It is possible for fbq_classify_rq() to indicate that a CPU has tasks that
should be moved to another NUMA node, but for migrate_improves_locality
and migrate_degrades_locality to not identify those tasks.
This patch always gives preference to preferred node evaluations, and
only checks the number of faults when evaluating moves between two
non-preferred nodes on a larger NUMA system.
On a two node system, the number of faults is never evaluated. Either
a task is about to be pulled off its preferred node, or migrated onto
it.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: mgorman@suse.de
Link: http://lkml.kernel.org/r/20150514225936.35b91717@annuminas.surriel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently people use TASK_INTERRUPTIBLE to idle kthreads and wait for
'work' because TASK_UNINTERRUPTIBLE contributes to the loadavg. Having
all idle kthreads contribute to the loadavg is somewhat silly.
Now mostly this works OK, because kthreads have all their signals
masked. However there's a few sites where this is causing problems and
TASK_UNINTERRUPTIBLE should be used, except for that loadavg issue.
This patch adds TASK_NOLOAD which, when combined with
TASK_UNINTERRUPTIBLE avoids the loadavg accounting.
As most of imagined usage sites are loops where a thread wants to
idle, waiting for work, a helper TASK_IDLE is introduced.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Julian Anastasov <ja@ssi.bg>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: NeilBrown <neilb@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit 662bbcb274 ("mm, sched: Allow uaccess in atomic with
pagefault_disable()") removed might_sleep() checks for all user access
code (that uses might_fault()).
The reason was to disable wrong "sleep in atomic" warnings in the
following scenario:
pagefault_disable()
rc = copy_to_user(...)
pagefault_enable()
Which is valid, as pagefault_disable() increments the preempt counter
and therefore disables the pagefault handler. copy_to_user() will not
sleep and return an error code if a page is not available.
However, as all might_sleep() checks are removed,
CONFIG_DEBUG_ATOMIC_SLEEP would no longer detect the following scenario:
spin_lock(&lock);
rc = copy_to_user(...)
spin_unlock(&lock)
If the kernel is compiled with preemption turned on, preempt_disable()
will make in_atomic() detect disabled preemption. The fault handler would
correctly never sleep on user access.
However, with preemption turned off, preempt_disable() is usually a NOP
(with !CONFIG_PREEMPT_COUNT), therefore in_atomic() will not be able to
detect disabled preemption nor disabled pagefaults. The fault handler
could sleep.
We really want to enable CONFIG_DEBUG_ATOMIC_SLEEP checks for user access
functions again, otherwise we can end up with horrible deadlocks.
Root of all evil is that pagefault_disable() acts almost as
preempt_disable(), depending on preemption being turned on/off.
As we now have pagefault_disabled(), we can use it to distinguish
whether user acces functions might sleep.
Convert might_fault() into a makro that calls __might_fault(), to
allow proper file + line messages in case of a might_sleep() warning.
Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-3-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
preempt_mask.h defines all the preempt_count semantics and related
symbols: preempt, softirq, hardirq, nmi, preempt active, need resched,
etc...
preempt.h defines the accessors and mutators of preempt_count.
But there is a messy dependency game around those two header files:
* preempt_mask.h includes preempt.h in order to access preempt_count()
* preempt_mask.h defines all preempt_count semantic and symbols
except PREEMPT_NEED_RESCHED that is needed by asm/preempt.h
Thus we need to define it from preempt.h, right before including
asm/preempt.h, instead of defining it to preempt_mask.h with the
other preempt_count symbols. Therefore the preempt_count semantics
happen to be spread out.
* We plan to introduce preempt_active_[enter,exit]() to consolidate
preempt_schedule*() code. But we'll need to access both preempt_count
mutators (preempt_count_add()) and preempt_count symbols
(PREEMPT_ACTIVE, PREEMPT_OFFSET). The usual place to define preempt
operations is in preempt.h but then we'll need symbols in
preempt_mask.h which already includes preempt.h. So we end up with
a ressource circle dependency.
Lets merge preempt_mask.h into preempt.h to solve these dependency issues.
This way we gather semantic symbols and operation definition of
preempt_count in a single file.
This is a dumb copy-paste merge. Further merge re-arrangments are
performed in a subsequent patch to ease review.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1431441711-29753-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Two watchdog changes that came through different trees had a non
conflicting conflict, that is, one changed the semantics of a variable
but no actual code conflict happened. So the merge appeared fine, but
the resulting code did not behave as expected.
Commit 195daf665a ("watchdog: enable the new user interface of the
watchdog mechanism") changes the semantics of watchdog_user_enabled,
which thereafter is only used by the functions introduced by
b3738d2932 ("watchdog: Add watchdog enable/disable all functions").
There further appears to be a distinct lack of serialization between
setting and using watchdog_enabled, so perhaps we should wrap the
{en,dis}able_all() things in watchdog_proc_mutex.
This patch fixes a s2r failure reported by Michal; which I cannot
readily explain. But this does make the code internally consistent
again.
