10 Aug, 2010
40 commits
-
Cleanup, no functional changes.
- __set_personality() always changes ->exec_domain/personality, the
special case when ->exec_domain remains the same buys nothing but
complicates the code. Unify both cases to simplify the code.- The -EINVAL check in sys_personality() was never right. If we assume
that set_personality() can fail we should check the value it returns
instead of verifying that task->personality was actually changed.Remove it. Before the previous patch it was possible to hit this case
due to overflow problems, but this -EINVAL just indicated the kernel
bug.OTOH, probably it makes sense to change lookup_exec_domain() to return
ERR_PTR() instead of default_exec_domain if the search in exec_domains
list fails, and report this error to the user-space. But this means
another user-space change, and we have in-kernel users which need fixes.
For example, PER_OSF4 falls into PER_MASK for unkown reason and nobody
cares to register this domain.Signed-off-by: Oleg Nesterov
Cc: Wenming Zhang
Cc: "H. Peter Anvin"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This driver adds support for the BMP085 digital pressure sensor from Bosch
Sensortec. It exposes a sysfs api to userspace where pressure and
temperature measurement results can be read from the pressure0_input and
temp0_input file. The chip is able to calculate the average of up to
eight samples to increase the accuracy. This feature can be controlled by
writing to the oversampling file.The BMP085 digital pressure sensor can measure ambient air pressure and
temperature. Both values can be obtained from sysfs files. The pressure
is measured by reading from pressure0_input. Valid values range from
30000 to 110000 pascal with a resolution of 1 pascal (=0.01 millibar).temp0_input holds the current temperature in degree celsius, multiplied by
10. This results in a resolution of a tenth degree celsius. Values range
from -400 to 850.To increase the accuracy, this chip can calculate the average of 1, 2, 4
or 8 samples. This behavior is controlled through the oversampling sysfs
file. Two to the power of the value written to that file specifies how
many samples will be used. Valid values: 0..3.[akpm@linux-foundation.org: fix typo]
[shubhrajyoti@ti.com: optimize the wait time for the pressure sensor, definition of long is arch dependent so make it u32]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Christoph Mair
Signed-off-by: Shubhrajyoti D
Acked-by: Jonathan Cameron
Cc: Stefan Schmidt
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Fix i386 PAE compile warning:
drivers/misc/hpilo.c: In function `ilo_ccb_setup':
drivers/misc/hpilo.c:274: warning: cast to pointer from integer of different sizedma_addr_t is 64 on i386 PAE which causes a size mismatch.
Signed-off-by: Prarit Bhargava
Acked-by: David Altobelli
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add support for ROHM BH1780GLI Ambient light sensor.
BH1780 supports I2C interface. Driver supports read/update of power state
and read of lux value (through SYSFS). Writing value 3 to power_state
enables the sensor and current lux value could be read.Currently this driver follows the same sysfs convention as supported by
drivers/misc/isl29003.c.Signed-off-by: Hemanth V
Reviewed-by: Daniel Mack
Acked-by: Jonathan Cameron
Cc: Jean Delvare
Cc: Wolfram Sang
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
sec2annotation returns malloc'ed buffer directly to printf as an argument.
