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path: root/net/sunrpc/xprtrdma/svc_rdma_sendto.c
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2021-08-17svcrdma: Relieve contention on sc_send_lock.Chuck Lever
/proc/lock_stat indicates the the sc_send_lock is heavily contended when the server is under load from a single client. To address this, convert the send_ctxt free list to an llist. Returning an item to the send_ctxt cache is now waitless, which reduces the instruction path length in the single-threaded Send handler (svc_rdma_wc_send). The goal is to enable the ib_comp_wq worker to handle a higher RPC/RDMA Send completion rate given the same CPU resources. This change reduces CPU utilization of Send completion by 2-3% on my server. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-By: Tom Talpey <tom@talpey.com>
2021-08-17svcrdma: Fewer calls to wake_up() in Send completion handlerChuck Lever
Because wake_up() takes an IRQ-safe lock, it can be expensive, especially to call inside of a single-threaded completion handler. What's more, the Send wait queue almost never has waiters, so most of the time, this is an expensive no-op. As always, the goal is to reduce the average overhead of each completion, because a transport's completion handlers are single- threaded on one CPU core. This change reduces CPU utilization of the Send completion thread by 2-3% on my server. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-By: Tom Talpey <tom@talpey.com>
2021-04-14svcrdma: Pass a useful error code to the send_err tracepointChuck Lever
Capture error codes in @ret, which is passed to the send_err tracepoint, so that they can be logged when something goes awry. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-04-14svcrdma: Rename goto labels in svc_rdma_sendto()Chuck Lever
Clean up: Make the goto labels consistent with other similar functions. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-04-14svcrdma: Don't leak send_ctxt on Send errorsChuck Lever
Address a rare send_ctxt leak in the svc_rdma_sendto() error paths. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22svcrdma: Retain the page backing rq_res.head[0].iov_baseChuck Lever
svc_rdma_sendto() now waits for the NIC hardware to finish with the pages backing rq_res. We still have to release the page array in some cases, but now it's always safe to immediately re-use the page backing rq_res's head buffer. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22svcrdma: Remove unused sc_pages fieldChuck Lever
Clean up. This significantly reduces the size of struct svc_rdma_send_ctxt. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22svcrdma: Normalize Send page handlingChuck Lever
Currently svc_rdma_sendto() migrates xdr_buf pages into a separate page list and NULLs out a bunch of entries in rq_pages while the pages are under I/O. The Send completion handler then frees those pages later. Instead, let's wait for the Send completion, then handle page releasing in the nfsd thread. I'd like to avoid the cost of 250+ put_page() calls in the Send completion handler, which is single- threaded. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22svcrdma: Add a "deferred close" helperChuck Lever
Refactor a bit of commonly used logic so that every site that wants a close deferred to an nfsd thread does all the right things (set_bit(XPT_CLOSE) then enqueue). Also, once XPT_CLOSE is set on a transport, it is never cleared. If XPT_CLOSE is already set, then the close is already being handled and the enqueue can be skipped. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22svcrdma: RPCDBG_FACILITY is no longer usedChuck Lever
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-01-25svcrdma: Convert rdma_stat_sq_starve to a per-CPU counterChuck Lever
Avoid the overhead of a memory bus lock cycle for counting a value that is hardly every used. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30svcrdma: Clean up chunk tracepointsChuck Lever
