Highlights include:
Stable fixes:
- SUNRPC: Ensure we flush any closed sockets before xs_xprt_free()
Bugfixes:
- Fix an Oopsable condition due to SLAB_ACCOUNT setting in the NFSv4.2
xattr code.
- Fix for open() using an file open mode of '3' in NFSv4
- Replace readdir's use of xxhash() with hash_64()
- Several patches to handle malloc() failure in SUNRPC
-----BEGIN PGP SIGNATURE-----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=edfs
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-5.18-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client fixes from Trond Myklebust:
"Stable fixes:
- SUNRPC: Ensure we flush any closed sockets before xs_xprt_free()
Bugfixes:
- Fix an Oopsable condition due to SLAB_ACCOUNT setting in the
NFSv4.2 xattr code.
- Fix for open() using an file open mode of '3' in NFSv4
- Replace readdir's use of xxhash() with hash_64()
- Several patches to handle malloc() failure in SUNRPC"
* tag 'nfs-for-5.18-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
SUNRPC: Move the call to xprt_send_pagedata() out of xprt_sock_sendmsg()
SUNRPC: svc_tcp_sendmsg() should handle errors from xdr_alloc_bvec()
SUNRPC: Handle allocation failure in rpc_new_task()
NFS: Ensure rpc_run_task() cannot fail in nfs_async_rename()
NFSv4/pnfs: Handle RPC allocation errors in nfs4_proc_layoutget
SUNRPC: Handle low memory situations in call_status()
SUNRPC: Handle ENOMEM in call_transmit_status()
NFSv4.2: Fix missing removal of SLAB_ACCOUNT on kmem_cache allocation
SUNRPC: Ensure we flush any closed sockets before xs_xprt_free()
NFS: Replace readdir's use of xxhash() with hash_64()
SUNRPC: handle malloc failure in ->request_prepare
NFSv4: fix open failure with O_ACCMODE flag
Revert "NFSv4: Handle the special Linux file open access mode"
We must ensure that all sockets are closed before we call xprt_free()
and release the reference to the net namespace. The problem is that
calling fput() will defer closing the socket until delayed_fput() gets
called.
Let's fix the situation by allowing rpciod and the transport teardown
code (which runs on the system wq) to call __fput_sync(), and directly
close the socket.
Reported-by: Felix Fu <foyjog@gmail.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Fixes: a73881c96d ("SUNRPC: Fix an Oops in udp_poll()")
Cc: stable@vger.kernel.org # 5.1.x: 3be232f11a: SUNRPC: Prevent immediate close+reconnect
Cc: stable@vger.kernel.org # 5.1.x: 89f42494f9: SUNRPC: Don't call connect() more than once on a TCP socket
Cc: stable@vger.kernel.org # 5.1.x
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If ->request_prepare() detects an error, it sets ->rq_task->tk_status.
This is easy for callers to ignore.
The only caller is xprt_request_enqueue_receive() and it does ignore the
error, as does call_encode() which calls it. This can result in a
request being queued to receive a reply without an allocated receive buffer.
So instead of setting rq_task->tk_status, return an error, and store in
->tk_status only in call_encode();
The call to xprt_request_enqueue_receive() is now earlier in
call_encode(), where the error can still be handled.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Highlights include:
Features:
- Switch NFS to use readahead instead of the obsolete readpages.
- Readdir fixes to improve cacheability of large directories when there
are multiple readers and writers.
- Readdir performance improvements when doing a seekdir() immediately
after opening the directory (common when re-exporting NFS).
- NFS swap improvements from Neil Brown.
- Loosen up memory allocation to permit direct reclaim and write back
in cases where there is no danger of deadlocking the writeback code or
NFS swap.
- Avoid sillyrename when the NFSv4 server claims to support the
necessary features to recover the unlinked but open file after reboot.
Bugfixes:
- Patch from Olga to add a mount option to control NFSv4.1 session
trunking discovery, and default it to being off.
- Fix a lockup in nfs_do_recoalesce().
