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path: root/include/linux/sunrpc/sched.h
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2011-04-24SUNRPC: Allow RPC calls to return ETIMEDOUT instead of EIOTrond Myklebust
On occasion, it is useful for the NFS layer to distinguish between soft timeouts and other EIO errors due to (say) encoding errors, or authentication errors. The following patch ensures that the default behaviour of the RPC layer remains to return EIO on soft timeouts (until we have audited all the callers). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-18NFSv4.1: Don't update sequence number if rpc_task is not sentBryan Schumaker
If we fail to contact the gss upcall program, then no message will be sent to the server. The client still updated the sequence number, however, and this lead to NFS4ERR_SEQ_MISMATCH for the next several RPC calls. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-10SUNRPC: Close a race in __rpc_wait_for_completion_task()Trond Myklebust
Although they run as rpciod background tasks, under normal operation (i.e. no SIGKILL), functions like nfs_sillyrename(), nfs4_proc_unlck() and nfs4_do_close() want to be fully synchronous. This means that when we exit, we want all references to the rpc_task to be gone, and we want any dentry references etc. held by that task to be released. For this reason these functions call __rpc_wait_for_completion_task(), followed by rpc_put_task() in the expectation that the latter will be releasing the last reference to the rpc_task, and thus ensuring that the callback_ops->rpc_release() has been called synchronously. This patch fixes a race which exists due to the fact that rpciod calls rpc_complete_task() (in order to wake up the callers of __rpc_wait_for_completion_task()) and then subsequently calls rpc_put_task() without ensuring that these two steps are done atomically. In order to avoid adding new spin locks, the patch uses the existing waitqueue spin lock to order the rpc_task reference count releases between the waiting process and rpciod. The common case where nobody is waiting for completion is optimised for by checking if the RPC_TASK_ASYNC flag is cleared and/or if the rpc_task reference count is 1: in those cases we drop trying to grab the spin lock, and immediately free up the rpc_task. Those few processes that need to put the rpc_task from inside an asynchronous context and that do not care about ordering are given a new helper: rpc_put_task_async(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-08-04SUNRPC: Ensure that rpc_exit() always wakes up a sleeping taskTrond Myklebust
Make rpc_exit() non-inline, and ensure that it always wakes up a task that has been queued. Kill off the now unused rpc_wake_up_task(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14SUNRPC: Reorder the struct rpc_task fieldsTrond Myklebust
This improves the packing of the rpc_task, and ensures that on 64-bit platforms the size reduces to 216 bytes. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14SUNRPC: Remove the 'tk_magic' debugging fieldTrond Myklebust
It has not triggered in almost a decade. Time to get rid of it... Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14SUNRPC: Move the task->tk_bytes_sent and tk_rtt to struct rpc_rqstTrond Myklebust
It seems strange to maintain stats for bytes_sent in one structure, and bytes received in another. Try to assemble all the RPC request-related stats in struct rpc_rqst Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14SUNRPC: Replace jiffies-based metrics with ktime-based metricsChuck Lever
Currently RPC performance metrics that tabulate elapsed time use jiffies time values. This is problematic on systems that use slow jiffies (for instance 100HZ systems built for paravirtualized environments). It is also a problem for computing precise latency statistics for advanced network transports, such as InfiniBand, that can have round-trip latencies significanly faster than a single clock tick. For the RPC client, adopt the high resolution time stamp mechanism already used by the network layer and blktrace: ktime. We use ktime format time stamps for all internal computations, and convert to milliseconds for presentation. As a result, we need only addition operations in the performance critical paths; multiply/divide is required only for presentation. We could report RTT metrics in microseconds. In fact the mountstats format is versioned to accomodate exactly this kind of interface improvement. For now, however, we'll stay with millisecond precision for presentation to maintain backwards compatibility with the handful of currently deployed user space tools. At a later point, we'll move to an API such as BDI_STATS where a finer timestamp precision can be reported. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-15rpc: add a new priority in RPC taskAlexandros Batsakis