Free this buffer after printing.Signed-off-by: Alexey Fomenko
Cc: Trevor Keith
Cc: Rusty Russell
Cc: Michal Marek
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
A profile of a network benchmark showed iommu_num_pages rather high up:
0.52% iommu_num_pages
Looking at the profile, an integer divide is taking almost all of the time:
%
: c000000000376ea4 :
1.93 : c000000000376ea4: fb e1 ff f8 std r31,-8(r1)
0.00 : c000000000376ea8: f8 21 ff c1 stdu r1,-64(r1)
0.00 : c000000000376eac: 7c 3f 0b 78 mr r31,r1
3.86 : c000000000376eb0: 38 84 ff ff addi r4,r4,-1
0.00 : c000000000376eb4: 38 05 ff ff addi r0,r5,-1
0.00 : c000000000376eb8: 7c 84 2a 14 add r4,r4,r5
46.95 : c000000000376ebc: 7c 00 18 38 and r0,r0,r3
45.66 : c000000000376ec0: 7c 84 02 14 add r4,r4,r0
0.00 : c000000000376ec4: 7c 64 2b 92 divdu r3,r4,r5
0.00 : c000000000376ec8: 38 3f 00 40 addi r1,r31,64
0.00 : c000000000376ecc: eb e1 ff f8 ld r31,-8(r1)
1.61 : c000000000376ed0: 4e 80 00 20 blrSince every caller of iommu_num_pages passes in a constant power of two
we can inline this such that the divide is replaced by a shift. The
entire function is only a few instructions once optimised, so it is
a good candidate for inlining overall.Signed-off-by: Anton Blanchard
Cc: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Using:
gcc (GCC) 4.5.0 20100610 (prerelease)
The following warnings appear:
fs/readdir.c: In function `filldir64':
fs/readdir.c:240:15: warning: `dirent' is used uninitialized in this function
fs/readdir.c: In function `filldir':
fs/readdir.c:155:15: warning: `dirent' is used uninitialized in this function
fs/compat.c: In function `compat_filldir64':
fs/compat.c:1071:11: warning: `dirent' is used uninitialized in this function
fs/compat.c: In function `compat_filldir':
fs/compat.c:984:15: warning: `dirent' is used uninitialized in this functionThe warnings are related to the use of the NAME_OFFSET() macro. Luckily,
it appears as though the standard offsetof() macro is what is being
implemented by NAME_OFFSET(), thus we can fix the warning and use a more
standard code construct at the same time.Signed-off-by: Kevin Winchester
Cc: Al Viro
Cc: Christoph Hellwig
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add more information about patch descriptions.
Signed-off-by: Randy Dunlap
Reviewed-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
There are no more uses of NIPQUAD or NIPQUAD_FMT. Remove the definitions.
Signed-off-by: Joe Perches
Cc: "David S. Miller"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Removal of these started in 2.3.43pre3, ca. 10 years ago.
Reported-by: Arnd Bergmann
Signed-off-by: Geert Uytterhoeven
Cc: Richard Henderson
Cc: Ivan Kokshaysky
Cc: Yoshinori Sato
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
We should use the __same_type() helper in __must_be_array().
Signed-off-by: Rusty Russell
Reported-by: Andrew Morton
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The asm-generic/iomap.h provides these functions already, but the
non-generic fallback defines do not.Signed-off-by: Mike Frysinger
Cc: Arnd Bergmann
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
PROC_MM doesn't exist in Kconfig. Looking around it looks like a
left-over from 2.6.0 or even 2.4 times, last mentioned in a fedora patch
for 2.6.10. I believe it's time to get rid of that last tiny parts here
that are still around.Signed-off-by: Christoph Egger
Cc: Jeff Dike
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When I use OpenSUSE-11.2 on UML (> 2.6.25)
I get lots of such errors:Registering fd 1 twice
Irqs : 3, 3
Ids : 0x09cb41a0, 0x09cb4120
------------[ cut here ]------------
WARNING: at kernel/irq/manage.c:896 __free_irq+0x79/0x11a()
Trying to free already-free IRQ 3
Modules linked in:
09dadc6c: [] dump_stack+0x1c/0x20
09dadc84: [] warn_slowpath_common+0x49/0x77
09dadc9c: [] warn_slowpath_fmt+0x26/0x2a
09dadcb4: [] __free_irq+0x79/0x11a
09dadce4: [] free_irq+0x2d/0x49
09dadcf4: [] close_one_chan+0x70/0x9c
09dadd0c: [] close_chan+0x17/0x22
09dadd1c: [] enable_chan+0x70/0x7c
09dadd3c: [] line_open+0x34/0x9f
09dadd54: [] con_open+0x13/0x35
09dadd6c: [] tty_open+0x285/0x384
09dadda0: [] chrdev_open+0xe0/0xf9
09daddc0: [] __dentry_open+0xf3/0x1e2
09dadde4: [] nameidata_to_filp+0x35/0x49
09daddfc: [] do_last+0x409/0x50e
09dade28: [] do_filp_open+0x175/0x446
09dadecc: [] do_sys_open+0x4a/0x128
09dadf04: [] sys_open+0x19/0x21
09dadf28: [] handle_syscall+0x7a/0x98
09dadf78: [] userspace+0x2c9/0x370
09dadfe0: [] fork_handler+0x53/0x5b
09dadffc: [] 0x766564---[ end trace 9ebc1094aaf4bded ]---
This patch fixes the issue.
