Commit Graph
173 Commits
Author SHA1 Message Date
Trond Myklebust f42f7c2830 SUNRPC: Fix priority queue fairness
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>
2018-09-30 15:35:16 -04:00
Trond Myklebust 5ce970393b SUNRPC: Test whether the task is queued before grabbing the queue spinlocks
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>
2018-09-30 15:35:14 -04:00
Trond Myklebust 359c48c04a SUNRPC: Add a helper to wake up a sleeping rpc_task and set its status
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>
2018-09-30 15:35:14 -04:00
Chuck Lever e671edb942 sunrpc: Simplify synopsis of some trace points
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>
2018-04-10 16:06:22 -04:00
Olga Kornievskaia f515f86b34 fix parallelism for rpc tasks
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>
2018-02-08 16:24:35 -05:00
Trond Myklebust 90ea9f1b60 Make the xprtiod workqueue unbounded.
This should help reduce the latency on replies.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2018-02-07 18:31:54 -05:00
Trond Myklebust 2275cde4cc SUNRPC: Queue latency-sensitive socket tasks to xprtiod
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>
2018-02-07 09:25:52 -05:00
Chuck Lever 21ead9ff3d SUNRPC: Micro-optimize __rpc_execute
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>
2018-01-23 09:44:40 -05:00
Chuck Lever cf08d6f2e6 SUNRPC: task_run_action should display tk_callback
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>
2018-01-23 09:44:40 -05:00
Linus Torvalds c3e9c04b89 Merge tag 'nfs-for-4.15-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client updates from Anna Schumaker:
 "Stable bugfixes:
   - Revalidate "." and ".." correctly on open
   - Avoid RCU usage in tracepoints
   - Fix ugly referral attributes
   - Fix a typo in nomigration mount option
   - Revert "NFS: Move the flock open mode check into nfs_flock()"

  Features:
   - Implement a stronger send queue accounting system for NFS over RDMA
   - Switch some atomics to the new refcount_t type

  Other bugfixes and cleanups:
   - Clean up access mode bits
   - Remove special-case revalidations in nfs_opendir()
   - Improve invalidating NFS over RDMA memory for async operations that
     time out
   - Handle NFS over RDMA replies with a worqueue
   - Handle NFS over RDMA sends with a workqueue
   - Fix up replaying interrupted requests
   - Remove dead NFS over RDMA definitions
   - Update NFS over RDMA copyright information
   - Be more consistent with bool initialization and comparisons
   - Mark expected switch fall throughs
   - Various sunrpc tracepoint cleanups
   - Fix various OPEN races
   - Fix a typo in nfs_rename()
   - Use common error handling code in nfs_lock_and_join_request()
   - Check that some structures are properly cleaned up during
     net_exit()
   - Remove net pointer from dprintk()s"

* tag 'nfs-for-4.15-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (62 commits)
  NFS: Revert "NFS: Move the flock open mode check into nfs_flock()"
  NFS: Fix typo in nomigration mount option
  nfs: Fix ugly referral attributes
  NFS: super: mark expected switch fall-throughs
  sunrpc: remove net pointer from messages
  nfs: remove net pointer from messages
  sunrpc: exit_net cleanup check added
  nfs client: exit_net cleanup check added
  nfs/write: Use common error handling code in nfs_lock_and_join_requests()
  NFSv4: Replace closed stateids with the "invalid special stateid"
  NFSv4: nfs_set_open_stateid must not trigger state recovery for closed state
  NFSv4: Check the open stateid when searching for expired state
  NFSv4: Clean up nfs4_delegreturn_done
  NFSv4: cleanup nfs4_close_done
  NFSv4: Retry NFS4ERR_OLD_STATEID errors in layoutreturn
  pNFS: Retry NFS4ERR_OLD_STATEID errors in layoutreturn-on-close
  NFSv4: Don't try to CLOSE if the stateid 'other' field has changed
  NFSv4: Retry CLOSE and DELEGRETURN on NFS4ERR_OLD_STATEID.
  NFS: Fix a typo in nfs_rename()
  NFSv4: Fix open create exclusive when the server reboots
  ...
2017-11-17 14:18:00 -08:00
Chuck Lever b2bfe5915d sunrpc: Fix rpc_task_begin trace point
The rpc_task_begin trace point always display a task ID of zero.
Move the trace point call site so that it picks up the new task ID.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17 16:43:44 -05:00
Kees Cook ff861c4d64 sunrpc: Convert timers to use timer_setup()
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@poochiereds.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-nfs@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-18 12:40:27 +01:00
NeilBrown 62b2417e84 sunrpc: don't check for failure from mempool_alloc()
When mempool_alloc() is allowed to sleep (GFP_NOIO allows
sleeping) it cannot fail.
So rpc_alloc_task() cannot fail, so rpc_new_task doesn't need
to test for failure.
Consequently rpc_new_task() cannot fail, so the callers
don't need to test.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-04-20 13:44:57 -04:00
Chuck Lever 68778945e4 SUNRPC: Separate buffer pointers for RPC Call and Reply messages
For xprtrdma, the RPC Call and Reply buffers are involved in real
I/O operations.

