a per-xprt
free list. This eliminates the overhead of calling kmalloc / kfree,
both of which grab a globally shared lock that disables interrupts.
To reduce contention further, separate the use of these objects in
the Receive and Send paths in svcrdma.
Subsequent patches will take advantage of this separation by
allocating real resources which are then cached in these objects.
The allocations are freed when the transport is torn down.
I've renamed the structure so that static type checking can be used
to ensure that uses of op_ctxt and recv_ctxt are not confused. As an
additional clean up, structure fields are renamed to conform with
kernel coding conventions.
As a final clean up, helpers related to recv_ctxt are moved closer
to the functions that use them.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This includes:
* Posting on the Send and Receive queues
* Send, Receive, Read, and Write completion
* Connect upcalls
* QP errors
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This includes:
* Transport accept and tear-down
* Decisions about using Write and Reply chunks
* Each RDMA segment that is handled
* Whenever an RDMA_ERR is sent
As a clean-up, I've standardized the order of the includes, and
removed some now redundant dprintk call sites.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: Move #include <trace/events/rpcrdma.h> into source files,
similar to how it is done with trace/events/sunrpc.h.
Server-side trace points will be part of the rpcrdma subsystem,
just like the client-side trace points.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Ensure each RDMA listener and its children transports are created in
the same net namespace as the user that started the NFS service.
This is similar to how listener sockets are created in
svc_create_socket, required for enabling support for containers.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: The only call site is in the same file as the function's
definition.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: There is only one remaining call site for this helper.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up. There is only one call-site for this helper, and it can be
simplified by using list_first_entry_or_null().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: These functions are no longer used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Receive completion and Reply handling are done by a BOUND
workqueue, meaning they run on only one CPU.
Posting receives is currently done in the send_request path, which
on large systems is typically done on a different CPU than the one
handling Receive completions. This results in movement of
Receive-related cachelines between the sending and receiving CPUs.
More importantly, it means that currently Receives are posted while
the transport's write lock is held, which is unnecessary and costly.
Finally, allocation of Receive buffers is performed on-demand in
the Receive completion handler. This helps guarantee that they are
allocated on the same NUMA node as the CPU that handles Receive
completions.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
For clarity, report the posting and completion of Receive CQEs.
Also, the wc->byte_len field contains garbage if wc->status is
non-zero, and the vendor error field contains garbage if wc->status
is zero. For readability, don't save those fields in those cases.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This simplifies allocation of the generic RPC slot and xprtrdma
specific per-RPC resources.
It also makes xprtrdma more like the socket-based transports:
->buf_alloc and ->buf_free are now responsible only for send and
receive buffers.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
rpcrdma_buffer_get acquires an rpcrdma_req and rep for each RPC.
Currently this is done in the call_allocate action, and sometimes it
can fail if there are many outstanding RPCs.
When call_allocate fails, the RPC task is put on the delayq. It is
awoken a few milliseconds later, but there's no guarantee it will
get a buffer at that time. The RPC task can be repeatedly put back
to sleep or even starved.
The call_allocate action should rarely fail. The delayq mechanism is
not meant to deal with transport congestion.
In the current sunrpc stack, there is a friendlier way to deal with
this situation. These objects are actually tantamount to an RPC
slot (rpc_rqst) and there is a separate FSM action, distinct from
call_allocate, for allocating slot resources. This is the
call_reserve action.
When allocation fails during this action, the RPC is placed on the
transport's backlog queue. The backlog mechanism provides a stronger
guarantee that when the RPC is awoken, a buffer will be available
for it; and backlogged RPCs are awoken one-at-a-time.
To make slot resource allocation occur in the call_reserve action,
create special ->alloc_slot and ->free_slot call-outs for xprtrdma.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Refactor: xprtrdma needs to have better control over when RPCs are
awoken from the backlog queue, so replace xprt_free_slot with a
transport op callout.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
For FRWR, the computation of max_send_wr is split between
frwr_op_open and rpcrdma_ep_create, which makes it difficult to tell
that the max_send_wr result is currently incorrect if frwr_op_open
has to reduce the credit limit to accommodate a small max_qp_wr.
This is a problem now that extra WRs are needed for backchannel
operations and a drain CQE.
So, refactor the computation so that it is all done in ->ro_open,
and fix the FRWR version of this computation so that it
accommodates HCAs with small max_qp_wr correctly.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Set up RPC/RDMA transport in mount.nfs's network namespace. This
passes the correct namespace information to the RDMA core, similar
to how RPC sockets are created (see xs_create_sock).
