setup_vmstat() registers its CPU notifier callback,
vmstat_cpuup_callback(), which marks N_CPU to a node when a CPU is put
into online. However, setup_vmstat() is called after all CPUs are
launched in the boot sequence.
Changed setup_vmstat() to mark N_CPU to the nodes with online CPUs at
boot, which is consistent with other operations in
vmstat_cpuup_callback(), i.e. start_cpu_timer() and
refresh_zone_stat_thresholds().
Also added get_online_cpus() to protect the for_each_online_cpu() loop.
Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Christoph Lameter <cl@linux.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tang Chen [Tue, 5 Nov 2013 05:55:51 +0000 (16:55 +1100)]
mem-hotplug: introduce movable_node boot option
The hot-Pluggable field in SRAT specifies which memory is hotpluggable.
As we mentioned before, if hotpluggable memory is used by the kernel, it
cannot be hot-removed. So memory hotplug users may want to set all
hotpluggable memory in ZONE_MOVABLE so that the kernel won't use it.
Memory hotplug users may also set a node as movable node, which has
ZONE_MOVABLE only, so that the whole node can be hot-removed.
But the kernel cannot use memory in ZONE_MOVABLE. By doing this, the
kernel cannot use memory in movable nodes. This will cause NUMA
performance down. And other users may be unhappy.
So we need a way to allow users to enable and disable this functionality.
In this patch, we introduce movable_node boot option to allow users to
choose to not to consume hotpluggable memory at early boot time and later
we can set it as ZONE_MOVABLE.
To achieve this, the movable_node boot option will control the memblock
allocation direction. That said, after memblock is ready, before SRAT is
parsed, we should allocate memory near the kernel image as we explained in
the previous patches. So if movable_node boot option is set, the kernel
does the following:
1. After memblock is ready, make memblock allocate memory bottom up.
2. After SRAT is parsed, make memblock behave as default, allocate memory
top down.
Users can specify "movable_node" in kernel commandline to enable this
functionality. For those who don't use memory hotplug or who don't want
to lose their NUMA performance, just don't specify anything. The kernel
will work as before.
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Suggested-by: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Suggested-by: Ingo Molnar <mingo@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Thomas Renninger <trenn@suse.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tang Chen [Tue, 5 Nov 2013 05:55:51 +0000 (16:55 +1100)]
x86, acpi, crash, kdump: do reserve_crashkernel() after SRAT is parsed.
Memory reserved for crashkernel could be large. So we should not allocate
this memory bottom up from the end of kernel image.
When SRAT is parsed, we will be able to know which memory is hotpluggable,
and we can avoid allocating this memory for the kernel. So reorder
reserve_crashkernel() after SRAT is parsed.
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Thomas Renninger <trenn@suse.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tang Chen [Tue, 5 Nov 2013 05:55:50 +0000 (16:55 +1100)]
x86/mem-hotplug: support initialize page tables in bottom-up
The Linux kernel cannot migrate pages used by the kernel. As a result,
kernel pages cannot be hot-removed. So we cannot allocate hotpluggable
memory for the kernel.
In a memory hotplug system, any numa node the kernel resides in should be
unhotpluggable. And for a modern server, each node could have at least
16GB memory. So memory around the kernel image is highly likely
unhotpluggable.
ACPI SRAT (System Resource Affinity Table) contains the memory hotplug
info. But before SRAT is parsed, memblock has already started to allocate
memory for the kernel. So we need to prevent memblock from doing this.
So direct memory mapping page tables setup is the case.
init_mem_mapping() is called before SRAT is parsed. To prevent page
tables being allocated within hotpluggable memory, we will use bottom-up
direction to allocate page tables from the end of kernel image to the
higher memory.
Note:
As for allocating page tables in lower memory, TJ said:
: This is an optional behavior which is triggered by a very specific kernel
: boot param, which I suspect is gonna need to stick around to support
: memory hotplug in the current setup unless we add another layer of address
: translation to support memory hotplug.
As for page tables may occupy too much lower memory if using 4K mapping
(CONFIG_DEBUG_PAGEALLOC and CONFIG_KMEMCHECK both disable using >4k
pages), TJ said:
: But as I said in the same paragraph, parsing SRAT earlier doesn't solve
: the problem in itself either. Ignoring the option if 4k mapping is
: required and memory consumption would be prohibitive should work, no?
: Something like that would be necessary if we're gonna worry about cases
: like this no matter how we implement it, but, frankly, I'm not sure this
: is something worth worrying about.
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Thomas Renninger <trenn@suse.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tang Chen [Tue, 5 Nov 2013 05:55:49 +0000 (16:55 +1100)]
x86/mm: factor out of top-down direct mapping setup
Create a new function memory_map_top_down to factor out of the top-down
direct memory mapping pagetable setup. This is also a preparation for the
following patch, which will introduce the bottom-up memory mapping. That
said, we will put the two ways of pagetable setup into separate functions,
and choose to use which way in init_mem_mapping, which makes the code more
clear.
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Thomas Renninger <trenn@suse.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The Linux kernel cannot migrate pages used by the kernel. As a result,
kernel pages cannot be hot-removed. So we cannot allocate hotpluggable
memory for the kernel.
ACPI SRAT (System Resource Affinity Table) contains the memory hotplug
info. But before SRAT is parsed, memblock has already started to allocate
memory for the kernel. So we need to prevent memblock from doing this.
In a memory hotplug system, any numa node the kernel resides in should be
unhotpluggable. And for a modern server, each node could have at least
16GB memory. So memory around the kernel image is highly likely
unhotpluggable.
So the basic idea is: Allocate memory from the end of the kernel image and
to the higher memory. Since memory allocation before SRAT is parsed won't
be too much, it could highly likely be in the same node with kernel image.
The current memblock can only allocate memory top-down. So this patch
introduces a new bottom-up allocation mode to allocate memory bottom-up.
And later when we use this allocation direction to allocate memory, we
will limit the start address above the kernel.
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Tejun Heo <tj@kernel.org> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Thomas Renninger <trenn@suse.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tang Chen [Tue, 5 Nov 2013 05:55:48 +0000 (16:55 +1100)]
mm/memblock.c: factor out of top-down allocation
[Problem]
The current Linux cannot migrate pages used by the kernel because of the
kernel direct mapping. In Linux kernel space, va = pa + PAGE_OFFSET.
When the pa is changed, we cannot simply update the pagetable and keep the
va unmodified. So the kernel pages are not migratable.
