Andrew Morton [Mon, 10 May 2004 06:30:22 +0000 (23:30 -0700)]
[PATCH] migration_thread() race fix
From: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Noticed that migration_thread can examine "kthread_should_stop()?" without
setting its state to TASK_INTERRUPTIBLE first. This can cause kthread_stop
on that thread to block forever ...
P.S - I assumed that having the task state set to TASK_INTERRUTIBLE
while it is doing active_load_balance is fine. It seemed to be
the case earlier also.
Andrew Morton [Mon, 10 May 2004 06:30:01 +0000 (23:30 -0700)]
[PATCH] Move migrate_all_tasks to CPU_DEAD handling
From: Srivatsa Vaddagiri <vatsa@in.ibm.com>
migrate_all_tasks is currently run with rest of the machine stopped.
It iterates thr' the complete task table, turning off cpu affinity of any task
that it finds affine to the dying cpu. Depending on the task table
size this can take considerable time. All this time machine is stopped, doing
nothing.
Stopping the machine for such extended periods can be avoided if we do
task migration in CPU_DEAD notification and that's precisely what this patch
does.
The patch puts idle task to the _front_ of the dying CPU's runqueue at the
highest priority possible. This cause idle thread to run _immediately_ after
kstopmachine thread yields. Idle thread notices that its cpu is offline and
dies quickly. Task migration can then be done at leisure in CPU_DEAD
notification, when rest of the CPUs are running.
Some advantages with this approach are:
- More scalable. Predicatable amout of time that machine is stopped.
- No changes to hot path/core code. We are just exploiting scheduler
rules which runs the next high-priority task on the runqueue. Also
since I put idle task to the _front_ of the runqueue, there
are no races when a equally high priority task is woken up
and added to the runqueue. It gets in at the back of the runqueue,
_after_ idle task!
- cpu_is_offline check that is presenty required in try_to_wake_up,
idle_balance and rebalance_tick can be removed, thus speeding them
up a bit
From: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Rusty mentioned that the unlikely hints against cpu_is_offline is
redundant since the macro already has that hint. Patch below removes those
redundant hints I added.
Andrew Morton [Mon, 10 May 2004 06:29:51 +0000 (23:29 -0700)]
[PATCH] sched: Look at another CPU's domain
From: Nick Piggin <nickpiggin@yahoo.com.au>
The SMT wake_idle code really wants to look at a non-local CPU's domain in
order to check for idle siblings.
So change the domain attachment code a little bit so we continue to hold a
runqueue's lock while attaching a new domain. This means the locking rules
have changed to: you may access your own domain without any lock, you must
hold a remote runqueue's lock in order to view its domain.
Andrew Morton [Mon, 10 May 2004 06:29:30 +0000 (23:29 -0700)]
[PATCH] sched: reduce idle time
From: Nick Piggin <nickpiggin@yahoo.com.au>
It makes NEWLY_IDLE balances cause find_busiest_group return the busiest
available group even if there isn't an imbalance. Basically - try a bit
harder to prevent schedule emptying the runqueue.
It is quite aggressive, but that isn't so bad because we don't (by default)
do NEWLY_IDLE balancing across NUMA nodes, and NEWLY_IDLE balancing is always
restricted to cache_hot tasks.
It picked up a little bit of idle time that dbt2-pgsql was seeing...
Andrew Morton [Mon, 10 May 2004 06:29:19 +0000 (23:29 -0700)]
[PATCH] sched: balance-on-clone
From: Ingo Molnar <mingo@elte.hu>
Implement balancing during clone(). It does the following things:
- introduces SD_BALANCE_CLONE that can serve as a tool for an
architecture to limit the search-idlest-CPU scope on clone().
E.g. the 512-CPU systems should rather not enable this.
- uses the highest sd for the imbalance_pct, not this_rq (which didnt
make sense).
- unifies balance-on-exec and balance-on-clone via the find_idlest_cpu()
function. Gets rid of sched_best_cpu() which was still a bit
inconsistent IMO, it used 'min_load < load' as a condition for
balancing - while a more correct approach would be to use half of the
imbalance_pct, like passive balancing does.
- the patch also reintroduces the possibility to do SD_BALANCE_EXEC on
SMP systems, and activates it - to get testing.
- NOTE: there's one thing in this patch that is slightly unclean: i
introduced wake_up_forked_thread. I did this to make it easier to get
rid of this patch later (wake_up_forked_process() has lots of
dependencies in various architectures). If this capability remains in
the kernel then i'll clean it up and introduce one function for
wake_up_forked_process/thread.
- NOTE2: i added the SD_BALANCE_CLONE flag to the NUMA CPU template too.
