Commit Graph

138 Commits

Author SHA1 Message Date
Alexandros Batsakis
689cf5c15b nfs: enforce FIFO ordering of operations trying to acquire slot
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-15 13:55:18 -05:00
Alexandros Batsakis
48f1861242 rpc: add rpc_queue_empty function
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-15 13:51:17 -05:00
Benny Halevy
6951867b99 nfsd41: sunrpc: move struct rpc_buffer def into sunrpc.h
Move struct rpc_buffer's definition into a sunrpc.h, a common, internal
header file, in preparation for supporting the nfsv4.1 backchannel.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: sunrpc: #include <linux/net.h> from sunrpc.h]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-09-10 12:09:06 -04:00
Alexey Dobriyan
405f55712d headers: smp_lock.h redux
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-12 12:22:34 -07:00
Andy Adamson
aae2006e9b nfs41: sunrpc: Export the call prepare state for session reset
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17 12:25:07 -07:00
Trond Myklebust
eb9b55ab4d SUNRPC: Tighten up the task locking rules in __rpc_execute()
We should probably not be testing any flags after we've cleared the
RPC_TASK_RUNNING flag, since rpc_make_runnable() is then free to assign the
rpc_task to another workqueue, which may then destroy it.

We can fix any races with rpc_make_runnable() by ensuring that we only
clear the RPC_TASK_RUNNING flag while holding the rpc_wait_queue->lock that
the task is supposed to be sleeping on (and then checking whether or not
the task really is sleeping).

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-10 20:33:16 -04:00
Trond Myklebust
a86dc496b7 SUNRPC: Remove the BKL from the callback functions
Push it into those callback functions that actually need it.

Note that all the NFS operations use their own locking, so don't need the
BKL. Ditto for the rpcbind client.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-15 18:10:57 -04:00
\\\"J. Bruce Fields\\\
a486aeda9b rpc: minor cleanup of scheduler callback code
Try to make the comment here a little more clear and concise.

Also, this macro definition seems unnecessary.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:14 -04:00
Trond Myklebust
4ccda2cdd8 SUNRPC: Clean up rpcauth_bindcred()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-03-14 13:42:35 -04:00
Trond Myklebust
af09383577 SUNRPC: Fix RPCAUTH_LOOKUP_ROOTCREDS
The current RPCAUTH_LOOKUP_ROOTCREDS flag only works for AUTH_SYS
authentication, and then only as a special case in the code. This patch
removes the auth_sys special casing, and replaces it with generic code.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-03-14 13:42:32 -04:00
Trond Myklebust
5e4424af9a SUNRPC: Remove now-redundant RCU-safe rpc_task free path
Now that we've tightened up the locking rules for RPC queue wakeups, we can
remove the RCU-safe kfree calls...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-28 23:26:28 -08:00
Trond Myklebust
f5fb7b06e4 SUNRPC: Eliminate the now-redundant rpc_start_wakeup()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-28 23:26:25 -08:00
Trond Myklebust
eb276c0e10 SUNRPC: Switch tasks to using the rpc_waitqueue's timer function
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-28 23:26:21 -08:00
Trond Myklebust
36df9aae31 SUNRPC: Add a timer function to wait queues.
This is designed to replace the timeout timer in the individual rpc_tasks.
By putting the timer function in the wait queue, we will eventually be able
to reduce the total number of timers in use by the RPC subsystem.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-28 23:21:59 -08:00
Trond Myklebust
f6a1cc8930 SUNRPC: Add a (empty for the moment) destructor for rpc_wait_queues
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-28 23:17:27 -08:00
Trond Myklebust
5d00837b90 SUNRPC: Run rpc timeout functions as callbacks instead of in softirqs
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>
2008-02-25 21:40:44 -08:00
Trond Myklebust
fda1393938 SUNRPC: Convert users of rpc_wake_up_task to use rpc_wake_up_queued_task
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25 21:40:42 -08:00
Trond Myklebust
96ef13b283 SUNRPC: Add a new helper rpc_wake_up_queued_task()
In all cases where we currently use rpc_wake_up_task(), we almost always
know on which waitqueue the rpc_task is actually sleeping. This will allows
us to simplify the queue locking in a future patch.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25 21:40:40 -08:00
Trond Myklebust
fde95c7554 SUNRPC: Clean up rpc_run_timer()
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>
2008-02-25 21:40:39 -08:00
Trond Myklebust
32bfb5c0f4 SUNRPC: Allow the rpc_release() callback to be run on another workqueue
A lot of the work done by the rpc_release() callback is inappropriate for
rpciod as it will often involve things like starting a new rpc call in
order to clean up state after an interrupted NFSv4 open() call, or
calls to mntput(), etc.