Signed-off-by: Richard Weinberger
Cc: Jeff Dike
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
On some SoC chips, HW resources may be in use during any particular idle
period. As a consequence, the cpuidle states that the SoC is safe to
enter can change from idle period to idle period. In addition, the
latency and threshold of each cpuidle state can vary, depending on the
operating condition when the CPU becomes idle, e.g. the current cpu
frequency, the current state of the HW blocks, etc.cpuidle core and the menu governor, in the current form, are geared
towards cpuidle states that are static, i.e. the availabiltiy of the
states, their latencies, their thresholds are non-changing during run
time. cpuidle does not provide any hook that cpuidle drivers can use to
adjust those values on the fly for the current idle period before the menu
governor selects the target cpuidle state.This patch extends cpuidle core and the menu governor to handle states
that are dynamic. There are three additions in the patch and the patch
maintains backwards-compatibility with existing cpuidle drivers.1) add prepare() to struct cpuidle_device. A cpuidle driver can hook
into the callback and cpuidle will call prepare() before calling the
governor's select function. The callback gives the cpuidle driver a
chance to update the dynamic information of the cpuidle states for the
current idle period, e.g. state availability, latencies, thresholds,
power values, etc.2) add CPUIDLE_FLAG_IGNORE as one of the state flags. In the prepare()
function, a cpuidle driver can set/clear the flag to indicate to the
menu governor whether a cpuidle state should be ignored, i.e. not
available, during the current idle period.3) add power_specified bit to struct cpuidle_device. The menu governor
currently assumes that the cpuidle states are arranged in the order of
increasing latency, threshold, and power savings. This is true or can
be made true for static states. Once the state parameters are dynamic,
the latencies, thresholds, and power savings for the cpuidle states can
increase or decrease by different amounts from idle period to idle
period. So the assumption of increasing latency, threshold, and power
savings from Cn to C(n+1) can no longer be guaranteed.It can be straightforward to calculate the power consumption of each
available state and to specify it in power_usage for the idle period.
Using the power_usage fields, the menu governor then selects the state
that has the lowest power consumption and that still satisfies all other
critieria. The power_specified bit defaults to 0. For existing cpuidle
drivers, cpuidle detects that power_specified is 0 and fills in a dummy
set of power_usage values.Signed-off-by: Ai Li
Cc: Len Brown
Acked-by: Arjan van de Ven
Cc: Ingo Molnar
Cc: Venkatesh Pallipadi
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When taking a memory snapshot in hibernate_snapshot(), all (directly
called) memory allocations use GFP_ATOMIC. Hence swap misusage during
hibernation never occurs.But from a pessimistic point of view, there is no guarantee that no page
allcation has __GFP_WAIT. It is better to have a global indication "we
enter hibernation, don't use swap!".This patch tries to freeze new-swap-allocation during hibernation. (All
user processes are frozenm so swapin is not a concern).This way, no updates will happen to swap_map[] between
hibernate_snapshot() and save_image(). Swap is thawed when swsusp_free()
is called. We can be assured that swap corruption will not occur.Signed-off-by: KAMEZAWA Hiroyuki
Cc: "Rafael J. Wysocki"
Cc: Hugh Dickins
Cc: KOSAKI Motohiro
Cc: Ondrej Zary
Cc: Balbir Singh
Cc: Andrea Arcangeli
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Since 2.6.31, swap_map[]'s refcounting was changed to show that a used
swap entry is just for swap-cache, can be reused. Then, while scanning
free entry in swap_map[], a swap entry may be able to be reclaimed and
reused. It was caused by commit c9e444103b5e7a5 ("mm: reuse unused swap
entry if necessary").But this caused deta corruption at resume. The scenario is
- Assume a clean-swap cache, but mapped.
- at hibernation_snapshot[], clean-swap-cache is saved as
clean-swap-cache and swap_map[] is marked as SWAP_HAS_CACHE.- then, save_image() is called. And reuse SWAP_HAS_CACHE entry to save
image, and break the contents.After resume:
- the memory reclaim runs and finds clean-not-referenced-swap-cache and
discards it because it's marked as clean. But here, the contents on
disk and swap-cache is inconsistent.Hance memory is corrupted.