- Two fixes for list iterator variables being used when pointing to the
list head.
- Fix a kernel memory scribble when reading from a non-socket transport
in /sys/kernel/sunrpc.
- Fix a race where reconnecting to a server could leave the TCP socket
stuck forever in the connecting state.
- Patch from Neil to fix a shutdown race which can leave the SUNRPC
transport timer primed after we free the struct xprt itself.
- Patch from Xin Xiong to fix reference count leaks in the NFSv4.2 copy
offload.
- Sunrpc patch from Olga to avoid resending a task on an offlined
transport.
Cleanups:
- Patches from Dave Wysochanski to clean up the fscache code
-----BEGIN PGP SIGNATURE-----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=jeGt
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-5.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Features:
- Switch NFS to use readahead instead of the obsolete readpages.
- Readdir fixes to improve cacheability of large directories when
there are multiple readers and writers.
- Readdir performance improvements when doing a seekdir() immediately
after opening the directory (common when re-exporting NFS).
- NFS swap improvements from Neil Brown.
- Loosen up memory allocation to permit direct reclaim and write back
in cases where there is no danger of deadlocking the writeback code
or NFS swap.
- Avoid sillyrename when the NFSv4 server claims to support the
necessary features to recover the unlinked but open file after
reboot.
Bugfixes:
- Patch from Olga to add a mount option to control NFSv4.1 session
trunking discovery, and default it to being off.
- Fix a lockup in nfs_do_recoalesce().
- Two fixes for list iterator variables being used when pointing to
the list head.
- Fix a kernel memory scribble when reading from a non-socket
transport in /sys/kernel/sunrpc.
- Fix a race where reconnecting to a server could leave the TCP
socket stuck forever in the connecting state.
- Patch from Neil to fix a shutdown race which can leave the SUNRPC
transport timer primed after we free the struct xprt itself.
- Patch from Xin Xiong to fix reference count leaks in the NFSv4.2
copy offload.
- Sunrpc patch from Olga to avoid resending a task on an offlined
transport.
Cleanups:
- Patches from Dave Wysochanski to clean up the fscache code"
* tag 'nfs-for-5.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (91 commits)
NFSv4/pNFS: Fix another issue with a list iterator pointing to the head
NFS: Don't loop forever in nfs_do_recoalesce()
SUNRPC: Don't return error values in sysfs read of closed files
SUNRPC: Do not dereference non-socket transports in sysfs
NFSv4.1: don't retry BIND_CONN_TO_SESSION on session error
SUNRPC don't resend a task on an offlined transport
NFS: replace usage of found with dedicated list iterator variable
SUNRPC: avoid race between mod_timer() and del_timer_sync()
pNFS/files: Ensure pNFS allocation modes are consistent with nfsiod
pNFS/flexfiles: Ensure pNFS allocation modes are consistent with nfsiod
NFSv4/pnfs: Ensure pNFS allocation modes are consistent with nfsiod
NFS: Avoid writeback threads getting stuck in mempool_alloc()
NFS: nfsiod should not block forever in mempool_alloc()
SUNRPC: Make the rpciod and xprtiod slab allocation modes consistent
SUNRPC: Fix unx_lookup_cred() allocation
NFS: Fix memory allocation in rpc_alloc_task()
NFS: Fix memory allocation in rpc_malloc()
SUNRPC: Improve accuracy of socket ENOBUFS determination
SUNRPC: Replace internal use of SOCKWQ_ASYNC_NOSPACE
SUNRPC: Fix socket waits for write buffer space
...
xprt_destory() claims XPRT_LOCKED and then calls del_timer_sync().
Both xprt_unlock_connect() and xprt_release() call
->release_xprt()
which drops XPRT_LOCKED and *then* xprt_schedule_autodisconnect()
which calls mod_timer().
This may result in mod_timer() being called *after* del_timer_sync().
When this happens, the timer may fire long after the xprt has been freed,
and run_timer_softirq() will probably crash.
