The previous behaviour left the connection half-open in order to try
to scrape the last replies from the socket. Now that we have more reliable
reconnection, change the behaviour to close down the socket faster.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Now that we no longer use the partial shutdown code when closing the
socket, we no longer need to worry about the TCP linger2 state.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Instead we rely on SO_REUSEPORT to provide the reconnection semantics
that we need for NFSv2/v3.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
It is not safe to call xs_reset_transport() from inside xs_udp_setup_socket()
or xs_tcp_setup_socket(), since they do not own the correct locks. Instead,
do it in xs_connect().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The socket lock is currently held by the task that is requesting the
connection be established. While that is efficient in the case where
the connection happens quickly, it is racy in the case where it doesn't.
What we really want is for the connect helper to be able to block access
to the socket while it is being set up.
This patch does so by arranging to transfer the socket lock from the
task that is requesting the connect attempt, and then releasing that
lock once everything is done.
This scheme also gives us automatic protection against collisions with
the RPC close code, so we can kill the cancel_delayed_work_sync()
call in xs_close().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Now that we can reuse bound ports after a close, we never really want to
clear the transport's source port after it has been set. Doing so really
messes up the NFSv3 DRC on the server.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Now that we're setting SO_REUSEPORT, we still need to handle the
case where a connect() is attempted, but the old socket is still
lingering.
Essentially, all we want to do here is handle the error by waiting
a few seconds and then retrying.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When using TCP, we need the ability to reuse port numbers after
a disconnection, so that the NFSv3 server knows that we're the same
client. Currently we use a hack to work around the TCP socket's
TIME_WAIT: we send an RST instead of closing, which doesn't
always work...
The SO_REUSEPORT option added in Linux 3.9 allows us to bind multiple
TCP connections to the same source address+port combination, and thus
to use ordinary TCP close() instead of the current hack.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This patch fixes a sparse warning in the initial submission.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
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Merge tag 'nfs-rdma-for-3.20-part-2' of git://git.linux-nfs.org/projects/anna/nfs-rdma
NFS: RDMA Client Sparse Fixes
This patch fixes a sparse warning in the initial submission.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* tag 'nfs-rdma-for-3.20-part-2' of git://git.linux-nfs.org/projects/anna/nfs-rdma:
xprtrdma: Address sparse complaint in rpcr_to_rdmar()
With "make ARCH=x86_64 allmodconfig make C=1 CF=-D__CHECK_ENDIAN__":
linux-2.6/net/sunrpc/xprtrdma/xprt_rdma.h:273:30: warning: incorrect
type in initializer (different base types)
linux-2.6/net/sunrpc/xprtrdma/xprt_rdma.h:273:30: expected restricted
__be32 [usertype] *buffer
linux-2.6/net/sunrpc/xprtrdma/xprt_rdma.h:273:30: got unsigned int
[usertype] *rq_buffer
As far as I can tell this is a false positive.
Reported-by: kbuild-all@01.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Fix an Oopsable condition when nsm_mon_unmon is called as part of the
namespace cleanup, which now apparently happens after the utsname
has been freed.
Link: http://lkml.kernel.org/r/20150125220604.090121ae@neptune.home
Reported-by: Bruno Prémont <bonbons@linux-vserver.org>
Cc: stable@vger.kernel.org # 3.18
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
* flexfiles: (53 commits)
pnfs: lookup new lseg at lseg boundary
nfs41: .init_read and .init_write can be called with valid pg_lseg
pnfs: Update documentation on the Layout Drivers
pnfs/flexfiles: Add the FlexFile Layout Driver
nfs: count DIO good bytes correctly with mirroring
nfs41: wait for LAYOUTRETURN before retrying LAYOUTGET
nfs: add a helper to set NFS_ODIRECT_RESCHED_WRITES to direct writes
nfs41: add NFS_LAYOUT_RETRY_LAYOUTGET to layout header flags
nfs/flexfiles: send layoutreturn before freeing lseg
nfs41: introduce NFS_LAYOUT_RETURN_BEFORE_CLOSE
nfs41: allow async version layoutreturn
nfs41: add range to layoutreturn args
pnfs: allow LD to ask to resend read through pnfs
nfs: add nfs_pgio_current_mirror helper
nfs: only reset desc->pg_mirror_idx when mirroring is supported
nfs41: add a debug warning if we destroy an unempty layout
pnfs: fail comparison when bucket verifier not set
nfs: mirroring support for direct io
nfs: add mirroring support to pgio layer
pnfs: pass ds_commit_idx through the commit path
...
