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2020-11-11xprtrdma: Trace unmap_sync callsChuck Lever
->buf_free is called nearly once per RPC. Only rarely does xprt_rdma_free() have to do anything, thus tracing every one of these calls seems unnecessary. Instead, just throw a trace event when that one occasional RPC still has MRs that need to be released. xprt_rdma_free() is further micro-optimized to reduce the amount of work done in the common case. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11xprtrdma: Display the task ID when reporting MR eventsChuck Lever
Tie each MR event to the requesting rpc_task to make it easier to follow MR ownership and control flow. MR unmapping and recycling can happen in the background, after an MR's mr_req field is stale, so set up a separate tracepoint class for those events. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11xprtrdma: Clean up trace_xprtrdma_nomrs()Chuck Lever
- Rename it following the "_err" suffix convention - Replace display of kernel memory addresses - Tie MR exhaustion to a peer IP address, similar to the createmrs tracepoint Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11xprtrdma: Clean up xprtrdma callback tracepointsChuck Lever
- Replace displayed kernel memory addresses - Tie the XID and event with the peer's IP address Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11xprtrdma: Clean up tracepoints in the reply pathChuck Lever
Replace unnecessary display of kernel memory addresses. Also, there are no longer any trace_xprtrdma_defer_cmp() call sites. And remove the trace_xprtrdma_leaked_rep() tracepoint because there doesn't seem to be an overwhelming need to have a tracepoint for catching a software bug that has long since been fixed. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11xprtrdma: Clean up reply parsing error tracepointsChuck Lever
- Rename the tracepoints with the "_err" suffix to indicate these are rare error events - Replace display of kernel memory addresses - Tie the XID and error to a connection IP address instead Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11xprtrdma: Clean up trace_xprtrdma_post_linvChuck Lever
- Replace the display of kernel memory addresses - Add "_err" to the end of its name to indicate that it's a tracepoint that fires only when there's an error Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11xprtrdma: Introduce FRWR completion IDsChuck Lever
Set up a completion ID in each rpcrdma_frwr. The ID is used to match an incoming completion to a transport (CQ) and other MR-related activity. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11xprtrdma: Introduce Send completion IDsChuck Lever
Set up a completion ID in each rpcrdma_req. The ID is used to match an incoming Send completion to a transport and to a previous ib_post_send(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11xprtrdma: Introduce Receive completion IDsChuck Lever
Set up a completion ID in each rpcrdma_rep. The ID is used to match an incoming Receive completion to a transport and to a previous ib_post_recv(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-11xprtrdma: Replace dprintk call sites in ERR_CHUNK pathChuck Lever
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-10-22Merge tag 'nfsd-5.10' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd updates from Bruce Fields: "The one new feature this time, from Anna Schumaker, is READ_PLUS, which has the same arguments as READ but allows the server to return an array of data and hole extents. Otherwise it's a lot of cleanup and bugfixes" * tag 'nfsd-5.10' of git://linux-nfs.org/~bfields/linux: (43 commits) NFSv4.2: Fix NFS4ERR_STALE error when doing inter server copy SUNRPC: fix copying of multiple pages in gss_read_proxy_verf() sunrpc: raise kernel RPC channel buffer size svcrdma: fix bounce buffers for unaligned offsets and multiple pages nfsd: remove unneeded break net/sunrpc: Fix return value for sysctl sunrpc.transports NFSD: Encode a full READ_PLUS reply NFSD: Return both a hole and a data segment NFSD: Add READ_PLUS hole segment encoding NFSD: Add READ_PLUS data support NFSD: Hoist status code encoding into XDR encoder functions NFSD: Map nfserr_wrongsec outside of nfsd_dispatch NFSD: Remove the RETURN_STATUS() macro NFSD: Call NFSv2 encoders on error returns NFSD: Fix .pc_release method for NFSv2 NFSD: Remove vestigial typedefs NFSD: Refactor nfsd_dispatch() error paths NFSD: Clean up nfsd_dispatch() variables NFSD: Clean up stale comments in nfsd_dispatch() NFSD: Clean up switch statement in nfsd_dispatch() ...
