Pull cgroup updates from Tejun Heo:
- Fixes and a lot of cleanups. Locking cleanup is finally complete.
cgroup_mutex is no longer exposed to individual controlelrs which
used to cause nasty deadlock issues. Li fixed and cleaned up quite a
bit including long standing ones like racy cgroup_path().
- device cgroup now supports proper hierarchy thanks to Aristeu.
- perf_event cgroup now supports proper hierarchy.
- A new mount option "__DEVEL__sane_behavior" is added. As indicated
by the name, this option is to be used for development only at this
point and generates a warning message when used. Unfortunately,
cgroup interface currently has too many brekages and inconsistencies
to implement a consistent and unified hierarchy on top. The new flag
is used to collect the behavior changes which are necessary to
implement consistent unified hierarchy. It's likely that this flag
won't be used verbatim when it becomes ready but will be enabled
implicitly along with unified hierarchy.
The option currently disables some of broken behaviors in cgroup core
and also .use_hierarchy switch in memcg (will be routed through -mm),
which can be used to make very unusual hierarchy where nesting is
partially honored. It will also be used to implement hierarchy
support for blk-throttle which would be impossible otherwise without
introducing a full separate set of control knobs.
This is essentially versioning of interface which isn't very nice but
at this point I can't see any other options which would allow keeping
the interface the same while moving towards hierarchy behavior which
is at least somewhat sane. The planned unified hierarchy is likely
to require some level of adaptation from userland anyway, so I think
it'd be best to take the chance and update the interface such that
it's supportable in the long term.
Maintaining the existing interface does complicate cgroup core but
shouldn't put too much strain on individual controllers and I think
it'd be manageable for the foreseeable future. Maybe we'll be able
to drop it in a decade.
Fix up conflicts (including a semantic one adding a new #include to ppc
that was uncovered by header the file changes) as per Tejun.
* 'for-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (45 commits)
cpuset: fix compile warning when CONFIG_SMP=n
cpuset: fix cpu hotplug vs rebuild_sched_domains() race
cpuset: use rebuild_sched_domains() in cpuset_hotplug_workfn()
cgroup: restore the call to eventfd->poll()
cgroup: fix use-after-free when umounting cgroupfs
cgroup: fix broken file xattrs
devcg: remove parent_cgroup.
memcg: force use_hierarchy if sane_behavior
cgroup: remove cgrp->top_cgroup
cgroup: introduce sane_behavior mount option
move cgroupfs_root to include/linux/cgroup.h
cgroup: convert cgroupfs_root flag bits to masks and add CGRP_ prefix
cgroup: make cgroup_path() not print double slashes
Revert "cgroup: remove bind() method from cgroup_subsys."
perf: make perf_event cgroup hierarchical
cgroup: implement cgroup_is_descendant()
cgroup: make sure parent won't be destroyed before its children
cgroup: remove bind() method from cgroup_subsys.
devcg: remove broken_hierarchy tag
cgroup: remove cgroup_lock_is_held()
...
Pull workqueue updates from Tejun Heo:
"A lot of activities on workqueue side this time. The changes achieve
the followings.
- WQ_UNBOUND workqueues - the workqueues which are per-cpu - are
updated to be able to interface with multiple backend worker pools.
This involved a lot of churning but the end result seems actually
neater as unbound workqueues are now a lot closer to per-cpu ones.
- The ability to interface with multiple backend worker pools are
used to implement unbound workqueues with custom attributes.
Currently the supported attributes are the nice level and CPU
affinity. It may be expanded to include cgroup association in
future. The attributes can be specified either by calling
apply_workqueue_attrs() or through /sys/bus/workqueue/WQ_NAME/* if
the workqueue in question is exported through sysfs.
The backend worker pools are keyed by the actual attributes and
shared by any workqueues which share the same attributes. When
attributes of a workqueue are changed, the workqueue binds to the
worker pool with the specified attributes while leaving the work
items which are already executing in its previous worker pools
alone.
This allows converting custom worker pool implementations which
want worker attribute tuning to use workqueues. The writeback pool
is already converted in block tree and there are a couple others
are likely to follow including btrfs io workers.