Conflicts:
fs/nfs/pnfs.c
fs/nfs/pnfs.h
Add a call to tally stats for a task under a different statsidx than
what's contained in the task structure.
This is needed to properly account for pnfs reads/writes when the
DS nfs version != the MDS version.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
These patches improve the scalability of the NFSoRDMA client and take large
variables off of the stack. Additionally, the GFP_* flags are updated to
match what TCP uses.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
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Merge tag 'nfs-rdma-for-3.20' of git://git.linux-nfs.org/projects/anna/nfs-rdma
NFS: Client side changes for RDMA
These patches improve the scalability of the NFSoRDMA client and take large
variables off of the stack. Additionally, the GFP_* flags are updated to
match what TCP uses.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* tag 'nfs-rdma-for-3.20' of git://git.linux-nfs.org/projects/anna/nfs-rdma: (21 commits)
xprtrdma: Update the GFP flags used in xprt_rdma_allocate()
xprtrdma: Clean up after adding regbuf management
xprtrdma: Allocate zero pad separately from rpcrdma_buffer
xprtrdma: Allocate RPC/RDMA receive buffer separately from struct rpcrdma_rep
xprtrdma: Allocate RPC/RDMA send buffer separately from struct rpcrdma_req
xprtrdma: Allocate RPC send buffer separately from struct rpcrdma_req
xprtrdma: Add struct rpcrdma_regbuf and helpers
xprtrdma: Refactor rpcrdma_buffer_create() and rpcrdma_buffer_destroy()
xprtrdma: Simplify synopsis of rpcrdma_buffer_create()
xprtrdma: Take struct ib_qp_attr and ib_qp_init_attr off the stack
xprtrdma: Take struct ib_device_attr off the stack
xprtrdma: Free the pd if ib_query_qp() fails
xprtrdma: Remove rpcrdma_ep::rep_func and ::rep_xprt
xprtrdma: Move credit update to RPC reply handler
xprtrdma: Remove rl_mr field, and the mr_chunk union
xprtrdma: Remove rpcrdma_ep::rep_ia
xprtrdma: Rename "xprt" and "rdma_connect" fields in struct rpcrdma_xprt
xprtrdma: Clean up hdrlen
xprtrdma: Display XIDs in host byte order
xprtrdma: Modernize htonl and ntohl
...
Reflect the more conservative approach used in the socket transport's
version of this transport method. An RPC buffer allocation should
avoid forcing not just FS activity, but any I/O.
In particular, two recent changes missed updating xprtrdma:
- Commit c6c8fe79a8 ("net, sunrpc: suppress allocation warning ...")
- Commit a564b8f039 ("nfs: enable swap on NFS")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
rpcrdma_{de}register_internal() are used only in verbs.c now.
MAX_RPCRDMAHDR is no longer used and can be removed.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Use the new rpcrdma_alloc_regbuf() API to shrink the amount of
contiguous memory needed for a buffer pool by moving the zero
pad buffer into a regbuf.
This is for consistency with the other uses of internally
registered memory.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The rr_base field is currently the buffer where RPC replies land.
An RPC/RDMA reply header lands in this buffer. In some cases an RPC
reply header also lands in this buffer, just after the RPC/RDMA
header.
The inline threshold is an agreed-on size limit for RDMA SEND
operations that pass from server and client. The sum of the
RPC/RDMA reply header size and the RPC reply header size must be
less than this threshold.
The largest RDMA RECV that the client should have to handle is the
size of the inline threshold. The receive buffer should thus be the
size of the inline threshold, and not related to RPCRDMA_MAX_SEGS.
RPC replies received via RDMA WRITE (long replies) are caught in
rq_rcv_buf, which is the second half of the RPC send buffer. Ie,
such replies are not involved in any way with rr_base.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The rl_base field is currently the buffer where each RPC/RDMA call
header is built.
The inline threshold is an agreed-on size limit to for RDMA SEND
operations that pass between client and server. The sum of the
RPC/RDMA header size and the RPC header size must be less than or
equal to this threshold.