Some NUMA architectures probably want to disable this.
Andrew Morton [Mon, 10 May 2004 06:28:57 +0000 (23:28 -0700)]
[PATCH] sched: passive balancing damping
From: Nick Piggin <nickpiggin@yahoo.com.au>
This patch starts to balance woken processes when half the relevant domain's
imbalance_pct is reached. Previously balancing would start after a small,
constant difference in waker/wakee runqueue loads was reached, which would
cause too much process movement when there are lots of processes running.
It also turns wake balancing into a domain flag while previously it was always
on. Now sched domains can "soft partition" an SMP system without using
processor affinities.
Andrew Morton [Mon, 10 May 2004 06:28:20 +0000 (23:28 -0700)]
[PATCH] sched: extend sync wakeups
From: Ingo Molnar <mingo@elte.hu>
The attached patch extends sync wakeups to the process sys_exit() path too:
the chldwait wakeup can be done sync, since we know that the process is
going to exit (and thus deschedule).
The most visible effect of this change is strace's behavior on SMP systems:
it now stays on a single CPU, together with the traced child. (previously
it would run in parallel to the child, bouncing around madly.)
Andrew Morton [Mon, 10 May 2004 06:27:37 +0000 (23:27 -0700)]
[PATCH] sched: fix setup races
From: Nick Piggin <nickpiggin@yahoo.com.au>
De-racify the sched domain setup code. This involves creating a dummy
"init" domain during sched_init (which is called early).
When topology information becomes available, the sched domains are then
built and attached. The attach mechanism is asynchronous and uses the
migration threads, which perform the switch with interrupts off. This is a
quiescent state, so domains can still be lockless on the read side. It
also allows us to change the domains at runtime without much more work.
This is something SGI is interested in to elegantly do soft partitioning of
their systems without having to use hard cpu affinities (which cause
balancing problems of their own).
The current setup code also has a race somewhere because it is unable to
boot on a 384 CPU system.
From: Anton Blanchard <anton@samba.org>
This is basically a mindless ppc64 merge of the x86 changes to sched
domain init code.
Actually if I produce a sibling_map[] then the x86 code and the ppc64
will be identical. Maybe we can merge it.
Andrew Morton [Mon, 10 May 2004 06:27:13 +0000 (23:27 -0700)]
[PATCH] ppc64: sched-domain support
From: Anton Blanchard <anton@samba.org>
Below are the diffs between the current ppc64 sched init stuff and x86.
- Ignore the POWER5 specific stuff, I dont set up a sibling map yet.
- What should I set cache_hot_time to?
large cpumask typechecking requirements (perhaps useful on x86 as well):
- cpu->cpumask = CPU_MASK_NONE -> cpus_clear(cpu->cpumask);
- cpus_and(nodemask, node_to_cpumask(i), cpu_possible_map) doesnt work,
need to use a temporary
Andrew Morton [Mon, 10 May 2004 06:27:02 +0000 (23:27 -0700)]
[PATCH] sched: oops fix
From: Nick Piggin <nickpiggin@yahoo.com.au>
After the for_each_domain change, the warn here won't trigger, instead it
will oops in the if statement. Also, make sure we don't pass an empty
cpumask to for_each_cpu.
Andrew Morton [Mon, 10 May 2004 06:26:51 +0000 (23:26 -0700)]
[PATCH] sched: altix tuning
From: Nick Piggin <nickpiggin@yahoo.com.au>
From: John Hawkes
The following brings up performance on a 64-way Altix. This system being on
the smaller end of the scale should also be applicable to other NUMA systems.
Andrew Morton [Mon, 10 May 2004 06:26:30 +0000 (23:26 -0700)]
[PATCH] sched: wakeup balancing fixes
From: Nick Piggin <nickpiggin@yahoo.com.au>
Make affine wakes and "passive load balancing" more conservative. Aggressive
affine wakeups were causing huge regressions in dbt3-pgsql on 8-way non NUMA
systems at OSDL's STP.
Andrew Morton [Mon, 10 May 2004 06:26:19 +0000 (23:26 -0700)]
[PATCH] Hotplug CPU sched_balance_exec Fix
From: Rusty Russell <rusty@rustcorp.com.au>
From: Srivatsa Vaddagiri <vatsa@in.ibm.com>
From: Andrew Morton <akpm@osdl.org>
From: Rusty Russell <rusty@rustcorp.com.au>
We want to get rid of lock_cpu_hotplug() in sched_migrate_task. Found
that lockless migration of execing task is _extremely_ racy. The
races I hit are described below, alongwith probable solutions.
