Some workloads really, really want to have no readahead.  Databases which are
perfoming small synchronous I/Os against a file which has extremely poor
layout.  Any readahead at all is a lose here.

But the current readahead code refuses to adapt that low.

Fix it up so that we can indeed adaptively disable readahead altogether, and
do not start it again until we have seen max_readahead()'s worth of
consecutive reads.

Patch from Trond Myklebust <trond.myklebust@fys.uio.no>

Implement sendfile() for the NFS client.  This is required for loop-on-NFS
support.

Tasks which throttle in balance_dirty_pages() will loop until the amount of
dirty memory falls below the configured dirty_ratio.

This exposes the possibility that one task could be stuck in there for
arbitrary periods of time due to page dirtying activity by other tasks.

The patch changes the logic so that tasks will break out of the loop if they
have written enough pages, regardless of the current dirty memory limits.

Here "enough" pages is 1.5x the number of pages which they just dirtied.

If the amount of dirty memory in the machine happens to still exceed
dirty_ratio (say, due to MAP_SHARED activity) then the task will again
throttle after dirtying a single page.  But there is now an upper limit on
the time for which a single task will be captured in balance_dirty_pages().

Patch from Andries.Brouwer@cwi.nl

The following patch does the following:

- static const char *blkdevs[MAX_BLKDEV]; disappears
- get_blkdev_list, (un)register_blkdev, __bdevname
  are moved from block_dev.c to genhd.c
- the third "fops" parameter of register_blkdev was unused;
  now removed everywhere
- zillions of places had printk("cannot get major") upon
  error return from register_blkdev; removed all of these
  and inserted a single printk in register_blkdev.

Of course the reason for the patch is that one fixed size
array is eliminated.

I'm getting a lot of cacheline bounce from .text.lock.file_table due to
false sharing of the cahceline. The following patch just aligns the lock
in it's own cacheline.

People keep asking for this info, and Andrew asked me to put it under the
Documentation directory ... provides really simple instructions for taking
a profile so that users can report performance changes in a useful way.

From Andy Whitcroft

Fix the type of get_zholes_size for NUMA-Q

From Andy Whitcroft

Convert physnode_map from an int to a u8 to save cachelines.

From Andy Whitcroft

A few very simple changes in order to make CONFIG_NUMA work everywhere, so
the distros can build one common binary kernel for distributions.

From Andy Whitcroft

Share a common physnode_map structure between NUMA-Q and Summit.

into home.transmeta.com:/home/torvalds/v2.5/linux

into home.transmeta.com:/home/torvalds/v2.5/linux

into home.transmeta.com:/home/torvalds/v2.5/linux

into kernel.bkbits.net:/home/davem/sparc-2.5

This is a minor cleanup.  We currently define and declare the BKL's
kernel_flag spinlock on either SMP or PREEMPT, which means a UP+PREEMPT
machine gets it.

We only need the actual lock on SMP.

into tp1.ruhr-uni-bochum.de:/scratch/kai/kernel/v2.5/linux-2.5.isdn

into nuts.ninka.net:/home/davem/src/BK/sparc-2.5

into penguin.transmeta.com:/home/penguin/torvalds/repositories/kernel/linux

This also shows how to add files to the initramfs build, but is 
commented out.

Patch originally done by Kai.

into penguin.transmeta.com:/home/penguin/torvalds/repositories/kernel/linux

Fix oops in getdfs when null path passed in on mount.  Fix oops when changed readsize caused readpages problem.  Add support for altering rsize so can reduce pages read across net
below default of 4

This fixes the SMP runqueue locking bug when updating the wakers
priority.  It also includes:

 - only update the priority and do a requeueing if the sleep average has
   changed. (this does not happen for pure CPU hogs or pure interactive
   tasks, so no need to requeue/recalc-prio in that case.) [All the
   necessary values are available at that point already, so gcc should
   have an easy job making this branch really cheap.]

 - do not do a full task activation in the migration-thread path - that is
   supposed to be near-atomic anyway.

 - fix up comments

I solved the SMP locking bug by moving the requeueing outside of
try_to_wake_up().  It does not matter that the priority update is not
atomically done now, since the current process wont do anything
inbetween.  (well, it could get preempted in a preemptible kernel, but
even that wont do any harm.)

The following messages are of interest only when debugging aio.
Otherwise, they are just console clutter.

- Remove broken lock accounting
- Introduce __locks_delete_block()
- Stop using kdevname()
- Fix locks_remove_posix()

 - fix a (now-) bug in kernel/softirq.c, it did a wakeup outside any
   atomic regions, which falsely identified random processes as a
   non-atomic wakeup, and which causes random priority boost to be
   distributed.

 - reset the initial idle thread's priority back to PRIO_MAX after doing
   the wakeup_forked_process() - correct preemption relies on this.

 - update current->prio immediately after a backboost.

 - clean up effective_prio() & sleep_avg calculations so that there are
   fewer RT-task special cases.  This has the advantage of the sleep_avg
   being maintained even for RT tasks - this could be advantegous for
   tasks that briefly enter/exit RT mode.

Seems there is a memleak on error exit path in drivers/char/vt.c, here's
the patch.  Found with help of smatch + enhanced unfree script.

__activate_task() and wake_up_forked_process() should call
nr_running_inc(rq) rather than doing a rq->nr_running++.

Noted by Rick Lindsley

The console initcall patch that went in contains a typo that prevents
alpha from building.

The stack reducing patch that recently went in prevent alpha from
building (missing some ELF_CORE_COPY_XFPREGS ifdefs). The excluded
patch fixes it.

This one simply sets TARGET_CPUS to cpu_callout_map instead of
cpu_online_map so that when we finally do boot we actually use the other
cpus for servicing interrupts.