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-15rpc: add rpc_queue_empty functionAlexandros Batsakis
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-03SUNRPC: Allow RPCs to fail quickly if the server is unreachableChuck Lever
The kernel sometimes makes RPC calls to services that aren't running. Because the kernel's RPC client always assumes the hard retry semantic when reconnecting a connection-oriented RPC transport, the underlying reconnect logic takes a long while to time out, even though the remote may have responded immediately with ECONNREFUSED. In certain cases, like upcalls to our local rpcbind daemon, or for NFS mount requests, we'd like the kernel to fail immediately if the remote service isn't reachable. This allows another transport to be tried immediately, or the pending request can be abandoned quickly. Introduce a per-request flag which controls how call_transmit_status() behaves when request transmission fails because the server cannot be reached. We don't want soft connection semantics to apply to other errors. The default case of the switch statement in call_transmit_status() no longer falls through; the fall through code is copied to the default case, and a "break;" is added. The transport's connection re-establishment timeout is also ignored for such requests. We want the request to fail immediately, so the reconnect delay is skipped. Additionally, we don't want a connect failure here to further increase the reconnect timeout value, since this request will not be retried. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17nfs41: Add backchannel processing support to RPC state machineRicardo Labiaga
Adds rpc_run_bc_task() which is called by the NFS callback service to process backchannel requests. It performs similar work to rpc_run_task() though "schedules" the backchannel task to be executed starting at the call_trasmit state in the RPC state machine. It also introduces some miscellaneous updates to the argument validation, call_transmit, and transport cleanup functions to take into account that there are now forechannel and backchannel tasks. Backchannel requests do not carry an RPC message structure, since the payload has already been XDR encoded using the existing NFSv4 callback mechanism. Introduce a new transmit state for the client to reply on to backchannel requests. This new state simply reserves the transport and issues the reply. In case of a connection related error, disconnects the transport and drops the reply. It requires the forechannel to re-establish the connection and the server to retransmit the request, as stated in NFSv4.1 section 2.9.2 "Client and Server Transport Behavior". Note: There is no need to loop attempting to reserve the transport. If EAGAIN is returned by xprt_prepare_transmit(), return with tk_status == 0, setting tk_action to call_bc_transmit. rpc_execute() will invoke it again after the task is taken off the sleep queue. [nfs41: rpc_run_bc_task() need not be exported outside RPC module] [nfs41: New call_bc_transmit RPC state] Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> [nfs41: Backchannel: No need to loop in call_bc_transmit()] Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> [rpc_count_iostats incorrectly exits early] Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> [Convert rpc_reply_expected() to inline function] [Remove unnecessary BUG_ON()] [Rename variable] Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2009-06-17nfs41: sunrpc: Export the call prepare state for session resetAndy Adamson
Signed-off-by: Andy Adamson<andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09rpc: minor cleanup of scheduler callback code\\\"J. Bruce Fields\\\
Try to make the comment here a little more clear and concise. Also, this macro definition seems unnecessary. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-28SUNRPC: Remove now-redundant RCU-safe rpc_task free pathTrond Myklebust
Now that we've tightened up the locking rules for RPC queue wakeups, we can remove the RCU-safe kfree calls... Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-28SUNRPC: Eliminate the now-redundant rpc_start_wakeup()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-28SUNRPC: Switch tasks to using the rpc_waitqueue's timer functionTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-28SUNRPC: Add a timer function to wait queues.Trond Myklebust
This is designed to replace the timeout timer in the individual rpc_tasks. By putting the timer function in the wait queue, we will eventually be able to reduce the total number of timers in use by the RPC subsystem. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-28SUNRPC: Add a (empty for the moment) destructor for rpc_wait_queuesTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25SUNRPC: Run rpc timeout functions as callbacks instead of in softirqsTrond Myklebust