Task migration done elsewhere should be safe (?) since they either
hold the lock (sys_sched_setaffinity) or are done entirely with preemption
disabled (load_balance).
sched_balance_exec does:
a. disables preemption
b. finds new_cpu for current
c. enables preemption
d. calls sched_migrate_task to migrate current to new_cpu
and sched_migrate_task does:
e. task_rq_lock(p)
f. migrate_task(p, dest_cpu ..)
(if we have to wait for migration thread)
g. task_rq_unlock()
h. wake_up_process(rq->migration_thread)
i. wait_for_completion()
Several things can happen here:
1. new_cpu can go down after h and before migration thread has
got around to handle the request
==> we need to add a cpu_is_offline check in __migrate_task
2. new_cpu can go down between c and d or before f.
===> Even though this case is automatically handled by the above
change (migrate_task being called on a running task, current,
will delegate migration to migration thread), would it be
good practice to avoid calling migrate_task in the first place
itself when dest_cpu is offline. This means adding another
cpu_is_offline check after e in sched_migrate_task
3. The 'current' task can get preempted _immediately_ after
g and when it comes back, task_cpu(p) can be dead. In
which case, it is invalid to do wake_up on a non-existent migration
thread. (rq->migration_thread can be NULL).
===> We should disable preemption thr' g and h
4. Before migration thread gets around to handle the request, its cpu
goes dead. This will leave unhandled migration requests in the dead
cpu.
===> We need to wakeup sleeping requestors (if any) in CPU_DEAD
notification.
I really wonder if we can get rid of these issues by avoiding balancing at
exec time and instead have it balanced during load_balance ..Alternately
if this is valuable and we want to retain it, I think we still need to
consider a read/write sem, with sched_migrate_task doing down_read_trylock.
This may eliminate the deadlock I hit between cpu_up and CPU_UP_PREPARE
notification, which had forced me away from r/w sem.
Anyway patch below addresses the above races. Its against 2.6.6-rc2-mm1
and has been tested on a 4way Intel Pentium SMP m/c.
Rusty sez:
Two other changes:
1) I grabbed a reference to the thread, rather than using
preempt_disable(). It's the more obvious way I think.
2) Why the wait_to_die code? It might be needed if we move tasks after
stop_machine, but for nowI don't see the problem with the migration
thread running on the wrong CPU for a bit: nothing is on this runqueue
so active_load_balance is safe, and __migrate task will be a noop (due
to cpu_is_offline() check). If there is a problem, your fix is racy,
because we could be preempted immediately afterwards.
So I just stop the kthread then wakeup any remaining...
Andrew Morton [Mon, 10 May 2004 06:25:57 +0000 (23:25 -0700)]
[PATCH] Reduce TLB flushing during process migration
From: Martin Hicks <mort@wildopensource.com>
Another optimization patch from Jack Steiner, intended to reduce TLB
flushes during process migration.
Most architextures should define tlb_migrate_prepare() to be flush_tlb_mm(),
but on i386, it would be a wasted flush, because i386 disconnects previous
cpus from the tlb flush automatically.
Andrew Morton [Mon, 10 May 2004 06:25:45 +0000 (23:25 -0700)]
[PATCH] sched: add local load metrics
From: Nick Piggin <piggin@cyberone.com.au>
This patch removes the per runqueue array of NR_CPU arrays. Each time we
want to check a remote CPU's load we check nr_running as well anyway, so
introduce a cpu_load which is the load of the local runqueue and is kept
updated in the timer tick. Put them in the same cacheline.
This has additional benefits of having the cpu_load consistent across all
CPUs and more up to date. It is sampled better too, being updated once per
timer tick.
This shouldn't make much difference in scheduling behaviour, but all
benchmarks are either as good or better on the 16-way NUMAQ: hackbench,
reaim, volanomark are about the same, tbench and dbench are maybe a bit
better. kernbench is about one percent better.
John reckons it isn't a big deal, but it does save 4K per CPU or 2MB total
on his big systems, so I figure it must be a bit kinder on the caches. I
think it is just nicer in general anyway.
Andrew Morton [Mon, 10 May 2004 06:25:34 +0000 (23:25 -0700)]
[PATCH] sched: SMT niceness handling
From: Con Kolivas <kernel@kolivas.org>
This patch provides full per-package priority support for SMT processors
(aka pentium4 hyperthreading) when combined with CONFIG_SCHED_SMT.
It maintains cpu percentage distribution within each physical cpu package
by limiting the time a lower priority task can run on a sibling cpu
concurrently with a higher priority task.