There are also some other issues will cause the kernel pages not
migratable. For example, the physical address may be cached somewhere and
will be used. It is not to update all the caches.
When doing memory hotplug in Linux, we first migrate all the pages in one
memory device somewhere else, and then remove the device. But if pages
are used by the kernel, they are not migratable. As a result, memory used
by the kernel cannot be hot-removed.
Modifying the kernel direct mapping mechanism is too difficult to do. And
it may cause the kernel performance down and unstable. So we use the
following way to do memory hotplug.
[What we are doing]
In Linux, memory in one numa node is divided into several zones. One of
the zones is ZONE_MOVABLE, which the kernel won't use.
In order to implement memory hotplug in Linux, we are going to arrange all
hotpluggable memory in ZONE_MOVABLE so that the kernel won't use these
memory. To do this, we need ACPI's help.
In ACPI, SRAT(System Resource Affinity Table) contains NUMA info. The
memory affinities in SRAT record every memory range in the system, and
also, flags specifying if the memory range is hotpluggable. (Please refer
to ACPI spec 5.0 5.2.16)
With the help of SRAT, we have to do the following two things to achieve our
goal:
1. When doing memory hot-add, allow the users arranging hotpluggable as
ZONE_MOVABLE.
(This has been done by the MOVABLE_NODE functionality in Linux.)
2. when the system is booting, prevent bootmem allocator from allocating
hotpluggable memory for the kernel before the memory initialization
finishes.
The problem 2 is the key problem we are going to solve. But before solving it,
we need some preparation. Please see below.
[Preparation]
Bootloader has to load the kernel image into memory. And this memory must
be unhotpluggable. We cannot prevent this anyway. So in a memory hotplug
system, we can assume any node the kernel resides in is not hotpluggable.
Before SRAT is parsed, we don't know which memory ranges are hotpluggable.
But memblock has already started to work. In the current kernel,
memblock allocates the following memory before SRAT is parsed:
setup_arch()
|->memblock_x86_fill() /* memblock is ready */
|......
|->early_reserve_e820_mpc_new() /* allocate memory under 1MB */
|->reserve_real_mode() /* allocate memory under 1MB */
|->init_mem_mapping() /* allocate page tables, about 2MB to map 1GB memory */
|->dma_contiguous_reserve() /* specified by user, should be low */
|->setup_log_buf() /* specified by user, several mega bytes */
|->relocate_initrd() /* could be large, but will be freed after boot, should reorder */
|->acpi_initrd_override() /* several mega bytes */
|->reserve_crashkernel() /* could be large, should reorder */
|......
|->initmem_init() /* Parse SRAT */
According to Tejun's advice, before SRAT is parsed, we should try our best
to allocate memory near the kernel image. Since the whole node the kernel
resides in won't be hotpluggable, and for a modern server, a node may have
at least 16GB memory, allocating several mega bytes memory around the
kernel image won't cross to hotpluggable memory.
[About this patchset]
So this patchset is the preparation for the problem 2 that we want to
solve. It does the following:
1. Make memblock be able to allocate memory bottom up.
1) Keep all the memblock APIs' prototype unmodified.
2) When the direction is bottom up, keep the start address greater than the
end of kernel image.
2. Improve init_mem_mapping() to support allocate page tables in
bottom up direction.
3. Introduce "movable_node" boot option to enable and disable this
functionality.
This patch (of 6):
Create a new function __memblock_find_range_top_down to factor out of
top-down allocation from memblock_find_in_range_node. This is a
preparation because we will introduce a new bottom-up allocation mode in
the following patch.
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Thomas Renninger <trenn@suse.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
swap: fix setting PAGE_SIZE blocksize during swapoff/swapon race
Fix race between swapoff and swapon resulting in setting blocksize of
PAGE_SIZE for block devices during swapoff.
The swapon modifies swap_info->old_block_size before acquiring
swapon_mutex. It reads block_size of bdev, stores it under
swap_info->old_block_size and sets new block_size to PAGE_SIZE.
On the other hand the swapoff sets the device's block_size to
old_block_size after releasing swapon_mutex.
This patch locks the swapon_mutex much earlier during swapon. It also
releases the swapon_mutex later during swapoff.
The effect of race can be triggered by following scenario:
- One block swap device with block size of 512
- thread 1: Swapon is called, swap is activated,
p->old_block_size = block_size(p->bdev); /512/
block_size(p->bdev) = PAGE_SIZE;
Thread ends.
- thread 2: Swapoff is called and it goes just after releasing the
swapon_mutex. The swap is now fully disabled except of setting the
block size to old value. The p->bdev->block_size is still equal to
PAGE_SIZE.
- thread 3: New swapon is called. This swap is disabled so without
acquiring the swapon_mutex:
- p->old_block_size = block_size(p->bdev); /PAGE_SIZE (!!!)/
- block_size(p->bdev) = PAGE_SIZE;
Swap is activated and thread ends.
- thread 2: resumes work and sets blocksize to old value:
- set_blocksize(bdev, p->old_block_size)
But now the p->old_block_size is equal to PAGE_SIZE.
The patch swap-fix-set_blocksize-race-during-swapon-swapoff does not fix
this particular issue. It reduces the possibility of races as the swapon
must overwrite p->old_block_size before acquiring swapon_mutex in swapoff.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Cc: Weijie Yang <weijie.yang.kh@gmail.com> Cc: Bob Liu <bob.liu@oracle.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Shaohua Li <shli@fusionio.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Heiko Carstens [Tue, 5 Nov 2013 05:55:47 +0000 (16:55 +1100)]
s390/mmap: randomize mmap base for bottom up direction
Implement mmap base randomization for the bottom up direction, so ASLR
works for both mmap layouts on s390. See also df54d6fa54 ("x86
get_unmapped_area(): use proper mmap base for bottom-up direction").
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Radu Caragea <sinaelgl@gmail.com> Cc: Michel Lespinasse <walken@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Heiko Carstens [Tue, 5 Nov 2013 05:55:47 +0000 (16:55 +1100)]
mmap: arch_get_unmapped_area(): use proper mmap base for bottom up direction
This is more or less the generic variant of 41aacc1eea ("x86
get_unmapped_area: Access mmap_legacy_base through mm_struct member").
So effectively architectures which use an own arch_pick_mmap_layout()
implementation but call the generic arch_get_unmapped_area() now can also
randomize their mmap_base.