2020-10-16svcrdma: fix bounce buffers for unaligned offsets and multiple pagesDan Aloni
This was discovered using O_DIRECT at the client side, with small unaligned file offsets or IOs that span multiple file pages. Fixes: e248aa7be86 ("svcrdma: Remove max_sge check at connect time") Signed-off-by: Dan Aloni <dan@kernelim.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-09-25net: sunrpc: delete repeated wordsRandy Dunlap
Drop duplicate words in net/sunrpc/. Also fix "Anyone" to be "Any one". Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: linux-nfs@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-09-21xprtrdma: drop double zeroingJulia Lawall
sg_init_table zeroes its first argument, so the allocation of that argument doesn't have to. the semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression x,n,flags; @@ x = - kcalloc + kmalloc_array (n,sizeof(*x),flags) ... sg_init_table(x,n) // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Acked-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-09-21SUNRPC: Hoist trace_xprtrdma_op_setport into generic codeChuck Lever
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-09-21SUNRPC: Remove debugging instrumentation from xprt_releaseChuck Lever
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>
2020-09-21SUNRPC: Hoist trace_xprtrdma_op_allocate into generic codeChuck Lever
Introduce a tracepoint in call_allocate that reports the exact sizes in the RPC buffer allocation request and the status of the result. This helps catch problems with XDR buffer provisioning, and replaces transport-specific debugging instrumentation. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-09-09Merge tag 'nfs-for-5.9-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Pull NFS client bugfixes from Trond Myklebust: - Fix an NFS/RDMA resource leak - Fix the error handling during delegation recall - NFSv4.0 needs to return the delegation on a zero-stateid SETATTR - Stop printk reading past end of string * tag 'nfs-for-5.9-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: SUNRPC: stop printk reading past end of string NFS: Zero-stateid SETATTR should first return delegation NFSv4.1 handle ERR_DELAY error reclaiming locking state on delegation recall xprtrdma: Release in-flight MRs on disconnect
2020-08-26xprtrdma: Release in-flight MRs on disconnectChuck Lever
Dan Aloni reports that when a server disconnects abruptly, a few memory regions are left DMA mapped. Over time this leak could pin enough I/O resources to slow or even deadlock an NFS/RDMA client. I found that if a transport disconnects before pending Send and FastReg WRs can be posted, the to-be-registered MRs are stranded on the req's rl_registered list and never released -- since they weren't posted, there's no Send completion to DMA unmap them. Reported-by: Dan Aloni <dan@kernelim.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-08-23treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-09Merge tag 'nfsd-5.9' of git://git.linux-nfs.org/projects/cel/cel-2.6Linus Torvalds
Pull NFS server updates from Chuck Lever: "Highlights: - Support for user extended attributes on NFS (RFC 8276) - Further reduce unnecessary NFSv4 delegation recalls Notable fixes: - Fix recent krb5p regression - Address a few resource leaks and a rare NULL dereference Other: - De-duplicate RPC/RDMA error handling and other utility functions - Replace storage and display of kernel memory addresses by tracepoints" * tag 'nfsd-5.9' of git://git.linux-nfs.org/projects/cel/cel-2.6: (38 commits) svcrdma: CM event handler clean up svcrdma: Remove transport reference counting svcrdma: Fix another Receive buffer leak SUNRPC: Refresh the show_rqstp_flags() macro nfsd: netns.h: delete a duplicated word SUNRPC: Fix ("SUNRPC: Add "@len" parameter to gss_unwrap()") nfsd: avoid a NULL dereference in __cld_pipe_upcall() nfsd4: a client's own opens needn't prevent delegations nfsd: Use seq_putc() in two functions svcrdma: Display chunk completion ID when posting a rw_ctxt svcrdma: Record send_ctxt completion ID in trace_svcrdma_post_send() svcrdma: Introduce Send completion IDs svcrdma: Record Receive completion ID in svc_rdma_decode_rqst svcrdma: Introduce Receive completion IDs svcrdma: Introduce infrastructure to support completion IDs svcrdma: Add common XDR encoders for RDMA and Read segments svcrdma: Add common XDR decoders for RDMA and Read segments SUNRPC: Add helpers for decoding list discriminators symbolically svcrdma: Remove declarations for functions long removed svcrdma: Clean up trace_svcrdma_send_failed() tracepoint ...
