summaryrefslogtreecommitdiff
path: root/net/sunrpc/sched.c
AgeCommit message (Collapse)Author
2021-10-20SUNRPC: Trace calls to .rpc_call_doneChuck Lever
Introduce a single tracepoint that can replace simple dprintk call sites in upper layer "rpc_call_done" callbacks. Example: kworker/u24:2-1254 [001] 771.026677: rpc_stats_latency: task:00000001@00000002 xid=0x16a6f3c0 rpcbindv2 GETPORT backlog=446 rtt=101 execute=555 kworker/u24:2-1254 [001] 771.026677: rpc_task_call_done: task:00000001@00000002 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpcb_getport_done kworker/u24:2-1254 [001] 771.026678: rpcb_setport: task:00000001@00000002 status=0 port=20048 Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-10-10SUNRPC: Per-rpc_clnt task PIDsChuck Lever
The current range of RPC task PIDs is 0..65535. That's not adequate for distinguishing tasks across multiple rpc_clnts running high throughput workloads. To help relieve this situation and to reduce the bottleneck of having a single atomic for assigning all RPC task PIDs, assign task PIDs per rpc_clnt. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-10-03SUNRPC: Remove WQ_HIGHPRI from xprtiodTrond Myklebust
Don't let xprtiod pre-empt softirq. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-10-03SUNRPC: Add cond_resched() at the appropriate point in __rpc_execute()Trond Myklebust
Allow tasks that need to pre-empt rpciod/xprtiod to do so when it is safe. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-06-28SUNRPC: Should wake up the privileged task firstly.Zhang Xiaoxu
When find a task from wait queue to wake up, a non-privileged task may be found out, rather than the privileged. This maybe lead a deadlock same as commit dfe1fe75e00e ("NFSv4: Fix deadlock between nfs4_evict_inode() and nfs4_opendata_get_inode()"): Privileged delegreturn task is queued to privileged list because all the slots are assigned. If there has no enough slot to wake up the non-privileged batch tasks(session less than 8 slot), then the privileged delegreturn task maybe lost waked up because the found out task can't get slot since the session is on draining. So we should treate the privileged task as the emergency task, and execute it as for as we can. Reported-by: Hulk Robot <hulkci@huawei.com> Fixes: 5fcdfacc01f3 ("NFSv4: Return delegations synchronously in evict_inode") Cc: stable@vger.kernel.org Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-06-28SUNRPC: Fix the batch tasks count wraparound.Zhang Xiaoxu
The 'queue->nr' will wraparound from 0 to 255 when only current priority queue has tasks. This maybe lead a deadlock same as commit dfe1fe75e00e ("NFSv4: Fix deadlock between nfs4_evict_inode() and nfs4_opendata_get_inode()"): Privileged delegreturn task is queued to privileged list because all the slots are assigned. When non-privileged task complete and release the slot, a non-privileged maybe picked out. It maybe allocate slot failed when the session on draining. If the 'queue->nr' has wraparound to 255, and no enough slot to service it, then the privileged delegreturn will lost to wake up. So we should avoid the wraparound on 'queue->nr'. Reported-by: Hulk Robot <hulkci@huawei.com> Fixes: 5fcdfacc01f3 ("NFSv4: Return delegations synchronously in evict_inode") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-03-08SUNRPC: Set memalloc_nofs_save() for sync tasksBenjamin Coddington
We could recurse into NFS doing memory reclaim while sending a sync task, which might result in a deadlock. Set memalloc_nofs_save for sync task execution. Fixes: a1231fda7e94 ("SUNRPC: Set memalloc_nofs_save() on all rpciod/xprtiod jobs") Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-12-02SUNRPC: rpc_wake_up() should wake up tasks in the correct orderTrond Myklebust
Currently, we wake up the tasks by priority queue ordering, which means that we ignore the batching that is supposed to help with QoS issues. Fixes: c049f8ea9a0d ("SUNRPC: Remove the bh-safe lock requirement on the rpc_wait_queue->lock") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-09-21SUNRPC: Remove remaining dprintks from sched.cChuck Lever
Clean up. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-09-21SUNRPC: Remove dprintk call sites in RPC queuing functionsChuck Lever
Remove redundant call sites or call sites that are already covered by tracepoints. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-09-21SUNRPC: Clean up RPC scheduler tracepointsChuck Lever
Remove several redundant dprintk call sites, and replace a couple of potentially useful ones with tracepoints. 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>
2020-04-04SUNRPC: Don't start a timer on an already queued rpc taskTrond Myklebust
Move the test for whether a task is already queued to prevent corruption of the timer list in __rpc_sleep_on_priority_timeout(). Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-16SUNRPC: Add a flag to avoid reference counts on credentialsTrond Myklebust
Add a flag to signal to the RPC layer that the credential is already pinned for the duration of the RPC call. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-01-15SUNRPC: Capture signalled RPC tasksChuck Lever
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-11-22SUNRPC: Capture completion of all RPC tasksChuck Lever