- WQ_UNBOUND's ability to bind to multiple worker pools is also used
to make it NUMA-aware. Because there's no association between work
item issuer and the specific worker assigned to execute it, before
this change, using unbound workqueue led to unnecessary cross-node
bouncing and it couldn't be helped by autonuma as it requires tasks
to have implicit node affinity and workers are assigned randomly.
After these changes, an unbound workqueue now binds to multiple
NUMA-affine worker pools so that queued work items are executed in
the same node. This is turned on by default but can be disabled
system-wide or for individual workqueues.
Crypto was requesting NUMA affinity as encrypting data across
different nodes can contribute noticeable overhead and doing it
per-cpu was too limiting for certain cases and IO throughput could
be bottlenecked by one CPU being fully occupied while others have
idle cycles.
While the new features required a lot of changes including
restructuring locking, it didn't complicate the execution paths much.
The unbound workqueue handling is now closer to per-cpu ones and the
new features are implemented by simply associating a workqueue with
different sets of backend worker pools without changing queue,
execution or flush paths.
As such, even though the amount of change is very high, I feel
relatively safe in that it isn't likely to cause subtle issues with
basic correctness of work item execution and handling. If something
is wrong, it's likely to show up as being associated with worker pools
with the wrong attributes or OOPS while workqueue attributes are being
changed or during CPU hotplug.
While this creates more backend worker pools, it doesn't add too many
more workers unless, of course, there are many workqueues with unique
combinations of attributes. Assuming everything else is the same,
NUMA awareness costs an extra worker pool per NUMA node with online
CPUs.
There are also a couple things which are being routed outside the
workqueue tree.
- block tree pulled in workqueue for-3.10 so that writeback worker
pool can be converted to unbound workqueue with sysfs control
exposed. This simplifies the code, makes writeback workers
NUMA-aware and allows tuning nice level and CPU affinity via sysfs.
- The conversion to workqueue means that there's no 1:1 association
between a specific worker, which makes writeback folks unhappy as
they want to be able to tell which filesystem caused a problem from
backtrace on systems with many filesystems mounted. This is
resolved by allowing work items to set debug info string which is
printed when the task is dumped. As this change involves unifying
implementations of dump_stack() and friends in arch codes, it's
being routed through Andrew's -mm tree."
* 'for-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (84 commits)
workqueue: use kmem_cache_free() instead of kfree()
workqueue: avoid false negative WARN_ON() in destroy_workqueue()
workqueue: update sysfs interface to reflect NUMA awareness and a kernel param to disable NUMA affinity
workqueue: implement NUMA affinity for unbound workqueues
workqueue: introduce put_pwq_unlocked()
workqueue: introduce numa_pwq_tbl_install()
workqueue: use NUMA-aware allocation for pool_workqueues
workqueue: break init_and_link_pwq() into two functions and introduce alloc_unbound_pwq()
workqueue: map an unbound workqueues to multiple per-node pool_workqueues
workqueue: move hot fields of workqueue_struct to the end
workqueue: make workqueue->name[] fixed len
workqueue: add workqueue->unbound_attrs
workqueue: determine NUMA node of workers accourding to the allowed cpumask
workqueue: drop 'H' from kworker names of unbound worker pools
workqueue: add wq_numa_tbl_len and wq_numa_possible_cpumask[]
workqueue: move pwq_pool_locking outside of get/put_unbound_pool()
workqueue: fix memory leak in apply_workqueue_attrs()
workqueue: fix unbound workqueue attrs hashing / comparison
workqueue: fix race condition in unbound workqueue free path
workqueue: remove pwq_lock which is no longer used
...
Pull async update from Tejun Heo:
"This contains three cleanup patches for async from Lai. All three
patches are essentially cosmetic."
* 'for-3.10-async' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
async: rename and redefine async_func_ptr
async: remove unused @node from struct async_domain
async: simplify lowest_in_progress()
Pull percpu patch from Tejun Heo:
"A puny pull request for percpu. We were expecting more cleanup
patches but didn't happen this time, so just a single patch adding
documentation from Christoph."
* 'for-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu: add documentation on this_cpu operations
Merge first batch of fixes from Andrew Morton:
- A couple of kthread changes
- A few minor audit patches
- A number of fbdev patches. Florian remains AWOL so I'm picking up
some of these.