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
rdma_resolve_addr(3) says:
> This call is used to map a given destination IP address to a
> usable RDMA address. The IP to RDMA address mapping is done
> using the local routing tables, or via ARP.
If this can't be done, there's no local device that can be used
to establish an RDMA-capable network path to the remote. In this
case, the RDMA CM very quickly posts an RDMA_CM_EVENT_ADDR_ERROR
upcall.
Currently rpcrdma_conn_upcall() converts RDMA_CM_EVENT_ADDR_ERROR
to EHOSTUNREACH. mount.nfs seems to want to retry EHOSTUNREACH
forever, thinking that this is a temporary situation. This makes
mount.nfs appear to hang if I try to mount with proto=rdma through,
say, a conventional Ethernet device.
If the admin has specified proto=rdma along with a server IP address
that requires a network path that does not support RDMA, instead
let's fail with a permanent error. -EPROTONOSUPPORT is returned when
NFSv4 or one of its minor versions is not supported.
-EPROTO is not (currently) retried by mount.nfs.
There are potentially other similar cases where -EPROTO is an
appropriate return code.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Olga Kornievskaia <kolga@netapp.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The ro_release_mr methods check whether mr->mr_list is empty.
Therefore, be sure to always use list_del_init when removing an MR
linked into a list using that field. Otherwise, when recovering from
transport failures or device removal, list corruption can result, or
MRs can get mapped or unmapped an odd number of times, resulting in
IOMMU-related failures.
In general this fix is appropriate back to v4.8. However, code
changes since then make it impossible to apply this patch directly
to stable kernels. The fix would have to be applied by hand or
reworked for kernels earlier than v4.16.
Backport guidance -- there are several cases:
- When creating an MR, initialize mr_list so that using list_empty
on an as-yet-unused MR is safe.
- When an MR is being handled by the remote invalidation path,
ensure that mr_list is reinitialized when it is removed from
rl_registered.
- When an MR is being handled by rpcrdma_destroy_mrs, it is removed
from mr_all, but it may still be on an rl_registered list. In
that case, the MR needs to be removed from that list before being
released.
- Other cases are covered by using list_del_init in rpcrdma_mr_pop.
Fixes: 9d6b040978 ('xprtrdma: Place registered MWs on a ... ')
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Stable bugfixes:
- xprtrdma: Fix corner cases when handling device removal # v4.12+
- xprtrdma: Fix latency regression on NUMA NFS/RDMA clients # v4.15+
Features:
- New sunrpc tracepoint for RPC pings
- Finer grained NFSv4 attribute checking
- Don't unnecessarily return NFS v4 delegations
Other bugfixes and cleanups:
- Several other small NFSoRDMA cleanups
- Improvements to the sunrpc RTT measurements
- A few sunrpc tracepoint cleanups
- Various fixes for NFS v4 lock notifications
- Various sunrpc and NFS v4 XDR encoding cleanups
- Switch to the ida_simple API
- Fix NFSv4.1 exclusive create
- Forget acl cache after setattr operation
- Don't advance the nfs_entry readdir cookie if xdr decoding fails
-----BEGIN PGP SIGNATURE-----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=IlWo
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-4.17-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client updates from Anna Schumaker:
"Stable bugfixes:
- xprtrdma: Fix corner cases when handling device removal # v4.12+
- xprtrdma: Fix latency regression on NUMA NFS/RDMA clients # v4.15+
Features:
- New sunrpc tracepoint for RPC pings
- Finer grained NFSv4 attribute checking
- Don't unnecessarily return NFS v4 delegations
Other bugfixes and cleanups:
- Several other small NFSoRDMA cleanups
- Improvements to the sunrpc RTT measurements
- A few sunrpc tracepoint cleanups
- Various fixes for NFS v4 lock notifications
- Various sunrpc and NFS v4 XDR encoding cleanups
- Switch to the ida_simple API
- Fix NFSv4.1 exclusive create
- Forget acl cache after setattr operation
- Don't advance the nfs_entry readdir cookie if xdr decoding fails"
* tag 'nfs-for-4.17-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (47 commits)
NFS: advance nfs_entry cookie only after decoding completes successfully
NFSv3/acl: forget acl cache after setattr
NFSv4.1: Fix exclusive create
NFSv4: Declare the size up to date after it was set.