RPC tasks on the backchannel never invoke xprt_complete_rqst(), so there is no way to report their tk_status at completion. Also, any RPC task that exits via rpc_exit_task() before it is replied to will also disappear without a trace. Introduce a trace point that is symmetrical with rpc_task_begin that captures the termination status of each RPC task. Sample trace output for callback requests initiated on the server: kworker/u8:12-448 [003] 127.025240: rpc_task_end: task:50@3 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpc_exit_task kworker/u8:12-448 [002] 127.567310: rpc_task_end: task:51@3 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpc_exit_task kworker/u8:12-448 [001] 130.506817: rpc_task_end: task:52@3 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpc_exit_task Odd, though, that I never see trace_rpc_task_complete, either in the forward or backchannel. Should it be removed? Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-11-06SUNRPC: Avoid RPC delays when exiting suspendTrond Myklebust
Jon Hunter: "I have been tracking down another suspend/NFS related issue where again I am seeing random delays exiting suspend. The delays can be up to a couple minutes in the worst case and this is causing a suspend test we have to fail." Change the use of a deferrable work to a standard delayed one. Reported-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Fixes: 7e0a0e38fcfea ("SUNRPC: Replace the queue timer with a delayed work function") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-09-17SUNRPC: RPC level errors should always set task->tk_rpc_statusTrond Myklebust
Ensure that we set task->tk_rpc_status for all RPC level errors so that the caller can distinguish between those and server reply status errors. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20SUNRPC: Remove rpc_wake_up_queued_task_on_wq()Chuck Lever
Clean up: commit c544577daddb ("SUNRPC: Clean up transport write space handling") appears to have removed the last caller of rpc_wake_up_queued_task_on_wq(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-07-12SUNRPC: Fix transport accounting when caller specifies an rpc_xprtTrond Myklebust
Ensure that we do the required accounting for the round robin queue when the caller to rpc_init_task() has passed in a transport to be used. Reported-by: Olga Kornievskaia <aglo@umich.edu> Reported-by: Neil Brown <neilb@suse.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-07-12Merge tag 'nfs-rdma-for-5.3-1' of ↵Trond Myklebust
git://git.linux-nfs.org/projects/anna/linux-nfs 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 Lever
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>
2019-07-06Merge branch 'bh-remove'Trond Myklebust
2019-07-06SUNRPC: Move call to rpc_count_iostats before rpc_call_doneDave Wysochanski
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 the rpc_wait_queue->lockTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-07-06SUNRPC: Replace the queue timer with a delayed work functionTrond Myklebust
The queue timer function, which walks the RPC queue in order to locate candidates for waking up is one of the current constraints against removing the bh-safe queue spin locks. Replace it with a delayed work queue, so that we can do the actual rpc task wake ups from an ordinary process context. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-06-21Revert "SUNRPC: Declare RPC timers as TIMER_DEFERRABLE"Anna Schumaker
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 Gleixner
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: Declare RPC timers as TIMER_DEFERRABLETrond Myklebust
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: Simplify queue timeouts using timer_reduce()Trond Myklebust
Simplify the setting of queue timeouts by using the timer_reduce() function. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25SUNRPC: Fix up tracking of timeoutsTrond Myklebust
Add a helper to ensure that debugfs and friends print out the correct current task timeout value. 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 Myklebust
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: Remove unused argument 'action' from rpc_sleep_on_priority()Trond Myklebust
None of the callers set the 'action' argument, so let's just remove it. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25SUNRPC: Refactor rpc_sleep_on()Trond Myklebust
rpc_sleep_on() does not need to set the task->tk_callback under the queue lock, so move that out. Also refactor the check for whether the task is active. 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 Myklebust
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>
2019-03-09SUNRPC: Remove redundant calls to RPC_IS_QUEUED()Trond Myklebust
The RPC task wakeup calls all check for RPC_IS_QUEUED() before taking any locks. In addition, rpc_exit() already calls rpc_wake_up_queued_task(). Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-03-02SUNRPC: Convert remaining GFP_NOIO, and GFP_NOWAIT sites in sunrpcTrond Myklebust
Convert the remaining gfp_flags arguments in sunrpc to standard reclaiming allocations, now that we set memalloc_nofs_save() as appropriate. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-02-20SUNRPC: Set memalloc_nofs_save() on all rpciod/xprtiod jobsTrond Myklebust
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>
2018-12-19NFS/NFSD/SUNRPC: replace generic creds with 'struct cred'.NeilBrown