- A few kbuild things
- ocfs2 updates
- Almost all of the MM queue
(And in the meantime, I already have the second big batch from Andrew
pending in my mailbox ;^)
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (149 commits)
memcg: take reference before releasing rcu_read_lock
mem hotunplug: fix kfree() of bootmem memory
mmKconfig: add an option to disable bounce
mm, nobootmem: do memset() after memblock_reserve()
mm, nobootmem: clean-up of free_low_memory_core_early()
fs/buffer.c: remove unnecessary init operation after allocating buffer_head.
numa, cpu hotplug: change links of CPU and node when changing node number by onlining CPU
mm: fix memory_hotplug.c printk format warning
mm: swap: mark swap pages writeback before queueing for direct IO
swap: redirty page if page write fails on swap file
mm, memcg: give exiting processes access to memory reserves
thp: fix huge zero page logic for page with pfn == 0
memcg: avoid accessing memcg after releasing reference
fs: fix fsync() error reporting
memblock: fix missing comment of memblock_insert_region()
mm: Remove unused parameter of pages_correctly_reserved()
firmware, memmap: fix firmware_map_entry leak
mm/vmstat: add note on safety of drain_zonestat
mm: thp: add split tail pages to shrink page list in page reclaim
mm: allow for outstanding swap writeback accounting
...
Pull clock framework update from Michael Turquette:
"The common clock framework changes for 3.10 include many fixes for
existing platforms, as well as adoption of the framework by new
platforms and devices.
Some long-needed fixes to the core framework are here as well as new
features such as improved initialization of clocks from DT as well as
framework reentrancy for nested clock operations."
* tag 'clk-for-linus-3.10' of git://git.linaro.org/people/mturquette/linux: (44 commits)
clk: add clk_ignore_unused option to keep boot clocks on
clk: ux500: fix mismatched types
clk: vexpress: Add separate SP810 driver
clk: si5351: make clk-si5351 depend on CONFIG_OF
clk: export __clk_get_flags for modular clock providers
clk: vt8500: Missing breaks in vtwm_pll_round_rate/_set_rate.
clk: sunxi: Unify oscillator clock
clk: composite: allow fixed rates & fixed dividers
clk: composite: rename 'div' references to 'rate'
clk: add si5351 i2c common clock driver
clk: add device tree fixed-factor-clock binding support
clk: Properly handle notifier return values
clk: ux500: abx500: Define clock tree for ab850x
clk: ux500: Add support for sysctrl clocks
clk: mvebu: Fix valid value range checking for cpu_freq_select
clk: Fixup locking issues for clk_set_parent
clk: Fixup errorhandling for clk_set_parent
clk: Restructure code for __clk_reparent
clk: sunxi: drop an unnecesary kmalloc
clk: sunxi: drop CLK_IGNORE_UNUSED
...
Pull spi updates from Mark Brown:
"A fairly quiet release for SPI, mainly driver work. A few highlights:
- Supports bits per word compatibility checking in the core.
- Allow use of the IP used in Freescale SPI controllers outside
Freescale SoCs.
- DMA support for the Atmel SPI driver.
- New drivers for the BCM2835 and Tegra114"
* tag 'spi-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (68 commits)
spi-topcliff-pch: fix to use list_for_each_entry_safe() when delete list items
spi-topcliff-pch: missing platform_driver_unregister() on error in pch_spi_init()
ARM: dts: add pinctrl property for spi node for atmel SoC
ARM: dts: add spi nodes for the atmel boards
ARM: dts: add spi nodes for atmel SoC
ARM: at91: add clocks for spi dt entries
spi/spi-atmel: add dmaengine support
spi/spi-atmel: add flag to controller data for lock operations
spi/spi-atmel: add physical base address
spi/sirf: fix MODULE_DEVICE_TABLE
MAINTAINERS: Add git repository and update my address
spi/s3c64xx: Check for errors in dmaengine prepare_transfer()
spi/s3c64xx: Fix non-dmaengine usage
spi: omap2-mcspi: fix error return code in omap2_mcspi_probe()
spi/s3c64xx: let device core setup the default pin configuration
MAINTAINERS: Update Grant's email address and maintainership
spi: omap2-mcspi: Fix transfers if DMADEVICES is not set
spi: s3c64xx: move to generic dmaengine API
spi-gpio: init CS before spi_bitbang_setup()
spi: spi-mpc512x-psc: let transmiter/receiver enabled when in xfer loop
...