nfs: Use ida_simple API
NFSv4: Fix the nfs_inode_set_delegation() arguments
NFSv4: Clean up CB_GETATTR encoding
NFSv4: Don't ask for attributes when ACCESS is protected by a delegation
NFSv4: Add a helper to encode/decode struct timespec
NFSv4: Clean up encode_attrs
NFSv4; Clean up XDR encoding of type bitmap4
NFSv4: Allow GFP_NOIO sleeps in decode_attr_owner/decode_attr_group
SUNRPC: Add a helper for encoding opaque data inline
SUNRPC: Add helpers for decoding opaque and string types
NFSv4: Ignore change attribute invalidations if we hold a delegation
NFS: More fine grained attribute tracking
NFS: Don't force unnecessary cache invalidation in nfs_update_inode()
NFS: Don't redirty the attribute cache in nfs_wcc_update_inode()
NFS: Don't force a revalidation of all attributes if change is missing
NFS: Convert NFS_INO_INVALID flags to unsigned long
...
Michal Kalderon has found some corner cases around device unload
with active NFS mounts that I didn't have the imagination to test
when xprtrdma device removal was added last year.
- The ULP device removal handler is responsible for deallocating
the PD. That wasn't clear to me initially, and my own testing
suggested it was not necessary, but that is incorrect.
- The transport destruction path can no longer assume that there
is a valid ID.
- When destroying a transport, ensure that ib_free_cq() is not
invoked on a CQ that was already released.
Reported-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Fixes: bebd031866 ("xprtrdma: Support unplugging an HCA from ...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Some RPC transports have more overhead in their send_request
callouts than others. For example, for RPC-over-RDMA:
- Marshaling an RPC often has to DMA map the RPC arguments
- Registration methods perform memory registration as part of
marshaling
To capture just server and network latencies more precisely: when
sending a Call, capture the rq_xtime timestamp _after_ the transport
header has been marshaled.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Refactor: Both rpcrdma_create_req call sites have to allocate the
buffer where the transport header is built, so just move that
allocation into rpcrdma_create_req.
This buffer is a fixed size. There's no needed information available
in call_allocate that is not also available when the transport is
created.
The original purpose for allocating these buffers on demand was to
reduce the possibility that an allocation failure during transport
creation will hork the mount operation during low memory scenarios.
Some relief for this rare possibility is coming up in the next few
patches.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
With FRWR, the client transport can perform memory registration and
post a Send with just a single ib_post_send.
This reduces contention between the send_request path and the Send
Completion handlers, and reduces the overhead of registering a chunk
that has multiple segments.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
RPC-over-RDMA version 1 credit accounting relies on there being a
response message for every RPC Call. This means that RPC procedures
that have no reply will disrupt credit accounting, just in the same
way as a retransmit would (since it is sent because no reply has
arrived). Deal with the "no reply" case the same way.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Create fewer MRs on average. Many workloads don't need as many as
32 MRs, and the transport can now quickly restock the MR free list.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Currently, when the MR free list is exhausted during marshaling, the
RPC/RDMA transport places the RPC task on the delayq, which forces a
wait for HZ >> 2 before the marshal and send is retried.
With this change, the transport now places such an RPC task on the
pending queue, and wakes it just as soon as more MRs have been
created. Creating more MRs typically takes less than a millisecond,
and this waking mechanism is less deadlock-prone.
Moreover, the waiting RPC task is holding the transport's write
lock, which blocks the transport from sending RPCs. Therefore faster
recovery from MR exhaustion is desirable.
This is the same mechanism that the TCP transport utilizes when
handling write buffer space exhaustion.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: The generic rq_connect_cookie is sufficient to detect RPC
Call retransmission.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: We need to check only that the value does not exceed the
range of the u8 field it's going into.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
With v4.15, on one of my NFS/RDMA clients I measured a nearly
doubling in the latency of small read and write system calls. There
was no change in server round trip time. The extra latency appears
in the whole RPC execution path.
"git bisect" settled on commit ccede75985 ("xprtrdma: Spread reply
processing over more CPUs") .
After some experimentation, I found that leaving the WQ bound and
allowing the scheduler to pick the dispatch CPU seems to eliminate
the long latencies, and it does not introduce any new regressions.
The fix is implemented by reverting only the part of
commit ccede75985 ("xprtrdma: Spread reply processing over more
CPUs") that dispatches RPC replies specifically on the CPU where the
matching RPC call was made.
