If we get an ECONNREFUSED error, we currently go to sleep on the
'xprt->sending' wait queue. The problem is that no timeout is set there,
and there is nothing else that will wake the task up later.
We should deal with ECONNREFUSED in call_status, given that is where we
also deal with -EHOSTDOWN, and friends.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Provide an api to attempt to load any necessary kernel RPC
client transport module automatically. By convention, the
desired module name is "xprt"+"transport name". For example,
when NFS mounting with "-o proto=rdma", attempt to load the
"xprtrdma" module.
Signed-off-by: Tom Talpey <tmtalpey@gmail.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the transport isn't bound, then we should just return ENOTCONN, letting
call_connect_status() and/or call_status() deal with retrying. Currently,
we appear to abort all pending tasks with an EIO error.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Basically, try_module_get here are pretty useless. Any other module using
this API will pin sunrpc in memory due using exported symbols.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The RPC client uses the rq_xtime field in each RPC request to determine the
round-trip time of the request. Currently, the rq_xtime field is
initialized by each transport just before it starts enqueing a request to
be sent. However, transports do not handle initializing this value
consistently; sometimes they don't initialize it at all.
To make the measurement of request round-trip time consistent for all
RPC client transport capabilities, pull rq_xtime initialization into the
RPC client's generic transport logic. Now all transports will get a
standardized RTT measure automatically, from:
xprt_transmit()
to
xprt_complete_rqst()
This makes round-trip time calculation more accurate for the TCP transport.
The socket ->sendmsg() method can return "-EAGAIN" if the socket's output
buffer is full, so the TCP transport's ->send_request() method may call
the ->sendmsg() method repeatedly until it gets all of the request's bytes
queued in the socket's buffer.
Currently, the TCP transport sets the rq_xtime field every time through
that loop so the final value is the timestamp just before the *last* call
to the underlying socket's ->sendmsg() method. After this patch, the
rq_xtime field contains a timestamp that reflects the time just before the
*first* call to ->sendmsg().
This is consequential under heavy workloads because large requests often
take multiple ->sendmsg() calls to get all the bytes of a request queued.
The TCP transport causes the request to sleep until the remote end of the
socket has received enough bytes to clear space in the socket's local
output buffer. This delay can be quite significant.
The method introduced by this patch is a more accurate measure of RTT
for stream transports, since the server can cause enough back pressure
to delay (ie increase the latency of) requests from the client.
Additionally, this patch corrects the behavior of the RDMA transport, which
entirely neglected to initialize the rq_xtime field. RPC performance
metrics for RDMA transports now display correct RPC request round trip
times.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Tom Talpey <thomas.talpey@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Recent changes to the RPC client's transport connect logic make connect
status values ECONNREFUSED and ECONNRESET impossible.
Clean up xprt_connect_status() to account for these changes.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
iwlwifi: Allow building iwl3945 without iwl4965.
wireless: Fix compile error with wifi & leds
tcp: Fix slab corruption with ipv6 and tcp6fuzz
ipv4/ipv6 compat: Fix SSM applications on 64bit kernels.
[IPSEC]: Use digest_null directly for auth
sunrpc: fix missing kernel-doc
can: Fix copy_from_user() results interpretation
Revert "ipv6: Fix typo in net/ipv6/Kconfig"
tipc: endianness annotations
ipv6: result of csum_fold() is already 16bit, no need to cast
[XFRM] AUDIT: Fix flowlabel text format ambibuity.
Fix missing sunrpc kernel-doc:
Warning(linux-2.6.25-git7//net/sunrpc/xprt.c:451): No description found for parameter 'action'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
NFSv4 requires us to ensure that we break the TCP connection before we're
allowed to retransmit a request. However in the case where we're
retransmitting several requests that have been sent on the same
connection, we need to ensure that we don't interfere with the attempt to
reconnect and/or break the connection again once it has been established.
We therefore introduce a 'connection' cookie that is bumped every time a
connection is broken. This allows requests to track if they need to force a
disconnection.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We want to ensure that req->rq_private_buf.len is updated before
req->rq_received, so that call_decode() doesn't use an old value for
req->rq_rcv_buf.len.