Pull regulator updates from Mark Brown:
"The diffstat and changelog here is dominated by Lee Jones' heroic
efforts to sync the ab8500 driver that's been maintained out of tree
with mainline (plus Axel's cleanup work on the results) but there's a
few other things here:
- Axel Lin added regulator_map_voltage_ascend() optimising a common
pattern for drivers using the core code.
- Milo Kim tought the regulator core to handle regulators sharing an
enable GPIO, avoiding the need to do hacks to support such systems.
- Andrew Bresticker added code to handle missing supplies for
regulators more sensibly for device tree systems, reducing the need
for stubbing there.
plus the usual batch of driver specific updates and fixes"
* tag 'regulator-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (152 commits)
regulator: mc13892: Fix MC13892_SWITCHERS0_SWxHI bit in set_voltage_sel
regulator: Remove NULL test before calling regulator_unregister()
regulator: mc13783: Add device tree probe support
regulator: mc13xxx: Add warning of incorrect names of regulators
regulator: max77686: Don't update max77686->opmode if update register fails
regulator: max8952: Add missing config.of_node setting for regulator register
regulator: ab3100: Fix regulator register error handling
regulator: tps6524x: Use regulator_map_voltage_ascend
regulator: lp8788-buck: Use regulator_map_voltage_ascend
regulator: lp872x: Use regulator_map_voltage_ascend
regulator: mc13892: Use regulator_map_voltage_ascend for mc13892_sw_regulator_ops
regulator: tps65023: Use regulator_map_voltage_ascend
regulator: tps65023: Merge tps65020 ldo1 and ldo2 vsel table
regulator: tps6507x: Use regulator_map_voltage_ascend
regulator: mc13892: Fix MC13892_SWITCHERS0_SWxHI bit in set_voltage_sel
regulator: ab3100: device tree support
regulator: ab3100: refactor probe to use IDs
regulator: max8973: Don't override control1 variable when set ramp delay bits
regulator: tps80031: Convert tps80031_dcdc_ops to [get|set]_voltage_sel_regmap
regulator: tps80031: Fix LDO2 track mode for TPS80031 or TPS80032-ES1.0
...
Pull regmap updates from Mark Brown:
"In user visible terms just a couple of enhancements here, though there
was a moderate amount of refactoring required in order to support the
register cache sync performance improvements.
- Support for block and asynchronous I/O during register cache
syncing; this provides a use case dependant performance
improvement.
- Additional debugfs information on the memory consuption and
register set"
* tag 'regmap-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: (23 commits)
regmap: don't corrupt work buffer in _regmap_raw_write()
regmap: cache: Fix format specifier in dev_dbg
regmap: cache: Make regcache_sync_block_raw static
regmap: cache: Write consecutive registers in a single block write
regmap: cache: Split raw and non-raw syncs
regmap: cache: Factor out block sync
regmap: cache: Factor out reg_present support from rbtree cache
regmap: cache: Use raw I/O to sync rbtrees if we can
regmap: core: Provide regmap_can_raw_write() operation
regmap: cache: Provide a get address of value operation
regmap: Cut down on the average # of nodes in the rbtree cache
regmap: core: Make raw write available to regcache
regmap: core: Warn on invalid operation combinations
regmap: irq: Clarify error message when we fail to request primary IRQ
regmap: rbtree Expose total memory consumption in the rbtree debugfs entry
regmap: debugfs: Add a registers `range' file
regmap: debugfs: Simplify calculation of `c->max_reg'
regmap: cache: Store caches in native register format where possible
regmap: core: Split out in place value parsing
regmap: cache: Use regcache_get_value() to check if we updated
...
The memcg is not referenced, so it can be destroyed at anytime right
after we exit rcu read section, so it's not safe to access it.
To fix this, we call css_tryget() to get a reference while we're still
in rcu read section.
This also removes a bogus comment above __memcg_create_cache_enqueue().