Interestingly, saving the CPU number and later queuing reply
processing there was effective _only_ for a NFS READ and WRITE
request. On my NUMA client, in-kernel RPC reply processing for
asynchronous RPCs was dispatched on the same CPU where the RPC call
was made, as expected. However synchronous RPCs seem to get their
reply dispatched on some other CPU than where the call was placed,
every time.
Fixes: ccede75985 ("xprtrdma: Spread reply processing over ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org # v4.15+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
TP_printk defines a format string that is passed to user space for
converting raw trace event records to something human-readable.
My user space's printf (Oracle Linux 7), however, does not have a
%pI format specifier. The result is that what is supposed to be an
IP address in the output of "trace-cmd report" is just a string that
says the field couldn't be displayed.
To fix this, adopt the same approach as the client: maintain a pre-
formated presentation address for occasions when %pI is not
available.
The location of the trace_svc_send trace point is adjusted so that
rqst->rq_xprt is not NULL when the trace event is recorded.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: Instead of returning a value that is used to set or clear
a bit, just make ->xpo_secure_port mangle that bit, and return void.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: The value of the byte_count parameter is already passed
to rdma_build_arg_xdr as part of the svc_rdma_op_ctxt structure.
Further, without the parameter called "byte_count" there is no need
to have the abbreviated "bc" automatic variable. "bc" can now be
called something more intuitive.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The target needs to return the lesser of the client's Inbound RDMA
Read Queue Depth (IRD), provided in the connection parameters, and
the local device's Outbound RDMA Read Queue Depth (ORD). The latter
limit is max_qp_init_rd_atom, not max_qp_rd_atom.
The svcrdma_ord value caps the ORD value for iWARP transports, which
do not exchange ORD/IRD values at connection time. Since no other
Linux kernel RDMA-enabled storage target sees fit to provide this
cap, I'm removing it here too.
initiator_depth is a u8, so ensure the computed ORD value does not
overflow that field.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: Other completion handlers use pr_err, not pr_warn.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Hightlights include:
Stable fixes:
- Fix an incorrect calculation of the RDMA send scatter gather element limit
- Fix an Oops when attempting to free resources after RDMA device removal
Bugfixes:
- SUNRPC: Ensure we always release the TCP socket in a timely fashion when
the connection is shut down.
- SUNRPC: Don't call __UDPX_INC_STATS() from a preemptible context
Latency/Performance:
- SUNRPC: Queue latency sensitive socket tasks to the less contended
xprtiod queue
- SUNRPC: Make the xprtiod workqueue unbounded.
- SUNRPC: Make the rpciod workqueue unbounded
-----BEGIN PGP SIGNATURE-----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=KST7
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-4.16-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull more NFS client updates from Trond Myklebust:
"A few bugfixes and some small sunrpc latency/performance improvements
before the merge window closes:
Stable fixes:
- fix an incorrect calculation of the RDMA send scatter gather
element limit
- fix an Oops when attempting to free resources after RDMA device
removal
Bugfixes:
- SUNRPC: Ensure we always release the TCP socket in a timely fashion
when the connection is shut down.
- SUNRPC: Don't call __UDPX_INC_STATS() from a preemptible context
Latency/Performance:
- SUNRPC: Queue latency sensitive socket tasks to the less contended
xprtiod queue
- SUNRPC: Make the xprtiod workqueue unbounded.
- SUNRPC: Make the rpciod workqueue unbounded"
* tag 'nfs-for-4.16-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
SUNRPC: Don't call __UDPX_INC_STATS() from a preemptible context
fix parallelism for rpc tasks
Make the xprtiod workqueue unbounded.
SUNRPC: Queue latency-sensitive socket tasks to xprtiod
SUNRPC: Ensure we always close the socket after a connection shuts down
xprtrdma: Fix BUG after a device removal
xprtrdma: Fix calculation of ri_max_send_sges
But it's also a fairly small update this time around. Some cleanup,
RDMA fixes, overlayfs fixes, and a fix for an NFSv4 state bug.
The bigger deal for nfsd this time around is Jeff Layton's
already-merged i_version patches. This series has a minor conflict with
that one, and the resolution should be obvious. (Stephen Rothwell has
been carrying it in linux-next for what it's worth.)
-----BEGIN PGP SIGNATURE-----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=icEX
-----END PGP SIGNATURE-----
Merge tag 'nfsd-4.16' of git://linux-nfs.org/~bfields/linux
Pull nfsd update from Bruce Fields:
"A fairly small update this time around. Some cleanup, RDMA fixes,
overlayfs fixes, and a fix for an NFSv4 state bug.