All architectures which have an own arch_pick_mmap_layout() and call the
generic arch_get_unmapped_area() (arm64, s390, tile) currently set
mmap_base to TASK_UNMAPPED_BASE. This is also true for the generic
arch_pick_mmap_layout() function. So this change is a no-op currently.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Radu Caragea <sinaelgl@gmail.com> Cc: Michel Lespinasse <walken@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Weijie Yang [Tue, 5 Nov 2013 05:55:46 +0000 (16:55 +1100)]
mm/zswap: avoid unnecessary page scanning
Add SetPageReclaim() before __swap_writepage() so that page can be moved
to the tail of the inactive list, which can avoid unnecessary page
scanning as this page was reclaimed by swap subsystem before.
Signed-off-by: Weijie Yang <weijie.yang@samsung.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Reviewed-by: Minchan Kim <minchan@kernel.org> Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
On Wed 09-10-13 14:21:25, Andrew Morton wrote:
> On Wed, 9 Oct 2013 17:03:25 +0200 Jan Kara <jack@suse.cz> wrote:
>
> > From: Jan Kara <jack@suse.cz>
> > Date: Wed, 9 Oct 2013 15:41:50 +0200
> > Subject: [PATCH] writeback: Use older_than_this_is_set instead of magic
> > older_than_this == 0
> >
> > Currently we use 0 as a special value of work->older_than_this to
> > indicate that wb_writeback() should set work->older_that_this to current
> > time. This works but it is a bit magic. So use a special flag in
> > work_struct for that.
>
> OK.
>
> > - if (!work->older_than_this)
> > + if (!work->older_than_this_is_set)
> > work->older_than_this = jiffies;
>
> It would be logical although presumably unneeded to set
> older_than_this_is_set here?
Yes. Updated.
> > Also fixup writeback from workqueue rescuer to include all inodes.
>
> There's nothing in the patch which matches this sentence?
The sentence is about the hunk below. writeback_inodes_wb() is special in
that it directly calls queue_io() (everything else goes through
wb_writeback()) and my previous patch thus resulted in using 0 as an
older_than_this value => likely we wouldn't queue any inodes for writeback.
I've added WARN_ON_ONCE into move_expired_inodes() to increase a chance of
catching such mistakes in future (although in this particular case it
wouldn't really help because writeback_inodes_wb() gets hardly ever
called).
Currently we use 0 as a special value of work->older_than_this to
indicate that wb_writeback() should set work->older_that_this to current
time. This works but it is a bit magic. So use a special flag in
work_struct for that.
Also fixup writeback from workqueue rescuer (writeback_inodes_wb()) to
include all inodes. Currently it would use 0 as an older_than_this value
thus queue_io() would likely not queue any inodes for writeback.
Signed-off-by: Jan Kara <jack@suse.cz> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Dave Chinner <dchinner@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jan Kara [Tue, 5 Nov 2013 05:55:45 +0000 (16:55 +1100)]
writeback: use older_than_this_is_set instead of magic older_than_this == 0
Currently we use 0 as a special value of work->older_than_this to
indicate that wb_writeback() should set work->older_that_this to current
time. This works but it is a bit magic. So use a special flag in
work_struct for that.
Also fixup writeback from workqueue rescuer to include all inodes.
Signed-off-by: Jan Kara <jack@suse.cz> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Dave Chinner <dchinner@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jan Kara [Tue, 5 Nov 2013 05:55:44 +0000 (16:55 +1100)]
writeback: do not sync data dirtied after sync start
When there are processes heavily creating small files while sync(2) is
running, it can easily happen that quite some new files are created
between WB_SYNC_NONE and WB_SYNC_ALL pass of sync(2). That can happen
especially if there are several busy filesystems (remember that sync
traverses filesystems sequentially and waits in WB_SYNC_ALL phase on one
fs before starting it on another fs). Because WB_SYNC_ALL pass is slow
(e.g. causes a transaction commit and cache flush for each inode in
ext3), resulting sync(2) times are rather large.
The following script reproduces the problem:
function run_writers
{
for (( i = 0; i < 10; i++ )); do
mkdir $1/dir$i
for (( j = 0; j < 40000; j++ )); do
dd if=/dev/zero of=$1/dir$i/$j bs=4k count=4 &>/dev/null
done &
done
}
for dir in "$@"; do
run_writers $dir
done
sleep 40
time sync
======
Fix the problem by disregarding inodes dirtied after sync(2) was called in
the WB_SYNC_ALL pass. To allow for this, sync_inodes_sb() now takes a
time stamp when sync has started which is used for setting up work for
flusher threads.
To give some numbers, when above script is run on two ext4 filesystems on
simple SATA drive, the average sync time from 10 runs is 267.549 seconds
with standard deviation 104.799426. With the patched kernel, the average
sync time from 10 runs is 2.995 seconds with standard deviation 0.096.
Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Fengguang Wu <fengguang.wu@intel.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Naoya Horiguchi [Tue, 5 Nov 2013 05:55:43 +0000 (16:55 +1100)]
tools/vm/page-types.c: support KPF_SOFTDIRTY bit
Soft dirty bit allows us to track which pages are written since the last
clear_ref (by "echo 4 > /proc/pid/clear_refs".) This is useful for
userspace applications to know their memory footprints.
Note that the kernel exposes this flag via bit[55] of /proc/pid/pagemap,
and the semantics is not a default one (scheduled to be the default in the
near future.) However, it shifts to the new semantics at the first
clear_ref, and the users of soft dirty bit always do it before utilizing
the bit, so that's not a big deal. Users must avoid relying on the bit in
page-types before the first clear_ref.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
frontswap: enable call to invalidate area on swapoff
During swapoff the frontswap_map was NULL-ified before calling
frontswap_invalidate_area(). However the frontswap_invalidate_area()
exits early if frontswap_map is NULL. Invalidate was never called during
swapoff.
This patch moves frontswap_map_set() in swapoff just after calling
frontswap_invalidate_area() so outside of locks (swap_lock and
swap_info_struct->lock). This shouldn't be a problem as during swapon the
frontswap_map_set() is called also outside of any locks.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Reviewed-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Shaohua Li <shli@fusionio.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Catalin Marinas [Tue, 5 Nov 2013 05:55:40 +0000 (16:55 +1100)]
mm: kmemleak: avoid false negatives on vmalloc'ed objects
Commit 248ac0e1 ("mm/vmalloc: remove guard page from between vmap blocks")
had the side effect of making vmap_area.va_end member point to the next
vmap_area.va_start. This was creating an artificial reference to
vmalloc'ed objects and kmemleak was rarely reporting vmalloc() leaks.