This patch allows the caller of rpc_run_task() to specify that the
rpc_release callback should run on a different workqueue than the default
rpciod_workqueue.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25 21:40:34 -08:00
Linus Torvalds
75659ca0c1 Merge branch 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc
* 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc: (22 commits)
  Remove commented-out code copied from NFS
  NFS: Switch from intr mount option to TASK_KILLABLE
  Add wait_for_completion_killable
  Add wait_event_killable
  Add schedule_timeout_killable
  Use mutex_lock_killable in vfs_readdir
  Add mutex_lock_killable
  Use lock_page_killable
  Add lock_page_killable
  Add fatal_signal_pending
  Add TASK_WAKEKILL
  exit: Use task_is_*
  signal: Use task_is_*
  sched: Use task_contributes_to_load, TASK_ALL and TASK_NORMAL
  ptrace: Use task_is_*
  power: Use task_is_*
  wait: Use TASK_NORMAL
  proc/base.c: Use task_is_*
  proc/array.c: Use TASK_REPORT
  perfmon: Use task_is_*
  ...

Fixed up conflicts in NFS/sunrpc manually..
2008-02-01 11:45:47 +11:00
Trond Myklebust
a4a874990c SUNRPC: Cleanup to remove the last users of the RPC_WAITQ declaration
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:41 -05:00
Trond Myklebust
47fe064831 SUNRPC: Unexport rpc_init_task() and rpc_execute()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:40 -05:00
Trond Myklebust
e8f5d77c80 SUNRPC: allow the caller of rpc_run_task to preallocate the struct rpc_task
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:38 -05:00
Trond Myklebust
b3ef8b3bb9 SUNRPC: Allow rpc_init_task() to initialise the rpc_task->tk_msg
In preparation for the removal of rpc_call_setup().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:31 -05:00
Trond Myklebust
3ff7576dda SUNRPC: Clean up the initialisation of priority queue scheduling info.
We want the default scheduling priority (priority == 0) to remain
RPC_PRIORITY_NORMAL.

Also ensure that the priority wait queue scheduling is per process id
instead of sometimes being per thread, and sometimes being per inode.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:30 -05:00
Trond Myklebust
84115e1cd4 SUNRPC: Cleanup of rpc_task initialisation
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:30 -05:00
Trond Myklebust
e8914c65f7 SUNRPC: Restrict sunrpc client exports
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>
2008-01-30 02:05:28 -05:00
Trond Myklebust
a6eaf8bdf9 SUNRPC: Move exported declarations to the function declarations
Do this for all RPC client related functions and XDR functions.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:28 -05:00
Pavel Emelyanov
b24b8a247f [NET]: Convert init_timer into setup_timer
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>
2008-01-28 14:53:35 -08:00
Matthew Wilcox
150030b78a NFS: Switch from intr mount option to TASK_KILLABLE
By using the TASK_KILLABLE infrastructure, we can get rid of the 'intr'
mount option.  We have to use _killable everywhere instead of _interruptible
as we get rid of rpc_clnt_sigmask/sigunmask.

Signed-off-by: Liam R. Howlett <howlett@gmail.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2007-12-06 17:40:25 -05:00
Pavel Emelyanov
ba25f9dcc4 Use helpers to obtain task pid in printks
The task_struct->pid member is going to be deprecated, so start
using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in
the kernel.

The first thing to start with is the pid, printed to dmesg - in
this case we may safely use task_pid_nr(). Besides, printks produce
more (much more) than a half of all the explicit pid usage.

[akpm@linux-foundation.org: git-drm went and changed lots of stuff]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:43 -07:00
\"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
Trond Myklebust
b247bbf1da SUNRPC: Fix a race in rpciod_down()
The commit 4ada539ed7 lead to the unpleasant
possibility of an asynchronous rpc_task being required to call
rpciod_down() when it is complete. This again means that the rpciod
workqueue may get to call destroy_workqueue on itself -> hang...