The pairing of ->release_xprt() and xprt_schedule_autodisconnect() is
always called under ->transport_lock. So if we take ->transport_lock to
call del_timer_sync(), we can be sure that mod_timer() will run first
(if it runs at all).
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
rpc tasks can be marked as RPC_TASK_SWAPPER. This causes GFP_MEMALLOC
to be used for some allocations. This is needed in some cases, but not
in all where it is currently provided, and in some where it isn't
provided.
Currently *all* tasks associated with a rpc_client on which swap is
enabled get the flag and hence some GFP_MEMALLOC support.
GFP_MEMALLOC is provided for ->buf_alloc() but only swap-writes need it.
However xdr_alloc_bvec does not get GFP_MEMALLOC - though it often does
need it.
xdr_alloc_bvec is called while the XPRT_LOCK is held. If this blocks,
then it blocks all other queued tasks. So this allocation needs
GFP_MEMALLOC for *all* requests, not just writes, when the xprt is used
for any swap writes.
Similarly, if the transport is not connected, that will block all
requests including swap writes, so memory allocations should get
GFP_MEMALLOC if swap writes are possible.
So with this patch:
1/ we ONLY set RPC_TASK_SWAPPER for swap writes.
2/ __rpc_execute() sets PF_MEMALLOC while handling any task
with RPC_TASK_SWAPPER set, or when handling any task that
holds the XPRT_LOCKED lock on an xprt used for swap.
This removes the need for the RPC_IS_SWAPPER() test
in ->buf_alloc handlers.
3/ xprt_prepare_transmit() sets PF_MEMALLOC after locking
any task to a swapper xprt. __rpc_execute() will clear it.
3/ PF_MEMALLOC is set for all the connect workers.
Reviewed-by: Chuck Lever <chuck.lever@oracle.com> (for xprtrdma parts)
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Currently, tasks marked as "swapper" tasks get put to the front of
non-priority rpc_queues, and are sorted earlier than non-swapper tasks on
the transport's ->xmit_queue.
This is pointless as currently *all* tasks for a mount that has swap
enabled on *any* file are marked as "swapper" tasks. So the net result
is that the non-priority rpc_queues are reverse-ordered (LIFO).
This scheduling boost is not necessary to avoid deadlocks, and hurts
fairness, so remove it. If there were a need to expedite some requests,
the tk_priority mechanism is a more appropriate tool.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When memory is short, new worker threads cannot be created and we depend
on the minimum one rpciod thread to be able to handle everything. So it
must not block waiting for memory.
xprt_dynamic_alloc_slot can block indefinitely. This can tie up all
workqueue threads and NFS can deadlock. So when called from a
workqueue, set __GFP_NORETRY.
The rdma alloc_slot already does not block. However it sets the error
to -EAGAIN suggesting this will trigger a sleep. It does not. As we
can see in call_reserveresult(), only -ENOMEM causes a sleep. -EAGAIN
causes immediate retry.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The sections which should not re-enter the filesystem are already
protected with memalloc_nofs_save/restore calls, so it is better to use
GFP_KERNEL in these calls to allow better performance for synchronous
RPC calls.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If we have already set up the socket and are waiting for it to connect,
then don't immediately close and retry.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Ensure that we bump the xprt->connect_cookie when we set the
XPRT_CLOSE_WAIT flag so that another call to
xprt_conditional_disconnect() won't race with the reconnection.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The clearing of the XPRT_LOCKED bit has to happen after we clear
xprt->snd_task, but we don't require any extra memory barriers after
that.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The premise of commit 6f9f17287e ("SUNRPC: Mitigate cond_resched() in
xprt_transmit()") was that cond_resched() is expensive and unnecessary
when there has been just a single send.