2020-07-28svcrdma: CM event handler clean upChuck Lever
Now that there's a core tracepoint that reports these events, there's no need to maintain dprintk() call sites in each arm of the switch statements. We also refresh the documenting comments. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-28svcrdma: Remove transport reference countingChuck Lever
Jason tells me that a ULP cannot rely on getting an ESTABLISHED and DISCONNECTED event pair for each connection, so transport reference counting in the CM event handler will never be reliable. Now that we have ib_drain_qp(), svcrdma should no longer need to hold transport references while Sends and Receives are posted. So remove the get/put call sites in the CM event handlers. This eliminates a significant source of locked memory bus traffic. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-28svcrdma: Fix another Receive buffer leakChuck Lever
During a connection tear down, the Receive queue is flushed before the device resources are freed. Typically, all the Receives flush with IB_WR_FLUSH_ERR. However, any pending successful Receives flush with IB_WR_SUCCESS, and the server automatically posts a fresh Receive to replace the completing one. This happens even after the connection has closed and the RQ is drained. Receives that are posted after the RQ is drained appear never to complete, causing a Receive resource leak. The leaked Receive buffer is left DMA-mapped. To prevent these late-posted recv_ctxt's from leaking, block new Receive posting after XPT_CLOSE is set. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-15xprtrdma: fix incorrect header size calculationsColin Ian King
Currently the header size calculations are using an assignment operator instead of a += operator when accumulating the header size leading to incorrect sizes. Fix this by using the correct operator. Addresses-Coverity: ("Unused value") Fixes: 302d3deb2068 ("xprtrdma: Prevent inline overflow") Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-07-13svcrdma: Display chunk completion ID when posting a rw_ctxtChuck Lever
Re-use the post_rw tracepoint (safely) to trace cc_info lifetime events, including completion IDs. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Record send_ctxt completion ID in trace_svcrdma_post_send()Chuck Lever
First, refactor: Dereference the svc_rdma_send_ctxt inside svc_rdma_send() instead of at every call site. Then, it can be passed into trace_svcrdma_post_send() to get the proper completion ID. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Introduce Send completion IDsChuck Lever
Set up a completion ID in each svc_rdma_send_ctxt. The ID is used to match an incoming Send completion to a transport and to a previous ib_post_send(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Record Receive completion ID in svc_rdma_decode_rqstChuck Lever
When recording a trace event in the Receive path, tie decoding results and errors to an incoming Receive completion. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Introduce Receive completion IDsChuck Lever
Set up a completion ID in each svc_rdma_recv_ctxt. The ID is used to match an incoming Receive completion to a transport and to a previous ib_post_recv(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Add common XDR encoders for RDMA and Read segmentsChuck Lever
Clean up: De-duplicate some code. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Add common XDR decoders for RDMA and Read segmentsChuck Lever
Clean up: De-duplicate some code. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13SUNRPC: Add helpers for decoding list discriminators symbolicallyChuck Lever
Use these helpers in a few spots to demonstrate their use. The remaining open-coded discriminator checks in rpcrdma will be addressed in subsequent patches. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Clean up trace_svcrdma_send_failed() tracepointChuck Lever
- Use the _err naming convention instead - Remove display of kernel memory address of the controlling xprt Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Consolidate send_error helper functionsChuck Lever
Final refactor: Replace internals of svc_rdma_send_error() with a simple call to svc_rdma_send_error_msg(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Make svc_rdma_send_error_msg() a global functionChuck Lever
Prepare for svc_rdma_send_error_msg() to be invoked from another source file. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Eliminate return value for svc_rdma_send_error_msg()Chuck Lever
Like svc_rdma_send_error(), have svc_rdma_send_error_msg() handle any error conditions internally, rather than duplicating that recovery logic at every call site. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Add a @status parameter to svc_rdma_send_error_msg()Chuck Lever
The common "send RDMA_ERR" function should be in svc_rdma_sendto.c, since that is where the other Send-related functions are located. So from here, I will beef up svc_rdma_send_error_msg() and deprecate svc_rdma_send_error(). A generic svc_rdma_send_error_msg() will need to handle both ERR_CHUNK and ERR_VERS. Copy that logic from svc_rdma_send_error() to svc_rdma_send_error_msg(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Add @rctxt parameter to svc_rdma_send_error() functionsChuck Lever