This patch marks the vmap_area containing pointers explicitly and reduces
the min ref_count to 2 as vm_struct still contains a reference to the
vmalloc'ed object. The kmemleak add_scan_area() function has been
improved to allow a SIZE_MAX argument covering the rest of the object (for
simpler calling sites).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Zhang Yanfei [Tue, 5 Nov 2013 05:55:39 +0000 (16:55 +1100)]
mm/sparsemem: fix a bug in free_map_bootmem when CONFIG_SPARSEMEM_VMEMMAP
We pass the number of pages which hold page structs of a memory section to
free_map_bootmem(). This is right when !CONFIG_SPARSEMEM_VMEMMAP but
wrong when CONFIG_SPARSEMEM_VMEMMAP. When CONFIG_SPARSEMEM_VMEMMAP, we
should pass the number of pages of a memory section to free_map_bootmem.
So the fix is removing the nr_pages parameter. When
CONFIG_SPARSEMEM_VMEMMAP, we directly use the prefined marco
PAGES_PER_SECTION in free_map_bootmem. When !CONFIG_SPARSEMEM_VMEMMAP, we
calculate page numbers needed to hold the page structs for a memory
section and use the value in free_map_bootmem().
This was found by reading the code. And I have no machine that support
memory hot-remove to test the bug now.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Andy Whitcroft <apw@shadowen.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
they are always invoked to operate on one memory section, so it is
redundant to always pass a nr_pages parameter, which is the page numbers
in one section. So we can directly use predefined macro PAGES_PER_SECTION
instead of passing the parameter.
Ying Han [Tue, 5 Nov 2013 05:55:38 +0000 (16:55 +1100)]
memcg: support hierarchical memory.numa_stats
The memory.numa_stat file was not hierarchical. Memory charged to the
children was not shown in parent's numa_stat.
This change adds the "hierarchical_" stats to the existing stats. The new
hierarchical stats include the sum of all children's values in addition to
the value of the memcg.
Tested: Create cgroup a, a/b and run workload under b. The values of
b are included in the "hierarchical_*" under a.
$ cd /sys/fs/cgroup
$ echo 1 > memory.use_hierarchy
$ mkdir a a/b
Run workload in a/b:
$ (echo $BASHPID >> a/b/cgroup.procs && cat /some/file && bash) &
The hierarchical_ fields in parent (a) show use of workload in a/b:
$ cat a/memory.numa_stat
total=0 N0=0 N1=0 N2=0 N3=0
file=0 N0=0 N1=0 N2=0 N3=0
anon=0 N0=0 N1=0 N2=0 N3=0
unevictable=0 N0=0 N1=0 N2=0 N3=0
hierarchical_total=908 N0=552 N1=317 N2=39 N3=0
hierarchical_file=850 N0=549 N1=301 N2=0 N3=0
hierarchical_anon=58 N0=3 N1=16 N2=39 N3=0
hierarchical_unevictable=0 N0=0 N1=0 N2=0 N3=0
Signed-off-by: Ying Han <yinghan@google.com> Signed-off-by: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Greg Thelen [Tue, 5 Nov 2013 05:55:37 +0000 (16:55 +1100)]
memcg: refactor mem_control_numa_stat_show()
Refactor mem_control_numa_stat_show() to use a new stats structure for
smaller and simpler code. This consolidates nearly identical code.
text data bss dec hex filename
8,137,679 1,703,496 1,896,448 11,737,623 b31a17 vmlinux.before
8,136,911 1,703,496 1,896,448 11,736,855 b31717 vmlinux.after
Signed-off-by: Greg Thelen <gthelen@google.com> Signed-off-by: Ying Han <yinghan@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
make last_khugepaged_target_node local to khugepaged_find_target_node()
Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andrew Davidoff <davidoff@qedmf.net> Cc: Bob Liu <bob.liu@oracle.com> Cc: Bob Liu <lliubbo@gmail.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bob Liu [Tue, 5 Nov 2013 05:55:36 +0000 (16:55 +1100)]
mm: thp: khugepaged: add policy for finding target node
Khugepaged will scan/free HPAGE_PMD_NR normal pages and replace with a
hugepage which is allocated from the node of the first scanned normal
page, but this policy is too rough and may end with unexpected result to
upper users.
The problem is the original page-balancing among all nodes will be broken
after hugepaged started. Thinking about the case if the first scanned
normal page is allocated from node A, most of other scanned normal pages
are allocated from node B or C.. But hugepaged will always allocate
hugepage from node A which will cause extra memory pressure on node A
which is not the situation before khugepaged started.
This patch try to fix this problem by making khugepaged allocate hugepage
from the node which have max record of scaned normal pages hit, so that
the effect to original page-balancing can be minimized.
The other problem is if normal scanned pages are equally allocated from
Node A,B and C, after khugepaged started Node A will still suffer extra
memory pressure.
Andrew Davidoff reported a related issue several days ago. He wanted his
application interleaving among all nodes and "numactl --interleave=all
./test" was used to run the testcase, but the result wasn't not as
expected.
cat /proc/2814/numa_maps: 7f50bd440000 interleave:0-3 anon=51403 dirty=51403 N0=435 N1=435 N2=435
N3=50098
The end result showed that most pages are from Node3 instead of interleave
among node0-3 which was unreasonable.
This patch also fix this issue by allocating hugepage round robin from all
nodes have the same record, after this patch the result was as expected: 7f78399c0000 interleave:0-3 anon=51403 dirty=51403 N0=12723 N1=12723
N2=13235 N3=12722
The simple testcase is like this:
int main() {
char *p;
int i;
int j;
for (i=0; i < 200; i++) {
p = (char *)malloc(1048576);
printf("malloc done\n");
if (p == 0) {
printf("Out of memory\n");
return 1;
}
for (j=0; j < 1048576; j++) {
p[j] = 'A';
}
printf("touched memory\n");
Reported-by: Andrew Davidoff <davidoff@qedmf.net> Tested-by: Andrew Davidoff <davidoff@qedmf.net> Signed-off-by: Bob Liu <bob.liu@oracle.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bob Liu [Tue, 5 Nov 2013 05:55:35 +0000 (16:55 +1100)]
mm: thp: cleanup: mv alloc_hugepage to better place
Move alloc_hugepage() to a better place, no need for a seperate #ifndef
CONFIG_NUMA
Signed-off-by: Bob Liu <bob.liu@oracle.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Andrew Davidoff <davidoff@qedmf.net> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Wanpeng Li [Tue, 5 Nov 2013 05:55:34 +0000 (16:55 +1100)]
revert mm/vmalloc.c: emit the failure message before return
Don't warn twice in __vmalloc_area_node and __vmalloc_node_range if
__vmalloc_area_node allocation failure. This patch reverts commit 46c001a2 ("mm/vmalloc.c: emit the failure message before return").
