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  1. 04 12月, 2009 5 次提交
    • C
      SUNRPC: Use a cached RPC client and transport for rpcbind upcalls · c526611d
      由 Chuck Lever 提交于 
      The kernel's rpcbind client creates and deletes an rpc_clnt and its
underlying transport socket for every upcall to the local rpcbind
daemon.

When starting a typical NFS server on IPv4 and IPv6, the NFS service
itself does three upcalls (one per version) times two upcalls (one
per transport) times two upcalls (one per address family), making 12,
plus another one for the initial call to unregister previous NFS
services.  Starting the NLM service adds an additional 13 upcalls,
for similar reasons.

(Currently the NFS service doesn't start IPv6 listeners, but it will
soon enough).

Instead, let's create an rpc_clnt for rpcbind upcalls during the
first local rpcbind query, and cache it.  This saves the overhead of
creating and destroying an rpc_clnt and a socket for every upcall.

The new logic also prevents the kernel from attempting an RPCB_SET or
RPCB_UNSET if it knows from the start that the local portmapper does
not support rpcbind protocol version 4.  This will cut down on the
number of rpcbind upcalls in legacy environments.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
      c526611d
    • C
      SUNRPC: Simplify synopsis of rpcb_local_clnt() · 5a462115
      由 Chuck Lever 提交于 
      Clean up: At one point, rpcb_local_clnt() handled IPv6 loopback
addresses too, but it doesn't any more; only IPv4 loopback is used
now.  Get rid of the @addr and @addrlen arguments to
rpcb_local_clnt().
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      5a462115
    • C
      SUNRPC: Allow RPCs to fail quickly if the server is unreachable · 09a21c41
      由 Chuck Lever 提交于 
      The kernel sometimes makes RPC calls to services that aren't running.
Because the kernel's RPC client always assumes the hard retry semantic
when reconnecting a connection-oriented RPC transport, the underlying
reconnect logic takes a long while to time out, even though the remote
may have responded immediately with ECONNREFUSED.

In certain cases, like upcalls to our local rpcbind daemon, or for NFS
mount requests, we'd like the kernel to fail immediately if the remote
service isn't reachable.  This allows another transport to be tried
immediately, or the pending request can be abandoned quickly.

Introduce a per-request flag which controls how call_transmit_status()
behaves when request transmission fails because the server cannot be
reached.

We don't want soft connection semantics to apply to other errors.  The
default case of the switch statement in call_transmit_status() no
longer falls through; the fall through code is copied to the default
case, and a "break;" is added.

The transport's connection re-establishment timeout is also ignored for
such requests.  We want the request to fail immediately, so the
reconnect delay is skipped.  Additionally, we don't want a connect
failure here to further increase the reconnect timeout value, since
this request will not be retried.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      09a21c41
    • C
      SUNRPC: Check explicitly for tk_status == 0 in call_transmit_status() · 206a134b
      由 Chuck Lever 提交于 
      The success case, where task->tk_status == 0, is by far the most
frequent case in call_transmit_status().

The default: arm of the switch statement in call_transmit_status()
handles the 0 case.  default: was moved close to the top of the switch
statement in call_transmit_status() under the theory that the compiler
places object code for the earliest arms of a switch statement first,
making the CPU do less work.

The default: arm of a switch statement, however, is executed only
after all the other cases have been checked.  Even if the compiler
rearranges the object code, the default: arm is the "last resort",
meaning all of the other cases have been explicitly exhausted.  That
makes the current arrangement about as inefficient as it gets for the
common case.

To fix this, add an explicit check for zero before the switch
statement.  That forces the compiler to do the zero check first, no
matter what optimizations it might try to do to the switch statement.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      206a134b
    • C
      SUNRPC: Display compressed (shorthand) IPv6 presentation addresses · dd1fd90f
      由 Chuck Lever 提交于 
      Recent changes to snprintf() introduced the %pI6c formatter, which can
display an IPv6 address with standard shorthanding.  Using a
shorthanded address can save us a few bytes of memory for each stored
presentation address, or a few bytes on the wire when sending these in
a universal address.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      dd1fd90f
  3. 14 11月, 2009 1 次提交
  5. 31 10月, 2009 1 次提交
  7. 12 10月, 2009 1 次提交
  9. 25 9月, 2009 2 次提交
  11. 24 9月, 2009 4 次提交
    • A
      sysctl: remove "struct file *" argument of ->proc_handler · 8d65af78
      由 Alexey Dobriyan 提交于 
      It's unused.

It isn't needed -- read or write flag is already passed and sysctl
shouldn't care about the rest.

