Commit Graph

68 Commits

Author SHA1 Message Date
\"Talpey, Thomas\ 4fa016eb24 NFS/SUNRPC: support transport protocol naming
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>
2007-10-09 17:17:50 -04:00
\"Talpey, Thomas\ 3c341b0b92 SUNRPC: rename the rpc_xprtsock_create structure
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>
2007-10-09 17:17:45 -04:00
\"Talpey, Thomas\ bc25571e21 SUNRPC: Finish API to load RPC transport implementations dynamically
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>
2007-10-09 17:17:42 -04:00
\"Talpey, Thomas\ 81c098af3d SUNRPC: Provide a new API for registering transport implementations
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>
2007-10-09 17:17:40 -04:00
\"Talpey, Thomas\ 1244480976 SUNRPC: add EXPORT_SYMBOL_GPL for generic transport functions
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>
2007-10-09 17:17:36 -04:00
Frank van Maarseveen 96802a0951 SUNRPC: cleanup transport creation argument passing
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>
2007-07-10 23:40:49 -04:00
Trond Myklebust c1384c9c4c SUNRPC: fix hang due to eventd deadlock...
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>
2007-07-10 23:40:31 -04:00
Chuck Lever a509050bd3 SUNRPC: introduce rpcbind: replacement for in-kernel portmapper
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>
2007-04-30 22:17:12 -07:00
Chuck Lever c5a4dd8b7c SUNRPC: Eliminate side effects from rpc_malloc
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>
2007-04-30 22:17:11 -07:00
Chuck Lever 2bea90d43a SUNRPC: RPC buffer size estimates are too large
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>
2007-04-30 22:17:10 -07:00
Trond Myklebust 241c39b9ac RPC: Fix the TCP resend semantics for NFSv4
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>
2007-04-20 22:56:30 -07:00
Trond Myklebust d9bc125caf Merge branch 'master' of /home/trondmy/kernel/linux-2.6/
Conflicts:

	net/sunrpc/auth_gss/gss_krb5_crypto.c
	net/sunrpc/auth_gss/gss_spkm3_token.c
	net/sunrpc/clnt.c

Merge with mainline and fix conflicts.
2007-02-12 22:43:25 -08:00
Chuck Lever 43d78ef2ba NFS: disconnect before retrying NFSv4 requests over TCP
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>
2007-02-12 22:40:45 -08:00
YOSHIFUJI Hideaki cca5172a7e [NET] SUNRPC: Fix whitespace errors.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-10 23:20:13 -08:00
Chuck Lever 46121cf7d8 SUNRPC: fix print format for tk_pid
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>
2007-02-03 15:35:10 -08:00
Trond Myklebust 34161db6b1 Merge branch 'master' of /home/trondmy/kernel/linux-2.6/ into merge_linus
Conflicts:

	include/linux/sunrpc/xprt.h
	net/sunrpc/xprtsock.c
Fix up conflicts with the workqueue changes.
2006-12-07 15:48:15 -05:00
Chuck Lever 5847e1f4d0 SUNRPC: Remove pprintk() from net/sunrpc/xprt.c
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>
2006-12-06 10:46:55 -05:00
Chuck Lever c8541ecdd5 SUNRPC: Make the transport-specific setup routine allocate rpc_xprt
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>
2006-12-06 10:46:34 -05:00
David Howells 65f27f3844 WorkStruct: Pass the work_struct pointer instead of context data
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>
2006-11-22 14:55:48 +00:00
Alexey Dobriyan d8ed029d60 [SUNRPC]: trivial endianness annotations
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>
2006-09-28 18:01:21 -07:00
Trond Myklebust 6b6ca86b77 SUNRPC: Add refcounting to the struct rpc_xprt
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>
2006-09-22 23:25:01 -04:00
Trond Myklebust da45828e28 SUNRPC: Clean up soft task error handling
- 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>
2006-09-22 23:25:00 -04:00
Chuck Lever ff9aa5e56d SUNRPC: Eliminate xprt_create_proto and rpc_create_client
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>
2006-09-22 23:24:51 -04:00
Chuck Lever c2866763b4 SUNRPC: use sockaddr + size when creating remote transport endpoints
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>
2006-09-22 23:24:49 -04:00
Chuck Lever c4efcb1d3e SUNRPC: Use "sockaddr_storage" for storing RPC client's remote peer address
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>
2006-09-22 23:24:48 -04:00
Chuck Lever 4a68179d38 SUNRPC: Make RPC portmapper use per-transport storage
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>
2006-09-22 23:24:39 -04:00
Chuck Lever ec739ef03d SUNRPC: Create a helper to tell whether a transport is bound
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>
2006-09-22 23:24:39 -04:00
Trond Myklebust e0ab53deaa RPC: Ensure that we disconnect TCP socket when client requests error out
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)
2006-08-03 16:56:55 -04:00
Panagiotis Issaris 0da974f4f3 [NET]: Conversions from kmalloc+memset to k(z|c)alloc.
Signed-off-by: Panagiotis Issaris <takis@issaris.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-21 14:51:30 -07:00
Chuck Lever bf3fcf8955 SUNRPC: NFS_ROOT always uses the same XIDs
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>
2006-06-09 09:34:06 -04:00
Trond Myklebust 43ac3f2961 SUNRPC: Fix memory barriers for req->rq_received
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>
2006-03-20 13:44:51 -05:00
Chuck Lever e95b85ec9d SUNRPC: minor cleanup
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>
2006-03-20 13:44:23 -05:00
Chuck Lever 11c556b3d8 SUNRPC: provide a mechanism for collecting stats in the RPC client
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>
2006-03-20 13:44:22 -05:00
Chuck Lever ef759a2e54 SUNRPC: introduce per-task RPC iostats
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>
2006-03-20 13:44:17 -05:00
Chuck Lever 262ca07de4 SUNRPC: add a handful of per-xprt counters
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>
2006-03-20 13:44:16 -05:00
Trond Myklebust 0065db3285 SUNRPC: Clean up xprt_destroy()
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>
2006-01-06 14:58:58 -05:00
Trond Myklebust 632e3bdc50 SUNRPC: Ensure client closes the socket when server initiates a close
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>
2006-01-06 14:58:57 -05:00
Chuck Lever 0210714834 SUNRPC: switchable buffer allocation
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>
2006-01-06 14:58:55 -05:00
J. Bruce Fields ead5e1c26f SUNRPC: Provide a callback to allow free pages allocated during xdr encoding
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>
2005-10-18 23:19:43 -07:00
Trond Myklebust 5e5ce5be6f RPC: allow call_encode() to delay transmission of an RPC call.
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>
2005-10-18 14:20:11 -07:00
Chuck Lever 03bf4b707e [PATCH] RPC: parametrize various transport connect timeouts
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>
2005-09-23 12:38:53 -04:00
Chuck Lever 555ee3af16 [PATCH] RPC: clean up after nocong was removed
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>
2005-09-23 12:38:48 -04:00
Chuck Lever a58dd398f5 [PATCH] RPC: add a release_rqst callout to the RPC transport switch
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>
2005-09-23 12:38:45 -04:00
Chuck Lever 1570c1e41e [PATCH] RPC: add generic interface for adjusting the congestion window
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>
2005-09-23 12:38:43 -04:00
Chuck Lever 46c0ee8bc4 [PATCH] RPC: separate xprt_timer implementations
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>
2005-09-23 12:38:41 -04:00
Chuck Lever 49e9a89086 [PATCH] RPC: expose API for serializing access to RPC transports
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>
2005-09-23 12:38:40 -04:00
Chuck Lever 12a804698b [PATCH] RPC: expose API for serializing access to RPC transports
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>
2005-09-23 12:38:38 -04:00
Chuck Lever fe3aca290f [PATCH] RPC: add API to set transport-specific timeouts
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>
2005-09-23 12:38:36 -04:00
Chuck Lever 43118c29de [PATCH] RPC: get rid of xprt->stream
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>
2005-09-23 12:38:35 -04:00
Chuck Lever c7b2cae8a6 [PATCH] RPC: separate TCP and UDP write space callbacks
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>
2005-09-23 12:38:28 -04:00