An audit of the current RPC timeout functions shows that they don't really ever need to run in the softirq context. As long as the softirq is able to signal that the wakeup is due to a timeout (which it can do by setting task->tk_status to -ETIMEDOUT) then the callback functions can just run as standard task->tk_callback functions (in the rpciod/process context). The only possible border-line case would be xprt_timer() for the case of UDP, when the callback is used to reduce the size of the transport congestion window. In testing, however, the effect of moving that update to a callback would appear to be minor. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25SUNRPC: Convert users of rpc_wake_up_task to use rpc_wake_up_queued_taskTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25SUNRPC: Add a new helper rpc_wake_up_queued_task()Trond Myklebust
In all cases where we currently use rpc_wake_up_task(), we almost always know on which waitqueue the rpc_task is actually sleeping. This will allows us to simplify the queue locking in a future patch. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25SUNRPC: Allow the rpc_release() callback to be run on another workqueueTrond Myklebust
A lot of the work done by the rpc_release() callback is inappropriate for rpciod as it will often involve things like starting a new rpc call in order to clean up state after an interrupted NFSv4 open() call, or calls to mntput(), etc. This patch allows the caller of rpc_run_task() to specify that the rpc_release callback should run on a different workqueue than the default rpciod_workqueue. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-01Merge branch 'task_killable' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc * 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc: (22 commits) Remove commented-out code copied from NFS NFS: Switch from intr mount option to TASK_KILLABLE Add wait_for_completion_killable Add wait_event_killable Add schedule_timeout_killable Use mutex_lock_killable in vfs_readdir Add mutex_lock_killable Use lock_page_killable Add lock_page_killable Add fatal_signal_pending Add TASK_WAKEKILL exit: Use task_is_* signal: Use task_is_* sched: Use task_contributes_to_load, TASK_ALL and TASK_NORMAL ptrace: Use task_is_* power: Use task_is_* wait: Use TASK_NORMAL proc/base.c: Use task_is_* proc/array.c: Use TASK_REPORT perfmon: Use task_is_* ... Fixed up conflicts in NFS/sunrpc manually..
2008-01-30SUNRPC: Remove the obsolete RPC_WAITQ macroTrond Myklebust
Now that we've killed off all the users. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30SUNRPC: Unexport rpc_init_task() and rpc_execute()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30SUNRPC: allow the caller of rpc_run_task to preallocate the struct rpc_taskTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30SUNRPC: Clean up the initialisation of priority queue scheduling info.Trond Myklebust
We want the default scheduling priority (priority == 0) to remain RPC_PRIORITY_NORMAL. Also ensure that the priority wait queue scheduling is per process id instead of sometimes being per thread, and sometimes being per inode. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30SUNRPC: Clean up rpc_run_taskTrond Myklebust
Make it use the new task initialiser structure instead of acting as a wrapper. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30SUNRPC: Cleanup of rpc_task initialisationTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-12-06NFS: Switch from intr mount option to TASK_KILLABLEMatthew Wilcox
By using the TASK_KILLABLE infrastructure, we can get rid of the 'intr' mount option. We have to use _killable everywhere instead of _interruptible as we get rid of rpc_clnt_sigmask/sigunmask. Signed-off-by: Liam R. Howlett <howlett@gmail.com> Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2007-07-10SUNRPC: Remove the tk_auth macro...Trond Myklebust
We should almost always be deferencing the rpc_auth struct by means of the credential's cr_auth field instead of the rpc_clnt->cl_auth anyway. Fix up that historical mistake, and remove the macro that propagated it. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10SUNRPC: Move rpc_task->tk_task list into struct rpc_clntTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-04-30SUNRPC: Eliminate side effects from rpc_mallocChuck Lever
Currently rpc_malloc sets req->rq_buffer internally. Make this a more generic interface: return a pointer to the new buffer (or NULL) and make the caller set req->rq_buffer and req->rq_bufsize. This looks much more like kmalloc and eliminates the side effects. To fix a potential deadlock, this patch also replaces GFP_NOFS with GFP_NOWAIT in rpc_malloc. This prevents async RPCs from sleeping outside the RPC's task scheduler while allocating their buffer. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-02-20[PATCH] Fix build errors if bitop functions are do {} while macrosRalf Baechle
