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2020-06-11SUNRPC: Trace transport lifetime eventsChuck Lever1-10/+11
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>
2020-06-11SUNRPC: Split the xdr_buf event classChuck Lever1-1/+1
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>
2020-03-16svcrdma: Create a generic tracing class for displaying xdr_buf layoutChuck Lever1-2/+1
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>
2019-11-18Merge tag 'nfs-rdma-for-5.5-1' of git://git.linux-nfs.org/projects/anna/linux-nfsTrond Myklebust1-9/+13
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
2019-10-30SUNRPC: Destroy the back channel when we destroy the host transportTrond Myklebust1-0/+5
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>
2019-10-24SUNRPC: Add trace points to observe transport congestion controlChuck Lever1-9/+13
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>
2019-09-26Merge tag 'nfs-for-5.4-1' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds1-23/+38
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 ...
2019-09-20SUNRPC: Fix congestion window race with disconnectChuck Lever1-0/+7
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: 75891f502f5f ("SUNRPC: Support for congestion control ... ") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-09-17SUNRPC: Dequeue the request from the receive queue while we're re-encodingTrond Myklebust1-23/+31
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: 7536908982047 ("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>
2019-08-26Revert "NFSv4/flexfiles: Abort I/O early if the layout segment was invalidated"Trond Myklebust1-7/+0
This reverts commit a79f194aa4879e9baad118c3f8bb2ca24dbef765. The mechanism for aborting I/O is racy, since we are not guaranteed that the request is asleep while we're changing both task->tk_status and task->tk_action. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: stable@vger.kernel.org # v5.1
2019-07-18SUNRPC: Ensure the bvecs are reset when we re-encode the RPC requestTrond Myklebust1-0/+2
The bvec tracks the list of pages, so if the number of pages changes due to a re-encode, we need to reset the bvec as well. Fixes: 277e4ab7d530 ("SUNRPC: Simplify TCP receive code by switching...") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: stable@vger.kernel.org # v4.20+
2019-07-12Merge tag 'nfs-rdma-for-5.3-1' of git://git.linux-nfs.org/projects/anna/linux-nfsTrond Myklebust1-0/+32
NFSoRDMA client updates for 5.3 New features: - Add a way to place MRs back on the free list - Reduce context switching - Add new trace events Bugfixes and cleanups: - Fix a BUG when tracing is enabled with NFSv4.1 - Fix a use-after-free in rpcrdma_post_recvs - Replace use of xdr_stream_pos in rpcrdma_marshal_req - Fix occasional transport deadlock - Fix show_nfs_errors macros, other tracing improvements - Remove RPCRDMA_REQ_F_PENDING and fr_state - Various simplifications and refactors
2019-07-09xprtrdma: Modernize ops->connectChuck Lever1-0/+32
Adapt and apply changes that were made to the TCP socket connect code. See the following commits for details on the purpose of these changes: Commit 7196dbb02ea0 ("SUNRPC: Allow changing of the TCP timeout parameters on the fly") Commit 3851f1cdb2b8 ("SUNRPC: Limit the reconnect backoff timer to the max RPC message timeout") Commit 02910177aede ("SUNRPC: Fix reconnection timeouts") Some common transport code is moved to xprt.c to satisfy the code duplication police. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-07-06SUNRPC: Fix possible autodisconnect during connect due to old last_usedDave Wysochanski1-1/+1
Ensure last_used is updated before calling mod_timer inside xprt_schedule_autodisconnect. This avoids a possible xprt_autoclose firing immediately after a successful connect when xprt_unlock_connect calls xprt_schedule_autodisconnect with an old value of last_used. Signed-off-by: Dave Wysochanski <dwysocha@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-07-06Merge branch 'bh-remove'Trond Myklebust1-33/+28
2019-07-06SUNRPC: Move call to rpc_count_iostats before rpc_call_doneDave Wysochanski1-4/+0
For diagnostic purposes, it would be useful to have an rpc_iostats metric of RPCs completing with tk_status < 0. Unfortunately, tk_status is reset inside the rpc_call_done functions for each operation, and the call to tally the per-op metrics comes after rpc_call_done. Refactor the call to rpc_count_iostat earlier in rpc_exit_task so we can count these RPCs completing in error. Signed-off-by: Dave Wysochanski <dwysocha@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-07-06SUNRPC: Remove the bh-safe lock requirement on xprt->transport_lockTrond Myklebust1-33/+28
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-06-21Revert "SUNRPC: Declare RPC timers as TIMER_DEFERRABLE"Anna Schumaker1-3/+1
Jon Hunter reports: "I have been noticing intermittent failures with a system suspend test on some of our machines that have a NFS mounted root file-system. Bisecting this issue points to your commit 431235818bc3 ("SUNRPC: Declare RPC timers as TIMER_DEFERRABLE") and reverting this on top of v5.2-rc3 does appear to resolve the problem. The cause of the suspend failure appears to be a long delay observed sometimes when resuming from suspend, and this is causing our test to timeout." This reverts commit 431235818bc3a919ca7487500c67c3144feece80. Reported-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-05-21treewide: Add SPDX license identifier for missed filesThomas Gleixner1-0/+1
Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25SUNRPC: Update comments based on recent changesChuck Lever1-2/+2
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25SUNRPC: Start the first major timeout calculation at task creationTrond Myklebust1-10/+34
When calculating the major timeout for a new task, when we know that the connection has been broken, use the task->tk_start to ensure that we also take into account the time spent waiting for a slot or session slot. This ensures that we fail over soft requests relatively quickly once the connection has actually been broken, and the first requests have started to fail. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25SUNRPC: Ensure that the transport layer respect major timeoutsTrond Myklebust1-4/+13
Ensure that when in the transport layer, we don't sleep past a major timeout. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25SUNRPC: Declare RPC timers as TIMER_DEFERRABLETrond Myklebust1-1/+3
Don't wake idle CPUs only for the purpose of servicing an RPC queue timeout. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25SUNRPC: Add function rpc_sleep_on_timeout()Trond Myklebust1-15/+21
Clean up the RPC task sleep interfaces by replacing the task->tk_timeout 'hidden parameter' to rpc_sleep_on() with a new function that takes an absolute timeout. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25SUNRPC: Refactor xprt_request_wait_receive()Trond Myklebust1-37/+42
Convert the transport callback to actually put the request to sleep instead of just setting a timeout. This is in preparation for rpc_sleep_on_timeout(). Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25SUNRPC: Fix up task signallingTrond Myklebust1-0/+4
The RPC_TASK_KILLED flag should really not be set from another context because it can clobber data in the struct task when task->tk_flags is changed non-atomically. Let's therefore swap out RPC_TASK_KILLED with an atomic flag, and add a function to set that flag and safely wake up the task. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-03-15SUNRPC: Use the ENOTCONN error on socket disconnectTrond Myklebust1-1/+1
When the socket is closed, we currently send an EAGAIN error to all pending requests in order to ask them to retransmit. Use ENOTCONN instead, to ensure that they try to reconnect before attempting to transmit. This also helps SOFTCONN tasks to behave correctly in this situation. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-03-01NFSv4/flexfiles: Abort I/O early if the layout segment was invalidatedTrond Myklebust1-0/+7
If a layout segment gets invalidated while a pNFS I/O operation is queued for transmission, then we ideally want to abort immediately. This is particularly the case when there is a large number of I/O related RPCs queued in the RPC layer, and the layout segment gets invalidated due to an ENOSPC error, or an EACCES (because the client was fenced). We may end up forced to spam the MDS with a lot of otherwise unnecessary LAYOUTERRORs after that I/O fails. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-02-25Merge tag 'nfs-rdma-for-5.1-1' of git://git.linux-nfs.org/projects/anna/linux-nfsTrond Myklebust1-4/+6
NFSoRDMA client updates for 5.1 New features: - Convert rpc auth layer to use xdr_streams - Config option to disable insecure enctypes - Reduce size of RPC receive buffers Bugfixes and cleanups: - Fix sparse warnings - Check inline size before providing a write chunk - Reduce the receive doorbell rate - Various tracepoint improvements [Trond: Fix up merge conflicts] Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-02-20SUNRPC: Convert socket page send code to use iov_iter()Trond Myklebust1-0/+1
Simplify the page send code using iov_iter and bvecs. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-02-20SUNRPC: Ensure rq_bytes_sent is reset before request transmissionTrond Myklebust1-2/+0
When we resend a request, ensure that the 'rq_bytes_sent' is reset to zero. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-02-20SUNRPC: Set memalloc_nofs_save() on all rpciod/xprtiod jobsTrond Myklebust1-0/+3
Set memalloc_nofs_save() on all the rpciod/xprtiod jobs so that we ensure memory allocations for asynchronous rpc calls don't ever end up recursing back to the NFS layer for memory reclaim. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-02-14SUNRPC: Introduce trace points in rpc_auth_gss.koChuck Lever1-4/+6
Add infrastructure for trace points in the RPC_AUTH_GSS kernel module, and add a few sample trace points. These report exceptional or unexpected events, and observe the assignment of GSS sequence numbers. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-01-15SUNRPC: Address Kerberos performance/behavior regressionChuck Lever1-1/+1
When using Kerberos with v4.20, I've observed frequent connection loss on heavy workloads. I traced it down to the client underrunning the GSS sequence number window -- NFS servers are required to drop the RPC with the low sequence number, and also drop the connection to signal that an RPC was dropped. Bisected to commit 918f3c1fe83c ("SUNRPC: Improve latency for interactive tasks"). I've got a one-line workaround for this issue, which is easy to backport to v4.20 while a more permanent solution is being derived. Essentially, tk_owner-based sorting is disabled for RPCs that carry a GSS sequence number. Fixes: 918f3c1fe83c ("SUNRPC: Improve latency for interactive ... ") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-01-15SUNRPC: Ensure rq_bytes_sent is reset before request transmissionTrond Myklebust1-0/+1