Change rpciod_up/rpciod_down to just get/put the module, and then
create/destroy the workqueues on module load/unload.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-08-07 15:13:16 -04:00
Paul Mundt
20c2df83d2 mm: Remove slab destructors from kmem_cache_create().
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.

This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-07-20 10:11:58 +09:00
Trond Myklebust
6e5b70e9d1 SUNRPC: clean up rpc_call_async/rpc_call_sync/rpc_run_task
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:30 -04:00
Trond Myklebust
188fef11db SUNRPC: Move rpc_register_client and friends into net/sunrpc/clnt.c
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:30 -04:00
Trond Myklebust
4ada539ed7 SUNRPC: Make create_client() take a reference to the rpciod workqueue
Ensures that an rpc_client always has the possibility to send asynchronous
RPC calls.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:30 -04:00
Trond Myklebust
ab418d70e1 SUNRPC: Optimise rpciod_up()
Instead of taking the mutex every time we just need to increment/decrement
rpciod_users, we can optmise by using atomic_inc_not_zero and
atomic_dec_and_test.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:30 -04:00
Trond Myklebust
90c5755ff5 SUNRPC: Kill rpc_clnt->cl_oneshot
Replace it with explicit calls to rpc_shutdown_client() or
rpc_destroy_client() (for the case of asynchronous calls).

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:29 -04:00
Trond Myklebust
34f52e3591 SUNRPC: Convert rpc_clnt->cl_users to a kref
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:28 -04:00
Trond Myklebust
c44fe70553 SUNRPC: Clean up tk_pid allocation and make it lockless
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:28 -04:00
Trond Myklebust
4bef61ff75 SUNRPC: Add a per-rpc_clnt spinlock
Use that to protect the rpc_clnt->cl_tasks list instead of using a global
lock.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:28 -04:00
Trond Myklebust
6529eba08f SUNRPC: Move rpc_task->tk_task list into struct rpc_clnt
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10 23:40:28 -04:00
Christoph Hellwig
9c9cc93ad2 SUNRPC: remove dead variable 'rpciod_running'
rpciod_running is not used at all, but due to the way DECLARE_MUTEX_LOCKED
works we don't get a warning for it.


Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-05-14 19:33:45 -04:00
Peter Zijlstra
ddce40df6e sunrpc: fix crash in rpc_malloc()
While the comment says:
 * To prevent rpciod from hanging, this allocator never sleeps,
 * returning NULL if the request cannot be serviced immediately.

The function does not actually check for NULL pointers being returned.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-05-09 17:58:00 -04:00
Chuck Lever
aa3d1faebe SUNRPC: Fix pointer arithmetic bug recently introduced in rpc_malloc/free
Use a cleaner method to find the size of an rpc_buffer.  This actually
works on x86-64!

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-05-09 17:57:59 -04:00
Geert Uytterhoeven
215d06780d Fix sunrpc warning noise
Commit c5a4dd8b7c introduced the following
compiler warnings:

net/sunrpc/sched.c:766: warning: format '%u' expects type 'unsigned int', but argument 3 has type 'size_t'
net/sunrpc/sched.c:785: warning: format '%u' expects type 'unsigned int', but argument 2 has type 'size_t'

  - Use %zu to format size_t
  - Kill 2 useless casts

Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 12:03:19 -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
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
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
2efef837fb RPC: Clean up rpc_execute...
The error values are already propagated through task->tk_status, and
none of the callers check one without checking the other, so we can
drop the return value.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-02-03 15:35:03 -08:00
Trond Myklebust
bde8f00ce6 [PATCH] NFS: Fix Oops in rpc_call_sync()
Fix the Oops in http://bugzilla.linux-nfs.org/show_bug.cgi?id=138
We shouldn't be calling rpc_release_task() for tasks that are not active.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-01-24 12:31:06 -08:00
Trond Myklebust
21b4e73692 Merge branch 'master' of /home/trondmy/kernel/linux-2.6/ into merge_linus 2006-12-07 16:35:17 -05:00
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
Christoph Lameter
e18b890bb0 [PATCH] slab: remove kmem_cache_t
Replace all uses of kmem_cache_t with struct kmem_cache.