This patch avoids the bug by not reclaiming swap-entry during hibernation.
This is a quick fix for backporting.Signed-off-by: KAMEZAWA Hiroyuki
Cc: Rafael J. Wysocki
Reported-by: Ondreg Zary
Tested-by: Ondreg Zary
Tested-by: Andrea Gelmini
Acked-by: Hugh Dickins
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This implements hardware performance events for the EV67 and later CPUs
within the Linux performance events subsystem. Only using the performance
monitoring unit in HP/Compaq's so called "Aggregrate mode" is supported.The code has been implemented in a manner that makes extension to other
older Alpha CPUs relatively straightforward should some mug wish to
indulge themselves.Signed-off-by: Michael Cree
Cc: Richard Henderson
Cc: Ivan Kokshaysky
Cc: Matt Turner
Cc: Thomas Gleixner
Cc: Peter Zijlstra
Cc: Ingo Molnar
Cc: Jay Estabrook
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Signed-off-by: Michael Cree
Cc: Richard Henderson
Cc: Ivan Kokshaysky
Cc: Matt Turner
Cc: Thomas Gleixner
Cc: Peter Zijlstra
Cc: Ingo Molnar
Cc: Jay Estabrook
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The following patches implement hardware performance events for the Alpha
EV67 and later CPUs. I have had this running on a Compaq XP1000 (EV67,
single CPU) for a few days now. Pretty cool -- discovered that the glibc
exp2() library routine uses on average 985 cycles to execute 777 CPU
instructions whereas Compaq's CPML library version of exp2() uses on
average 32 cycles to execute 47 CPU instructions to achieve the same
thing!This patch:
Add performance monitor interrupt counternd and export the count to user
space via /proc/interrupts.Signed-off-by: Michael Cree
Cc: Richard Henderson
Cc: Ivan Kokshaysky
Cc: Matt Turner
Cc: Thomas Gleixner
Cc: Peter Zijlstra
Cc: Ingo Molnar
Cc: Jay Estabrook
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
WB_SYNC_NONE writeback is done in rounds of 1024 pages so that we don't
write out some huge inode for too long while starving writeout of other
inodes. To avoid livelocks, we record time we started writeback in
wbc->wb_start and do not write out inodes which were dirtied after this
time. But currently, writeback_inodes_wb() resets wb_start each time it
is called thus effectively invalidating this logic and making any
WB_SYNC_NONE writeback prone to livelocks.This patch makes sure wb_start is set only once when we start writeback.
Signed-off-by: Jan Kara
Reviewed-by: Wu Fengguang
Cc: Christoph Hellwig
Acked-by: Jens Axboe
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Use compile-allocated memory instead of dynamic allocated memory for
mm_slots_hash.Use hash_ptr() instead divisions for bucket calculation.
Signed-off-by: Lai Jiangshan
Signed-off-by: Izik Eidus
Cc: Avi Kivity
Cc: Andrea Arcangeli
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Fix "system goes unresponsive under memory pressure and lots of
dirty/writeback pages" bug.http://lkml.org/lkml/2010/4/4/86
In the above thread, Andreas Mohr described that
Invoking any command locked up for minutes (note that I'm
talking about attempted additional I/O to the _other_,
_unaffected_ main system HDD - such as loading some shell
binaries -, NOT the external SSD18M!!).This happens when the two conditions are both meet:
- under memory pressure
- writing heavily to a slow deviceOOM also happens in Andreas' system. The OOM trace shows that 3 processes
are stuck in wait_on_page_writeback() in the direct reclaim path. One in
do_fork() and the other two in unix_stream_sendmsg(). They are blocked on
this condition:(sc->order && priority < DEF_PRIORITY - 2)
which was introduced in commit 78dc583d (vmscan: low order lumpy reclaim
also should use PAGEOUT_IO_SYNC) one year ago. That condition may be too
permissive. In Andreas' case, 512MB/1024 = 512KB. If the direct reclaim
for the order-1 fork() allocation runs into a range of 512KB
hard-to-reclaim LRU pages, it will be stalled.It's a severe problem in three ways.
