11 Aug, 2010
19 commits
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Fix kernel-doc warnings in linux/usb.h:
Warning(include/linux/usb.h:185): No description found for parameter 'resetting_device'
Warning(include/linux/usb.h:1212): No description found for parameter 'stream_id'Signed-off-by: Randy Dunlap
Signed-off-by: Greg Kroah-Hartman -
The Logitech Harmony 700 series needs an extra delay during
initialization. This patch adds a USB quirk which enables such a delay
and adds the device to the quirks list.Signed-off-by: Phil Dibowitz
Cc: stable
Signed-off-by: Greg Kroah-Hartman -
1) Introduce ulpi specific flags for control of the ulpi phy
2) Extend the generic ulpi driver with support for Function and
Interface control of upli phy
3) Update the platforms using the generic ulpi driver with new ulpi
flags
4) Remove the otg control flags not in useSigned-off-by: Igor Grinberg
Signed-off-by: Mike Rapoport
Signed-off-by: Greg Kroah-Hartman -
Fixes below compilation warning from ulpi.h
include/linux/usb/ulpi.h:145:
warning: 'struct otg_io_access_ops' declared inside parameter list
include/linux/usb/ulpi.h:145:
warning: its scope is only this definition or declaration,
which is probably not what you wantSigned-off-by: Ajay Kumar Gupta
Signed-off-by: Greg Kroah-Hartman -
This patch (as1395) adds code to hcd_pci_suspend() for handling wakeup
races. This is another general race pattern, similar to the "open
vs. unregister" race we're all familiar with. Here, the race is
between suspending a device and receiving a wakeup request from one of
the device's suspended children.In particular, if a root-hub wakeup is requested at about the same
time as the corresponding USB controller is suspended, and if the
controller is enabled for wakeup, then the controller should either
fail to suspend or else wake right back up again.During system sleep this won't happen very much, especially since host
controllers generally aren't enabled for wakeup during sleep. However
it is definitely an issue for runtime PM. Something like this will be
needed to prevent the controller from autosuspending while waiting for
a root-hub resume to take place. (That is, in fact, the common case,
for which there is an extra test.)Signed-off-by: Alan Stern
Signed-off-by: Greg Kroah-Hartman -
This patch (as1385) adds a "do_wakeup" parameter to the pci_suspend
method used by PCI-based host controller drivers. ehci-hcd in
particular needs to know whether or not to enable wakeup when
suspending a controller. Although that information is currently
available through device_may_wakeup(), when support is added for
runtime suspend this will no longer be true.Signed-off-by: Alan Stern
Signed-off-by: Greg Kroah-Hartman -
This patch (as1393) converts several of the single-bit fields in
struct usb_hcd to atomic flags. This is for safety's sake; not all
CPUs can update bitfield values atomically, and these flags are used
in multiple contexts.The flag fields that are set only during registration or removal can
remain as they are, since non-atomic accesses at those times will not
cause any problems.(Strictly speaking, the authorized_default flag should become atomic
as well. I didn't bother with it because it gets changed only via
sysfs. It can be done later, if anyone wants.)Signed-off-by: Alan Stern
Signed-off-by: Greg Kroah-Hartman -
Added a disconnect() callback to composite devices which
is called by composite glue when its disconnect callback
is called by gadget.Signed-off-by: Michal Nazarewicz
Signed-off-by: Kyungmin Park
Acked-by: David Brownell
Signed-off-by: Greg Kroah-Hartman -
usb_string_ids_tab() and usb_string_ids_n() functions added to
the composite framework. The first accepts an array of
usb_string object and for each registeres a string id and the
second registeres a given number of ids and returns the first.This may simplify string ids registration since gadgets and
composite functions won't have to call usb_string_id() several
times and each time check for errer status -- all this will be
done with a single call.Signed-off-by: Michal Nazarewicz
Signed-off-by: Kyungmin Park
Signed-off-by: Greg Kroah-Hartman -
FunctionFS had a bit unique name for function used to add it
to USB configuration. Renamed as to match naming convention
of other functions.Signed-off-by: Michal Nazarewicz
Signed-off-by: Kyungmin Park
Signed-off-by: Greg Kroah-Hartman -
And audit all the users. None needed the BKL. That was easy
because there was only very few around.Tested with allmodconfig build on x86-64
Signed-off-by: Andi Kleen
Cc: Arnd Bergmann
From: Andi Kleen -
With this patch, the LPM capable EHCI host controller can put device
into L1 sleep state which is a mode that can enter/exit quickly, and
reduce power consumption.Signed-off-by: Jacob Pan
Signed-off-by: Alek Du
Signed-off-by: Greg Kroah-Hartman -
EHCI 1.1 addendum introduced several energy efficiency extensions for
EHCI USB host controllers:
1. LPM (link power management)
2. Per-port change
3. Shorter periodic frame list
4. Hardware prefetchingThis patch is intended to define the HW bits and debug interface for
EHCI 1.1 addendum. The LPM and Per-port change patches will be sent out
after this patch.Signed-off-by: Jacob Pan
Signed-off-by: Alek Du
Signed-off-by: Greg Kroah-Hartman -
otg_io_write() function does not follow the declaration of
struct otg_io_access_ops.Signed-off-by: Igor Grinberg
Signed-off-by: Greg Kroah-Hartman -
This patch (as1390) fixes a problem that crops up when a UHCI host
controller is unbound from uhci-hcd while there are still some active
URBs. The URBs have to be unlinked when the root hub is unregistered,
and uhci-hcd relies upon root-hub status polls as part of its
unlinking procedure. But usb_hcd_poll_rh_status() won't make those
status calls if hcd->rh_registered is clear, and the flag is cleared
_before_ the unregistration takes place.Since hcd->rh_registered is used for other things and needs to be
cleared early, the solution is to add a new flag (rh_pollable) and use
it instead. It gets cleared _after_ the root hub is unregistered.Now that the status polls don't end too soon, we have to make sure
they also don't occur too late -- after the root hub's usb_device
structure or the HCD's private structures are deallocated. Therefore
the patch adds usb_get_device() and usb_put_device() calls to protect
the root hub structure, and it adds an extra del_timer_sync() to
prevent the root-hub timer from causing an unexpected status poll.This additional complexity would not be needed if the HCD framework
had provided separate stop() and release() callbacks instead of just
stop(). This lack could be fixed at some future time (although it
would require changes to every host controller driver); when that
happens this patch won't be needed any more.Signed-off-by: Alan Stern
Signed-off-by: Greg Kroah-Hartman -
* 'writable_limits' of git://decibel.fi.muni.cz/~xslaby/linux:
unistd: add __NR_prlimit64 syscall numbers
rlimits: implement prlimit64 syscall
rlimits: switch more rlimit syscalls to do_prlimit
rlimits: redo do_setrlimit to more generic do_prlimit
rlimits: add rlimit64 structure
rlimits: do security check under task_lock
rlimits: allow setrlimit to non-current tasks
rlimits: split sys_setrlimit
rlimits: selinux, do rlimits changes under task_lock
rlimits: make sure ->rlim_max never grows in sys_setrlimit
rlimits: add task_struct to update_rlimit_cpu
rlimits: security, add task_struct to setrlimitFix up various system call number conflicts. We not only added fanotify
system calls in the meantime, but asm-generic/unistd.h added a wait4
along with a range of reserved per-architecture system calls. -
* git://git.infradead.org/mtd-2.6: (79 commits)
mtd: Remove obsolete include
mtd: Update copyright notices
jffs2: Update copyright notices
mtd-physmap: add support users can assign the probe type in board files
mtd: remove redwood map driver
mxc_nand: Add v3 (i.MX51) Support
mxc_nand: support 8bit ecc
mxc_nand: fix correct_data function
mxc_nand: add V1_V2 namespace to registers
mxc_nand: factor out a check_int function
mxc_nand: make some internally used functions overwriteable
mxc_nand: rework get_dev_status
mxc_nand: remove 0xe00 offset from registers
mtd: denali: Add multi connected NAND support
mtd: denali: Remove set_ecc_config function
mtd: denali: Remove unuseful code in get_xx_nand_para functions
mtd: denali: Remove device_info_tag structure
mtd: m25p80: add support for the Winbond W25Q32 SPI flash chip
mtd: m25p80: add support for the Intel/Numonyx {16,32,64}0S33B SPI flash chips
mtd: m25p80: add support for the EON EN25P{32, 64} SPI flash chips
...Fix up trivial conflicts in drivers/mtd/maps/{Kconfig,redwood.c} due to
redwood driver removal. -
* 'for-linus' of git://git.infradead.org/users/eparis/notify: (132 commits)
fanotify: use both marks when possible
fsnotify: pass both the vfsmount mark and inode mark
fsnotify: walk the inode and vfsmount lists simultaneously
fsnotify: rework ignored mark flushing
fsnotify: remove global fsnotify groups lists
fsnotify: remove group->mask
fsnotify: remove the global masks
fsnotify: cleanup should_send_event
fanotify: use the mark in handler functions
audit: use the mark in handler functions
dnotify: use the mark in handler functions
inotify: use the mark in handler functions
fsnotify: send fsnotify_mark to groups in event handling functions
fsnotify: Exchange list heads instead of moving elements
fsnotify: srcu to protect read side of inode and vfsmount locks
fsnotify: use an explicit flag to indicate fsnotify_destroy_mark has been called
fsnotify: use _rcu functions for mark list traversal
fsnotify: place marks on object in order of group memory address
vfs/fsnotify: fsnotify_close can delay the final work in fput
fsnotify: store struct file not struct path
...Fix up trivial delete/modify conflict in fs/notify/inotify/inotify.c.