It introduces a new flag into the scheduler domain
unsigned int per_cpu_gain; /* CPU % gained by adding domain cpus */
This is empirically set to 15% for pentium4 at the moment and can be
modified to support different values dynamically as newer processors come
out with improved SMT performance. It should not matter how many siblings
there are.
How it works is it compares tasks running on sibling cpus and when a lower
static priority task is running it will delay it till
high_priority_timeslice * (100 - per_cpu_gain) / 100 <= low_prio_timeslice
eg. a nice 19 task timeslice is 10ms and nice 0 timeslice is 102ms On
vanilla the nice 0 task runs on one logical cpu while the nice 19 task runs
unabated on the other logical cpu. With smtnice the nice 0 runs on one
logical cpu for 102ms and the nice 19 sleeps till the nice 0 task has 12ms
remaining and then will schedule.
Real time tasks and kernel threads are not altered by this code, and kernel
threads do not delay lower priority user tasks.
with lots of thanks to Zwane Mwaikambo and Nick Piggin for help with the
coding of this version.
If this is merged, it is probably best to delay pushing this upstream in
mainline till sched_domains gets tested for at least one major release.
Andrew Morton [Mon, 10 May 2004 06:25:11 +0000 (23:25 -0700)]
[PATCH] sched-group-power
From: Nick Piggin <piggin@cyberone.com.au>
The following patch implements a cpu_power member to struct sched_group.
This allows special casing to be removed for SMT groups in the balancing
code. It does not take CPU hotplug into account yet, but that shouldn't be
too hard.
I have tested it on the NUMAQ by pretending it has SMT. Works as expected.
Active balances across nodes.
Andrew Morton [Mon, 10 May 2004 06:25:00 +0000 (23:25 -0700)]
[PATCH] sched_balance_exec(): don't fiddle with the cpus_allowed mask
From: Rusty Russell <rusty@rustcorp.com.au>,
Nick Piggin <piggin@cyberone.com.au>
The current sched_balance_exec() sets the task's cpus_allowed mask
temporarily to move it to a different CPU. This has several issues,
including the fact that a task will see its affinity at a bogus value.
So we change the migration_req_t to explicitly specify a destination CPU,
rather than the migration thread deriving it from cpus_allowed. If the
requested CPU is no longer valid (racing with another set_cpus_allowed,
say), it can be ignored: if the task is not allowed on this CPU, there will
be another migration request pending.
This change allows sched_balance_exec() to tell the migration thread what
to do without changing the cpus_allowed mask.
So we rename __set_cpus_allowed() to move_task(), as the cpus_allowed mask
is now set by the caller. And move_task_away(), which the migration thread
uses to actually perform the move, is renamed __move_task().
I also ignore offline CPUs in sched_best_cpu(), so sched_migrate_task()
doesn't need to check for offline CPUs.
Ulterior motive: this approach also plays well with CPU Hotplug.
Previously that patch might have seen a task with cpus_allowed only
containing the dying CPU (temporarily due to sched_balance_exec) and
forcibly reset it to all cpus, which might be wrong. The other approach is
to hold the cpucontrol sem around sched_balance_exec(), which is too much
of a bottleneck.
Andrew Morton [Mon, 10 May 2004 06:24:49 +0000 (23:24 -0700)]
[PATCH] sched: handle inter-CPU jiffies skew
From: Nick Piggin <piggin@cyberone.com.au>
John Hawkes discribed this problem to me:
There *is* a small problem in this area, though, that SuSE avoids.
"jiffies" gets updated by cpu0. The other CPUs may, over time, get out of
sync (and they're initialized on ia64 to start out being out of sync), so
it's no guarantee that every CPU will wake up from its timer interrupt and
see a "jiffies" value that is guaranteed to be last_jiffies+1. Sometimes
the jiffies value may be unchanged since the last wakeup. Sometimes the
jiffies value may have incremented by 2 (or more, especially if cpu0's
interrupts are disabled for long stretches of time). So an algoithm that
says, "I'll call load_balance() only when jiffies is *exactly* N" is going
to fail on occasion, either by calling load_balance() too often or not
often enough. ***
I fixed this by adding a last_balance field to struct sched_domain, and
working off that.
Andrew Morton [Mon, 10 May 2004 06:24:38 +0000 (23:24 -0700)]
[PATCH] sched: implement domains for i386 HT
From: Nick Piggin <piggin@cyberone.com.au>
The following patch builds a scheduling description for the i386
architecture using cpu_sibling_map to set up SMT if CONFIG_SCHED_SMT is
set.
It could be made more fancy and collapse degenerate domains at runtime (ie.
1 sibling per CPU, or 1 NUMA node in the computer).
