litmus-rt.git/mm, branch tracing-devel

Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block

2009-11-30T21:57:03+00:00

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  cciss: make device attrs static
  Thaw refrigerated bdi flusher threads before invoking kthread_stop on them

mm: allow memory hotplug and hibernation in the same kernel

2009-11-18T01:40:33+00:00

Allow memory hotplug and hibernation in the same kernel

Memory hotplug and hibernation were exclusive in Kconfig.  This is
obviously a problem for distribution kernels who want to support both in
the same image.

After some discussions with Rafael and others the only problem is with
parallel memory hotadd or removal while a hibernation operation is in
process.  It was also working for s390 before.

This patch removes the Kconfig level exclusion, and simply makes the
memory add / remove functions grab the pm_mutex to exclude against
hibernation.

Fixes a regression - old kernels didn't exclude memory hotadd and
hibernation.

Signed-off-by: Andi Kleen 
Cc: Gerald Schaefer 
Cc: KOSAKI Motohiro 
Cc: Yasunori Goto 
Acked-by: Rafael J. Wysocki 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memory_hotplug: fix section mismatch

2009-11-18T01:40:33+00:00

With CONFIG_MEMORY_HOTPLUG I got following warning:

WARNING: vmlinux.o(.text+0x1276b0): Section mismatch in reference from
the function hotadd_new_pgdat() to the function
.meminit.text:free_area_init_node()
The function hotadd_new_pgdat() references
the function __meminit free_area_init_node().
This is often because hotadd_new_pgdat lacks a __meminit
annotation or the annotation of free_area_init_node is wrong.

Use __ref to fix this.

Signed-off-by: Hidetoshi Seto 
Cc: Minchan Kim 
Cc: Mel Gorman 
Cc: Yasunori Goto 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu

2009-11-14T20:59:06+00:00

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: restructure pcpu_extend_area_map() to fix bugs and improve readability

percpu: restructure pcpu_extend_area_map() to fix bugs and improve readability

2009-11-12T15:55:35+00:00

pcpu_extend_area_map() had the following two bugs.

* It should return 1 if pcpu_lock was dropped and reacquired but it
  returned 0.  This could lead to oops if free_percpu() races with
  area map extension.

* pcpu_mem_free() was called under pcpu_lock.  pcpu_mem_free() might
  end up calling vfree() which isn't IRQ safe.  This could lead to
  deadlock through lock order inversion via IRQ.

In addition, Linus pointed out that the temporary lock dropping and
subtle three-way return value of pcpu_extend_area_map() was very ugly
and suggested to split the function into two - pcpu_need_to_extend()
and pcpu_extend_area_map().

This patch restructures pcpu_extend_area_map() as suggested and fixes
the two bugs.

Signed-off-by: Tejun Heo 
Acked-by: Linus Torvalds 
Cc: Ingo Molnar

memcg: fix wrong pointer initialization at page migration when memcg is disabled.

2009-11-12T15:25:56+00:00

Lee Schermerhorn reported that he saw bad pointer dereference in
mem_cgroup_end_migration() when he disabled memcg by boot option.

memcg's page migration logic works as

	mem_cgroup_prepare_migration(page, &ptr);
	do page migration
	mem_cgroup_end_migration(page, ptr);

Now, ptr is not initialized in prepare_migration when memcg is disabled
by boot option. This causes panic in end_migration. This patch fixes it.

Reported-by: Lee Schermerhorn 
Cc: Balbir Singh 
Signed-off-by: KAMEZAWA Hiroyuki 
Reviewed-by: Daisuke Nishimura 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

page allocator: Do not allow interrupts to use ALLOC_HARDER

2009-11-12T15:25:56+00:00

Commit 341ce06f69abfafa31b9468410a13dbd60e2b237 ("page allocator:
calculate the alloc_flags for allocation only once") altered watermark
logic slightly by allowing rt_tasks that are handling an interrupt to set
ALLOC_HARDER.  This patch brings the watermark logic more in line with
2.6.30.

This change results in a reduction of the number high-order GFP_ATOMIC
allocation failures reported.  See
http://www.gossamer-threads.com/lists/linux/kernel/1144153

[rientjes@google.com: Spotted the problem]
Signed-off-by: Mel Gorman 
Reviewed-by: Pekka Enberg 
Reviewed-by: Rik van Riel 
Reviewed-by: KOSAKI Motohiro 
Cc: David Rientjes 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

page allocator: always wake kswapd when restarting an allocation attempt after direct reclaim failed

2009-11-12T15:25:56+00:00

If a direct reclaim makes no forward progress, it considers whether it
should go OOM or not.  Whether OOM is triggered or not, it may retry the
allocation afterwards.  In times past, this would always wake kswapd as
well but currently, kswapd is not woken up after direct reclaim fails.
For order-0 allocations, this makes little difference but if there is a
heavy mix of higher-order allocations that direct reclaim is failing for,
it might mean that kswapd is not rewoken for higher orders as much as it
did previously.

This patch wakes up kswapd when an allocation is being retried after a
direct reclaim failure.  It would be expected that kswapd is already
awake, but this has the effect of telling kswapd to reclaim at the higher
order as well.

Signed-off-by: Mel Gorman 
Reviewed-by: Christoph Lameter 
Reviewed-by: Pekka Enberg 
Reviewed-by: KOSAKI Motohiro 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Thaw refrigerated bdi flusher threads before invoking kthread_stop on them

2009-11-12T12:08:11+00:00

Unfreezes the bdi flusher task when the said task needs to exit.

Steps to reproduce this.
1) Mount a file system from MMC/SD card.
2) Unmount the file system. This creates a flusher task.
3) Attempt suspend to RAM. System is unresponsive.

This is because the bdi flusher thread is already in the refrigerator and will
remain so until it is thawed. The MMC driver suspend routine call stack will
ultimately issue a 'kthread_stop' on the bdi flusher thread and will block
until the flusher thread is exited. Since the bdi flusher thread is in the
refrigerator it never cleans up until thawed.

Signed-off-by: Romit Dasgupta 
Signed-off-by: Jens Axboe

Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-11-11T19:30:15+00:00

* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  highmem: Fix debug_kmap_atomic() to also handle KM_IRQ_PTE, KM_NMI, and KM_NMI_PTE
  highmem: Fix race in debug_kmap_atomic() which could cause warn_count to underflow
  rcu: Fix long-grace-period race between forcing and initialization
  uids: Prevent tear down race