-
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (96 commits)
no need for list_for_each_entry_safe()/resetting with superblock list
Fix sget() race with failing mount
vfs: don't hold s_umount over close_bdev_exclusive() call
sysv: do not mark superblock dirty on remount
sysv: do not mark superblock dirty on mount
btrfs: remove junk sb_dirt change
BFS: clean up the superblock usage
AFFS: wait for sb synchronization when needed
AFFS: clean up dirty flag usage
cifs: truncate fallout
mbcache: fix shrinker function return value
mbcache: Remove unused features
add f_flags to struct statfs(64)
pass a struct path to vfs_statfs
update VFS documentation for method changes.
All filesystems that need invalidate_inode_buffers() are doing that explicitly
convert remaining ->clear_inode() to ->evict_inode()
Make ->drop_inode() just return whether inode needs to be dropped
fs/inode.c:clear_inode() is gone
fs/inode.c:evict() doesn't care about delete vs. non-delete paths now
...Fix up trivial conflicts in fs/nilfs2/super.c
10 Aug, 2010
21 commits
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* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (59 commits)
igbvf.txt: Add igbvf Documentation
igb.txt: Add igb documentation
e100/e1000*/igb*/ixgb*: Add missing read memory barrier
ixgbe: fix build error with FCOE_CONFIG without DCB_CONFIG
netxen: protect tx timeout recovery by rtnl lock
isdn: gigaset: use after free
isdn: gigaset: add missing unlock
solos-pci: Fix race condition in tasklet RX handling
pkt_sched: Fix sch_sfq vs tcf_bind_filter oops
net: disable preemption before call smp_processor_id()
tcp: no md5sig option size check bug
iwlwifi: fix locking assertions
iwlwifi: fix TX tracer
isdn: fix information leak
net: Fix napi_gro_frags vs netpoll path
usbnet: remove noisy and hardly useful printk
rtl8180: avoid potential NULL deref in rtl8180_beacon_work
ath9k: Remove myself from the MAINTAINERS list
libertas: scan before assocation if no BSSID was given
libertas: fix association with some APs by using extended rates
... -
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (30 commits)
DMAENGINE: at_hdmac: locking fixlet
DMAENGINE: pch_dma: kill another usage of __raw_{read|write}l
dma: dmatest: fix potential sign bug
ioat2: catch and recover from broken vtd configurations v6
DMAENGINE: add runtime slave control to COH 901 318 v3
DMAENGINE: add runtime slave config to DMA40 v3
DMAENGINE: generic slave channel control v3
dmaengine: Driver for Topcliff PCH DMA controller
intel_mid: Add Mrst & Mfld DMA Drivers
drivers/dma: Eliminate a NULL pointer dereference
dma/timb_dma: compile warning on 32 bit
DMAENGINE: ste_dma40: support older silicon
DMAENGINE: ste_dma40: support disabling physical channels
DMAENGINE: ste_dma40: no disabled phy channels on ux500
DMAENGINE: ste_dma40: fix suspend bug
DMAENGINE: ste_dma40: add DB8500 memcpy channels
DMAENGINE: ste_dma40: no flow control on memcpy
DMAENGINE: ste_dma40: arch updates for LCLA and LCPA
DMAENGINE: ste_dma40: allocate LCLA dynamically
DMAENGINE: ste_dma40: no premature stop
...Fix up trivial conflicts in arch/arm/mach-ux500/devices-db8500.c
-
Getting and putting arrays of pointers with flex arrays is a PITA. You
have to remember to pass &ptr to the _put and you have to do weird and
wacky casting to get the ptr back from the _get. Add two functions
flex_array_get_ptr() and flex_array_put_ptr() to handle all of the magic.[akpm@linux-foundation.org: simplification suggested by Joe]
Signed-off-by: Eric Paris
Cc: David Rientjes
Cc: Dave Hansen
Cc: Joe Perches
Cc: James Morris
Cc: Joe Perches
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 -
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 -
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 -
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 -
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 -
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 -
Since 2.6.28 zone->prev_priority is unused. Then it can be removed
safely. It reduce stack usage slightly.Now I have to say that I'm sorry. 2 years ago, I thought prev_priority
can be integrate again, it's useful. but four (or more) times trying
haven't got good performance number. Thus I give up such approach.The rest of this changelog is notes on prev_priority and why it existed in
the first place and why it might be not necessary any more. This information
is based heavily on discussions between Andrew Morton, Rik van Riel and
Kosaki Motohiro who is heavily quotes from.Historically prev_priority was important because it determined when the VM
would start unmapping PTE pages. i.e. there are no balances of note within
the VM, Anon vs File and Mapped vs Unmapped. Without prev_priority, there
is a potential risk of unnecessarily increasing minor faults as a large
amount of read activity of use-once pages could push mapped pages to the
end of the LRU and get unmapped.There is no proof this is still a problem but currently it is not considered
to be. Active files are not deactivated if the active file list is smaller
than the inactive list reducing the liklihood that file-mapped pages are
being pushed off the LRU and referenced executable pages are kept on the
active list to avoid them getting pushed out by read activity.Even if it is a problem, prev_priority prev_priority wouldn't works
nowadays. First of all, current vmscan still a lot of UP centric code. it
expose some weakness on some dozens CPUs machine. I think we need more and
more improvement.The problem is, current vmscan mix up per-system-pressure, per-zone-pressure
and per-task-pressure a bit. example, prev_priority try to boost priority to
other concurrent priority. but if the another task have mempolicy restriction,
it is unnecessary, but also makes wrong big latency and exceeding reclaim.