To start with, the DMA direction of the I/O for a Call is opposite
that of a Reply.

In the current arrangement, the Reply buffer address is on a
four-byte alignment just past the call buffer. Would be friendlier
on some platforms if that was at a DMA cache alignment instead.

Because the current arrangement allocates a single memory region
which contains both buffers, the RPC Reply buffer often contains a
page boundary in it when the Call buffer is large enough (which is
frequent).

It would be a little nicer for setting up DMA operations (and
possible registration of the Reply buffer) if the two buffers were
separated, well-aligned, and contained as few page boundaries as
possible.

Now, I could just pad out the single memory region used for the pair
of buffers. But frequently that would mean a lot of unused space to
ensure the Reply buffer did not have a page boundary.

Add a separate pointer to rpc_rqst that points right to the RPC
Reply buffer. This makes no difference to xprtsock, but it will help
xprtrdma in subsequent patches.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-09-19 13:08:37 -04:00
Chuck Lever 3435c74aed SUNRPC: Generalize the RPC buffer release API
xprtrdma needs to allocate the Call and Reply buffers separately.
TBH, the reliance on using a single buffer for the pair of XDR
buffers is transport implementation-specific.

Instead of passing just the rq_buffer into the buf_free method, pass
the task structure and let buf_free take care of freeing both
XDR buffers at once.

There's a micro-optimization here. In the common case, both
xprt_release and the transport's buf_free method were checking if
rq_buffer was NULL. Now the check is done only once per RPC.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-09-19 13:08:37 -04:00
Chuck Lever 5fe6eaa1f9 SUNRPC: Generalize the RPC buffer allocation API
xprtrdma needs to allocate the Call and Reply buffers separately.
TBH, the reliance on using a single buffer for the pair of XDR
buffers is transport implementation-specific.

Transports that want to allocate separate Call and Reply buffers
will ignore the "size" argument anyway.  Don't bother passing it.

The buf_alloc method can't return two pointers. Instead, make the
method's return value an error code, and set the rq_buffer pointer
in the method itself.

This gives call_allocate an opportunity to terminate an RPC instead
of looping forever when a permanent problem occurs. If a request is
just bogus, or the transport is in a state where it can't allocate
resources for any request, there needs to be a way to kill the RPC
right there and not loop.

This immediately fixes a rare problem in the backchannel send path,
which loops if the server happens to send a CB request whose
call+reply size is larger than a page (which it shouldn't do yet).

One more issue: looks like xprt_inject_disconnect was incorrectly
placed in the failure path in call_allocate. It needs to be in the
success path, as it is for other call-sites.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-09-19 13:08:37 -04:00
Trond Myklebust f1dc237c60 SUNRPC: Reduce latency when send queue is congested
Use the low latency transport workqueue to process the task that is
next in line on the xprt->sending queue.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-06-13 12:35:51 -04:00
Trond Myklebust 40a5f1b19b SUNRPC: RPC transport queue must be low latency
rpciod can easily get congested due to the long list of queued rpc_tasks.
Having the receive queue wait in turn for those tasks to complete can
therefore be a bottleneck.

Address the problem by separating the workqueues into:
- rpciod: manages rpc_tasks
- xprtiod: manages transport related work.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-06-13 12:35:51 -04:00
Trond Myklebust 9d61498d5f SUNRPC: Allow caller to specify the transport to use
This is needed in order to allow the NFSv4.1 backchannel and
BIND_CONN_TO_SESSION function to work.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-02-05 18:48:55 -05:00
Peter Zijlstra dfd01f0260 sched/wait: Fix the signal handling fix
Jan Stancek reported that I wrecked things for him by fixing things for
Vladimir :/

His report was due to an UNINTERRUPTIBLE wait getting -EINTR, which
should not be possible, however my previous patch made this possible by
unconditionally checking signal_pending().