When we resend a request, ensure that the 'rq_bytes_sent' is reset to zero. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-12-18SUNRPC: Remove xprt_connect_status()Trond Myklebust1-31/+1
Over the years, xprt_connect_status() has been superseded by call_connect_status(), which now handles all the errors that xprt_connect_status() does and more. Since the latter converts all errors that it doesn't recognise to EIO, then it is time for it to be retired. Reported-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Tested-by: Chuck Lever <chuck.lever@oracle.com>
2018-12-18SUNRPC: Fix disconnection racesTrond Myklebust1-1/+4
When the socket is closed, we need to call xprt_disconnect_done() in order to clean up the XPRT_WRITE_SPACE flag, and wake up the sleeping tasks. However, we also want to ensure that we don't wake them up before the socket is closed, since that would cause thundering herd issues with everyone piling up to retransmit before the TCP shutdown dance has completed. Only the task that holds XPRT_LOCKED needs to wake up early in order to allow the close to complete. Reported-by: Dave Wysochanski <dwysocha@redhat.com> Reported-by: Scott Mayhew <smayhew@redhat.com> Cc: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Tested-by: Chuck Lever <chuck.lever@oracle.com>
2018-12-02SUNRPC: Fix a potential race in xprt_connect()Trond Myklebust1-2/+9
If an asynchronous connection attempt completes while another task is in xprt_connect(), then the call to rpc_sleep_on() could end up racing with the call to xprt_wake_pending_tasks(). So add a second test of the connection state after we've put the task to sleep and set the XPRT_CONNECTING flag, when we know that there can be no asynchronous connection attempts still in progress. Fixes: 0b9e79431377d ("SUNRPC: Move the test for XPRT_CONNECTING into...") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-12-02SUNRPC: Fix a memory leak in call_encode()Trond Myklebust1-0/+2
If we retransmit an RPC request, we currently end up clobbering the value of req->rq_rcv_buf.bvec that was allocated by the initial call to xprt_request_prepare(req). Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-10-18Merge tag 'nfs-rdma-for-4.20-1' of git://git.linux-nfs.org/projects/anna/linux-nfsTrond Myklebust1-10/+4
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>
2018-10-02sunrpc: Fix connect metricsChuck Lever1-10/+4
For TCP, the logic in xprt_connect_status is currently never invoked to record a successful connection. Commit 2a4919919a97 ("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>
2018-09-30SUNRPC: Add a bvec array to struct xdr_buf for use with iovec_iter()Trond Myklebust1-0/+17
Add a bvec array to struct xdr_buf, and have the client allocate it when we need to receive data into pages. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30SUNRPC: Convert the xprt->sending queue back to an ordinary wait queueTrond Myklebust1-17/+3
We no longer need priority semantics on the xprt->sending queue, because the order in which tasks are sent is now dictated by their position in the send queue. Note that the backlog queue remains a priority queue, meaning that slot resources are still managed in order of task priority. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30SUNRPC: Convert xprt receive queue to use an rbtreeTrond Myklebust1-11/+82
If the server is slow, we can find ourselves with quite a lot of entries on the receive queue. Converting the search from an O(n) to O(log(n)) can make a significant difference, particularly since we have to hold a number of locks while searching. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30SUNRPC: Don't take transport->lock unnecessarily when taking XPRT_LOCKTrond Myklebust1-2/+5
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30SUNRPC: Cleanup: remove the unused 'task' argument from the request_send()Trond Myklebust1-1/+1
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30SUNRPC: Clean up transport write space handlingTrond Myklebust1-30/+47
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>
2018-09-30SUNRPC: Turn off throttling of RPC slots for TCP socketsTrond Myklebust1-14/+0
The theory was that we would need to grab the socket lock anyway, so we might as well use it to gate the allocation of RPC slots for a TCP socket. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30SUNRPC: Allow soft RPC calls to time out when waiting for the XPRT_LOCKTrond Myklebust1-2/+2
This no longer causes them to lose their place in the transmission queue. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30SUNRPC: Allow calls to xprt_transmit() to drain the entire transmit queueTrond Myklebust1-11/+60
Rather than forcing each and every RPC task to grab the socket write lock in order to send itself, we allow whichever task is holding the write lock to attempt to drain the entire transmit queue. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
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