The point of cond_resched() is to ensure that tasks that should pre-empt
this one get a chance to do so when it is safe to do so. The code prior
to commit 6f9f17287e failed to take into account that it was keeping a
rpc_task pinned for longer than it needed to, and so rather than doing a
full revert, let's just move the cond_resched.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
- New Features:
- Better client responsiveness when server isn't replying
- Use refcount_t in sunrpc rpc_client refcount tracking
- Add srcaddr and dst_port to the sunrpc sysfs info files
- Add basic support for connection sharing between servers with multiple NICs`
- Bugfixes and Cleanups:
- Sunrpc tracepoint cleanups
- Disconnect after ib_post_send() errors to avoid deadlocks
- Fix for tearing down rpcrdma_reps
- Fix a potential pNFS layoutget livelock loop
- pNFS layout barrier fixes
- Fix a potential memory corruption in rpc_wake_up_queued_task_set_status()
- Fix reconnection locking
- Fix return value of get_srcport()
- Remove rpcrdma_post_sends()
- Remove pNFS dead code
- Remove copy size restriction for inter-server copies
- Overhaul the NFS callback service
- Clean up sunrpc TCP socket shutdowns
- Always provide aligned buffers to RPC read layers
-----BEGIN PGP SIGNATURE-----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=Ad/3
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-5.15-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client updates from Anna Schumaker:
"New Features:
- Better client responsiveness when server isn't replying
- Use refcount_t in sunrpc rpc_client refcount tracking
- Add srcaddr and dst_port to the sunrpc sysfs info files
- Add basic support for connection sharing between servers with multiple NICs`
Bugfixes and Cleanups:
- Sunrpc tracepoint cleanups
- Disconnect after ib_post_send() errors to avoid deadlocks
- Fix for tearing down rpcrdma_reps
- Fix a potential pNFS layoutget livelock loop
- pNFS layout barrier fixes
- Fix a potential memory corruption in rpc_wake_up_queued_task_set_status()
- Fix reconnection locking
- Fix return value of get_srcport()
- Remove rpcrdma_post_sends()
- Remove pNFS dead code
- Remove copy size restriction for inter-server copies
- Overhaul the NFS callback service
- Clean up sunrpc TCP socket shutdowns
- Always provide aligned buffers to RPC read layers"
* tag 'nfs-for-5.15-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (39 commits)
NFS: Always provide aligned buffers to the RPC read layers
NFSv4.1 add network transport when session trunking is detected
SUNRPC enforce creation of no more than max_connect xprts
NFSv4 introduce max_connect mount options
SUNRPC add xps_nunique_destaddr_xprts to xprt_switch_info in sysfs
SUNRPC keep track of number of transports to unique addresses
NFSv3: Delete duplicate judgement in nfs3_async_handle_jukebox
SUNRPC: Tweak TCP socket shutdown in the RPC client
SUNRPC: Simplify socket shutdown when not reusing TCP ports
NFSv4.2: remove restriction of copy size for inter-server copy.
NFS: Clean up the synopsis of callback process_op()
NFS: Extract the xdr_init_encode/decode() calls from decode_compound
NFS: Remove unused callback void decoder
NFS: Add a private local dispatcher for NFSv4 callback operations
SUNRPC: Eliminate the RQ_AUTHERR flag
SUNRPC: Set rq_auth_stat in the pg_authenticate() callout
SUNRPC: Add svc_rqst::rq_auth_stat
SUNRPC: Add dst_port to the sysfs xprt info file
SUNRPC: Add srcaddr as a file in sysfs
sunrpc: Fix return value of get_srcport()
...
Disconnect injection stress-tests the ability for both client and
server implementations to behave resiliently in the face of network
instability.
Convert the existing client-side disconnect injection infrastructure
to use the kernel's generic error injection facility. The generic
facility has a richer set of injection criteria.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The xprtrdma client code currently relies on the task that initiated the
connect to hold the XPRT_LOCK for the duration of the connection
attempt. If the task is woken early, due to some other event, then that
lock could get released early.
Avoid races by using the same mechanism that the socket code uses of
transferring lock ownership to the RDMA connect worker itself. That
frees us to call rpcrdma_xprt_disconnect() directly since we're now
guaranteed exclusion w.r.t. other callers.
