* 'for-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: fix build failure introduced by s/freezeable/freezable/
workqueue: add system_freezeable_wq
rds/ib: use system_wq instead of rds_ib_fmr_wq
net/9p: replace p9_poll_task with a work
net/9p: use system_wq instead of p9_mux_wq
xfs: convert to alloc_workqueue()
reiserfs: make commit_wq use the default concurrency level
ocfs2: use system_wq instead of ocfs2_quota_wq
ext4: convert to alloc_workqueue()
scsi/scsi_tgt_lib: scsi_tgtd isn't used in memory reclaim path
scsi/be2iscsi,qla2xxx: convert to alloc_workqueue()
misc/iwmc3200top: use system_wq instead of dedicated workqueues
i2o: use alloc_workqueue() instead of create_workqueue()
acpi: kacpi*_wq don't need WQ_MEM_RECLAIM
fs/aio: aio_wq isn't used in memory reclaim path
input/tps6507x-ts: use system_wq instead of dedicated workqueue
cpufreq: use system_wq instead of dedicated workqueues
wireless/ipw2x00: use system_wq instead of dedicated workqueues
arm/omap: use system_wq in mailbox
workqueue: use WQ_MEM_RECLAIM instead of WQ_RESCUER
Although they run as rpciod background tasks, under normal operation
(i.e. no SIGKILL), functions like nfs_sillyrename(), nfs4_proc_unlck()
and nfs4_do_close() want to be fully synchronous. This means that when we
exit, we want all references to the rpc_task to be gone, and we want
any dentry references etc. held by that task to be released.
For this reason these functions call __rpc_wait_for_completion_task(),
followed by rpc_put_task() in the expectation that the latter will be
releasing the last reference to the rpc_task, and thus ensuring that the
callback_ops->rpc_release() has been called synchronously.
This patch fixes a race which exists due to the fact that
rpciod calls rpc_complete_task() (in order to wake up the callers of
__rpc_wait_for_completion_task()) and then subsequently calls
rpc_put_task() without ensuring that these two steps are done atomically.
In order to avoid adding new spin locks, the patch uses the existing
waitqueue spin lock to order the rpc_task reference count releases between
the waiting process and rpciod.
The common case where nobody is waiting for completion is optimised for by
checking if the RPC_TASK_ASYNC flag is cleared and/or if the rpc_task
reference count is 1: in those cases we drop trying to grab the spin lock,
and immediately free up the rpc_task.
Those few processes that need to put the rpc_task from inside an
asynchronous context and that do not care about ordering are given a new
helper: rpc_put_task_async().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
WQ_RESCUER is now an internal flag and should only be used in the
workqueue implementation proper. Use WQ_MEM_RECLAIM instead.
This doesn't introduce any functional difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: dm-devel@redhat.com
Cc: Neil Brown <neilb@suse.de>
* 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (67 commits)
SUNRPC: Cleanup duplicate assignment in rpcauth_refreshcred
nfs: fix unchecked value
Ask for time_delta during fsinfo probe
Revalidate caches on lock
SUNRPC: After calling xprt_release(), we must restart from call_reserve
NFSv4: Fix up the 'dircount' hint in encode_readdir
NFSv4: Clean up nfs4_decode_dirent
NFSv4: nfs4_decode_dirent must clear entry->fattr->valid
NFSv4: Fix a regression in decode_getfattr
NFSv4: Fix up decode_attr_filehandle() to handle the case of empty fh pointer
NFS: Ensure we check all allocation return values in new readdir code
NFS: Readdir plus in v4
NFS: introduce generic decode_getattr function
NFS: check xdr_decode for errors
NFS: nfs_readdir_filler catch all errors
NFS: readdir with vmapped pages
NFS: remove page size checking code
NFS: decode_dirent should use an xdr_stream
SUNRPC: Add a helper function xdr_inline_peek
NFS: remove readdir plus limit
...
Change "return (EXPR);" to "return EXPR;"
return is not a function, parentheses are not required.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This will allow us to save the original generic cred in rpc_message, so
that if we migrate from one server to another, we can generate a new bound
cred without having to punt back to the NFS layer.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Now that rpc_run_task() is the sole entry point for RPC calls, we can move
the remaining rpc_client-related initialisation of struct rpc_task from
sched.c into clnt.c.
Also move rpc_killall_tasks() into the same file, since that too is
relative to the rpc_clnt.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Make rpc_exit() non-inline, and ensure that it always wakes up a task that
has been queued.
Kill off the now unused rpc_wake_up_task().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently RPC performance metrics that tabulate elapsed time use
jiffies time values. This is problematic on systems that use slow
jiffies (for instance 100HZ systems built for paravirtualized
environments). It is also a problem for computing precise latency
statistics for advanced network transports, such as InfiniBand,
that can have round-trip latencies significanly faster than a single
clock tick.
For the RPC client, adopt the high resolution time stamp mechanism
already used by the network layer and blktrace: ktime.
We use ktime format time stamps for all internal computations, and
convert to milliseconds for presentation. As a result, we need only
addition operations in the performance critical paths; multiply/divide
is required only for presentation.
We could report RTT metrics in microseconds. In fact the mountstats
format is versioned to accomodate exactly this kind of interface
improvement.
For now, however, we'll stay with millisecond precision for
presentation to maintain backwards compatibility with the handful of
currently deployed user space tools. At a later point, we'll move to
an API such as BDI_STATS where a finer timestamp precision can be
reported.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Also have it return an ERR_PTR(-ENOMEM) instead of a null pointer.
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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>
* 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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
* '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..
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>
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>
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>
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>
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>
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>
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>
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>
![](/avatar/5fc124e8ccd7b94d35e5c23f8c0b7c63?size=56 "\\\\"J. Bruce Fields\\\"){kind=small}
![](/avatar/511417582bfa18e9a88da2ada8339d64?size=56 "\\"Talpey, Thomas\"){kind=small}