It _was_ used in two places at arch/frv for some reason.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8d65af78
    • A
      headers: utsname.h redux · 2bcd57ab
      由 Alexey Dobriyan 提交于 
      * remove asm/atomic.h inclusion from linux/utsname.h --
   not needed after kref conversion
 * remove linux/utsname.h inclusion from files which do not need it

NOTE: it looks like fs/binfmt_elf.c do not need utsname.h, however
due to some personality stuff it _is_ needed -- cowardly leave ELF-related
headers and files alone.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      2bcd57ab
    • R
      sunrpc/rpc_pipe: fix kernel-doc notation · 4111d4fd
      由 Randy Dunlap 提交于 
      Fix kernel-doc notation (& warnings) in sunrpc/rpc_pipe.c.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      4111d4fd
    • N
      NFS/RPC: fix problems with reestablish_timeout and related code. · 61d0a8e6
      由 Neil Brown 提交于 
      
[[resending with correct cc:  - "vfs.kernel.org" just isn't right!]]

xprt->reestablish_timeout is used to cause TCP connection attempts to
back off if the connection fails so as not to hammer the network,
but to still allow immediate connections when there is no reason to
believe there is a problem.

It is not used for the first connection (when transport->sock is NULL)
but only on reconnects.

It is currently set:

 a/ to 0 when xs_tcp_state_change finds a state of TCP_FIN_WAIT1
    on the assumption that the client has closed the connection
    so the reconnect should be immediate when needed.
 b/ to at least XS_TCP_INIT_REEST_TO when xs_tcp_state_change
    detects TCP_CLOSING or TCP_CLOSE_WAIT on the assumption that the
    server closed the connection so a small delay at least is
    required.
 c/ as above when xs_tcp_state_change detects TCP_SYN_SENT, so that
    it is never 0 while a connection has been attempted, else
    the doubling will produce 0 and there will be no backoff.
 d/ to double is value (up to a limit) when delaying a connection,
    thus providing exponential backoff and
 e/ to XS_TCP_INIT_REEST_TO in xs_setup_tcp as simple initialisation.

So you can see it is highly dependant on xs_tcp_state_change being
called as expected.  However experimental evidence shows that
xs_tcp_state_change does not see all state changes.
("rpcdebug -m rpc trans" can help show what actually happens).

Results show:
 TCP_ESTABLISHED is reported when a connection is made.  TCP_SYN_SENT
 is never reported, so rule 'c' above is never effective.

 When the server closes the connection, TCP_CLOSE_WAIT and
 TCP_LAST_ACK *might* be reported, and TCP_CLOSE is always
 reported.  This rule 'b' above will sometimes be effective, but
 not reliably.

 When the client closes the connection, it used to result in
 TCP_FIN_WAIT1, TCP_FIN_WAIT2, TCP_CLOSE.  However since commit
 f75e6745 (SUNRPC: Fix the problem of EADDRNOTAVAIL syslog floods on
 reconnect) we don't see *any* events on client-close.  I think this
 is because xs_restore_old_callbacks is called to disconnect
 xs_tcp_state_change before the socket is closed.
 In any case, rule 'a' no longer applies.

So all that is left are rule d, which successfully doubles the
timeout which is never rest, and rule e which initialises the timeout.

Even if the rules worked as expected, there would be a problem because
a successful connection does not reset the timeout, so a sequence
of events where the server closes the connection (e.g. during failover
testing) will cause longer and longer timeouts with no good reason.

This patch:

 - sets reestablish_timeout to 0 in xs_close thus effecting rule 'a'
 - sets it to 0 in xs_tcp_data_ready to ensure that a successful
   connection resets the timeout
 - sets it to at least XS_TCP_INIT_REEST_TO after it is doubled,
   thus effecting rule c

I have not reimplemented rule b and the new version of rule c
seems sufficient.

I suspect other code in xs_tcp_data_ready needs to be revised as well.
For example I don't think connect_cookie is being incremented as often
as it should be.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      61d0a8e6
  13. 22 9月, 2009 1 次提交
  15. 19 9月, 2009 1 次提交
  17. 18 9月, 2009 1 次提交
  19. 16 9月, 2009 1 次提交
  21. 14 9月, 2009 1 次提交
  23. 12 9月, 2009 3 次提交
  25. 11 9月, 2009 1 次提交
  27. 29 8月, 2009 1 次提交
  29. 28 8月, 2009 1 次提交
  31. 26 8月, 2009 2 次提交
  33. 25 8月, 2009 1 次提交
  35. 21 8月, 2009 1 次提交
  37. 20 8月, 2009 3 次提交
  39. 15 8月, 2009 2 次提交
  41. 10 8月, 2009 6 次提交