The bigger deal for nfsd this time around was Jeff Layton's
already-merged i_version patches"
* tag 'nfsd-4.16' of git://linux-nfs.org/~bfields/linux:
svcrdma: Fix Read chunk round-up
NFSD: hide unused svcxdr_dupstr()
nfsd: store stat times in fill_pre_wcc() instead of inode times
nfsd: encode stat->mtime for getattr instead of inode->i_mtime
nfsd: return RESOURCE not GARBAGE_ARGS on too many ops
nfsd4: don't set lock stateid's sc_type to CLOSED
nfsd: Detect unhashed stids in nfsd4_verify_open_stid()
sunrpc: remove dead code in svc_sock_setbufsize
svcrdma: Post Receives in the Receive completion handler
nfsd4: permit layoutget of executable-only files
lockd: convert nlm_rqst.a_count from atomic_t to refcount_t
lockd: convert nlm_lockowner.count from atomic_t to refcount_t
lockd: convert nsm_handle.sm_count from atomic_t to refcount_t
A single NFSv4 WRITE compound can often have three operations:
PUTFH, WRITE, then GETATTR.
When the WRITE payload is sent in a Read chunk, the client places
the GETATTR in the inline part of the RPC/RDMA message, just after
the WRITE operation (sans payload). The position value in the Read
chunk enables the receiver to insert the Read chunk at the correct
place in the received XDR stream; that is between the WRITE and
GETATTR.
According to RFC 8166, an NFS/RDMA client does not have to add XDR
round-up to the Read chunk that carries the WRITE payload. The
receiver adds XDR round-up padding if it is absent and the
receiver's XDR decoder requires it to be present.
Commit 193bcb7b37 ("svcrdma: Populate tail iovec when receiving")
attempted to add support for receiving such a compound so that just
the WRITE payload appears in rq_arg's page list, and the trailing
GETATTR is placed in rq_arg's tail iovec. (TCP just strings the
whole compound into the head iovec and page list, without regard
to the alignment of the WRITE payload).
The server transport logic also had to accommodate the optional XDR
round-up of the Read chunk, which it did simply by lengthening the
tail iovec when round-up was needed. This approach is adequate for
the NFSv2 and NFSv3 WRITE decoders.
Unfortunately it is not sufficient for nfsd4_decode_write. When the
Read chunk length is a couple of bytes less than PAGE_SIZE, the
computation at the end of nfsd4_decode_write allows argp->pagelen to
go negative, which breaks the logic in read_buf that looks for the
tail iovec.
The result is that a WRITE operation whose payload length is just
less than a multiple of a page succeeds, but the subsequent GETATTR
in the same compound fails with NFS4ERR_OP_ILLEGAL because the XDR
decoder can't find it. Clients ignore the error, but they must
update their attribute cache via a separate round trip.
As nfsd4_decode_write appears to expect the payload itself to always
have appropriate XDR round-up, have svc_rdma_build_normal_read_chunk
add the Read chunk XDR round-up to the page_len rather than
lengthening the tail iovec.
Reported-by: Olga Kornievskaia <kolga@netapp.com>
Fixes: 193bcb7b37 ("svcrdma: Populate tail iovec when receiving")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Michal Kalderon reports a BUG that occurs just after device removal:
[ 169.112490] rpcrdma: removing device qedr0 for 192.168.110.146:20049
[ 169.143909] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
[ 169.181837] IP: rpcrdma_dma_unmap_regbuf+0xa/0x60 [rpcrdma]
The RPC/RDMA client transport attempts to allocate some resources
on demand. Registered buffers are one such resource. These are
allocated (or re-allocated) by xprt_rdma_allocate to hold RPC Call
and Reply messages. A hardware resource is associated with each of
these buffers, as they can be used for a Send or Receive Work
Request.
If a device is removed from under an NFS/RDMA mount, the transport
layer is responsible for releasing all hardware resources before
the device can be finally unplugged. A BUG results when the NFS
mount hasn't yet seen much activity: the transport tries to release
resources that haven't yet been allocated.
rpcrdma_free_regbuf() already checks for this case, so just move
that check to cover the DEVICE_REMOVAL case as well.