We already have trace_svcrdma_decode_rseg(), which records each ingress Read segment. Instead of reporting those again when they are about to be posted as RDMA Reads, let's fire one tracepoint before posting each type of chunk. So we'll get: nfsd-1998 [002] 321.666615: svcrdma_decode_rseg: cq.id=4 cid=42 segno=0 position=0 192@0x013ca9ebfae14000:0xb0010b05 nfsd-1998 [002] 321.666615: svcrdma_decode_rseg: cq.id=4 cid=42 segno=1 position=0 7688@0x013ca9ebf914e000:0xb0010a05 nfsd-1998 [002] 321.666615: svcrdma_decode_rseg: cq.id=4 cid=42 segno=2 position=0 28@0x013ca9ebfae15000:0xb0010905 nfsd-1998 [002] 321.666622: svcrdma_decode_rqst: cq.id=4 cid=42 xid=0x013ca9eb vers=1 credits=128 proc=RDMA_NOMSG hdrlen=100 nfsd-1998 [002] 321.666642: svcrdma_post_read_chunk: cq.id=3 cid=112 sqecount=3 kworker/2:1H-221 [002] 321.673949: svcrdma_wc_read: cq.id=3 cid=112 status=SUCCESS (0/0x0) Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30svcrdma: Support multiple Write chunks in svc_rdma_map_reply_msg()Chuck Lever
Refactor: svc_rdma_map_reply_msg() is restructured to DMA map only the parts of rq_res that do not contain a result payload. This change has been tested to confirm that it does not cause a regression in the no Write chunk and single Write chunk cases. Multiple Write chunks have not been tested. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30svcrdma: Support multiple write chunks when pulling upChuck Lever
When counting the number of SGEs needed to construct a Send request, do not count result payloads. And, when copying the Reply message into the pull-up buffer, result payloads are not to be copied to the Send buffer. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30svcrdma: Use parsed chunk lists to encode Reply transport headersChuck Lever
Refactor: Instead of re-parsing the ingress RPC Call transport header when constructing the egress RPC Reply transport header, use the new parsed Write list and Reply chunk, which are version- agnostic and already XDR decoded. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30svcrdma: Use parsed chunk lists to construct RDMA WritesChuck Lever
Refactor: Instead of re-parsing the ingress RPC Call transport header when constructing RDMA Writes, use the new parsed chunk lists for the Write list and Reply chunk, which are version-agnostic and already XDR-decoded. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30svcrdma: Clean up svc_rdma_encode_reply_chunk()Chuck Lever
Refactor: Match the control flow of svc_rdma_encode_write_list(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30svcrdma: Post RDMA Writes while XDR encoding repliesChuck Lever
The only RPC/RDMA ordering requirement between RDMA Writes and RDMA Sends is that the responder must post the Writes on the Send queue before posting the Send that conveys the RPC Reply for that Write payload. The Linux NFS server implementation now has a transport method that can post result Payload Writes earlier than svc_rdma_sendto: ->xpo_result_payload() This gets RDMA Writes going earlier so they are more likely to be complete at the remote end before the Send completes. Some care must be taken with pulled-up Replies. We don't want to push the Write chunk and then send the same payload data via Send. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30NFSD: Invoke svc_encode_result_payload() in "read" NFSD encodersChuck Lever
Have the NFSD encoders annotate the boundaries of every direct-data-placement eligible result data payload. Then change svcrdma to use that annotation instead of the xdr->page_len when handling Write chunks. For NFSv4 on RDMA, that enables the ability to recognize multiple result payloads per compound. This is a pre-requisite for supporting multiple Write chunks per RPC transaction. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-11-30SUNRPC: Rename svc_encode_read_payload()Chuck Lever
Clean up: "result payload" is a less confusing name for these payloads. "READ payload" reflects only the NFS usage. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
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>
2020-07-28svcrdma: 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>
2020-07-13svcrdma: 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: 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>