SUNRPC has two sorts of credentials, both of which appear as "struct rpc_cred". There are "generic credentials" which are supplied by clients such as NFS and passed in 'struct rpc_message' to indicate which user should be used to authorize the request, and there are low-level credentials such as AUTH_NULL, AUTH_UNIX, AUTH_GSS which describe the credential to be sent over the wires. This patch replaces all the generic credentials by 'struct cred' pointers - the credential structure used throughout Linux. For machine credentials, there is a special 'struct cred *' pointer which is statically allocated and recognized where needed as having a special meaning. A look-up of a low-level cred will map this to a machine credential. Signed-off-by: NeilBrown <neilb@suse.com> Acked-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-12-19SUNRPC: add side channel to use non-generic cred for rpc call.NeilBrown
The credential passed in rpc_message.rpc_cred is always a generic credential except in one instance. When gss_destroying_context() calls rpc_call_null(), it passes a specific credential that it needs to destroy. In this case the RPC acts *on* the credential rather than being authorized by it. This special case deserves explicit support and providing that will mean that rpc_message.rpc_cred is *always* generic, allowing some optimizations. So add "tk_op_cred" to rpc_task and "rpc_op_cred" to the setup data. Use this to pass the cred down from rpc_call_null(), and have rpcauth_bindcred() notice it and bind it in place. Credit to kernel test robot <fengguang.wu@intel.com> for finding a bug in earlier version of this patch. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-09-30SUNRPC: Fix priority queue fairnessTrond Myklebust
Fix up the priority queue to not batch by owner, but by queue, so that we allow '1 << priority' elements to be dequeued before switching to the next priority queue. The owner field is still used to wake up requests in round robin order by owner to avoid single processes hogging the RPC layer by loading the queues. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30SUNRPC: Test whether the task is queued before grabbing the queue spinlocksTrond Myklebust
When asked to wake up an RPC task, it makes sense to test whether or not the task is still queued. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30SUNRPC: Add a helper to wake up a sleeping rpc_task and set its statusTrond Myklebust
Add a helper that will wake up a task that is sleeping on a specific queue, and will set the value of task->tk_status. This is mainly intended for use by the transport layer to notify the task of an error condition. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-04-10sunrpc: Simplify synopsis of some trace pointsChuck Lever
Clean up: struct rpc_task carries a pointer to a struct rpc_clnt, and in fact task->tk_client is always what is passed into trace points that are already passing @task. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-02-08fix parallelism for rpc tasksOlga Kornievskaia
Hi folks, On a multi-core machine, is it expected that we can have parallel RPCs handled by each of the per-core workqueue? In testing a read workload, observing via "top" command that a single "kworker" thread is running servicing the requests (no parallelism). It's more prominent while doing these operations over krb5p mount. What has been suggested by Bruce is to try this and in my testing I see then the read workload spread among all the kworker threads. Signed-off-by: Olga Kornievskaia <kolga@netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2018-02-07Make the xprtiod workqueue unbounded.Trond Myklebust
This should help reduce the latency on replies. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2018-02-07SUNRPC: Queue latency-sensitive socket tasks to xprtiodTrond Myklebust
The response to a write_space notification is very latency sensitive, so we should queue it to the lower latency xprtiod_workqueue. This is something we already do for the other cases where an rpc task holds the transport XPRT_LOCKED bitlock. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2018-01-23SUNRPC: Micro-optimize __rpc_executeChuck Lever
The common case: There are 13 to 14 actions per RPC, and tk_callback is non-NULL in only one of them. There's no need to store a NULL in the tk_callback field during each FSM step. This slightly improves throughput results in dbench and other multi- threaded benchmarks on my two-socket client on 56Gb InfiniBand, but will probably be inconsequential on slower systems. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-01-23SUNRPC: task_run_action should display tk_callbackChuck Lever
This shows up in every RPC: kworker/4:1-19772 [004] 3467.373443: rpc_task_run_action: task:4711@2 flags=0e81 state=0005 status=0 action=call_status kworker/4:1-19772 [004] 3467.373444: rpc_task_run_action: task:4711@2 flags=0e81 state=0005 status=0 action=call_status What's actually going on is that the first iteration of the RPC scheduler is invoking the function in tk_callback (in this case, xprt_timer), then invoking call_status on the next iteration. Feeding do_action, rather than tk_action, to the "task_run_action" trace point will now always display the correct FSM step. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
generated by cgit (git 2.34.1) at 2024-06-12 02:23:48 +0000