From: Zwane Mwaikambo <zwane@arm.linux.org.uk>
This fixes an oops due to cpu_sibling_map being uninitialised when a
system with no MP table (most UP boxen) boots a CONFIG_SMT kernel. What
also happens is that the cpu_group lists end up not being terminated
properly, but this oops kills it first. Patch tested on UP w/o MP table,
2x P2 and UP Xeon w/ no siblings.
From: "Martin J. Bligh" <mbligh@aracnet.com>,
Nick Piggin <piggin@cyberone.com.au>
Change arch_init_sched_domains to use cpu_online_map
Andrew Morton [Mon, 10 May 2004 06:24:26 +0000 (23:24 -0700)]
[PATCH] sched: cpu_sibling_map to cpu_mask
From: Nick Piggin <piggin@cyberone.com.au>
This is a (somewhat) trivial patch which converts cpu_sibling_map from an
array of CPUs to an array of cpumasks. Needed for >2 siblings per package,
but it actually can simplify code as it allows the cpu_sibling_map to be
set up even when there is 1 sibling per package. Intel want this, I use it
in the next patch to build scheduling domains for the P4 HT.
From: Thomas Schlichter <thomas.schlichter@web.de>
Andrew Morton [Mon, 10 May 2004 06:24:15 +0000 (23:24 -0700)]
[PATCH] scheduler domain balancing improvements
From: Nick Piggin <piggin@cyberone.com.au>
This patch gets the sched_domain scheduler working better WRT balancing.
Its been tested on the NUMAQ. Among other things it changes to the way SMT
load calculation works so as not to active load blances when it shouldn't.
It still has a problem with SMT and NUMA: it will put a task on each
sibling in a node before moving tasks to another node. It should probably
start moving tasks after each *physical* CPU is filled.
To fix, you need "how much CPU power in this domain?" At the moment we
approximate # runqueues == CPU power, and hack around it at the CPU
physical domain by counting all sibling runqueues as 1.
It isn't hard to correctly work the CPU power out, but once CPU hotplug is
in the equation it becomes much more hotplug events. If anyone is actually
interested in getting this fixed, that is.
Andrew Morton [Mon, 10 May 2004 06:23:54 +0000 (23:23 -0700)]
[PATCH] sched: scheduler domain support
From: Nick Piggin <piggin@cyberone.com.au>
This is the core sched domains patch. It can handle any number of levels
in a scheduling heirachy, and allows architectures to easily customize how
the scheduler behaves. It also provides progressive balancing backoff
needed by SGI on their large systems (although they have not yet tested
it).
It is built on top of (well, uses ideas from) my previous SMP/NUMA work, and
gets results very similar to them when using the default scheduling
description.
Benchmarks
==========
Martin was seeing I think 10-20% better system times in kernbench on the 32
way. I was seeing improvements in dbench, tbench, kernbench, reaim,
hackbench on a 16-way NUMAQ. Hackbench in fact had a non linear element
which is all but eliminated. Large improvements in volanomark.
Cross node task migration was decreased in all above benchmarks, sometimes by
a factor of 100!! Cross CPU migration was also generally decreased. See
this post:
http://groups.google.com.au/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&frame=right&th=a406c910b30cbac4&seekm=UAdQ.3hj.5%40gated-at.bofh.it#link2
Results on a hyperthreading P4 are equivalent to Ingo's shared runqueues
patch (which is a big improvement).
Some examples on the 16-way NUMAQ (this is slightly older sched domain code):
Tiny patch to make -mm3 compile on an NUMA box with NR_CPUS >
BITS_PER_LONG.
From: "Martin J. Bligh" <mbligh@aracnet.com>
Fix a minor nit with the find_busiest_group code. No functional change,
but makes the code simpler and clearer. This patch does two things ...
adds some more expansive comments, and removes this if clause:
Thus the if statement is redundant, and only makes the code harder to
read ;-)
From: Rick Lindsley <ricklind@us.ibm.com>
In find_busiest_group(), after we exit the do/while, we select our
imbalance. But max_load, avg_load, and this_load are all unsigned, so
min(x,y) will make a bad choice if max_load < avg_load < this_load (that
is, a choice between two negative [very large] numbers).
Unfortunately, there is a bug when max_load never gets changed from zero
(look in the loop and think what happens if the only load on the machine is
being created by cpu groups of which we are a member). And you have a
recipe for some really bogus values for imbalance.
Even if you fix the max_load == 0 bug, there will still be times when
avg_load - this_load will be negative (thus very large) and you'll make the
decision to move stuff when you shouldn't have.