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Wanpeng Li [Tue, 5 Nov 2013 05:55:34 +0000 (16:55 +1100)]
mm/vmalloc: revert "mm/vmalloc.c: check VM_UNINITIALIZED flag in s_show instead of show_numa_info"
The VM_UNINITIALIZED/VM_UNLIST flag introduced by f5252e00 ("mm:
avoid null pointer access in vm_struct via /proc/vmallocinfo") is used to
avoid accessing the pages field with unallocated page when
show_numa_info() is called. This patch move the check just before
show_numa_info in order that some messages still can be dumped via
/proc/vmallocinfo. This patch revert commit d157a558 ("mm/vmalloc.c: check
VM_UNINITIALIZED flag in s_show instead of show_numa_info");
Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The assumption !VM_VM_AREA represents vm_map_ram allocation is introduced
by d4033afd ("mm, vmalloc: iterate vmap_area_list, instead of vmlist, in
vmallocinfo()"). However, !VM_VM_AREA also represents vmap_area is being
tear down in race window mentioned above. This patch fix it by don't dump
any information for !VM_VM_AREA case and also remove (VM_LAZY_FREE |
VM_LAZY_FREEING) check since they are not possible for !VM_VM_AREA case.
Suggested-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
David Rientjes [Tue, 5 Nov 2013 05:55:32 +0000 (16:55 +1100)]
mm, mempolicy: make mpol_to_str robust and always succeed
mpol_to_str() should not fail. Currently, it either fails because the
string buffer is too small or because a string hasn't been defined for a
mempolicy mode.
If a new mempolicy mode is introduced and no string is defined for it,
just warn and return "unknown".
If the buffer is too small, just truncate the string and return, the same
behavior as snprintf().
This also fixes a bug where there was no NULL-byte termination when doing
*p++ = '=' and *p++ ':' and maxlen has been reached.
Signed-off-by: David Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Chen Gang <gang.chen@asianux.com> Cc: Rik van Riel <riel@redhat.com> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Chen Gong pointed out that set/unset_migratetype_isolate() was done in
different functions in mm/memory-failure.c, which makes the code less
readable/maintainable. So this patch does it in soft_offline_page().
With this patch, we get to hold lock_memory_hotplug() longer but it's not
a problem because races between memory hotplug and soft offline are very
rare.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Chen, Gong <gong.chen@linux.intel.com> Acked-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Toshi Kani [Tue, 5 Nov 2013 05:55:30 +0000 (16:55 +1100)]
cpu/mem hotplug: add try_online_node() for cpu_up()
cpu_up() has #ifdef CONFIG_MEMORY_HOTPLUG code blocks, which call
mem_online_node() to put its node online if offlined and then call
build_all_zonelists() to initialize the zone list. These steps are
specific to memory hotplug, and should be managed in mm/memory_hotplug.c.
lock_memory_hotplug() should also be held for the whole steps.
For this reason, this patch replaces mem_online_node() with
try_online_node(), which performs the whole steps with
lock_memory_hotplug() held. try_online_node() is named after
try_offline_node() as they have similar purpose.
Robin Holt [Tue, 5 Nov 2013 05:55:30 +0000 (16:55 +1100)]
mm/nobootmem.c: have __free_pages_memory() free in larger chunks.
On large memory machines it can take a few minutes to get through
free_all_bootmem().
Currently, when free_all_bootmem() calls __free_pages_memory(), the number
of contiguous pages that __free_pages_memory() passes to the buddy
allocator is limited to BITS_PER_LONG. BITS_PER_LONG was originally
chosen to keep things similar to mm/nobootmem.c. But it is more efficient
to limit it to MAX_ORDER.
base new change
8TB 202s 172s 30s
16TB 401s 351s 50s
That is around 1%-3% improvement on total boot time.
This patch was spun off from the boot time rfc Robin and I had been
working on.
Signed-off-by: Robin Holt <robin.m.holt@gmail.com> Signed-off-by: Nathan Zimmer <nzimmer@sgi.com> Cc: Robin Holt <robinmholt@linux.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Mike Travis <travis@sgi.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Mel Gorman <mgorman@suse.de> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Xishi Qiu [Tue, 5 Nov 2013 05:55:28 +0000 (16:55 +1100)]
mm/memory_hotplug.c: rename the function is_memblock_offlined_cb()
A is_memblock_offlined() return or 1 means memory block is offlined, but
is_memblock_offlined_cb() returning 1 means memory block is not offlined,
this will confuse somebody, so rename the function.
Jianguo Wu [Tue, 5 Nov 2013 05:55:26 +0000 (16:55 +1100)]
mm/huge_memory.c: fix stale comments of transparent_hugepage_flags
Since commit 13ece886d9 ("thp: transparent hugepage config choice"),
transparent hugepage support is disabled by default, and
TRANSPARENT_HUGEPAGE_ALWAYS is configured when TRANSPARENT_HUGEPAGE=y.
And since commit d39d33c332 ("thp: enable direct defrag"), defrag is
enable for all transparent hugepage page faults by default, not only in
MADV_HUGEPAGE regions.
Signed-off-by: Jianguo Wu <wujianguo@huawei.com> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Xishi Qiu [Tue, 5 Nov 2013 05:55:24 +0000 (16:55 +1100)]
mm/arch: use __free_reserved_page() to simplify the code
Use __free_reserved_page() to simplify the code in arch.
It used split_page() in consistent_alloc()/__dma_alloc_coherent()/dma_alloc_coherent(),
so page->_count == 1, and we can free it safely.