Firstly, it can easily happen in daily desktop usage. vmscan priority can
easily go below (DEF_PRIORITY - 2) on _local_ memory pressure. Even if
the system has 50% globally reclaimable pages, it still has good
opportunity to have 0.1% sized hard-to-reclaim ranges. For example, a
simple dd can easily create a big range (up to 20%) of dirty pages in the
LRU lists. And order-1 to order-3 allocations are more than common with
SLUB. Try "grep -v '1 :' /proc/slabinfo" to get the list of high order
slab caches. For example, the order-1 radix_tree_node slab cache may
stall applications at swap-in time; the order-3 inode cache on most
filesystems may stall applications when trying to read some file; the
order-2 proc_inode_cache may stall applications when trying to open a
/proc file.Secondly, once triggered, it will stall unrelated processes (not doing IO
at all) in the system. This "one slow USB device stalls the whole system"
avalanching effect is very bad.Thirdly, once stalled, the stall time could be intolerable long for the
users. When there are 20MB queued writeback pages and USB 1.1 is writing
them in 1MB/s, wait_on_page_writeback() will stuck for up to 20 seconds.
Not to mention it may be called multiple times.So raise the bar to only enable PAGEOUT_IO_SYNC when priority goes below
DEF_PRIORITY/3, or 6.25% LRU size. As the default dirty throttle ratio is
20%, it will hardly be triggered by pure dirty pages. We'd better treat
PAGEOUT_IO_SYNC as some last resort workaround -- its stall time is so
uncomfortably long (easily goes beyond 1s).The bar is only raised for (order < PAGE_ALLOC_COSTLY_ORDER) allocations,
which are easy to satisfy in 1TB memory boxes. So, although 6.25% of
memory could be an awful lot of pages to scan on a system with 1TB of
memory, it won't really have to busy scan that much.Andreas tested an older version of this patch and reported that it mostly
fixed his problem. Mel Gorman helped improve it and KOSAKI Motohiro will
fix it further in the next patch.Reported-by: Andreas Mohr
Reviewed-by: Minchan Kim
Reviewed-by: KOSAKI Motohiro
Signed-off-by: Mel Gorman
Signed-off-by: Wu Fengguang
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
kmalloc() may fail, if so return -ENOMEM.
Signed-off-by: Kulikov Vasiliy
Acked-by: Pekka Enberg
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Memcg also need to trace page isolation information as global reclaim.
This patch does it.Signed-off-by: KOSAKI Motohiro
Reviewed-by: KAMEZAWA Hiroyuki
Acked-by: Mel Gorman
Acked-by: Balbir Singh
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Mel Gorman recently added some vmscan tracepoints. Unfortunately they are
covered only global reclaim. But we want to trace memcg reclaim too.Thus, this patch convert them to DEFINE_TRACE macro. it help to reuse
tracepoint definition for other similar usage (i.e. memcg). This patch
have no functionally change.Signed-off-by: KOSAKI Motohiro
Reviewed-by: KAMEZAWA Hiroyuki
Acked-by: Balbir Singh
Acked-by: Mel Gorman
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Memcg also need to trace reclaim progress as direct reclaim. This patch
add it.Signed-off-by: KOSAKI Motohiro
Reviewed-by: KAMEZAWA Hiroyuki
Acked-by: Mel Gorman
Acked-by: Balbir Singh
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Mel Gorman recently added some vmscan tracepoints. Unfortunately they are
covered only global reclaim. But we want to trace memcg reclaim too.Thus, this patch convert them to DEFINE_TRACE macro. it help to reuse
tracepoint definition for other similar usage (i.e. memcg). This patch
have no functionally change.Signed-off-by: KOSAKI Motohiro
Reviewed-by: KAMEZAWA Hiroyuki
Acked-by: Mel Gorman
Acked-by: Balbir Singh
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Presently shrink_slab() has the following scanning equation.
lru_scanned max_pass
basic_scan_objects = 4 x ------------- x -----------------------------
lru_pages shrinker->seeks (default:2)scan_objects = min(basic_scan_objects, max_pass * 2)
If we pass very small value as lru_pages instead real number of lru pages,
shrink_slab() drop much objects rather than necessary. And now,
__zone_reclaim() pass 'order' as lru_pages by mistake. That produces a
bad result.For example, if we receive very low memory pressure (scan = 32, order =
0), shrink_slab() via zone_reclaim() always drop _all_ icache/dcache
objects. (see above equation, very small lru_pages make very big
scan_objects result).This patch fixes it.