In 'call_decode()' itself, instead of using task->tk_status (which is set
using req->rq_received) must use the actual value of
req->rq_private_buf.len when deciding whether or not the received RPC reply
is too short.
Finally ensure that we set req->rq_rcv_buf.len to zero when retrying a
request. A typo meant that we were resetting req->rq_private_buf.len in
call_decode(), and then clobbering that value with the old rq_rcv_buf.len
again in xprt_transmit().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The rest of the networking layer uses SOCK_ASYNC_NOSPACE to signal whether
or not we have someone waiting for buffer memory. Convert the SUNRPC layer
to use the same idiom.
Remove the unlikely()s in xs_udp_write_space and xs_tcp_write_space. In
fact, the most common case will be that there is nobody waiting for buffer
space.
SOCK_NOSPACE is there to tell the TCP layer whether or not the cwnd was
limited by the application window. Ensure that we follow the same idiom as
the rest of the networking layer here too.
Finally, ensure that we clear SOCK_ASYNC_NOSPACE once we wake up, so that
write_space() doesn't keep waking things up on xprt->pending.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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>
All RPC timeout callback functions are expected to wake the task up. We can
enforce this by moving the wakeup back into rpc_run_timer.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Use updated file list for docbook files and
fix kernel-doc warnings in sunrpc:
Warning(linux-2.6.24-git12//net/sunrpc/rpc_pipe.c:689): No description found for parameter 'rpc_client'
Warning(linux-2.6.24-git12//net/sunrpc/rpc_pipe.c:765): No description found for parameter 'flags'
Warning(linux-2.6.24-git12//net/sunrpc/clnt.c:584): No description found for parameter 'tk_ops'
Warning(linux-2.6.24-git12//net/sunrpc/clnt.c:618): No description found for parameter 'bufsize'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In order to be able to support setting the timeo and retrans parameters on
a per-mountpoint basis, we move the rpc_timeout structure into the
rpc_clnt.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The sunrpc client exports are not meant to be part of any official kernel
API: they can change at the drop of a hat. Mark them as internal functions
using EXPORT_SYMBOL_GPL.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
xprt_disconnect() should really only be called when the transport shutdown
is completed, and it is time to wake up any pending tasks. Rename it to
xprt_disconnect_done() in order to reflect the semantical change.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The transport layer should do that itself whenever appropriate.
Note that the RDMA transport already assumes that it needs to call
xprt_disconnect in xprt_rdma_close().
For TCP sockets, we want to call xprt_disconnect() only after the
connection has been closed by both ends.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When scheduling the autoclose RPC call, we want to ensure that we don't
race against the test_bit() call in xprt_clear_locked().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Many-many code in the kernel initialized the timer->function
and timer->data together with calling init_timer(timer). There
is already a helper for this. Use it for networking code.
The patch is HUGE, but makes the code 130 lines shorter
(98 insertions(+), 228 deletions(-)).
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
SPIN_LOCK_UNLOCKED is deprecated, use DEFINE_SPINLOCK instead
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
To prepare for including non-sockets-based RPC transports, select
RPC transports by an identifier (to be used in following patches).
Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
To prepare for including non-sockets-based RPC transports, change the
overly suggestive name of the transport creation arguments struct.
Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Allow RPC client transport implementations to be loaded as needed, or
as they become available from distributors or third-party vendors.
Note that we leave the IP sockets implementation in sunrpc.o
permanently, as IP functionality is always available in any
kernel that runs NFS.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
To allow transport capabilities to be loaded dynamically, provide an API
for registering and unregistering the transports with the RPC client.
Eventually xprt_create_transport() will be changed to search the list of
registered transports when initializing a fresh transport.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
SUNRPC: add EXPORT_SYMBOL_GPL for generic transport functions
As a preface to allowing arbitrary transport modules to be loaded
dynamically, add EXPORT_SYMBOL_GPL for all generic transport functions
that a transport implementation might want to use.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cleanup argument passing to functions for creating an RPC transport.
Signed-off-by: Frank van Maarseveen <frankvm@frankvm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Brian Behlendorf writes:
The root cause of the NFS hang we were observing appears to be a rare
deadlock between the kernel provided usermodehelper API and the linux NFS
client. The deadlock can arise because both of these services use the
generic linux work queues. The usermodehelper API run the specified user
application in the context of the work queue. And NFS submits both cleanup
and reconnect work to the generic work queue for handling. Normally this
is fine but a deadlock can result in the following situation.