2020-07-13svcrdma: 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: 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>
2020-05-18SUNRPC: Move xpt_mutex into socket xpo_sendto methodsChuck Lever
It appears that the RPC/RDMA transport does not need serialization of calls to its xpo_sendto method. Move the mutex into the socket methods that still need that serialization. Tail latencies are unambiguously better with this patch applied. fio randrw 8KB 70/30 on NFSv3, smaller numbers are better: clat percentiles (usec): With xpt_mutex: r | 99.99th=[ 8848] w | 99.99th=[ 9634] Without xpt_mutex: r | 99.99th=[ 8586] w | 99.99th=[ 8979] Serializing the construction of RPC/RDMA transport headers is not really necessary at this point, because the Linux NFS server implementation never changes its credit grant on a connection. If that should change, then svc_rdma_sendto will need to serialize access to the transport's credit grant fields. Reported-by: kbuild test robot <lkp@intel.com> [ cel: fix uninitialized variable warning ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-04-17svcrdma: Fix leak of svc_rdma_recv_ctxt objectsChuck Lever
Utilize the xpo_release_rqst transport method to ensure that each rqstp's svc_rdma_recv_ctxt object is released even when the server cannot return a Reply for that rqstp. Without this fix, each RPC whose Reply cannot be sent leaks one svc_rdma_recv_ctxt. This is a 2.5KB structure, a 4KB DMA-mapped Receive buffer, and any pages that might be part of the Reply message. The leak is infrequent unless the network fabric is unreliable or Kerberos is in use, as GSS sequence window overruns, which result in connection loss, are more common on fast transports. Fixes: 3a88092ee319 ("svcrdma: Preserve Receive buffer until svc_rdma_sendto") Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-04-17svcrdma: Fix trace point use-after-free raceChuck Lever
I hit this while testing nfsd-5.7 with kernel memory debugging enabled on my server: Mar 30 13:21:45 klimt kernel: BUG: unable to handle page fault for address: ffff8887e6c279a8 Mar 30 13:21:45 klimt kernel: #PF: supervisor read access in kernel mode Mar 30 13:21:45 klimt kernel: #PF: error_code(0x0000) - not-present page Mar 30 13:21:45 klimt kernel: PGD 3601067 P4D 3601067 PUD 87c519067 PMD 87c3e2067 PTE 800ffff8193d8060 Mar 30 13:21:45 klimt kernel: Oops: 0000 [#1] SMP DEBUG_PAGEALLOC PTI Mar 30 13:21:45 klimt kernel: CPU: 2 PID: 1933 Comm: nfsd Not tainted 5.6.0-rc6-00040-g881e87a3c6f9 #1591 Mar 30 13:21:45 klimt kernel: Hardware name: Supermicro Super Server/X10SRL-F, BIOS 1.0c 09/09/2015 Mar 30 13:21:45 klimt kernel: RIP: 0010:svc_rdma_post_chunk_ctxt+0xab/0x284 [rpcrdma] Mar 30 13:21:45 klimt kernel: Code: c1 83 34 02 00 00 29 d0 85 c0 7e 72 48 8b bb a0 02 00 00 48 8d 54 24 08 4c 89 e6 48 8b 07 48 8b 40 20 e8 5a 5c 2b e1 41 89 c6 <8b> 45 20 89 44 24 04 8b 05 02 e9 01 00 85 c0 7e 33 e9 5e 01 00 00 Mar 30 13:21:45 klimt kernel: RSP: 0018:ffffc90000dfbdd8 EFLAGS: 00010286 Mar 30 13:21:45 klimt kernel: RAX: 0000000000000000 RBX: ffff8887db8db400 RCX: 0000000000000030 Mar 30 13:21:45 klimt kernel: RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000246 Mar 30 13:21:45 klimt kernel: RBP: ffff8887e6c27988 R08: 0000000000000000 R09: 0000000000000004 Mar 30 13:21:45 klimt kernel: R10: ffffc90000dfbdd8 R11: 00c068ef00000000 R12: ffff8887eb4e4a80 Mar 30 13:21:45 klimt kernel: R13: ffff8887db8db634 R14: 0000000000000000 R15: ffff8887fc931000 Mar 30 13:21:45 klimt kernel: FS: 0000000000000000(0000) GS:ffff88885bd00000(0000) knlGS:0000000000000000 Mar 30 13:21:45 klimt kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Mar 30 13:21:45 klimt kernel: CR2: ffff8887e6c279a8 CR3: 000000081b72e002 CR4: 00000000001606e0 Mar 30 13:21:45 klimt kernel: Call Trace: Mar 30 13:21:45 klimt kernel: ? svc_rdma_vec_to_sg+0x7f/0x7f [rpcrdma] Mar 30 13:21:45 klimt kernel: svc_rdma_send_write_chunk+0x59/0xce [rpcrdma] Mar 30 13:21:45 klimt kernel: svc_rdma_sendto+0xf9/0x3ae [rpcrdma] Mar 30 13:21:45 klimt kernel: ? nfsd_destroy+0x51/0x51 [nfsd] Mar 30 13:21:45 klimt kernel: svc_send+0x105/0x1e3 [sunrpc] Mar 30 13:21:45 klimt kernel: nfsd+0xf2/0x149 [nfsd] Mar 30 13:21:45 klimt kernel: kthread+0xf6/0xfb Mar 30 