__free_reserved_page()
ClearPageReserved()
init_page_count() // it won't change the value
__free_page()
Signed-off-by: Xishi Qiu <qiuxishi@huawei.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jerome Marchand [Tue, 5 Nov 2013 05:55:24 +0000 (16:55 +1100)]
mm/compaction.c: update comment about zone lock in isolate_freepages_block
Since commit f40d1e4 ("mm: compaction: acquire the zone->lock as late as
possible"), isolate_freepages_block() takes the zone->lock itself. The
function description however still states that the zone->lock must be
held.
Joe Perches [Tue, 5 Nov 2013 05:55:23 +0000 (16:55 +1100)]
ksm: Remove redundant __GFP_ZERO from kcalloc
kcalloc returns zeroed memory. There's no need to use this flag.
Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Sasha Levin [Tue, 5 Nov 2013 05:55:22 +0000 (16:55 +1100)]
watchdog: trigger all-cpu backtrace when locked up and going to panic
Send an NMI to all CPUs when a lockup is detected and the lockup watchdog
code is configured to panic. This gives us a fairly uptodate snapshot of
all CPUs in the system.
This lets us get stack trace of all CPUs which makes life easier trying to
debug a deadlock, and the NMI doesn't change anything since the next step
is a kernel panic.
Oleg Nesterov [Tue, 5 Nov 2013 05:55:21 +0000 (16:55 +1100)]
anon_inodefs: forbid open via /proc
open("/proc/pid/$anon-fd") should fail, we can't create the new file with
correct f_op/etc correctly. Currently this creates the bogus file with
the empty anon_inode_fops, this is harmless but still wrong and
misleading.
Add anon_inode_fops->anon_open() which simply returns ENXIO like
sock_no_open() does in this case.
Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Josh Hunt [Tue, 5 Nov 2013 05:55:20 +0000 (16:55 +1100)]
block: restore /proc/partitions to not display non-partitionable removable devices
We found with newer kernels we started seeing the cdrom device showing
up in /proc/partitions, but it was not there before.
Looking into this I found that commit d27769ec ("block: add
GENHD_FL_NO_PART_SCAN") introduces this change in behavior. It's not
clear to me from the commit's changelog if this change was intentional or
not. This comment still remains: /* Don't show non-partitionable
removeable devices or empty devices */ so I've decided to send a patch to
restore the behavior of not printing unpartitionable removable devices.
Signed-off-by: Josh Hunt <johunt@akamai.com> Cc: Tejun Heo <tj@kernel.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
block: do not call sector_div() with a 64-bit divisor
do_div() (called by sector_div() if CONFIG_LBDAF=y) is meant for divisions
of 64-bit number by 32-bit numbers. Passing 64-bit divisor types caused
issues in the past on 32-bit platforms, cfr. commit ea077b1b96e073ea
("m68k: Truncate base in do_div()").
As queue_limits.max_discard_sectors and .discard_granularity are unsigned
int, max_discard_sectors and granularity should be unsigned int. As
bdev_discard_alignment() returns int, alignment should be int. Now 2
calls to sector_div() can be replaced by 32-bit arithmetic:
- The 64-bit modulo operation can become a 32-bit modulo operation,
- The 64-bit division and multiplication can be replaced by a 32-bit
modulo operation and a subtraction.
drivers/block/cciss.c: return 0 from driver probe function on success, not 1
A return value of 1 is interpreted as an error.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
hpsa: return 0 from driver probe function on success, not 1
A return value of 1 is interpreted as an error. See pci_driver. in
local_pci_probe(). If you're wondering how this ever could have worked,
it's because it used to be the case that only return values less than zero
were interpreted as failure. But even in the current kernel if the driver
registers its various entry points with the kernel, and then returns a
value which is interpreted as failure, those registrations aren't undone,
so the driver still mostly works. However, the driver's remove function
wouldn't be called on rmmod, and pci power management functions wouldn't
work. In the case of Smart Array, since it has a battery backed cache (or
else no cache) even if the driver is not shut down properly as long as
there is no outstanding i/o, nothing too bad happens, which is why it took
so long to notice.
Requesting backport to stable because the change to pci-driver.c which
requires driver probe functions to return 0 occurred between 2.6.35 and
2.6.36 (the pci power management breakage) and again between 3.7 and 3.8
(pci_dev->driver getting set to NULL in local_pci_probe() preventing
driver remove function from being called on rmmod.)
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure. Thus, it is not needed to manually clear the device driver
data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Gu Zheng [Tue, 5 Nov 2013 05:55:16 +0000 (16:55 +1100)]
fs/bio-integrity.c: remove duplicated code
Most code of function bio_integrity_verify and bio_integrity_generate is
the same, so introduce a common function bio_integrity_generate_verify()
to remove the reduplicate code.
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Jens Axboe <axboe@kernel.dk> Cc: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
do_div() is meant for divisions of 64-bit number by 32-bit numbers.
Passing 64-bit divisor types caused issues in the past on 32-bit
platforms, cfr. commit ea077b1b96e073eac5c ("m68k: Truncate base in
do_div()").
As scsi_device.sector_size is unsigned (int), factor should be unsigned
int, too.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Andrew Morton [Tue, 5 Nov 2013 05:55:14 +0000 (16:55 +1100)]
mm/readahead.c:do_readhead(): don't check for ->readpage
The callee force_page_cache_readahead() already does this and unlike
do_readahead(), force_page_cache_readahead() remembers to check for
->readpages() as well.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
drivers/pci/pci-driver.c: warn on driver probe return value greater than zero
Ages ago, drivers could return values greater than zero from their probe
function and this would be regarded as success. Commit f3ec4f87d607f40497
"PCI: change device runtime PM settings for probe and remove" slightly
altered this in 2010, and commit 967577b062417b4e4b8e27b ("PCI/PM: Keep
runtime PM enabled for unbound PCI devices") in late 2012 altered it more
signficantly, setting pci_dev->driver to NULL if the driver's probe
function returned a value greater than zero, which would for example
prevent the driver's remove function from being called on rmmod.
Neither of those changes would necessarily make the driver fail in an
obvious way though, and so at least a couple drivers (cciss, hpsa) fell
into this hole since they were returning 1, and this situation went
unnoticed for quite some time.
If a driver's probe function returns a value greater than zero, issue a
warning, but otherwise treat this as success.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Junxiao Bi [Tue, 5 Nov 2013 05:55:13 +0000 (16:55 +1100)]
ocfs2: update inode size after zeroing the hole
fs-writeback will release the dirty pages without page lock whose offset
are over inode size, the release happens at block_write_full_page_endio().