Fixes: 4cf44be6f1 ("xprtrdma: Fix recursion into rpcrdma_xprt_disconnect()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Consolidate duplicated code in xprt_force_disconnect() and
xprt_conditional_disconnect().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
We really should not call rpc_wake_up_queued_task_set_status() with
xprt->snd_task as an argument unless we are certain that is actually an
rpc_task.
Fixes: 0445f92c5d ("SUNRPC: Fix disconnection races")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Allow to query and set the destination's address of a transport.
Setting of the destination address is allowed only for TCP or RDMA
based connections.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This adds a unique identifier for a sunrpc transport in sysfs, which is
similarly managed to the unique IDs of clients.
Signed-off-by: Dan Aloni <dan@kernelim.com>
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Ensure that we fix the XPRT_CONGESTED starvation issue for RDMA as well
as socket based transports.
Ensure we always initialise the request after waking up from the backlog
list.
Fixes: e877a88d1f ("SUNRPC in case of backlog, hand free slots directly to waiting task")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If sunrpc.tcp_max_slot_table_entries is small and there are tasks
on the backlog queue, then when a request completes it is freed and the
first task on the queue is woken. The expectation is that it will wake
and claim that request. However if it was a sync task and the waiting
process was killed at just that moment, it will wake and NOT claim the
request.
As long as TASK_CONGESTED remains set, requests can only be claimed by
tasks woken from the backlog, and they are woken only as requests are
freed, so when a task doesn't claim a request, no other task can ever
get that request until TASK_CONGESTED is cleared. Each time this
happens the number of available requests is decreased by one.
With a sufficiently high workload and sufficiently low setting of
max_slot (16 in the case where this was seen), TASK_CONGESTED can remain
set for an extended period, and the above scenario (of a process being
killed just as its task was woken) can repeat until no requests can be
allocated. Then traffic stops.
This patch addresses the problem by introducing a positive handover of a
request from a completing task to a backlog task - the request is never
freed when there is a backlog.
When a task is woken it might not already have a request attached in
which case it is *not* freed (as with current code) but is initialised
(if needed) and used. If it isn't used it will eventually be freed by
rpc_exit_task(). xprt_release() is enhanced to be able to correctly
release an uninitialised request.
Fixes: ba60eb25ff ("SUNRPC: Fix a livelock problem in the xprt->backlog queue")
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Currently if a major timeout value is reached, but the minor value has
not been reached, an ETIMEOUT will not be sent back to the caller.
This can occur if the v4 server is not responding to requests and
retrans is configured larger than the default of two.
For example, A TCP mount with a configured timeout value of 50 and a
retransmission count of 3 to a v4 server which is not responding:
1. Initial value and increment set to 5s, maxval set to 20s, retries at 3
2. Major timeout is set to 20s, minor timeout set to 5s initially
3. xport_adjust_timeout() is called after 5s, retry with 10s timeout,
minor timeout is bumped to 10s
4. And again after another 10s, 15s total time with minor timeout set
to 15s
5. After 20s total time xport_adjust_timeout is called as major timeout is
reached, but skipped because the minor timeout is not reached
- After this time the cpu spins continually calling
xport_adjust_timeout() and returning 0 for 10 seconds.
As seen on perf sched:
39243.913182 [0005] mount.nfs[3794] 4607.938 0.017 9746.863
6. This continues until the 15s minor timeout condition is reached (in
this case for 10 seconds). After which the ETIMEOUT is processed
back to the caller, the cpu spinning stops, and normal operations
continue
Fixes: 7de62bc09f ("SUNRPC dont update timeout value on connection reset")
Signed-off-by: Chris Dion <Christopher.Dion@dell.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This tracepoint can crash when dereferencing snd_task because
when some transports connect, they put a cookie in that field
instead of a pointer to an rpc_task.