Reported-and-tested-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull MTD fixes from Brian Norris:
"Two MTD fixes for 4.1:
- readtest: the signal-handling code was clobbering the error codes
we should be handling/reporting in this test, rendering it useless.
Noticed by Coverity.
- the common SPI NOR flash DT binding (merged for 4.1-rc1) is being
revised, so let's change that before 4.1 is minted"
* tag 'for-linus-20150516' of git://git.infradead.org/linux-mtd:
Documentation: dt: mtd: replace "nor-jedec" binding with "jedec, spi-nor"
mtd: readtest: don't clobber error reports
static code checking was unhappy with:
./kernel/sched/fair.c:162 WARNING: return of wrong type
int != unsigned int
get_update_sysctl_factor() is declared to return int but is
currently returning an unsigned int. The first few preprocessed
lines are:
static int get_update_sysctl_factor(void)
{
unsigned int cpus = ({ int __min1 = (cpumask_weight(cpu_online_mask));
int __min2 = (8); __min1 < __min2 ? __min1: __min2; });
unsigned int factor;
The type used by min_t() should be 'unsigned int' and the return type
of get_update_sysctl_factor() should also be 'unsigned int' as its
call-site update_sysctl() is expecting 'unsigned int' and the values
utilizing:
'factor'
'sysctl_sched_min_granularity'
'sched_nr_latency'
'sysctl_sched_wakeup_granularity'
... are also all 'unsigned int', plus cpumask_weight() is also
returning 'unsigned int'.
So the natural type to use around here is 'unsigned int'.
( Patch was compile tested with x86_64_defconfig +
CONFIG_SCHED_DEBUG=y and the changed sections in
kernel/sched/fair.i were reviewed. )
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
[ Improved the changelog a bit. ]
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1431716742-11077-1-git-send-email-hofrat@osadl.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull USB fixes from Greg KH:
"Here are some USB fixes and new device ids for 4.1-rc4.
All are pretty minor, and have been in linux-next successfully"
* tag 'usb-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb-storage: Add NO_WP_DETECT quirk for Lacie 059f:0651 devices
Added another USB product ID for ELAN touchscreen quirks.
xhci: gracefully handle xhci_irq dead device
xhci: Solve full event ring by increasing TRBS_PER_SEGMENT to 256
xhci: fix isoc endpoint dequeue from advancing too far on transaction error
usb: chipidea: debug: avoid out of bound read
USB: visor: Match I330 phone more precisely
USB: pl2303: Remove support for Samsung I330
USB: cp210x: add ID for KCF Technologies PRN device
usb: gadget: remove incorrect __init/__exit annotations
usb: phy: isp1301: work around tps65010 dependency
usb: gadget: serial: fix re-ordering of tx data
usb: gadget: hid: Fix static variable usage
usb: gadget: configfs: Fix interfaces array NULL-termination
usb: gadget: xilinx: fix devm_ioremap_resource() check
usb: dwc3: dwc3-omap: correct the register macros
Pull tty/serial fixes from Greg KH:
"Here's some TTY and serial driver fixes for reported issues.
All of these have been in linux-next successfully"
* tag 'tty-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
pty: Fix input race when closing
tty/n_gsm.c: fix a memory leak when gsmtty is removed
Revert "serial/amba-pl011: Leave the TX IRQ alone when the UART is not open"
serial: omap: Fix error handling in probe
earlycon: Revert log warnings
Pull staging / IIO driver fixes from Greg KH:
"Here's some staging and iio driver fixes to resolve a number of
reported issues.
All of these have been in linux-next for a while"
* tag 'staging-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (31 commits)
iio: light: hid-sensor-prox: Fix memory leak in probe()
iio: adc: cc10001: Add delay before setting START bit
iio: adc: cc10001: Fix regulator_get_voltage() return value check
iio: adc: cc10001: Fix incorrect use of power-up/power-down register
staging: gdm724x: Correction of variable usage after applying ALIGN()
iio: adc: cc10001: Fix the channel number mapping
staging: vt6655: lock MACvWriteBSSIDAddress.
staging: vt6655: CARDbUpdateTSF bss timestamp correct tsf counter value.
staging: vt6655: vnt_tx_packet Correct TX order of OWNED_BY_NIC
staging: vt6655: Fix 80211 control and management status reporting.
staging: vt6655: implement IEEE80211_TX_STAT_NOACK_TRANSMITTED
staging: vt6655: device_free_tx_buf use only ieee80211_tx_status_irqsafe
staging: vt6656: use ieee80211_tx_info to select packet type.
staging: rtl8712: freeing an ERR_PTR
staging: sm750: remove incorrect __exit annotation
iio: kfifo: Set update_needed to false only if a buffer was allocated
iio: mcp320x: Fix occasional incorrect readings
iio: accel: mma9553: check input value for activity period
iio: accel: mma9553: add enable channel for activity
iio: accel: mma9551_core: prevent buffer overrun
...