Another step towards making svc_rdma_send_error_msg() and svc_rdma_send_error() similar enough to eliminate one of them. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Remove save_io_pages() call from send_error_msg()Chuck Lever
Commit 4757d90b15d8 ("svcrdma: Report Write/Reply chunk overruns") made an effort to preserve I/O pages until RDMA Write completion. In a subsequent patch, I intend to de-duplicate the two functions that send ERR_CHUNK responses. Pull the save_io_pages() call out of svc_rdma_send_error_msg() to make it more like svc_rdma_send_error(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13svcrdma: Fix page leak in svc_rdma_recv_read_chunk()Chuck Lever
Commit 07d0ff3b0cd2 ("svcrdma: Clean up Read chunk path") moved the page saver logic so that it gets executed event when an error occurs. In that case, the I/O is never posted, and those pages are then leaked. Errors in this path, however, are quite rare. Fixes: 07d0ff3b0cd2 ("svcrdma: Clean up Read chunk path") Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13xprtrdma: Fix handling of connect errorsChuck Lever
Ensure that the connect worker is awoken if an attempt to establish a connection is unsuccessful. Otherwise the worker waits forever and the transport workload hangs. Connect errors should not attempt to destroy the ep, since the connect worker continues to use it after the handler runs, so these errors are now handled independently of DISCONNECTED events. Reported-by: Dan Aloni <dan@kernelim.com> Fixes: e28ce90083f0 ("xprtrdma: kmalloc rpcrdma_ep separate from rpcrdma_xprt") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-07-13xprtrdma: Fix return code from rpcrdma_xprt_connect()Chuck Lever
I noticed that when rpcrdma_xprt_connect() returns -ENOMEM, instead of retrying the connect, the RPC client kills the RPC task that requested the connection. We want a retry here. Fixes: cb586decbb88 ("xprtrdma: Make sendctx queue lifetime the same as connection lifetime") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-07-13xprtrdma: Fix recursion into rpcrdma_xprt_disconnect()Chuck Lever
Both Dan and I have observed two processes invoking rpcrdma_xprt_disconnect() concurrently. In my case: 1. The connect worker invokes rpcrdma_xprt_disconnect(), which drains the QP and waits for the final completion 2. This causes the newly posted Receive to flush and invoke xprt_force_disconnect() 3. xprt_force_disconnect() sets CLOSE_WAIT and wakes up the RPC task that is holding the transport lock 4. The RPC task invokes xprt_connect(), which calls ->ops->close 5. xprt_rdma_close() invokes rpcrdma_xprt_disconnect(), which tries to destroy the QP. Deadlock. To prevent xprt_force_disconnect() from waking anything, handle the clean up after a failed connection attempt in the xprt's sndtask. The retry loop is removed from rpcrdma_xprt_connect() to ensure that the newly allocated ep and id are properly released before a REJECTED connection attempt can be retried. Reported-by: Dan Aloni <dan@kernelim.com> Fixes: e28ce90083f0 ("xprtrdma: kmalloc rpcrdma_ep separate from rpcrdma_xprt") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-07-13xprtrdma: Fix double-free in rpcrdma_ep_create()Chuck Lever
In the error paths, there's no need to call kfree(ep) after calling rpcrdma_ep_put(ep). Fixes: e28ce90083f0 ("xprtrdma: kmalloc rpcrdma_ep separate from rpcrdma_xprt") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-06-22xprtrdma: Fix handling of RDMA_ERROR repliesChuck Lever
The RPC client currently doesn't handle ERR_CHUNK replies correctly. rpcrdma_complete_rqst() incorrectly passes a negative number to xprt_complete_rqst() as the number of bytes copied. Instead, set task->tk_status to the error value, and return zero bytes copied. In these cases, return -EIO rather than -EREMOTEIO. The RPC client's finite state machine doesn't know what to do with -EREMOTEIO. Additional clean ups: - Don't double-count RDMA_ERROR replies - Remove a stale comment Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: <stable@kernel.vger.org> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-06-22xprtrdma: Clean up disconnectChuck Lever
1. Ensure that only rpcrdma_cm_event_handler() modifies ep->re_connect_status to avoid racy changes to that field. 2. Ensure that xprt_force_disconnect() is invoked only once as a transport is closed or destroyed. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-06-22xprtrdma: Clean up synopsis of rpcrdma_flush_disconnect()Chuck Lever
Refactor: Pass struct rpcrdma_xprt instead of an IB layer object. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-06-22xprtrdma: Use re_connect_status safely in rpcrdma_xprt_connect()Chuck Lever
Clean up: Sometimes creating a fresh rpcrdma_ep can fail. That's why xprt_rdma_connect() always checks if the r_xprt->rx_ep pointer is valid before dereferencing it. Instead, xprt_rdma_connect() can simply check rpcrdma_xprt_connect()'s return value. Also, there's no need to set re_connect_status to zero just after the rpcrdma_ep is created, since it is allocated with kzalloc. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
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