- NFS client is in a disconnected state
- [events/0] runs a usermodehelper app with an NFS dependent operation,
this triggers an NFS reconnect.
- NFS reconnect happens to be submitted to [events/0] work queue.
- Deadlock, the [events/0] work queue will never process the
reconnect because it is blocked on the previous NFS dependent
operation which will not complete.`
The solution is simply to run reconnect requests on rpciod.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Introduce a replacement for the in-kernel portmapper client that supports
all 3 versions of the rpcbind protocol. This code is not used yet.
Original code by Groupe Bull updated for the latest kernel, with multiple
bug fixes.
Note that rpcb_clnt.c does not yet support registering via versions 3 and
4 of the rpcbind protocol. That is planned for a later patch.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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>
The RPC buffer size estimation logic in net/sunrpc/clnt.c always
significantly overestimates the requirements for the buffer size.
A little instrumentation demonstrated that in fact rpc_malloc was never
allocating the buffer from the mempool, but almost always called kmalloc.
To compute the size of the RPC buffer more precisely, split p_bufsiz into
two fields; one for the argument size, and one for the result size.
Then, compute the sum of the exact call and reply header sizes, and split
the RPC buffer precisely between the two. That should keep almost all RPC
buffers within the 2KiB buffer mempool limit.
And, we can finally be rid of RPC_SLACK_SPACE!
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Fix a regression due to the patch "NFS: disconnect before retrying NFSv4
requests over TCP"
The assumption made in xprt_transmit() that the condition
"req->rq_bytes_sent == 0 and request is on the receive list"
should imply that we're dealing with a retransmission is false.
Firstly, it may simply happen that the socket send queue was full
at the time the request was initially sent through xprt_transmit().
Secondly, doing this for each request that was retransmitted implies
that we disconnect and reconnect for _every_ request that happened to
be retransmitted irrespective of whether or not a disconnection has
already occurred.
Fix is to move this logic into the call_status request timeout handler.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
RFC3530 section 3.1.1 states an NFSv4 client MUST NOT send a request
twice on the same connection unless it is the NULL procedure. Section
3.1.1 suggests that the client should disconnect and reconnect if it
wants to retry a request.
Implement this by adding an rpc_clnt flag that an ULP can use to
specify that the underlying transport should be disconnected on a
major timeout. The NFSv4 client asserts this new flag, and requests
no retries after a minor retransmit timeout.
Note that disconnecting on a retransmit is in general not safe to do
if the RPC client does not reuse the TCP port number when reconnecting.
See http://bugzilla.linux-nfs.org/show_bug.cgi?id=6
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The tk_pid field is an unsigned short. The proper print format specifier for
that type is %5u, not %4d.
Also clean up some miscellaneous print formatting nits.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
These appear to be deprecated. Removing them also gets rid of some sparse
noise.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Change the location where the rpc_xprt structure is allocated so each
transport implementation can allocate a private area from the same
chunk of memory.
Note also that xprt->ops->destroy, rather than xprt_destroy, is now
responsible for freeing rpc_xprt when the transport is destroyed.
Test plan:
Connectathon.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Pass the work_struct pointer to the work function rather than context data.
The work function can use container_of() to work out the data.
For the cases where the container of the work_struct may go away the moment the
pending bit is cleared, it is made possible to defer the release of the
structure by deferring the clearing of the pending bit.
To make this work, an extra flag is introduced into the management side of the
work_struct. This governs auto-release of the structure upon execution.
Ordinarily, the work queue executor would release the work_struct for further
scheduling or deallocation by clearing the pending bit prior to jumping to the
work function. This means that, unless the driver makes some guarantee itself
that the work_struct won't go away, the work function may not access anything
else in the work_struct or its container lest they be deallocated.. This is a
problem if the auxiliary data is taken away (as done by the last patch).
However, if the pending bit is *not* cleared before jumping to the work
function, then the work function *may* access the work_struct and its container
with no problems. But then the work function must itself release the
work_struct by calling work_release().