Increasing the r/wsize maximum will require MAX_SEGS to grow
significantly, but the inline threshold size won't change (both
sides agree on it). The server's inline threshold doesn't change.
Since an RPC/RDMA header can never be larger than the inline
threshold, make all RPC/RDMA header buffers the size of the
inline threshold.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Because internal memory registration is an expensive and synchronous
operation, xprtrdma pre-registers send and receive buffers at mount
time, and then re-uses them for each RPC.
A "hardway" allocation is a memory allocation and registration that
replaces a send buffer during the processing of an RPC. Hardway must
be done if the RPC send buffer is too small to accommodate an RPC's
call and reply headers.
For xprtrdma, each RPC send buffer is currently part of struct
rpcrdma_req so that xprt_rdma_free(), which is passed nothing but
the address of an RPC send buffer, can find its matching struct
rpcrdma_req and rpcrdma_rep quickly via container_of / offsetof.
That means that hardway currently has to replace a whole rpcrmda_req
when it replaces an RPC send buffer. This is often a fairly hefty
chunk of contiguous memory due to the size of the rl_segments array
and the fact that both the send and receive buffers are part of
struct rpcrdma_req.
Some obscure re-use of fields in rpcrdma_req is done so that
xprt_rdma_free() can detect replaced rpcrdma_req structs, and
restore the original.
This commit breaks apart the RPC send buffer and struct rpcrdma_req
so that increasing the size of the rl_segments array does not change
the alignment of each RPC send buffer. (Increasing rl_segments is
needed to bump up the maximum r/wsize for NFS/RDMA).
This change opens up some interesting possibilities for improving
the design of xprt_rdma_allocate().
xprt_rdma_allocate() is now the one place where RPC send buffers
are allocated or re-allocated, and they are now always left in place
by xprt_rdma_free().
A large re-allocation that includes both the rl_segments array and
the RPC send buffer is no longer needed. Send buffer re-allocation
becomes quite rare. Good send buffer alignment is guaranteed no
matter what the size of the rl_segments array is.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
There are several spots that allocate a buffer via kmalloc (usually
contiguously with another data structure) and then register that
buffer internally. I'd like to split the buffers out of these data
structures to allow the data structures to scale.
Start by adding functions that can kmalloc and register a buffer,
and can manage/preserve the buffer's associated ib_sge and ib_mr
fields.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Move the details of how to create and destroy rpcrdma_req and
rpcrdma_rep structures into helper functions.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: There is one call site for rpcrdma_buffer_create(). All of
the arguments there are fields of an rpcrdma_xprt.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Reduce stack footprint of the connection upcall handler function.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Device attributes are large, and are used in more than one place.
Stash a copy in dynamically allocated memory.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If ib_query_qp() fails or the memory registration mode isn't
supported, don't leak the PD. An orphaned IB/core resource will
cause IB module removal to hang.
Fixes: bd7ed1d133 ("RPC/RDMA: check selected memory registration ...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: The rep_func field always refers to rpcrdma_conn_func().
rep_func should have been removed by commit b45ccfd25d ("xprtrdma:
Remove MEMWINDOWS registration modes").
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Reduce work in the receive CQ handler, which can be run at hardware
interrupt level, by moving the RPC/RDMA credit update logic to the
RPC reply handler.
This has some additional benefits: More header sanity checking is
done before trusting the incoming credit value, and the receive CQ
handler no longer touches the RPC/RDMA header (the CPU stalls while
waiting for the header contents to be brought into the cache).
This further extends work begun by commit e7ce710a88 ("xprtrdma:
Avoid deadlock when credit window is reset").
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Since commit 0ac531c183 ("xprtrdma: Remove REGISTER
memory registration mode"), the rl_mr pointer is no longer used
anywhere.
After removal, there's only a single member of the mr_chunk union,
so mr_chunk can be removed as well, in favor of a single pointer
field.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: This field is not used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Use consistent field names in struct rpcrdma_xprt.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Replace naked integers with a documenting macro.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
xprtsock.c and the backchannel code display XIDs in host byte order.
Follow suit in xprtrdma.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Replace htonl and ntohl with the be32 equivalents.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Make it easier to grep the system log for specific error conditions.