The patch was generated using the following script:

	#!/bin/sh
	#
	# Replace one string by another in all the kernel sources.
	#

	set -e

	for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
		quilt add $file
		sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
		mv /tmp/$$ $file
		quilt refresh
	done

The script was run like this

	sh replace kmem_cache_t "struct kmem_cache"

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:25 -08:00
Trond Myklebust
6d5fcb5a52 SUNRPC: Remove BKL around the RPC socket operations etc.
All internal RPC client operations should no longer depend on the BKL,
however lockd and NFS callbacks may still require it.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-12-06 10:46:30 -05:00
Trond Myklebust
bbd5a1f9fc SUNRPC: Fix up missing BKL in asynchronous RPC callback functions
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-12-06 10:46:29 -05:00
Trond Myklebust
8aca67f0ae SUNRPC: Fix a potential race in rpc_wake_up_task()
Use RCU to ensure that we can safely call rpc_finish_wakeup after we've
called __rpc_do_wake_up_task. If not, there is a theoretical race, in which
the rpc_task finishes executing, and gets freed first.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-12-06 10:46:26 -05:00
Trond Myklebust
e6b3c4db6f Fix a second potential rpc_wakeup race...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-12-06 10:46:25 -05:00
Christophe Saout
cc4dc59e55 Subject: Re: [PATCH] Fix SUNRPC wakeup/execute race condition
The sunrpc scheduler contains a race condition that can let an RPC
task end up being neither running nor on any wait queue. The race takes
place between rpc_make_runnable (called from rpc_wake_up_task) and
__rpc_execute under the following condition:

First __rpc_execute calls tk_action which puts the task on some wait
queue. The task is dequeued by another process before __rpc_execute
continues its execution. While executing rpc_make_runnable exactly after
setting the task `running' bit and before clearing the `queued' bit
__rpc_execute picks up execution, clears `running' and subsequently
both functions fall through, both under the false assumption somebody
else took the job.

Swapping rpc_test_and_set_running with rpc_clear_queued in
rpc_make_runnable fixes that hole. This introduces another possible
race condition that can be handled by checking for `queued' after
setting the `running' bit.

Bug noticed on a 4-way x86_64 system under XEN with an NFSv4 server
on the same physical machine, apparently one of the few ways to hit
this race condition at all.

Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Christophe Saout <christophe@saout.de>
Signed-off-by: Trond Myklebust <trond.myklebust@fys.uio.no>
2006-12-06 10:46:24 -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
1a1d92c10d [PATCH] Really ignore kmem_cache_destroy return value
* Rougly half of callers already do it by not checking return value
* Code in drivers/acpi/osl.c does the following to be sure:

	(void)kmem_cache_destroy(cache);

* Those who check it printk something, however, slab_error already printed
  the name of failed cache.
* XFS BUGs on failed kmem_cache_destroy which is not the decision
  low-level filesystem driver should make. Converted to ignore.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:10 -07:00
Trond Myklebust
8014793b1b SUNRPC: rpc_delay() should not clobber the rpc_task->tk_status
Doing so prevents stuff like call_encode() from working correctly.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22 23:24:56 -04:00
Chuck Lever
39d7bbcb5b SUNRPC: remove extraneous header inclusions
include/linux/sunrpc/clnt.h already includes include/linux/sunrpc/xprt.h.
We can remove xprt.h from source files that already include clnt.h.
Likewise include/linux/sunrpc/timer.h.

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 23:24:47 -04:00
Chuck Lever
5b1eacbcd7 SUNRPC: Support for RPC child tasks no longer needed
The previous patches removed the last user of RPC child tasks, so we can
remove support for child tasks from net/sunrpc/sched.c now.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22 23:24:40 -04:00
Matthew Dobson
93d2341c75 [PATCH] mempool: use mempool_create_slab_pool()
Modify well over a dozen mempool users to call mempool_create_slab_pool()
rather than calling mempool_create() with extra arguments, saving about 30
lines of code and increasing readability.

Signed-off-by: Matthew Dobson <colpatch@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:00 -08:00
Trond Myklebust
1ebbe2b200 Merge branch 'linus' 2006-03-23 23:44:19 -05:00
Arjan van de Ven
4a3e2f711a [NET] sem2mutex: net/
Semaphore to mutex conversion.

The conversion was generated via scripts, and the result was validated
automatically via a script as well.