If not update, dirty pages in file holes may be released before flushed
to the disk, then file holes will contain some non-zero data, this will
cause sparse file md5sum error.
To reproduce the bug, find a big sparse file with many holes, like vm
image file, its actual size should be bigger than available mem size to
make writeback work more frequently, tar it with -S option, then keep
untar it and check its md5sum again and again until you get a wrong
md5sum.
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Younger Liu <younger.liu@huawei.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Younger Liu [Tue, 5 Nov 2013 05:55:13 +0000 (16:55 +1100)]
ocfs2: fix issue that ocfs2_setattr() does not deal with new_i_size==i_size
The issue scenario is as following:
- Create a small file and fallocate a large disk space for a file with
FALLOC_FL_KEEP_SIZE option.
- ftruncate the file back to the original size again. but the disk free
space is not changed back. This is a real bug that be fixed in this
patch.
In order to solve the issue above, we modified ocfs2_setattr(), if
attr->ia_size != i_size_read(inode), It calls ocfs2_truncate_file(), and
truncate disk space to attr->ia_size.
Signed-off-by: Younger Liu <younger.liu@huawei.com> Reviewed-by: Jie Liu <jeff.liu@oracle.com> Tested-by: Jie Liu <jeff.liu@oracle.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Reviewed-by: Jensen <shencanquan@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jensen [Tue, 5 Nov 2013 05:55:12 +0000 (16:55 +1100)]
ocfs2: llseek requires ocfs2 inode lock for the file in SEEK_END
llseek requires ocfs2 inode lock for updating the file size in SEEK_END.
because the file size maybe update on another node.
This bug can be reproduce the following scenario: at first, we dd a test
fileA, the file size is 10k.
on NodeA:
---------
1) open the test fileA, lseek the end of file. and print the position.
2) close the test fileA
on NodeB:
1) open the test fileA, append the 5k data to test FileA.
2) lseek the end of file. and print the position.
3) close file.
At first we run the test program1 on NodeA , the result is 10k. And then
run the test program2 on NodeB, the result is 15k. At last, we run the
test program1 on NodeA again, the result is 10k.
After applying this patch the three step result is 15k.
Signed-off-by: Jensen <shencanquan@huawei.com> Cc: Jie Liu <jeff.liu@oracle.com> Acked-by: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Younger Liu [Tue, 5 Nov 2013 05:55:11 +0000 (16:55 +1100)]
ocfs2: should call ocfs2_journal_access_di() before ocfs2_delete_entry() in ocfs2_orphan_del()
While deleting a file into orphan dir in ocfs2_orphan_del(), it calls
ocfs2_delete_entry() before ocfs2_journal_access_di(). If
ocfs2_delete_entry() succeeded and ocfs2_journal_access_di() failed, there
would be a inconsistency: the file is deleted from orphan dir, but orphan
dir dinode is not updated.
So we need to call ocfs2_journal_access_di() before ocfs2_orphan_del().
Signed-off-by: Younger Liu <younger.liu@huawei.com> Reviewed-by: Jensen <shencanquan@huawei.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
ocfs2: use the new DLM operation callbacks while requesting new lockspace
Attempt to use the new DLM operations. If it is not supported, use the
traditional ocfs2_controld.
To exchange ocfs2 versioning, we use the LVB of the version dlm lock. It
first attempts to take the lock in EX mode (non-blocking). If successful
(which means it is the first mount), it writes the version number and
downconverts to PR lock. If it is unsuccessful, it reads the version from
the lock.
If this becomes the standard (with o2cb as well), it could simplify
userspace tools to check if the filesystem is mounted on other nodes.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
ocfs2: pass ocfs2_cluster_connection to ocfs2_this_node
This is done to differentiate between using and not using controld and use
the connection information accordingly. We need to be backward
compatible. So, we use a new enum ocfs2_connection_type to identify when
controld is used and when it is not.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
ocfs2: shift allocation ocfs2_live_connection to user_connect()
We perform this because the DLM recovery callbacks will require the
ocfs2_live_connection structure to record the node information when
dlm_new_lockspace() is updated.
[AKPM] rc initialization is not required because it assigned in case of
errors. It will be cleared by compiler anyways.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
These are the callbacks called by the fs/dlm code in case the membership
changes. If there is a failure while/during calling any of these, the DLM
creates a new membership and relays to the rest of the nodes.
recover_prep() is called when DLM understands a node is down.
recover_slot() is called once all nodes have acknowledged recover_prep and
recovery can begin. recover_done() is called once the recovery is
complete. It returns the new membership.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This is an effort of removing ocfs2_controld.pcmk and getting ocfs2 DLM
handling up to the times with respect to DLM (>=4.0.1) and corosync
(2.3.x). AFAIK, cman also is being phased out for a unified corosync
cluster stack.
fs/dlm performs all the functions with respect to fencing and node
management and provides the API's to do so for ocfs2. For all future
references, DLM stands for fs/dlm code.
The advantages are:
+ No need to run an additional userspace daemon (ocfs2_controld)
+ No contrrold devince handling and controld protocol
+ Shifting responsibilities of node management to DLM layer
For backward compatibility, we are keeping the controld handling code.
Once enough time has passed we can remove a significant portion of the
code.
This feature requires modification in the userspace ocfs2-tools. The
changes can be found at: https://github.com/goldwynr/ocfs2-tools branch:
nocontrold Currently, not many checks are present in the userspace code,
but that would change soon.
These changes were developed on linux-stable 3.11.y. However, the changes
are applicable to the current upstream as well. If you wish to give the
entire kernel a spin, the link is:
Xue jiufei [Tue, 5 Nov 2013 05:55:08 +0000 (16:55 +1100)]
ocfs2: fix possible double free in ocfs2_write_begin_nolock
When ocfs2_write_cluster_by_desc() failed in ocfs2_write_begin_nolock()
because of ENOSPC, it goes to out_quota, freeing data_ac(meta_ac). Then
it calls ocfs2_try_to_free_truncate_log() to free space. If enough space
freed, it will try to write again. Unfortunately, some error happenes
before ocfs2_lock_allocators(), it goes to out and free data_ac(meta_ac)
again.
Signed-off-by: joyce <xuejiufei@huawei.com> Reviewed-by: Jie Liu <jeff.liu@oracle.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Younger Liu [Tue, 5 Nov 2013 05:55:07 +0000 (16:55 +1100)]
ocfs2: add missing errno in ocfs2_ioctl_move_extents()
If the file is not regular or writeable, it should return errno(EPERM).