This patch allows for this_load to set max_load, which if I understand
the logic properly is correct. With this patch applied, the algorithm is
*much* more conservative ... maybe *too* conservative but that's for
another round of testing ...
Andrew Morton [Mon, 10 May 2004 06:23:42 +0000 (23:23 -0700)]
[PATCH] sched: improved resolution in find_busiest_node
From: Nick Piggin <piggin@cyberone.com.au>
From: Frank Cornelis <frank.cornelis@elis.ugent.be>
In order to get the best possible resolution we need to use NR_CPUS instead
of the constant value 10. load is an int, so no need to worry about
overflows...
Linus Torvalds [Sun, 9 May 2004 11:43:07 +0000 (04:43 -0700)]
Mark the ACPI CPU throttle and timer IO regions busy.
This should help some laptops where the generic PCI
code might otherwise believe that this range is unused.
The ACPI IO range is usually not visible as a standard
BAR.
Andi Kleen [Sun, 9 May 2004 11:25:35 +0000 (04:25 -0700)]
[PATCH] Fix x86-64 compilation without iommu for 2.6.6rc3
Various people hit this in earlier kernels. The x86-64 kernel did not compile
without CONFIG_IOMMU_GART in various configurations. Just add the missing symbol
and export it. Also export iommu_merge while I am at it.
Andi Kleen [Sun, 9 May 2004 11:25:24 +0000 (04:25 -0700)]
[PATCH] Fix machine check handler on x86-64
This fixes a bug in the new machine check handler on x86-64.
One nasty part was that when you got an MCE during boot up
then it would not always print it on the screen, but still
panic because it attempted to kill the idle task.
This patch does:
- Always use KERN_EMERG when printing MCEs
- Always panic and print on screen before killing idle loop
or init.
Marc Singer [Sun, 9 May 2004 16:31:40 +0000 (17:31 +0100)]
[ARM PATCH] 1817/1: lh7a40x #2 (2/7) core-include
Patch from Marc Singer
Include files for this updated lh7a40x patch set. The changes in this
set from the previous are mostly cosmetic. The memory macros were
reworked in order to be more similar to the other ARM versions. The
previous versions produced the same results, but the forms are
slightly different.
Marc Singer [Sun, 9 May 2004 16:27:51 +0000 (17:27 +0100)]
[ARM PATCH] 1816/1: lh7a40x #2 (1/7) core
Patch from Marc Singer
Updated change set for the 2.6.5 kernel *and* for the April 8th arm
patch. Also included are changes suggested by Russell that merge
several of the files in the mach- directory. I have also endeavored
to remove all unnecessary whitespace additions.
Note that since I've found the cause of an annoying user-space crash,
I believe that this patch is OK. The crash appears to have nothing to
do with the system setup.
Tony Lindgren [Sun, 9 May 2004 11:56:38 +0000 (12:56 +0100)]
[ARM PATCH] 1847/1: OMAP update 2/2: include files
Patch from Tony Lindgren
This patch syncs the mainline kernel with the linux-omap tree. The
patch contains following updates:
- Move virtual IO area to 0xfefb0000 from 0xfffb0000 to fix parts of
IO area overlapping with ARM Linux reserved memory area
- Add support to OMAP-730, OMAP-5912, and OMAP-1710 processors
- Reorganize board support
- Add OMAP core detection
This patch requires ARM Linux patch 1844/1 be applied to compile
OMAP-730 and OMAP-5912
Tony Lindgren [Sun, 9 May 2004 11:52:15 +0000 (12:52 +0100)]
[ARM PATCH] 1846/1: OMAP update 1/2: arch files
Patch from Tony Lindgren
This patch syncs the mainline kernel with the linux-omap tree. The
patch contains following updates:
- Move virtual IO area to 0xfefb0000 from 0xfffb0000 to fix parts of
IO area overlapping with ARM Linux reserved memory area
- Add support to OMAP-730, OMAP-5912, and OMAP-1710 processors
- Reorganize board support
- Add OMAP core detection
This patch requires ARM Linux patch 1844/1 be applied to compile
OMAP-730 and OMAP-5912
Linus Torvalds [Sat, 8 May 2004 13:38:51 +0000 (06:38 -0700)]
Waste less memory in dentries.
We don't bother aligining them on a cacheline boundary, since
that is totally excessive in some configurations (especially
P4's with 128-byte cachelines).
Instead, we make the minimum inline string size a bit longer,
and re-order a few fields that allow for better packing on
64-bit architectures, for better memory utilization.
Andrew Morton [Sat, 8 May 2004 10:25:27 +0000 (03:25 -0700)]
[PATCH] run populate_rootfs() before initcalls
I moved this a little too late - we need to run populate_rootfs() before
running initcalls because some driver initcalls need to open files for
firmware.