Reported-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Fixes: bebd031866 ("xprtrdma: Support unplugging an HCA ...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Commit 16f906d66c ("xprtrdma: Reduce required number of send
SGEs") introduced the rpcrdma_ia::ri_max_send_sges field. This fixes
a problem where xprtrdma would not work if the device's max_sge
capability was small (low single digits).
At least RPCRDMA_MIN_SEND_SGES are needed for the inline parts of
each RPC. ri_max_send_sges is set to this value:
ia->ri_max_send_sges = max_sge - RPCRDMA_MIN_SEND_SGES;
Then when marshaling each RPC, rpcrdma_args_inline uses that value
to determine whether the device has enough Send SGEs to convey an
NFS WRITE payload inline, or whether instead a Read chunk is
required.
More recently, commit ae72950abf ("xprtrdma: Add data structure to
manage RDMA Send arguments") used the ri_max_send_sges value to
calculate the size of an array, but that commit erroneously assumed
ri_max_send_sges contains a value similar to the device's max_sge,
and not one that was reduced by the minimum SGE count.
This assumption results in the calculated size of the sendctx's
Send SGE array to be too small. When the array is used to marshal
an RPC, the code can write Send SGEs into the following sendctx
element in that array, corrupting it. When the device's max_sge is
large, this issue is entirely harmless; but it results in an oops
in the provider's post_send method, if dev.attrs.max_sge is small.
So let's straighten this out: ri_max_send_sges will now contain a
value with the same meaning as dev.attrs.max_sge, which makes
the code easier to understand, and enables rpcrdma_sendctx_create
to calculate the size of the SGE array correctly.
Reported-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Fixes: 16f906d66c ("xprtrdma: Reduce required number of send SGEs")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Cc: stable@vger.kernel.org # v4.10+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Track RPC timeouts: report the XID and the server address to match
the content of network capture.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Fix kernel-doc warnings in net/sunrpc/xprtrdma/ .
net/sunrpc/xprtrdma/verbs.c:1575: warning: No description found for parameter 'count'
net/sunrpc/xprtrdma/verbs.c:1575: warning: Excess function parameter 'min_reqs' description in 'rpcrdma_ep_post_extra_recv'
net/sunrpc/xprtrdma/backchannel.c:288: warning: No description found for parameter 'r_xprt'
net/sunrpc/xprtrdma/backchannel.c:288: warning: Excess function parameter 'xprt' description in 'rpcrdma_bc_receive_call'
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The contents of seg->mr_len changed when ->ro_map stopped returning
the full chunk length in the first segment. Count the full length of
each Write chunk, not the length of the first segment (which now can
only be as large as a page).
Fixes: 9d6b040978 ("xprtrdma: Place registered MWs on a ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This includes decoding Write and Reply chunks, and fixing up inline
payloads.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This change improves Receive efficiency by posting Receives only
on the same CPU that handles Receive completion. Improved latency
and throughput has been noted with this change.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: Code review suggested that a common bit of code can be
placed into a helper function, and this gives us fewer places to
stick an "I DMA unmapped something" trace point.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: struct rpcrdma_mw was named after Memory Windows, but
xprtrdma no longer supports a Memory Window registration mode.
Rename rpcrdma_mw and its fields to reduce confusion and make
the code more sensible to read.
Renaming "mw" was suggested by Tom Talpey, the author of the
original xprtrdma implementation. It's a good idea, but I haven't
done this until now because it's a huge diffstat for no benefit
other than code readability.
However, I'm about to introduce static trace points that expose
a few of xprtrdma's internal data structures. They should make sense
in the trace report, and it's reasonable to treat trace points as a
kernel API contract which might be difficult to change later.
While I'm churning things up, two additional changes:
- rename variables unhelpfully called "r" to "mr", to improve code
clarity, and
- rename the MR-related helper functions using the form
"rpcrdma_mr_<verb>", to be consistent with other areas of the
code.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Over time, the industry has adopted the term "frwr"
instead of "frmr". The term "frwr" is now more widely recognized.
For the past couple of years I've attempted to add new code using
"frwr" , but there still remains plenty of older code that still
uses "frmr". Replace all usage of "frmr" to avoid confusion.
While we're churning code, rename variables unhelpfully called "f"
to "frwr", to improve code clarity.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
No need for the overhead of atomically setting and clearing this bit
flag for every use of a pre-allocated backchannel rpc_rqst. These
are a distinct pool of rpc_rqsts that are used only for callback
operations, so it is safe to simply leave the bit set.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Chuck Lever