In most cases, automatic release is fine, so this is the default. Special
initiators exist for the non-auto-release case (ending in _NAR).
Signed-Off-By: David Howells <dhowells@redhat.com>
pure s/u32/__be32/
[AV: large part based on Alexey's patches]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
In a subsequent patch, this will allow the portmapper to take a reference
to the rpc_xprt for which it is updating the port number, fixing an Oops.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
- Ensure that the task aborts the RPC call only when it has actually timed out.
- Ensure that req->rq_majortimeo is initialised correctly.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The two function call API for creating a new RPC client is now obsolete.
Remove it.
Also, remove an unnecessary check to see whether the caller is capable of
using privileged network services. The kernel RPC client always uses a
privileged ephemeral port by default; callers are responsible for checking
the authority of users to make use of any RPC service, or for specifying
that a nonprivileged port is acceptable.
Test plan:
Repeated runs of Connectathon locking suite. Check network trace to ensure
correctness of NLM requests and replies.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Prepare for more generic transport endpoint handling needed by transports
that might use different forms of addressing, such as IPv6.
Introduce a single function call to replace the two-call
xprt_create_proto/rpc_create_client API. Define a new rpc_create_args
structure that allows callers to pass in remote endpoint addresses of
varying length.
Test-plan:
Compile kernel with CONFIG_NFS enabled.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
IPv6 addresses are big (128 bytes). Now that no RPC client consumers treat
the addr field in rpc_xprt structs as an opaque, and access it only via the
API calls, we can safely widen the field in the rpc_xprt struct to
accomodate larger addresses.
Test plan:
Compile kernel with CONFIG_NFS enabled.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Move connection and bind state that was maintained in the rpc_clnt
structure to the rpc_xprt structure. This will allow the creation of
a clean API for plugging in different types of bind mechanisms.
This brings improvements such as the elimination of a single spin lock to
control serialization for all in-kernel RPC binding. A set of per-xprt
bitops is used to serialize tasks during RPC binding, just like it now
works for making RPC transport connections.
Test-plan:
Destructive testing (unplugging the network temporarily). Connectathon
with UDP and TCP. NFSv2/3 and NFSv4 mounting should be carefully checked.
Probably need to rig a server where certain services aren't running, or
that returns an error for some typical operation.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Hide the contents and format of xprt->addr by eliminating direct uses
of the xprt->addr.sin_port field. This change is required to support
alternate RPC host address formats (eg IPv6).
Test-plan:
Destructive testing (unplugging the network temporarily). Repeated runs of
Connectathon locking suite with UDP and TCP.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If we're part way through transmitting a TCP request, and the client
errors, then we need to disconnect and reconnect the TCP socket in order to
avoid confusing the server.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from 031a50c8b9ea82616abd4a4e18021a25848941ce commit)
The XID generator uses get_random_bytes to generate an initial XID.
NFS_ROOT starts up before the random driver, though, so get_random_bytes
doesn't set a random XID for NFS_ROOT. This causes NFS_ROOT mount points
to reuse XIDs every time the client is booted. If the client boots often
enough, the server will start serving old replies out of its DRC.
Use net_random() instead.
Test plan:
I/O intensive workloads should perform well and generate no errors. Traces
taken during client reboots should show that NFS_ROOT mounts use unique
XIDs after every reboot.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We need to ensure that all writes to the XDR buffers are done before
req->rq_received is visible to other processors.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
RPC_DEBUG_DATA no longer needed in net/sunrpc/xprt.c.
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>
Add a simple mechanism for collecting stats in the RPC client. Stats are
tabulated during xprt_release. Note that per_cpu shenanigans are not
required here because the RPC client already serializes on the transport
write lock.
Test plan:
Compile kernel with CONFIG_NFS enabled. Basic performance regression
testing with high-speed networking and high performance server.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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>
Monitor generic transport events. Add a transport switch callout to
format transport counters for export to user-land.
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>
We ought never to be calling xprt_destroy() if there are still active
rpc_tasks. Optimise away the broken code that attempts to "fix" that case.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the server decides to close the RPC socket, we currently don't actually
respond until either another RPC call is scheduled, or until xprt_autoclose()
gets called by the socket expiry timer (which may be up to 5 minutes
later).