The populate_rootfs() call is still coming after init_idle(), so it won't
knock the scheduler over.
This is a version of Binary Increase Control (BIC) TCP
developed by NCSU. It is yet another TCP congestion control
algorithm for handling big fat pipes. For normal size congestion
windows it behaves the same as existing TCP Reno, but when window
is large it uses additive increase to ensure fairness and when
window is small it uses binary search increase.
For more details see the BIC TCP web page
http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/
The original code was for web100 (2.4); this version is pretty
much the same but targeted for 2.6 with less sysctl parameters
and more constants.
I don't have a real high speed long haul network to test, but
when running over 1G links with delays, the performance is more stable
(ie tests are repeatable) and as fast as existing Reno.
[SCTP]: Fix multihomed connection failures on 64-bit systems.
Avoid the use of sizeof() and pointer arithmetic to get to the end
of sctp_cookie structure. Instead use the last element peer_init which
is a zero-sized array as the offset.
James Morris [Sat, 8 May 2004 08:05:57 +0000 (01:05 -0700)]
[NET]: Add sock_create_lite()
The purpose of this is to allow sockets created by the kernel in this way
to be passed through the LSM socket creation hooks and be labeled and
mediated in the same manner as other sockets.
This patches addresses a class of potential issues with LSMs, where such
sockets will not be labeled correctly (if at all), or mediated during
creation. Under SELinux, it fixes a specific bug where RPC sockets
created by the kernel during TCP NFS serving are unlabeled.
James Morris [Sat, 8 May 2004 08:00:33 +0000 (01:00 -0700)]
[NET]: Add sock_create_kern()
Under SELinux, and potentially other LSMs, we need to be able to
distinguish between user sockets and kernel sockets. For SELinux
specifically, kernel sockets need to be specially labeled during creation,
then bypass access control checks (they are controlled by the kernel
itself and not subject to SELinux mediation).
This addresses a class of potential issues in SELinux where, for example,
a TCP NFS session times out, then the kernel re-establishes an RPC
connection upon further user activity. We do not want such kernel
created sockets to be labeled with user security contexts.
sock_create() and sock_create_kern() are wrapper functions, which seems
semantically clearer to me than e.g. adding a flag to sock_create(). If
you prefer the latter, then let me know.
The patch also adds an argument to the LSM socket creation functions
indicating whether the socket being created is a kernel socket or not.
Andrew Morton [Sat, 8 May 2004 03:43:30 +0000 (20:43 -0700)]
[PATCH] fix WARN_ON on XFS module unload
From: Christoph Hellwig <hch@lst.de>
This one is a little funny. The SGI trees don't show this issue because dmapi
and quota are separate modules so they must be unloaded before xfs_fs_exit can
be called at all.
So let's move the exitcalls for them in mainline first to simulate that
behaviour.
This patch fixes a bug in the pmac-zilog driver where if you enable
CRTSCTS mode, it won't output data when CTS is asserted. On
powermacs, the CTS input is inverted. It also fixes a logic bug in
testing for CTS and DCD changes.
NTFS: 2.1.8 release - If the $LogFile indicates a clean shutdown and a
read-write (re)mount is requested, empty $LogFile by overwriting it
with 0xff bytes to ensure that Windows cannot cause data corruption
by replaying a stale journal after Linux has written to the volume.
NTFS: Read the journal ($LogFile) and determine if the volume has been shutdown cleanly
and force a read-only mount if not (fs/ntfs/super.c and fs/ntfs/logfile.c). This
is a little bit of a crude check in that we only look at the restart areas and
not at the actual log records so that there will be a very small number of cases
where we think that a volume is dirty when in fact it is clean. This should only
affect volumes that have not been shutdown cleanly and did not have any pending,
non-check-pointed i/o.
Stas Sergeev [Fri, 7 May 2004 02:35:35 +0000 (19:35 -0700)]
[PATCH] Fix IO bitmap invalidate
There is a bug where if any process that obtained an IO access
permissions via ioperm() does not explicitly "drop" that permissions,
the IO permissions don't get properly invalidated on process exit.
The cause is that exit_thread() only invalidates the per-thread
io_bitmap pointer, but doesn't invalidate the per-TSS io_bitmap pointer
as well.
As the per-thread pointer is invalidated, __switch_to() doesn't take
care of that one either, so the per-TSS pointer stays valid as long as
some other process does ioperm().
This fixes the problem - it invalidates the per-TSS io_bitmap pointer
and the problem goes away.