13:21:45 klimt kernel: ? kthread_queue_delayed_work+0x74/0x74 Mar 30 13:21:45 klimt kernel: ret_from_fork+0x3a/0x50 Mar 30 13:21:45 klimt kernel: Modules linked in: ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue ib_umad ib_ipoib mlx4_ib sb_edac x86_pkg_temp_thermal iTCO_wdt iTCO_vendor_support coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel glue_helper crypto_simd cryptd pcspkr rpcrdma i2c_i801 rdma_ucm lpc_ich mfd_core ib_iser rdma_cm iw_cm ib_cm mei_me raid0 libiscsi mei sg scsi_transport_iscsi ioatdma wmi ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter nfsd nfs_acl lockd auth_rpcgss grace sunrpc ip_tables xfs libcrc32c mlx4_en sd_mod sr_mod cdrom mlx4_core crc32c_intel igb nvme i2c_algo_bit ahci i2c_core libahci nvme_core dca libata t10_pi qedr dm_mirror dm_region_hash dm_log dm_mod dax qede qed crc8 ib_uverbs ib_core Mar 30 13:21:45 klimt kernel: CR2: ffff8887e6c279a8 Mar 30 13:21:45 klimt kernel: ---[ end trace 87971d2ad3429424 ]--- It's absolutely not safe to use resources pointed to by the @send_wr argument of ib_post_send() _after_ that function returns. Those resources are typically freed by the Send completion handler, which can run before ib_post_send() returns. Thus the trace points currently around ib_post_send() in the server's RPC/RDMA transport are a hazard, even when they are disabled. Rearrange them so that they touch the Work Request only _before_ ib_post_send() is invoked. Fixes: bd2abef33394 ("svcrdma: Trace key RDMA API events") Fixes: 4201c7464753 ("svcrdma: Introduce svc_rdma_send_ctxt") Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16svcrdma: Avoid DMA mapping small RPC RepliesChuck Lever
On some platforms, DMA mapping part of a page is more costly than copying bytes. Indeed, not involving the I/O MMU can help the RPC/RDMA transport scale better for tiny I/Os across more RDMA devices. This is because interaction with the I/O MMU is eliminated for each of these small I/Os. Without the explicit unmapping, the NIC no longer needs to do a costly internal TLB shoot down for buffers that are just a handful of bytes. Since pull-up is now a more a frequent operation, I've introduced a trace point in the pull-up path. It can be used for debugging or user-space tools that count pull-up frequency. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16svcrdma: Fix double sync of transport header bufferChuck Lever
Performance optimization: Avoid syncing the transport buffer twice when Reply buffer pull-up is necessary. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16svcrdma: Refactor chunk list encodersChuck Lever
Same idea as the receive-side changes I did a while back: use xdr_stream helpers rather than open-coding the XDR chunk list encoders. This builds the Reply transport header from beginning to end without backtracking. As additional clean-ups, fill in documenting comments for the XDR encoders and sprinkle some trace points in the new encoding functions. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16svcrdma: Update synopsis of svc_rdma_send_reply_msg()Chuck Lever
Preparing for subsequent patches, no behavior change expected. Pass the RPC Call's svc_rdma_recv_ctxt deeper into the sendto() path. This enables passing more information about Requester- provided Write and Reply chunks into those lower-level functions. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16svcrdma: Update synopsis of svc_rdma_map_reply_msg()Chuck Lever
Preparing for subsequent patches, no behavior change expected. Pass the RPC Call's svc_rdma_recv_ctxt deeper into the sendto() path. This enables passing more information about Requester- provided Write and Reply chunks into those lower-level functions. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16svcrdma: Update synopsis of svc_rdma_send_reply_chunk()Chuck Lever
Preparing for subsequent patches, no behavior change expected. Pass the RPC Call's svc_rdma_recv_ctxt deeper into the sendto() path. This enables passing more information about Requester- provided Write and Reply chunks into the lower-level send functions. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16svcrdma: De-duplicate code that locates Write and Reply chunksChuck Lever