per-task based priority + prev_priority adjustment make the emulation of
per-system pressure. but it have two issue 1) too rough and brutal emulation
2) we need per-zone pressure, not per-system.Another example, currently DEF_PRIORITY is 12. it mean the lru rotate about
2 cycle (1/4096 + 1/2048 + 1/1024 + .. + 1) before invoking OOM-Killer.
but if 10,0000 thrreads enter DEF_PRIORITY reclaim at the same time, the
system have higher memory pressure than priority==0 (1/4096*10,000 > 2).
prev_priority can't solve such multithreads workload issue. In other word,
prev_priority concept assume the sysmtem don't have lots threads."Signed-off-by: KOSAKI Motohiro
Signed-off-by: Mel Gorman
Reviewed-by: Johannes Weiner
Reviewed-by: Rik van Riel
Cc: Dave Chinner
Cc: Chris Mason
Cc: Nick Piggin
Cc: Rik van Riel
Cc: Johannes Weiner
Cc: Christoph Hellwig
Cc: KAMEZAWA Hiroyuki
Cc: KOSAKI Motohiro
Cc: Andrea Arcangeli
Cc: Michael Rubin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add a trace event for when page reclaim queues a page for IO and records
whether it is synchronous or asynchronous. Excessive synchronous IO for a
process can result in noticeable stalls during direct reclaim. Excessive
IO from page reclaim may indicate that the system is seriously under
provisioned for the amount of dirty pages that exist.Signed-off-by: Mel Gorman
Acked-by: Rik van Riel
Acked-by: Larry Woodman
Cc: Dave Chinner
Cc: Chris Mason
Cc: Nick Piggin
Cc: Rik van Riel
Cc: Johannes Weiner
Cc: Christoph Hellwig
Cc: KAMEZAWA Hiroyuki
Cc: KOSAKI Motohiro
Cc: Andrea Arcangeli
Cc: Michael Rubin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add an event for when pages are isolated en-masse from the LRU lists.
This event augments the information available on LRU traffic and can be
used to evaluate lumpy reclaim.[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mel Gorman
Acked-by: Rik van Riel
Acked-by: Larry Woodman
Cc: Dave Chinner
Cc: Chris Mason
Cc: Nick Piggin
Cc: Rik van Riel
Cc: Johannes Weiner
Cc: Christoph Hellwig
Cc: KAMEZAWA Hiroyuki
Cc: KOSAKI Motohiro
Cc: Andrea Arcangeli
Cc: Michael Rubin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add two trace events for kswapd waking up and going asleep for the
purposes of tracking kswapd activity and two trace events for direct
reclaim beginning and ending. The information can be used to work out how
much time a process or the system is spending on the reclamation of pages
and in the case of direct reclaim, how many pages were reclaimed for that
process. High frequency triggering of these events could point to memory
pressure problems.Signed-off-by: Mel Gorman
Acked-by: Rik van Riel
Acked-by: Larry Woodman
Cc: Dave Chinner
Cc: Chris Mason
Cc: Nick Piggin
Cc: Rik van Riel
Cc: Johannes Weiner
Cc: Christoph Hellwig
Cc: KAMEZAWA Hiroyuki
Cc: KOSAKI Motohiro
Cc: Andrea Arcangeli
Cc: Michael Rubin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