If one of clear_bit, change_bit or set_bit is defined as a do { } while (0) function usage of these functions in parenthesis like (foo_bit(23, &var)) while be expaned to something like (do { ... } while (0)}). resulting in a build error. This patch removes the useless parenthesis. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-03RPC: Clean up rpc_execute...Trond Myklebust
The error values are already propagated through task->tk_status, and none of the callers check one without checking the other, so we can drop the return value. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-01-24[PATCH] NFS: Fix Oops in rpc_call_sync()Trond Myklebust
Fix the Oops in http://bugzilla.linux-nfs.org/show_bug.cgi?id=138 We shouldn't be calling rpc_release_task() for tasks that are not active. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-07Merge branch 'master' of /home/trondmy/kernel/linux-2.6/ into merge_linusTrond Myklebust
2006-12-07[PATCH] lockdep: name some old style locksPeter Zijlstra
Name some of the remaning 'old_style_spin_init' locks Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-06SUNRPC: Fix up missing BKL in asynchronous RPC callback functionsTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-12-06SUNRPC: Fix a potential race in rpc_wake_up_task()Trond Myklebust
Use RCU to ensure that we can safely call rpc_finish_wakeup after we've called __rpc_do_wake_up_task. If not, there is a theoretical race, in which the rpc_task finishes executing, and gets freed first. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-12-06Fix a second potential rpc_wakeup race...Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22SUNRPC: Support for RPC child tasks no longer neededChuck Lever
The previous patches removed the last user of RPC child tasks, so we can remove support for child tasks from net/sunrpc/sched.c now. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20SUNRPC: eliminate rpc_call()Chuck Lever
Clean-up: replace rpc_call() helper with direct call to rpc_call_sync. This makes NFSv2 and NFSv3 synchronous calls more computationally efficient, and reduces stack consumption in functions that used to invoke rpc_call more than once. Test plan: Compile kernel with CONFIG_NFS enabled. Connectathon on NFS version 2, version 3, and version 4 mount points. Signed-off-by: Chuck Lever <cel@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20SUNRPC: introduce per-task RPC iostatsChuck Lever
Account for various things that occur while an RPC task is executed. Separate timers for RPC round trip and RPC execution time show how long RPC requests wait in queue before being sent. Eventually these will be accumulated at xprt_release time in one place where they can be viewed from userland. Test plan: Compile kernel with CONFIG_NFS enabled. Signed-off-by: Chuck Lever <cel@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20SUNRPC: track length of RPC wait queuesChuck Lever
RPC wait queue length will eventually be exported to userland via the RPC iostats interface. Test plan: Compile kernel with CONFIG_NFS enabled. Signed-off-by: Chuck Lever <cel@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20SUNRPC: Run rpci->queue_timeout on the rpciod workqueue instead of genericTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06SUNRPC: switchable buffer allocationChuck Lever
Add RPC client transport switch support for replacing buffer management on a per-transport basis. In the current IPv4 socket transport implementation, RPC buffers are allocated as needed for each RPC message that is sent. Some transport implementations may choose to use pre-allocated buffers for encoding, sending, receiving, and unmarshalling RPC messages, however. For transports capable of direct data placement, the buffers can be carved out of a pre-registered area of memory rather than from a slab cache. Test-plan: Millions of fsx operations. Performance characterization with "sio" and "iozone". Use oprofile and other tools to look for significant regression in CPU utilization. Signed-off-by: Chuck Lever <cel@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06NFSv4: stateful NFSv4 RPC call interfaceTrond Myklebust
The NFSv4 model requires us to complete all RPC calls that might establish state on the server whether or not the user wants to interrupt it. We may also need to schedule new work (including new RPC calls) in order to cancel the new state. The asynchronous RPC model will allow us to ensure that RPC calls always complete, but in order to allow for "synchronous" RPC, we want to add the ability to wait for completion. The waits are, of course, interruptible. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06SUNRPC: Further cleanupsTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>