We cannot use current->state as was done previously, because the
instruction after the store to that variable it can be changed.  We must
instead pass the initial state along and use that.

Fixes: 68985633bc ("sched/wait: Fix signal handling in bit wait helpers")
Reported-by: Jan Stancek <jstancek@redhat.com>
Reported-by: Chris Mason <clm@fb.com>
Tested-by: Jan Stancek <jstancek@redhat.com>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com>
Tested-by: Chris Mason <clm@fb.com>
Reviewed-by: Paul Turner <pjt@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: tglx@linutronix.de
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: hpa@zytor.com
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-12-13 14:30:59 -08:00
Linus Torvalds 101688f534 Merge tag 'nfs-for-4.3-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

  Stable patches:
   - fix v4.2 SEEK on files over 2 gigs
   - Fix a layout segment reference leak when pNFS I/O falls back to inband I/O.
   - Fix recovery of recalled read delegations

  Bugfixes:
   - Fix a case where NFSv4 fails to send CLOSE after a server reboot
   - Fix sunrpc to wait for connections to complete before retrying
   - Fix sunrpc races between transport connect/disconnect and shutdown
   - Fix an infinite loop when layoutget fail with BAD_STATEID
   - nfs/filelayout: Fix NULL reference caused by double freeing of fh_array
   - Fix a bogus WARN_ON_ONCE() in O_DIRECT when layout commit_through_mds is set
   - Fix layoutreturn/close ordering issues"

* tag 'nfs-for-4.3-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFS41: make close wait for layoutreturn
  NFS: Skip checking ds_cinfo.buckets when lseg's commit_through_mds is set
  NFSv4.x/pnfs: Don't try to recover stateids twice in layoutget
  NFSv4: Recovery of recalled read delegations is broken
  NFS: Fix an infinite loop when layoutget fail with BAD_STATEID
  NFS: Do cleanup before resetting pageio read/write to mds
  SUNRPC: xs_sock_mark_closed() does not need to trigger socket autoclose
  SUNRPC: Lock the transport layer on shutdown
  nfs/filelayout: Fix NULL reference caused by double freeing of fh_array
  SUNRPC: Ensure that we wait for connections to complete before retrying
  SUNRPC: drop null test before destroy functions
  nfs: fix v4.2 SEEK on files over 2 gigs
  SUNRPC: Fix races between socket connection and destroy code
  nfs: fix pg_test page count calculation
  Failing to send a CLOSE if file is opened WRONLY and server reboots on a 4.x mount
2015-09-25 11:33:52 -07:00
Andrea Arcangeli ac5be6b47e userfaultfd: revert "userfaultfd: waitqueue: add nr wake parameter to __wake_up_locked_key"
This reverts commit 51360155ec and adapts
fs/userfaultfd.c to use the old version of that function.

It didn't look robust to call __wake_up_common with "nr == 1" when we
absolutely require wakeall semantics, but we've full control of what we
insert in the two waitqueue heads of the blocked userfaults.  No
exclusive waitqueue risks to be inserted into those two waitqueue heads
so we can as well stick to "nr == 1" of the old code and we can rely
purely on the fact no waitqueue inserted in one of the two waitqueue
heads we must enforce as wakeall, has wait->flags WQ_FLAG_EXCLUSIVE set.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thierry Reding <treding@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-22 15:09:53 -07:00
Julia Lawall 17a9618e98 SUNRPC: drop null test before destroy functions
Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-09-17 15:48:24 -04:00
Andrea Arcangeli 51360155ec userfaultfd: waitqueue: add nr wake parameter to __wake_up_locked_key
userfaultfd needs to wake all waitqueues (pass 0 as nr parameter), instead
of the current hardcoded 1 (that would wake just the first waitqueue in
the head list).

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Sanidhya Kashyap <sanidhya.gatech@gmail.com>
Cc: zhang.zhanghailiang@huawei.com
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Feiner <pfeiner@google.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Huangpeng (Peter)" <peter.huangpeng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Nicholas Mc Guire 55cc1d7806 SUNRPC: fix build-warning due to format missmatch
fix build-warning introduced by commit: f0eede10fd ("SUNRPC: use
jiffies_to_msecs for converting jiffies") which did not fixup
the format properly (my bad).

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-13 09:05:20 -04:00