BUG: KASAN: use-after-free in trace_event_raw_event_xprt_writelock_event+0x141/0x18e [sunrpc]
Read of size 2 at addr ffff8881a83bd3a0 by task git/331872
CPU: 11 PID: 331872 Comm: git Tainted: G S 5.12.0-rc2-00007-g3ab6e585a7f9 #1453
Hardware name: Supermicro SYS-6028R-T/X10DRi, BIOS 1.1a 10/16/2015
Call Trace:
dump_stack+0x9c/0xcf
print_address_description.constprop.0+0x18/0x239
kasan_report+0x174/0x1b0
trace_event_raw_event_xprt_writelock_event+0x141/0x18e [sunrpc]
xprt_prepare_transmit+0x8e/0xc1 [sunrpc]
call_transmit+0x4d/0xc6 [sunrpc]
Fixes: 9ce07ae5eb ("SUNRPC: Replace dprintk() call site in xprt_prepare_transmit")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
A separate tracepoint can be left enabled all the time to capture
rare but important retransmission events. So for example:
kworker/u26:3-568 [009] 156.967933: xprt_retransmit: task:44093@5 xid=0xa25dbc79 nfsv3 WRITE ntrans=2
Or, for example, enable all nfs and nfs4 tracepoints, and set up a
trigger to disable tracing when xprt_retransmit fires to capture
everything that leads up to it.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
I've hit some crashes that occur in the xprt_rdma_inject_disconnect
path. It appears that, for some provides, rdma_disconnect() can
take so long that the transport can disconnect and release its
hardware resources while rdma_disconnect() is still running,
resulting in a UAF in the provider.
The transport's fault injection method may depend on the stability
of transport data structures. That means it needs to be invoked
only from contexts that hold the transport write lock.
Fixes: 4a06825839 ("SUNRPC: Transport fault injection")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When we have multiple RPC requests queued up, it makes sense to set the
TCP_CORK option while the transmit queue is non-empty.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
After we've looked up the transport module, we need to ensure it can't
go away until we've finished running the transport setup code.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
According to RFC5666, the correct netid for an IPv6 addressed RDMA
transport is "rdma6", which we've supported as a mount option since
Linux-4.7. The problem is when we try to load the module "xprtrdma6",
that will fail, since there is no modulealias of that name.
Fixes: 181342c5eb ("xprtrdma: Add rdma6 option to support NFS/RDMA IPv6")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The original purpose of this expensive call is to prevent a long
queue of requests from blocking other work.
The cond_resched() call is unnecessary after just a single send
operation.
For longer queues, instead of invoking the kernel scheduler, simply
release the transport send lock and return to the RPC scheduler.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This trace event can be used to audit transport connections from the
client.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Generate a trace event when an RPC request is queued without being
sent immediately.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Replace a dprintk() with a tracepoint. The tracepoint marks the
point where an RPC request is assigned an XID.
Additional clean up: Remove trace_xprt_enq_xmit, which reports much
the same thing. That tracepoint was added for debugging commit
918f3c1fe8 ("SUNRPC: Improve latency for interactive tasks").
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
These instruments don't appear to add any substantial value.
We already have this at the termination of each RPC:
iozone-2617 [002] 975.713126: rpc_stats_latency: task:418@5 xid=0x260eab5d nfsv3 LOOKUP backlog=15 rtt=32 execute=58
iozone-2617 [002] 975.713127: xprt_release_cong: task:418@5 snd_task:4294967295 cong=256 cwnd=16384
iozone-2617 [002] 975.713127: xprt_put_cong: task:418@5 snd_task:4294967295 cong=0 cwnd=16384
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Request completion is already recorded by an "rpc_task_wakeup
queue=xprt_pending" trace record. A subsequent rpc_xdr_recvfrom
trace record shows the number of bytes received.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Current behaviour: every time a v3 operation is re-sent to the server
we update (double) the timeout. There is no distinction between whether
or not the previous timer had expired before the re-sent happened.
Here's the scenario:
1. Client sends a v3 operation
2. Server RST-s the connection (prior to the timeout) (eg., connection
is immediately reset)
3. Client re-sends a v3 operation but the timeout is now 120sec.
As a result, an application sees 2mins pause before a retry in case
server again does not reply.