When Patrick removed ide_notify_reboot() in 2.5.42, he didn't notice
that it meant that IDE no longer had any shutdown() functionality.
So we did the right thing on suspend, but not on shutdown.
ide_notify_reboot() was only doing STANDBY on shutdown (because FLUSH
'doesn't work' in 2.4 too) but it worked okay and we still should do STANDBY
on shutdown because some broken disks flush their caches.
Thus just calls bus->suspend() (FLUSH+STANDBY) at shutdown time. We can
add some safety delay later - 2.4 doesn't have any.
I've updated the logips2pp driver to detect the MX310 and MX510 mice
and also made it more maintainable by putting everything into one
table instead of having 4 arrays for them (the MX700 support wasn't
added correctly in the last revision).
[PATCH] IDE disk cache flush at unopportune momemnts
This makes the idedisk_release function only flush the cache on final
release; with the recent 2.6 blocklayer updates release gets called
somewhat frequently, and at times where IO is outstanding to the disk.
This bug didn't trigger before simply because ide_cacheflush_p() always
was a nop.
Nitin A. Kamble [Thu, 6 May 2004 23:26:06 +0000 (16:26 -0700)]
[PATCH] mxcsr patch for i386 & x86-64
This enables proper mxcsr register masking: the magic mask "0xffbf"
is not necessarily correct for all CPU's, and there is an architected
way to discover the proper MXCSR feature bits by examining the fxsave
results.
Please refer to IA32 Software Developer's Manual, Volume 1, Section
11.6.6 for more details.
Petr Vandrovec [Thu, 6 May 2004 03:22:19 +0000 (20:22 -0700)]
[PATCH] ncpfs data corruption when using large TCP transfers
ncpfs was forgetting to update iovec's iov_base field whenever partial
transmission occured. This was causing data corruption during large
(60kB) writes.
The code now also passes copy of iovec to the sock_sendmsg, so it does
not rely on network stack updating (or not updating) passed iovec in
case of success (or failure).
Paul Wagland [Thu, 6 May 2004 00:50:40 +0000 (17:50 -0700)]
[PATCH] bug fix for megaraid memory leak
I was going through the code looking for bits and pieces to pull across
into the new LSI Logic beta megaraid driver /sys fs code and came across
this one.
LSI Logic have already fixed this issue for the 2.4 driver, and the new
beta driver does not use the /proc filesystem at all, so no problem
there.
The problem is that resources are not freed upon certain error
conditions in the in-kernel megaraid driver, to quote from Lester
Hightower (who originally found the issue):
"The problem occurs only in the circumstance where one reads one of
the /proc/megaraid/hba<X>/diskdrives-ch<N> files where the card <X>
does not have channel <N> on it. Most people would likely not
notice this leak in normal operation, but due to the way that we
monitor our MegaRaid cards in our company (we read these /proc
entries every 180s) so we found the leak rather quickly, and
unpleasantly (when your kernel eats all your RAM)."
Anyway, here is the fix, compiled and tested OK for me.
From: Alan Cox <alan@redhat.com>, Arjan van de Ven <arjanv@redhat.com>
- calculate drive->wcache for non-removable disks too
- flush the cache before unlocking the door on removable media,
otherwise you have a small race with the human
There is an bug in bigsmp sub-architecture, due to which it will not
enable all the CPUs when the BIOS-APICIDs are not 0 to n-1 (where n is
total number of CPUs). Particularly, only 2 CPU comes up on a system
that has 4 CPUs with BIOS APICID as (0, 1, 6, 7).=20
The bug is root caused to check_apicid_present(bit) call in smpboot.c,
when bigsmp is expecting apicid in place of bit.
check_apicid_present(bit) in bigsmp subarchitecture checks the bit with
phys_id_present_map (which is actually map representing all apicids and
not bit).
One solution is to change check_apicid_present(bit) to
check_apicid_present(apicid), in smp_boot_cpus(). But, it can affect
all the other subarchitectures in various subtle ways. So, here is a
simple alternate fix (Thanks to Martin Bligh), which solves the above
problem.
[ Confirmation from Martin:
Looks fine, it's exactly the same fix we use for Summit. Since
we're using the other method instead of the bitmap, this check
isn't needed, so we can just bypass it. This way also has the
great advantage of being isolated to the bigsmp subarch, so it only
needs testing there ;-)
]
Andrew Morton [Wed, 5 May 2004 09:46:18 +0000 (02:46 -0700)]
[PATCH] cciss update
From: <mikem@beardog.cca.cpqcorp.net>
This patch adds support for 2 new controllers. The first is a PCI-Express
version of the 6400. The second is actually a SATA controller using the cciss
interface.
projects / linux / log