The wc.opcode field is not included because opcode numbers are
sparse, and because wc.opcode is not necessarily valid when
completion reports an error.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Increase the concurrency level for rpciod threads to allow for allocations
etc that happen in the RPCSEC_GSS layer. Also note that the NFSv4 byte range
locks may now need to allocate memory from inside rpciod.
Add the WQ_HIGHPRI flag to improve latency guarantees while we're at it.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
A struct xdr_stream at a page boundary might point to the end of one
page or the beginning of the next, but xdr_truncate_encode isn't
prepared to handle the former.
This can cause corruption of NFSv4 READDIR replies in the case that a
readdir entry that would have exceeded the client's dircount/maxcount
limit would have ended exactly on a 4k page boundary. You're more
likely to hit this case on large directories.
Other xdr_truncate_encode callers are probably also affected.
Reported-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com>
Tested-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com>
Fixes: 3e19ce762b "rpc: xdr_truncate_encode"
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There is nice kernel helper to escape a given strings by provided rules. Let's
use it instead of custom approach.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[bfields@redhat.com: fix length calculation]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
...move the WARN_ON_ONCE inside the following if block since they use
the same condition.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
These were useful when I was tracking down a race condition between
svc_xprt_do_enqueue and svc_get_next_xprt.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Testing has shown that the pool->sp_lock can be a bottleneck on a busy
server. Every time data is received on a socket, the server must take
that lock in order to dequeue a thread from the sp_threads list.
Address this problem by eliminating the sp_threads list (which contains
threads that are currently idle) and replacing it with a RQ_BUSY flag in
svc_rqst. This allows us to walk the sp_all_threads list under the
rcu_read_lock and find a suitable thread for the xprt by doing a
test_and_set_bit.
Note that we do still have a potential atomicity problem however with
this approach. We don't want svc_xprt_do_enqueue to set the
rqst->rq_xprt pointer unless a test_and_set_bit of RQ_BUSY returned
zero (which indicates that the thread was idle). But, by the time we
check that, the bit could be flipped by a waking thread.
To address this, we acquire a new per-rqst spinlock (rq_lock) and take
that before doing the test_and_set_bit. If that returns false, then we
can set rq_xprt and drop the spinlock. Then, when the thread wakes up,
it must set the bit under the same spinlock and can trust that if it was
already set then the rq_xprt is also properly set.
With this scheme, the case where we have an idle thread no longer needs
to take the highly contended pool->sp_lock at all, and that removes the
bottleneck.
That still leaves one issue: What of the case where we walk the whole
sp_all_threads list and don't find an idle thread? Because the search is
lockess, it's possible for the queueing to race with a thread that is
going to sleep. To address that, we queue the xprt and then search again.
If we find an idle thread at that point, we can't attach the xprt to it
directly since that might race with a different thread waking up and
finding it. All we can do is wake the idle thread back up and let it
attempt to find the now-queued xprt.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Tested-by: Chris Worley <chris.worley@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In a later patch, we'll be removing some spinlocking around the socket
and thread queueing code in order to fix some contention problems. At
that point, the stats counters will no longer be protected by the
sp_lock.
Change the counters to atomic_long_t fields, except for the
"sockets_queued" counter which will still be manipulated under a
spinlock.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Tested-by: Chris Worley <chris.worley@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
...also make the manipulation of sp_all_threads list use RCU-friendly
functions.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Tested-by: Chris Worley <chris.worley@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently all svc_create callers pass in NULL for the shutdown parm,
which then gets fixed up to be svc_rpcb_cleanup if the service uses
rpcbind.
Simplify this by instead having the the only caller that requires it
(lockd) pass in svc_rpcb_cleanup and get rid of the special casing.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The way that svc_wake_up works is a bit inefficient. It walks all of the
available pools for a service and either wakes up a task in each one or
sets the SP_TASK_PENDING flag in each one.
When svc_wake_up is called, there is no need to wake up more than one
thread to do this work. In practice, only lockd currently uses this
function and it's single threaded anyway. Thus, this just boils down to
doing a wake up of a thread in pool 0 or setting a single flag.
Eliminate the for loop in this function and change it to just operate on
pool 0. Also update the comments that sit above it and get rid of some
code that has been commented out for years now.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In a later patch, we'll want to be able to handle this flag without
holding the sp_lock. Change this field to an unsigned long flags
field, and declare a new flag in it that can be managed with atomic
bitops.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