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 22:33:17 -08:00
Trond Myklebust
7a1218a277 SUNRPC: Ensure rpc_call_async() always calls tk_ops->rpc_release()
Currently this will not happen if we exit before rpc_new_task() was called.
Also fix up rpc_run_task() to do the same (for consistency).

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 18:11:10 -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
e19b63dafd SUNRPC: track length of RPC wait queues
RPC wait queue length will eventually be exported to userland via the RPC
iostats interface.

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 13:44:15 -05:00
Trond Myklebust
24c5d9d7ea SUNRPC: Run rpci->queue_timeout on the rpciod workqueue instead of generic
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:08 -05:00
Trond Myklebust
e6d83d5569 [PATCH] SUNRPC: Fix potential deadlock in RPC code
In rpc_wake_up() and rpc_wake_up_status(), it is possible for the call to
__rpc_wake_up_task() to fail if another thread happens to be calling
rpc_wake_up_task() on the same rpc_task.

Problem noticed by Bruno Faccini.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-14 07:57:18 -08:00
Martin Waitz
99acf04421 [PATCH] DocBook: fix some kernel-doc comments in net/sunrpc
Fix the syntax of some kernel-doc comments

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:27 -08:00
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
Trond Myklebust
e60859ac0e SUNRPC: rpc_execute should not return task->tk_status;
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06 14:58:42 -05:00
Trond Myklebust
44c288732f NFSv4: stateful NFSv4 RPC call interface
The NFSv4 model requires us to complete all RPC calls that might
 establish state on the server whether or not the user wants to
 interrupt it. We may also need to schedule new work (including
 new RPC calls) in order to cancel the new state.

 The asynchronous RPC model will allow us to ensure that RPC calls
 always complete, but in order to allow for "synchronous" RPC, we
 want to add the ability to wait for completion.
 The waits are, of course, interruptible.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06 14:58:40 -05:00
Trond Myklebust
4ce70ada1f SUNRPC: Further cleanups
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06 14:58:40 -05:00
Trond Myklebust
963d8fe533 RPC: Clean up RPC task structure
Shrink the RPC task structure. Instead of storing separate pointers
 for task->tk_exit and task->tk_release, put them in a structure.

 Also pass the user data pointer as a parameter instead of passing it via
 task->tk_calldata. This enables us to nest callbacks.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06 14:58:39 -05:00
Trond Myklebust
abbcf28f23 SUNRPC: Yet more RPC cleanups
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06 14:58:39 -05:00
Al Viro
dd0fc66fb3 [PATCH] gfp flags annotations - part 1
- added typedef unsigned int __nocast gfp_t;

 - replaced __nocast uses for gfp flags with gfp_t - it gives exactly
   the same warnings as far as sparse is concerned, doesn't change
   generated code (from gcc point of view we replaced unsigned int with
   typedef) and documents what's going on far better.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-08 15:00:57 -07:00
Randy Dunlap
dd13a285b7 [RPC]: fix sparse gfp nocast warnings
Fix nocast sparse warnings:
net/rxrpc/call.c:2013:25: warning: implicit cast to nocast type
net/rxrpc/connection.c:538:46: warning: implicit cast to nocast type
net/sunrpc/sched.c:730:36: warning: implicit cast to nocast type
net/sunrpc/sched.c:734:56: warning: implicit cast to nocast type

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-04 22:44:45 -07:00
Eric Dumazet
ba89966c19 [NET]: use __read_mostly on kmem_cache_t , DEFINE_SNMP_STAT pointers
This patch puts mostly read only data in the right section
(read_mostly), to help sharing of these data between CPUS without
memory ping pongs.

On one of my production machine, tcp_statistics was sitting in a
heavily modified cache line, so *every* SNMP update had to force a
reload.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 16:11:18 -07:00
Trond Myklebust
96651ab341 [PATCH] RPC: Shrink struct rpc_task by switching to wait_on_bit()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:07 -04:00
Trond Myklebust
d05fdb0cec [PATCH] RPC: Fix a race with rpc_restart_call()
If the task->tk_exit() wants to restart the RPC call after delaying
 then the current RPC code will clobber the timer by calling
 rpc_delete_timer() immediately after re-entering the loop in
 __rpc_execute().

 Problem noticed by Oleg Nesterov <oleg@tv-sign.ru>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2005-06-22 16:07:01 -04:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
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!
2005-04-16 15:20:36 -07:00