Signed-off-by: Li Zefan <lizefan@huawei.com>
Acked-by: Glauber Costa <glommer@parallels.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When hot removing memory presented at boot time, following messages are shown:
kernel BUG at mm/slub.c:3409!
invalid opcode: 0000 [#1] SMP
Modules linked in: ebtable_nat ebtables xt_CHECKSUM iptable_mangle bridge stp llc ipmi_devintf ipmi_msghandler sunrpc ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip_tables ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables binfmt_misc vfat fat dm_mirror dm_region_hash dm_log dm_mod vhost_net macvtap macvlan tun uinput iTCO_wdt iTCO_vendor_support coretemp kvm_intel kvm crc32c_intel ghash_clmulni_intel microcode pcspkr sg i2c_i801 lpc_ich mfd_core igb i2c_algo_bit i2c_core e1000e ptp pps_core tpm_infineon ioatdma dca sr_mod cdrom sd_mod crc_t10dif usb_storage megaraid_sas lpfc scsi_transport_fc scsi_tgt scsi_mod
CPU 0
Pid: 5091, comm: kworker/0:2 Tainted: G W 3.9.0-rc6+ #15
RIP: kfree+0x232/0x240
Process kworker/0:2 (pid: 5091, threadinfo ffff88084678c000, task ffff88083928ca80)
Call Trace:
__release_region+0xd4/0xe0
__remove_pages+0x52/0x110
arch_remove_memory+0x89/0xd0
remove_memory+0xc4/0x100
acpi_memory_device_remove+0x6d/0xb1
acpi_device_remove+0x89/0xab
__device_release_driver+0x7c/0xf0
device_release_driver+0x2f/0x50
acpi_bus_device_detach+0x6c/0x70
acpi_ns_walk_namespace+0x11a/0x250
acpi_walk_namespace+0xee/0x137
acpi_bus_trim+0x33/0x7a
acpi_bus_hot_remove_device+0xc4/0x1a1
acpi_os_execute_deferred+0x27/0x34
process_one_work+0x1f7/0x590
worker_thread+0x11a/0x370
kthread+0xee/0x100
ret_from_fork+0x7c/0xb0
RIP [<ffffffff811c41d2>] kfree+0x232/0x240
RSP <ffff88084678d968>
The reason why the messages are shown is to release a resource
structure, allocated by bootmem, by kfree(). So when we release a
resource structure, we should check whether it is allocated by bootmem
or not.
But even if we know a resource structure is allocated by bootmem, we
cannot release it since SLxB cannot treat it. So for reusing a resource
structure, this patch remembers it by using bootmem_resource as follows:
When releasing a resource structure by free_resource(), free_resource()
checks whether the resource structure is allocated by bootmem or not.
If it is allocated by bootmem, free_resource() adds it to
bootmem_resource. If it is not allocated by bootmem, free_resource()
release it by kfree().
And when getting a new resource structure by get_resource(),
get_resource() checks whether bootmem_resource has released resource
structures or not. If there is a released resource structure,
get_resource() returns it. If there is not a releaed resource
structure, get_resource() returns new resource structure allocated by
kzalloc().
[akpm@linux-foundation.org: s/get_resource/alloc_resource/]
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are times when HIGHMEM is enabled, but we don't prefer
CONFIG_BOUNCE to be enabled. CONFIG_BOUNCE can reduce the block device
throughput, and this is not ideal for machines where we don't gain much
by enabling it. So provide an option to deselect CONFIG_BOUNCE. The
observation was made while measuring eMMC throughput using iozone on an
ARM device with 1GB RAM.
Signed-off-by: Vinayak Menon <vinayakm.list@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PFN_PHYS() is a phys_addr_t, which can be u32 or u64.
Fix the build warning when phys_addr_t is u32.
mm/memory_hotplug.c: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 2 has type 'unsigned int' [-Wformat]: => 1685:3
mm/memory_hotplug.c: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'unsigned int' [-Wformat]: => 1685:3
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As pointed out by Andrew Morton, the swap-over-NFS writeback is not
setting PageWriteback before it is queued for direct IO. While swap
pages do not participate in BDI or process dirty accounting and the IO
is synchronous, the writeback bit is still required and not setting it
in this case was an oversight. swapoff depends on the page writeback to
synchronoise all pending writes on a swap page before it is reused.
Swapcache freeing and reuse depend on checking the PageWriteback under
lock to ensure the page is safe to reuse.