[akpm@linux-foundation.org: fix layout, typos]
Signed-off-by: KOSAKI Motohiro
Reviewed-by: Minchan Kim
Acked-by: Christoph Lameter
Acked-by: Rik van Riel
Cc: Johannes Weiner
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
It is not appropriate for apply_to_page_range() to directly call any mmu
notifiers, because it is a general purpose function whose effect depends
on what context it is called in and what the callback function does.In particular, if it is being used as part of an mmu notifier
implementation, the recursive calls can be particularly problematic.It is up to apply_to_page_range's caller to do any notifier calls if
necessary. It does not affect any in-tree users because they all operate
on init_mm, and mmu notifiers only pertain to usermode mappings.[stefano.stabellini@eu.citrix.com: remove unused local `start']
Signed-off-by: Jeremy Fitzhardinge
Signed-off-by: Stefano Stabellini
Cc: Andrea Arcangeli
Cc: Stefano Stabellini
Cc: Avi Kivity
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Rik van Riel pointed out reading reclaim_stat should be protected
lru_lock, otherwise vmscan might sweep 2x much pages.This fault was introduced by
commit 4f98a2fee8acdb4ac84545df98cccecfd130f8db
Author: Rik van Riel
Date: Sat Oct 18 20:26:32 2008 -0700vmscan: split LRU lists into anon & file sets
Signed-off-by: KOSAKI Motohiro
Cc: Rik van Riel
Reviewed-by: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
'slab_reclaimable' and 'nr_pages' are unsigned. Subtraction is unsafe
because negative results would be misinterpreted.Signed-off-by: KOSAKI Motohiro
Reviewed-by: Minchan Kim
Cc: Mel Gorman
Cc: Rik van Riel
Cc: Johannes Weiner
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
drivers/base/node.c: In function 'node_read_meminfo':
drivers/base/node.c:139: warning: the frame size of 848 bytes is
larger than 512 bytesFix it by splitting the sprintf() into three parts. It has no functional
change.Signed-off-by: KOSAKI Motohiro
Cc: Greg KH
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Set the flag if do_swap_page is decowing the page the same way do_wp_page
would too.Signed-off-by: Andrea Arcangeli
Cc: KOSAKI Motohiro
Cc: Rik van Riel
Cc: Nick Piggin
Cc: Hugh Dickins
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
On swapin it is fairly common for a page to be owned exclusively by one
process. In that case we want to add the page to the anon_vma of that
process's VMA, instead of to the root anon_vma.This will reduce the amount of rmap searching that the swapout code needs
to do.Signed-off-by: Rik van Riel
Cc: Andrea Arcangeli
Cc: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
/proc/pid/oom_adj is now deprecated so that that it may eventually be
removed. The target date for removal is August 2012.A warning will be printed to the kernel log if a task attempts to use this
interface. Future warning will be suppressed until the kernel is rebooted
to prevent spamming the kernel log.Signed-off-by: David Rientjes
Cc: Nick Piggin
Cc: KAMEZAWA Hiroyuki
Cc: KOSAKI Motohiro
Cc: Oleg Nesterov
Cc: Balbir Singh
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This a complete rewrite of the oom killer's badness() heuristic which is
used to determine which task to kill in oom conditions. The goal is to
make it as simple and predictable as possible so the results are better
understood and we end up killing the task which will lead to the most
memory freeing while still respecting the fine-tuning from userspace.Instead of basing the heuristic on mm->total_vm for each task, the task's
rss and swap space is used instead. This is a better indication of the
amount of memory that will be freeable if the oom killed task is chosen
and subsequently exits. This helps specifically in cases where KDE or
GNOME is chosen for oom kill on desktop systems instead of a memory
hogging task.The baseline for the heuristic is a proportion of memory that each task is
currently using in memory plus swap compared to the amount of "allowable"
memory. "Allowable," in this sense, means the system-wide resources for
unconstrained oom conditions, the set of mempolicy nodes, the mems
attached to current's cpuset, or a memory controller's limit. The