Instead, this patch proposes to keep track off when the minor timeout
should happen and if it didn't, then don't update the new timeout.
Value is updated based on the previous value to make timeouts
predictable.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Refactor: Hoist create/destroy/disconnect tracepoints out of
xprtrdma and into the generic RPC client. Some benefits include:
- Enable tracing of xprt lifetime events for the socket transport
types
- Expose the different types of disconnect to help run down
issues with lingering connections
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
To help tie the recorded xdr_buf to a particular RPC transaction,
the client side version of this class should display task ID
information and the server side one should show the request's XID.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This class can be used to create trace points in either the RPC
client or RPC server paths. It simply displays the length of each
part of an xdr_buf, which is useful to determine that the transport
and XDR codecs are operating correctly.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
New Features:
- New tracepoints for congestion control and Local Invalidate WRs
Bugfixes and Cleanups:
- Eliminate log noise in call_reserveresult
- Fix unstable connections after a reconnect
- Clean up some code duplication
- Close race between waking a sender and posting a receive
- Fix MR list corruption, and clean up MR usage
- Remove unused rpcrdma_sendctx fields
- Try to avoid DMA mapping pages if it is too costly
- Wake pending tasks if connection fails
- Replace some dprintk()s with tracepoints
-----BEGIN PGP SIGNATURE-----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=Jlak
-----END PGP SIGNATURE-----
Merge tag 'nfs-rdma-for-5.5-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
NFSoRDMA Client Updates for Linux 5.5
New Features:
- New tracepoints for congestion control and Local Invalidate WRs
Bugfixes and Cleanups:
- Eliminate log noise in call_reserveresult
- Fix unstable connections after a reconnect
- Clean up some code duplication
- Close race between waking a sender and posting a receive
- Fix MR list corruption, and clean up MR usage
- Remove unused rpcrdma_sendctx fields
- Try to avoid DMA mapping pages if it is too costly
- Wake pending tasks if connection fails
- Replace some dprintk()s with tracepoints
When we're destroying the host transport mechanism, we should ensure
that we do not leak memory by failing to release any back channel
slots that might still exist.
Reported-by: Neil Brown <neilb@suse.de>
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
To help debug problems with RPC/RDMA credit management, replace
dprintk() call sites in the transport send lock paths with trace
events.
Similar trace points are defined for the non-congestion paths.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Stable bugfixes:
- Dequeue the request from the receive queue while we're re-encoding # v4.20+
- Fix buffer handling of GSS MIC without slack # 5.1
Features:
- Increase xprtrdma maximum transport header and slot table sizes
- Add support for nfs4_call_sync() calls using a custom rpc_task_struct
- Optimize the default readahead size
- Enable pNFS filelayout LAYOUTGET on OPEN
Other bugfixes and cleanups:
- Fix possible null-pointer dereferences and memory leaks
- Various NFS over RDMA cleanups
- Various NFS over RDMA comment updates
- Don't receive TCP data into a reset request buffer
- Don't try to parse incomplete RPC messages
- Fix congestion window race with disconnect
- Clean up pNFS return-on-close error handling