Direct IO handlers and the direct IO handler for NFS do not deal with
PageWriteback as they are synchronous writes. In the case of NFS, it
schedules pages (or a page in the case of swap) for IO and then waits
synchronously for IO to complete in nfs_direct_write(). It is
recognised that this is a slowdown from normal swap handling which is
asynchronous and uses a completion handler. Shoving PageWriteback
handling down into direct IO handlers looks like a bad fit to handle the
swap case although it may have to be dealt with some day if swap is
converted to use direct IO in general and bmap is finally done away
with. At that point it will be necessary to refit asynchronous direct
IO with completion handlers onto the swap subsystem.
As swapcache currently depends on PageWriteback to protect against
races, this patch sets PageWriteback under the page lock before queueing
it for direct IO. It is cleared when the direct IO handler returns. IO
errors are treated similarly to the direct-to-bio case except PageError
is not set as in the case of swap-over-NFS, it is likely to be a
transient error.
It was asked what prevents such a page being reclaimed in parallel.
With this patch applied, such a page will now be skipped (most of the
time) or blocked until the writeback completes. Reclaim checks
PageWriteback under the page lock before calling try_to_free_swap and
the page lock should prevent the page being requeued for IO before it is
freed.
This and Jerome's related patch should considered for -stable as far
back as 3.6 when swap-over-NFS was introduced.
[akpm@linux-foundation.org: use pr_err_ratelimited()]
[akpm@linux-foundation.org: remove hopefully-unneeded cast in printk]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org> [3.6+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit 62c230bc17 ("mm: add support for a filesystem to activate
swap files and use direct_IO for writing swap pages"), swap_writepage()
calls direct_IO on swap files. However, in that case the page isn't
redirtied if I/O fails, and is therefore handled afterwards as if it has
been successfully written to the swap file, leading to memory corruption
when the page is eventually swapped back in.
This patch sets the page dirty when direct_IO() fails. It fixes a
memory corruption that happened while using swap-over-NFS.
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org> [3.6+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A memcg may livelock when oom if the process that grabs the hierarchy's
oom lock is never the first process with PF_EXITING set in the memcg's
task iteration.
The oom killer, both global and memcg, will defer if it finds an
eligible process that is in the process of exiting and it is not being
ptraced. The idea is to allow it to exit without using memory reserves
before needlessly killing another process.
This normally works fine except in the memcg case with a large number of
threads attached to the oom memcg. In this case, the memcg oom killer
only gets called for the process that grabs the hierarchy's oom lock;
all others end up blocked on the memcg's oom waitqueue. Thus, if the
process that grabs the hierarchy's oom lock is never the first
PF_EXITING process in the memcg's task iteration, the oom killer is
constantly deferred without anything making progress.
The fix is to give PF_EXITING processes access to memory reserves so
that we've marked them as oom killed without any iteration. This allows
__mem_cgroup_try_charge() to succeed so that the process may exit. This
makes the memcg oom killer exemption for TIF_MEMDIE tasks, now
immediately granted for processes with pending SIGKILLs and those in the
exit path, to be equivalent to what is done for the global oom killer.
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Current implementation of huge zero page uses pfn value 0 to indicate
that the page hasn't allocated yet. It assumes that buddy page
allocator can't return page with pfn == 0.
Let's rework the code to store 'struct page *' of huge zero page, not
its pfn. This way we can avoid the weak assumption.
[akpm@linux-foundation.org: fix sparse warning]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Minchan Kim <minchan@kernel.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are two convenient ways to report errors to userspace
1) retun error to original syscall for example write(2)
2) mark mapping with error flag and return it on later fsync(2)
Second one is broken if (mapping->nrpages == 0) This is real-life
situation because after error pages are likey to be truncated or
invalidated.
We have to return an error regardless to number of pages in the mapping.
#Original testcase: git@github.com:dmonakhov/xfstests.git
MOUNT_OPTIONS="-b1024"
./check shared/305
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds
Li Zefan
Yasuaki Ishimatsu
Vinayak Menon
Joonsoo Kim
majianpeng
Randy Dunlap
Mel Gorman
Jerome Marchand
David Rientjes
Kirill A. Shutemov
Dmitry Monakhov
Tang Chen