This patch ensures that xprt_autoclose() is called much sooner if the
server closes the socket.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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>
For privacy, we need to allocate pages to store the encrypted data (passed
in pages can't be used without the risk of corrupting data in the page cache).
So we need a way to free that memory after the request has been transmitted.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, call_encode will cause the entire RPC call to abort if it returns
an error. This is unnecessarily rigid, and gets in the way of attempts
to allow the NFSv4 layer to order RPC calls that carry sequence ids.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Each transport implementation can now set unique bind, connect,
reestablishment, and idle timeout values. These are variables,
allowing the values to be modified dynamically. This permits
exponential backoff of any of these values, for instance.
As an example, we implement exponential backoff for the connection
reestablishment timeout.
Test-plan:
Destructive testing (unplugging the network temporarily). Connectathon
with UDP and TCP.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean-up: Move some macros that are specific to the Van Jacobson
implementation into xprt.c. Get rid of the cong_wait field in
rpc_xprt, which is no longer used. Get rid of xprt_clear_backlog.
Test-plan:
Compile with CONFIG_NFS enabled.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The final place where congestion control state is adjusted is in
xprt_release, where each request is finally released. Add a callout
there to allow transports to perform additional processing when a
request is about to be released.
Test-plan:
Use WAN simulation to cause sporadic bursty packet loss. Look for significant
regression in performance or client stability.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
A new interface that allows transports to adjust their congestion window
using the Van Jacobson implementation in xprt.c is provided.
Test-plan:
Use WAN simulation to cause sporadic bursty packet loss. Look for
significant regression in performance or client stability.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Allow transports to hook the retransmit timer interrupt. Some transports
calculate their congestion window here so that a retransmit timeout has
immediate effect on the congestion window.
Test-plan:
Use WAN simulation to cause sporadic bursty packet loss. Look for significant
regression in performance or client stability.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The next method we abstract is the one that releases a transport,
allowing another task to have access to the transport.
Again, one generic version of this is provided for transports that
don't need the RPC client to perform congestion control, and one
version is for transports that can use the original Van Jacobson
implementation in xprt.c.
Test-plan:
Use WAN simulation to cause sporadic bursty packet loss. Look for
significant regression in performance or client stability.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The next several patches introduce an API that allows transports to
choose whether the RPC client provides congestion control or whether
the transport itself provides it.
The first method we abstract is the one that serializes access to the
RPC transport to prevent the bytes from different requests from mingling
together. This method provides proper request serialization and the
opportunity to prevent new requests from being started because the
transport is congested.
The normal situation is for the transport to handle congestion control
itself. Although NFS over UDP was first, it has been recognized after
years of experience that having the transport provide congestion control
is much better than doing it in the RPC client. Thus TCP, and probably
every future transport implementation, will use the default method,
xprt_lock_write, provided in xprt.c, which does not provide any kind
of congestion control. UDP can continue using the xprt.c-provided
Van Jacobson congestion avoidance implementation.
Test-plan:
Use WAN simulation to cause sporadic bursty packet loss. Look for significant
regression in performance or client stability.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Prepare the way to remove the "xprt->nocong" variable by adding a callout
to the RPC client transport switch API to handle setting RPC retransmit
timeouts.
Add a pair of generic helper functions that provide the ability to set a
simple fixed timeout, or to set a timeout based on the state of a round-
trip estimator.
Test-plan:
Use WAN simulation to cause sporadic bursty packet loss. Look for significant
regression in performance or client stability.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Now we can fix up the last few places that use the "xprt->stream"
variable, and get rid of it from the rpc_xprt structure.
Test-plan:
Destructive testing (unplugging the network temporarily). Connectathon
with UDP and TCP.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Split the socket write space callback function into a TCP version and UDP
version, eliminating one dependence on the "xprt->stream" variable.
Keep the common pieces of this path in xprt.c so other transports can use
it too.
Test-plan:
Write-intensive workload on a single mount point.
Version: Thu, 11 Aug 2005 16:07:51 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean-up: change some comments to reflect the realities of the new RPC
transport switch mechanism. Get rid of unused xprt_receive() prototype.
Also, organize function prototypes in xprt.h by usage and scope.
Test-plan:
Compile kernel with CONFIG_NFS enabled.