Pull char/misc fix from Greg KH:
"Here is one fix, in the extcon subsystem, that resolves a reported
issue.
It's been in linux-next for a number of weeks now, sorry for not
getting it to you sooner"
* tag 'char-misc-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
extcon: usb-gpio: register extcon device before IRQ registration
Pull UML hostfs fix from Richard Weinberger:
"This contains a single fix for a regression introduced in 4.1-rc1"
* 'for-linus-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
hostfs: Use correct mask for file mode
Pull UBI bufix from Richard Weinberger:
"This contains a single bug fix for the UBI block driver"
* tag 'upstream-4.1-rc4' of git://git.infradead.org/linux-ubifs:
UBI: block: Add missing cache flushes
Pull ext4 fixes from Ted Ts'o:
"Fix a number of ext4 bugs; the most serious of which is a bug in the
lazytime mount optimization code where we could end up updating the
timestamps to the wrong inode"
* tag 'for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix an ext3 collapse range regression in xfstests
jbd2: fix r_count overflows leading to buffer overflow in journal recovery
ext4: check for zero length extent explicitly
ext4: fix NULL pointer dereference when journal restart fails
ext4: remove unused function prototype from ext4.h
ext4: don't save the error information if the block device is read-only
ext4: fix lazytime optimization
Pull btrfs fixes from Chris Mason:
"The first commit is a fix from Filipe for a very old extent buffer
reuse race that triggered a BUG_ON. It hasn't come up often, I looked
through old logs at FB and we hit it a handful of times over the last
year.
The rest are other corners he hit during testing"
* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix race when reusing stale extent buffers that leads to BUG_ON
Btrfs: fix race between block group creation and their cache writeout
Btrfs: fix panic when starting bg cache writeout after IO error
Btrfs: fix crash after inode cache writeback failure
Pull MIPS fixes from Ralf Baechle:
"Seven small fixes. The shortlog below is a good description so no
need to elaborate.
It has sat in linux-next and survived the usual automated testing by
Imagination's test farm"
* 'master' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
MIPS: tlb-r4k: Fix PG_ELPA comment
MIPS: Fix up obsolete cpu_set usage
MIPS: IP32: Fix build errors in reset code in DS1685 platform hook.
MIPS: KVM: Fix unused variable build warning
MIPS: traps: remove extra Tainted: line from __show_regs() output
MIPS: Fix wrong CHECKFLAGS (sparse builds) with GCC 5.1
MIPS: Fix a preemption issue with thread's FPU defaults
Pull ARM SoC fixes from Arnd Bergmann:
"Nothing frightening this time, just smaller fixes in a number of
places.
The other changes contained here are:
MAINTAINERS file updates:
- The mach-gemini maintainer is back in action and has a new git tree
- Krzysztof Kozlowski has volunteered to be a new co-maintainer for
the samsung platforms
- updates to the files that belong to Marvell mvebu
Bug fixes:
- The largest changes are on omap2, but are only to avoid some
harmless warnings and to fix reset on omap4
- a small regression fix on tegra
- multiple fixes for incorrect IRQ affinity on vexpress
- the missing system controller on arm64 juno is added
- one revert of a patch that was accidentally applied twice for
mach-rockchip
- two clock related DT fixes for mvebu
- a workaround for suspend with old DT binaries on new exynos kernels
- Another fix for suspend on exynos, needs to be backported"
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (21 commits)
MAINTAINERS: Add dts entries for some of the Marvell SoCs
MAINTAINERS: ARM: EXYNOS: Add Krzysztof Kozlowski as co-maintainer
ARM: EXYNOS: Use of_machine_is_compatible instead of soc_is_exynos4
ARM: EXYNOS: Fix failed second suspend on Exynos4
Revert "ARM: rockchip: fix undefined instruction of reset_ctrl_regs"
ARM: EXYNOS: Fix dereference of ERR_PTR returned by of_genpd_get_from_provider
ARM: EXYNOS: Don't try to initialize suspend on old DT
ARM: dts: Add keep-power-in-suspend to WiFi SDIO node for Peach Boards
ARM: gemini: fix compiler warning due wrong data type
ARM: vexpress/tc2: Add interrupt-affinity to the PMU node
ARM: vexpress/ca9: Add interrupt-affinity to the PMU node
ARM: vexpress/ca9: Add unified-cache property to l2 cache node
ARM64: juno: add sp810 support and fix sp804 clock frequency
ARM: Gemini: Maintainers update
ARM: OMAP2+: Remove bogus struct clk comparison for timer clock
ARM: dove: Add clock-names to CuBox Si5351 clk generator
ARM: AM33xx+: hwmod: re-use omap4 implementations for reset functionality
ARM: OMAP4+: PRM: add support for passing status register/bit info to reset
ARM: AM43xx: hwmod: add VPFE hwmod entries
ARM: mvebu: Fix the main PLL frequency on Armada 375, 38x and 39x SoCs
...