proportion is given on a scale of 0 (never kill) to 1000 (always kill),
roughly meaning that if a task has a badness() score of 500 that the task
consumes approximately 50% of allowable memory resident in RAM or in swap
space.The proportion is always relative to the amount of "allowable" memory and
not the total amount of RAM systemwide so that mempolicies and cpusets may
operate in isolation; they shall not need to know the true size of the
machine on which they are running if they are bound to a specific set of
nodes or mems, respectively.Root tasks are given 3% extra memory just like __vm_enough_memory()
provides in LSMs. In the event of two tasks consuming similar amounts of
memory, it is generally better to save root's task.Because of the change in the badness() heuristic's baseline, it is also
necessary to introduce a new user interface to tune it. It's not possible
to redefine the meaning of /proc/pid/oom_adj with a new scale since the
ABI cannot be changed for backward compatability. Instead, a new tunable,
/proc/pid/oom_score_adj, is added that ranges from -1000 to +1000. It may
be used to polarize the heuristic such that certain tasks are never
considered for oom kill while others may always be considered. The value
is added directly into the badness() score so a value of -500, for
example, means to discount 50% of its memory consumption in comparison to
other tasks either on the system, bound to the mempolicy, in the cpuset,
or sharing the same memory controller./proc/pid/oom_adj is changed so that its meaning is rescaled into the
units used by /proc/pid/oom_score_adj, and vice versa. Changing one of
these per-task tunables will rescale the value of the other to an
equivalent meaning. Although /proc/pid/oom_adj was originally defined as
a bitshift on the badness score, it now shares the same linear growth as
/proc/pid/oom_score_adj but with different granularity. This is required
so the ABI is not broken with userspace applications and allows oom_adj to
be deprecated for future removal.Signed-off-by: David Rientjes
Cc: Nick Piggin
Cc: KAMEZAWA Hiroyuki
Cc: KOSAKI Motohiro
Cc: Oleg Nesterov
Cc: Balbir Singh
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Cc: Minchan Kim
Cc: David Rientjes
Cc: KAMEZAWA Hiroyuki
Cc: Oleg Nesterov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Oleg pointed out current PF_EXITING check is wrong. Because PF_EXITING
is per-thread flag, not per-process flag. He said,Two threads, group-leader L and its sub-thread T. T dumps the code.
In this case both threads have ->mm != NULL, L has PF_EXITING.The first problem is, select_bad_process() always return -1 in this
case (even if the caller is T, this doesn't matter).The second problem is that we should add TIF_MEMDIE to T, not L.
I think we can remove this dubious PF_EXITING check. but as first step,
This patch add the protection of multi threaded issue.Signed-off-by: KOSAKI Motohiro
Cc: Oleg Nesterov
Cc: Minchan Kim
Cc: David Rientjes
Cc: KAMEZAWA Hiroyuki
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In a system under heavy load it was observed that even after the
oom-killer selects a task to die, the task may take a long time to die.Right after sending a SIGKILL to the task selected by the oom-killer this
task has its priority increased so that it can exit() soon, freeing
memory. That is accomplished by:/*
* We give our sacrificial lamb high priority and access to
* all the memory it needs. That way it should be able to
* exit() and clear out its resources quickly...
*/
p->rt.time_slice = HZ;
set_tsk_thread_flag(p, TIF_MEMDIE);It sounds plausible giving the dying task an even higher priority to be
sure it will be scheduled sooner and free the desired memory. It was
suggested on LKML using SCHED_FIFO:1, the lowest RT priority so that this
task won't interfere with any running RT task.If the dying task is already an RT task, leave it untouched. Another good
suggestion, implemented here, was to avoid boosting the dying task
priority in case of mem_cgroup OOM.Signed-off-by: Luis Claudio R. Goncalves
Signed-off-by: KOSAKI Motohiro
Reviewed-by: Minchan Kim
Cc: David Rientjes
Cc: KAMEZAWA Hiroyuki
Cc: Oleg Nesterov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