Version: Thu, 11 Aug 2005 16:07:21 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean-up: remove only reference to xprt->pending from the socket transport
implementation. This makes a cleaner interface for other transport
implementations as well.
Test-plan:
Compile kernel with CONFIG_NFS enabled.
Version: Thu, 11 Aug 2005 16:06:52 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean-up: get rid of a name reference to sockets in the generic parts of the
RPC client by renaming the sockstate field in the rpc_xprt structure.
Test-plan:
Compile kernel with CONFIG_NFS enabled.
Version: Thu, 11 Aug 2005 16:05:53 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean-up: Replace the xprt_lock with something more aptly named. This lock
single-threads the XID and request slot reservation process.
Test-plan:
Compile kernel with CONFIG_NFS enabled.
Version: Thu, 11 Aug 2005 16:05:26 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean-up: replace a name reference to sockets in the generic parts of the RPC
client by renaming sock_lock in the rpc_xprt structure.
Test-plan:
Compile kernel with CONFIG_NFS enabled.
Version: Thu, 11 Aug 2005 16:05:00 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Introduce block header comments and a function naming convention to the
socket transport implementation. Provide a debug setting for transports
that is separate from RPCDBG_XPRT. Eliminate xprt_default_timeout().
Provide block comments for exposed interfaces in xprt.c, and eliminate
the useless obvious comments.
Convert printk's to dprintk's.
Test-plan:
Compile kernel with CONFIG_NFS enabled.
Version: Thu, 11 Aug 2005 16:04:04 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Move the bulk of client-side socket-specific code into a separate source
file, net/sunrpc/xprtsock.c.
Test-plan:
Millions of fsx operations. Performance characterization such as "sio" or
"iozone". Destructive testing (unplugging the network temporarily, server
reboots). Connectathon with v2, v3, and v4.
Version: Thu, 11 Aug 2005 16:03:38 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean-up: Move some code that is common to both RPC client- and server-side
socket transports into its own source file, net/sunrpc/socklib.c.
Test-plan:
Compile kernel with CONFIG_NFS enabled. Millions of fsx operations over
UDP, client and server. Connectathon over UDP.
Version: Thu, 11 Aug 2005 16:03:09 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Implement a best practice: don't use exponential backoff when computing
retransmit timeout values on TCP connections, but simply retransmit
at regular intervals.
This also fixes a bug introduced when xprt_reset_majortimeo() was added.
Test-plan:
Enable RPC debugging and watch timeout behavior on a NFS/TCP mount.
Version: Thu, 11 Aug 2005 16:02:19 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Fix up xprt_connect_status: the soft timeout logic was clobbering tk_status,
so TCP connect errors were not properly reported on soft mounts.
Test-plan:
Destructive testing (unplugging the network temporarily). Connectathon
with UDP and TCP.
Version: Thu, 11 Aug 2005 16:01:28 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In __xprt_lock_write() we check to see if `task' is NULL, but in other places
we just go and dereference it.
`task' shouldn't be NULL anyway, so remove this test.
This defect was found automatically by Coverity Prevent, a static analysis
tool.
Signed-off-by: Zaur Kambarov <zkambarov@coverity.com>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make the socket transport kick the event queue to start socket connects
immediately. This should improve responsiveness of applications that are
sensitive to slow mount operations (like automounters).
We are now also careful to cancel the connect worker before destroying
the xprt. This eliminates a race where xprt_destroy can finish before
the connect worker is even allowed to run.
Test-plan:
Destructive testing (unplugging the network temporarily). Connectathon
with UDP and TCP. Hard-code impossibly small connect timeout.
Version: Fri, 29 Apr 2005 15:32:01 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When the network layer reports a connection close, the RPC task
waiting to reconnect should be notified so it can retry immediately
instead of waiting for the normal connection establishment timeout.
This reverts a change made in 2.6.6 as part of adding client support
for RPC over TCP socket idle timeouts.
Test-plan:
Destructive testing with NFS over TCP mounts.
Version: Fri, 29 Apr 2005 15:31:46 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cancel autodisconnect requests inside xprt_transmit() in order to avoid
races.
Use more efficient del_singleshot_timer_sync()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