This patch is based on 85a258b70d ("ocfs2: fix error handling in
ocfs2_ioctl_move_extents()").
Signed-off-by: Younger Liu <younger.liu@huawei.com> Signed-off-by: Jie Liu <jeff.liu@oracle.com> Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Jie Liu <jeff.liu@oracle.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Younger Liu [Tue, 5 Nov 2013 05:55:07 +0000 (16:55 +1100)]
ocfs2: do not call brelse() if group_bh is not initialized in ocfs2_group_add()
If group_bh is not initialized, there is no need to release. This problem
does not cause anything wrong, but the patch would make the code more
logical.
Signed-off-by: Younger Liu <younger.liu@huawei.com> Cc: Mark Fasheh <mfasheh@suse.com> Acked-by: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Younger Liu [Tue, 5 Nov 2013 05:55:06 +0000 (16:55 +1100)]
ocfs2: rollback transaction in ocfs2_group_add()
If ocfs2_journal_access_di() fails, group->bg_next_group should rollback.
Otherwise, there would be a inconsistency between group_bh and main_bm_bh.
Signed-off-by: Younger Liu <younger.liu@huawei.com> Cc: Mark Fasheh <mfasheh@suse.com> Acked-by: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Junxiao Bi [Tue, 5 Nov 2013 05:55:06 +0000 (16:55 +1100)]
ocfs2: break useless while loop
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Akinobu Mita [Tue, 5 Nov 2013 05:55:05 +0000 (16:55 +1100)]
ocfs2: use find_last_bit()
We already have find_last_bit(). So just use it as described in the
comment.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Xue jiufei [Tue, 5 Nov 2013 05:55:05 +0000 (16:55 +1100)]
ocfs2: delay migration when the lockres is in migration state
We trigger a bug in __dlm_lockres_reserve_ast() when we parallel umount 4
nodes. The situation is as follows:
1) Node A migrate all lockres it owned(eg. lockres A) to other nodes
say node B when it umounts.
2) Receiving MIG_LOCKRES message from A, Node B masters the lockres A
with DLM_LOCK_RES_MIGRATING state set.
3) Then we umount ocfs2 on node B. It also should migrate lockres A to
another node, say node C. But now, DLM_LOCK_RES_MIGRATING state of
lockers A is not cleared. Node B triggered the BUG on lockres with
state DLM_LOCK_RES_MIGRATING.
Signed-off-by: Xuejiufei <xuejiufei@huawei.com> Signed-off-by: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Tariq Saeed <tariq.x.saeed@oracle.com> Cc: Srinivas Eeda <srinivas.eeda@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Xue jiufei [Tue, 5 Nov 2013 05:55:04 +0000 (16:55 +1100)]
ocfs2: skip locks in the blocked list
A parallel umount on 4 nodes triggered a bug in
dlm_process_recovery_date(). Here's the situation:
Receiving MIG_LOCKRES message, A node processes the locks in migratable
lockres. It copys lvb from migratable lockres when processing the first
valid lock.
If there is a lock in the blocked list with the EX level, it triggers the
BUG. Since valid lvbs are set when locks are granted with EX or PR
levels, locks in the blocked list cannot have valid lvbs. Therefore I
think we should skip the locks in the blocked list.
Signed-off-by: Xuejiufei <xuejiufei@huawei.com> Signed-off-by: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Akinobu Mita [Tue, 5 Nov 2013 05:55:03 +0000 (16:55 +1100)]
ocfs2: use bitmap_weight()
Use bitmap_weight() instead of reinventing the wheel.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Joel Becker [Tue, 5 Nov 2013 05:55:03 +0000 (16:55 +1100)]
ocfs2: don't spam on -EDQUOT
-EDQUOT is a user-visible error, not a logic problem. Teach mlog_errno()
to ignore it like it ignores -ENOSPC, etc.
Signed-off-by: Joel Becker <jlbec@evilplan.org> Reviewed-by: Jan Kara <jack@suse.cz> Reported-by: Marek Królikowski <admin@wset.edu.pl> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Need also add a check after calling sb_getblk in ocfs2_create_xattr_block.
Cc: Rui Xiang <rui.xiang@huawei.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Rui Xiang [Tue, 5 Nov 2013 05:55:02 +0000 (16:55 +1100)]
ocfs2: add necessary check in case sb_getblk() fails
sb_getblk() may return an err, so add a check for bh.
Signed-off-by: Rui Xiang <rui.xiang@huawei.com> Reviewed-by: Jie Liu <jeff.liu@oracle.com> Reviewed-by: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Joseph Qi [Tue, 5 Nov 2013 05:55:01 +0000 (16:55 +1100)]
ocfs2-return-enomem-when-sb_getblk-fails-update
ocfs2_symlink_get_block in aops.c, and ocfs2_read_blocks_sync and
ocfs2_read_blocks in buffer_head_io.c need do the same change for
consistency.
Cc: Rui Xiang <rui.xiang@huawei.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Rui Xiang [Tue, 5 Nov 2013 05:55:01 +0000 (16:55 +1100)]
ocfs2: return ENOMEM when sb_getblk() fails
The only reason for sb_getblk() failing is if it can't allocate the
buffer_head. So return ENOMEM instead when it fails.
Signed-off-by: Rui Xiang <rui.xiang@huawei.com> Reviewed-by: Jie Liu <jeff.liu@oracle.com> Reviewed-by: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Junxiao Bi [Tue, 5 Nov 2013 05:55:00 +0000 (16:55 +1100)]
fs/ocfs2/file.c: fix wrong comment
Unwritten extent only exists for file systems which support holes. But
the comment said was opposite meaning and also the comment is not very
clear, so rephase it.
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jamie Iles [Tue, 5 Nov 2013 05:54:58 +0000 (16:54 +1100)]
scripts/sortextable: support objects with more than 64K sections.
Building with a large config and -ffunction-sections results in a large
number of sections and sortextable needs to be able to handle that.
Implement support for > 64K sections as modpost does.
Signed-off-by: Jamie Iles <jamie.iles@oracle.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Michal Marek <mmarek@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link input/leds.c along input/input.c instead of separate module
input.c needs to call leds.c and vice-versa, so it is simpler to stuff
them together. INPUT_LEDS thus now depends on LEDS_CLASS being available
enough for input.ko.
This also documents the new leds field.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
projects / karo-tx-linux.git / log