Cache the locations of the Requester-provided Write list and Reply chunk so that the Send path doesn't need to parse the Call header again. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16SUNRPC: Add xdr_pad_size() helperChuck Lever
Introduce a helper function to compute the XDR pad size of a variable-length XDR object. Clean up: Replace open-coded calculation of XDR pad sizes. I'm sure I haven't found every instance of this calculation. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16svcrdma: Fix double svc_rdma_send_ctxt_put() in an error pathChuck Lever
This error path is almost never executed. Found by code inspection. Fixes: 99722fe4d5a6 ("svcrdma: Persistently allocate and DMA-map Send buffers") Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16nfsd: Fix NFSv4 READ on RDMA when using readvChuck Lever
svcrdma expects that the payload falls precisely into the xdr_buf page vector. This does not seem to be the case for nfsd4_encode_readv(). This code is called only when fops->splice_read is missing or when RQ_SPLICE_OK is clear, so it's not a noticeable problem in many common cases. Add new transport method: ->xpo_read_payload so that when a READ payload does not fit exactly in rq_res's page vector, the XDR encoder can inform the RPC transport exactly where that payload is, without the payload's XDR pad. That way, when a Write chunk is present, the transport knows what byte range in the Reply message is supposed to be matched with the chunk. Note that the Linux NFS server implementation of NFS/RDMA can currently handle only one Write chunk per RPC-over-RDMA message. This simplifies the implementation of this fix. Fixes: b04209806384 ("nfsd4: allow exotic read compounds") Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=198053 Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2019-10-08svcrdma: Improve DMA mapping trace pointsChuck Lever
Capture the total size of Sends, the size of DMA map and the matching DMA unmap to ensure operation is correct. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-02-06svcrdma: Remove syslog warnings in work completion handlersChuck Lever
These can result in a lot of log noise, and are able to be triggered by client misbehavior. Since there are trace points in these handlers now, there's no need to spam the log. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-02-06svcrdma: Remove max_sge check at connect timeChuck Lever
Two and a half years ago, the client was changed to use gathered Send for larger inline messages, in commit 655fec6987b ("xprtrdma: Use gathered Send for large inline messages"). Several fixes were required because there are a few in-kernel device drivers whose max_sge is 3, and these were broken by the change. Apparently my memory is going, because some time later, I submitted commit 25fd86eca11c ("svcrdma: Don't overrun the SGE array in svc_rdma_send_ctxt"), and after that, commit f3c1fd0ee294 ("svcrdma: Reduce max_send_sges"). These too incorrectly assumed in-kernel device drivers would have more than a few Send SGEs available. The fix for the server side is not the same. This is because the fundamental problem on the server is that, whether or not the client has provisioned a chunk for the RPC reply, the server must squeeze even the most complex RPC replies into a single RDMA Send. Failing in the send path because of Send SGE exhaustion should never be an option. Therefore, instead of failing when the send path runs out of SGEs, switch to using a bounce buffer mechanism to handle RPC replies that are too complex for the device to send directly. That allows us to remove the max_sge check to enable drivers with small max_sge to work again. Reported-by: Don Dutile <ddutile@redhat.com> Fixes: 25fd86eca11c ("svcrdma: Don't overrun the SGE array in ...") Cc: stable@vger.kernel.org Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-12-27sunrpc: remove unused xpo_prep_reply_hdr callbackVasily Averin
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>
2018-11-28svcrdma: Optimize the logic that selects the R_key to invalidateChuck Lever
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>