- Fixes for NFS4ERR_OLD_STATEID handling
-----BEGIN PGP SIGNATURE-----
iQIzBAABCAAdFiEEnZ5MQTpR7cLU7KEp18tUv7ClQOsFAl2NC04ACgkQ18tUv7Cl
QOs4Tg//bAlGs+dIKixAmeMKmTd6I34laUnuyV/12yPQDgo6bryLrTngfe2BYvmG
2l+8H7yHfR4/gQE4vhR0c15xFgu6pvjBGR0/nNRaXienIPXO4xsQkcaxVA7SFRY2
HjffZwyoBfjyRps0jL+2sTsKbRtSkf9Dn+BONRgesg51jK1jyWkXqXpmgi4uMO4i
ojpTrW81dwo7Yhv08U2A/Q1ifMJ8F9dVYuL5sm+fEbVI/Nxoz766qyB8rs8+b4Xj
3gkfyh/Y1zoMmu6c+r2Q67rhj9WYbDKpa6HH9yX1zM/RLTiU7czMX+kjuQuOHWxY
YiEk73NjJ48WJEep3odess1q/6WiAXX7UiJM1SnDFgAa9NZMdfhqMm6XduNO1m60
sy0i8AdxdQciWYexOXMsBuDUCzlcoj4WYs1QGpY3uqO1MznQS/QUfu65fx8CzaT5
snm6ki5ivqXH/js/0Z4MX2n/sd1PGJ5ynMkekxJ8G3gw+GC/oeSeGNawfedifLKK
OdzyDdeiel5Me1p4I28j1WYVLHvtFmEWEU9oytdG0D/rjC/pgYgW/NYvAao8lQ4Z
06wdcyAM66ViAPrbYeE7Bx4jy8zYRkiw6Y3kIbLgrlMugu3BhIW5Mi3BsgL4f4am
KsqkzUqPZMCOVwDuUILSuPp4uHaR+JTJttywiLniTL6reF5kTiA=
=4Ey6
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-5.4-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client updates from Anna Schumaker:
"Stable bugfixes:
- Dequeue the request from the receive queue while we're re-encoding
# v4.20+
- Fix buffer handling of GSS MIC without slack # 5.1
Features:
- Increase xprtrdma maximum transport header and slot table sizes
- Add support for nfs4_call_sync() calls using a custom
rpc_task_struct
- Optimize the default readahead size
- Enable pNFS filelayout LAYOUTGET on OPEN
Other bugfixes and cleanups:
- Fix possible null-pointer dereferences and memory leaks
- Various NFS over RDMA cleanups
- Various NFS over RDMA comment updates
- Don't receive TCP data into a reset request buffer
- Don't try to parse incomplete RPC messages
- Fix congestion window race with disconnect
- Clean up pNFS return-on-close error handling
- Fixes for NFS4ERR_OLD_STATEID handling"
* tag 'nfs-for-5.4-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (53 commits)
pNFS/filelayout: enable LAYOUTGET on OPEN
NFS: Optimise the default readahead size
NFSv4: Handle NFS4ERR_OLD_STATEID in LOCKU
NFSv4: Handle NFS4ERR_OLD_STATEID in CLOSE/OPEN_DOWNGRADE
NFSv4: Fix OPEN_DOWNGRADE error handling
pNFS: Handle NFS4ERR_OLD_STATEID on layoutreturn by bumping the state seqid
NFSv4: Add a helper to increment stateid seqids
NFSv4: Handle RPC level errors in LAYOUTRETURN
NFSv4: Handle NFS4ERR_DELAY correctly in return-on-close
NFSv4: Clean up pNFS return-on-close error handling
pNFS: Ensure we do clear the return-on-close layout stateid on fatal errors
NFS: remove unused check for negative dentry
NFSv3: use nfs_add_or_obtain() to create and reference inodes
NFS: Refactor nfs_instantiate() for dentry referencing callers
SUNRPC: Fix congestion window race with disconnect
SUNRPC: Don't try to parse incomplete RPC messages
SUNRPC: Rename xdr_buf_read_netobj to xdr_buf_read_mic
SUNRPC: Fix buffer handling of GSS MIC without slack
SUNRPC: RPC level errors should always set task->tk_rpc_status
SUNRPC: Don't receive TCP data into a request buffer that has been reset
...
If the congestion window closes just as the transport disconnects,
a reconnect is never driven because:
1. The XPRT_CONG_WAIT flag prevents tasks from taking the write lock
2. There's no wake-up of the first task on the xprt->sending queue
To address this, clear the congestion wait flag as part of
completing a disconnect.
Fixes: 75891f502f ("SUNRPC: Support for congestion control ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Ensure that we dequeue the request from the transport receive queue
while we're re-encoding to prevent issues like use-after-free when
we release the bvec.
Fixes: 7536908982 ("SUNRPC: Ensure the bvecs are reset when we re-encode...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
