HZ is more likely to be 1000 these days.
timer handlers are run from softirq, no need to disable bh
skb priority 1 is TC_PRIO_FILLER
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Name string overrun fix in gianfar driver from Joe Perches.
2) VHOST bug fixes from Michael S. Tsirkin and Nadav Har'El
3) Fix dependencies on xt_LOG netfilter module, from Pablo Neira Ayuso.
4) Fix RCU locking in xt_CT, also from Pablo Neira Ayuso.
5) Add a parameter to skb_add_rx_frag() so we can fix the truesize
adjustments in the drivers that use it. The individual drivers
aren't fixed by this commit, but will be dealt with using follow-on
commits. From Eric Dumazet.
6) Add some device IDs to qmi_wwan driver, from Andrew Bird.
7) Fix a potential rcu_read_lock() imbalancein rt6_fill_node(). From
Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
net: fix a potential rcu_read_lock() imbalance in rt6_fill_node()
net: add a truesize parameter to skb_add_rx_frag()
gianfar: Fix possible overrun and simplify interrupt name field creation
USB: qmi_wwan: Add ZTE (Vodafone) K3570-Z and K3571-Z net interfaces
USB: option: Ignore ZTE (Vodafone) K3570/71 net interfaces
USB: qmi_wwan: Add ZTE (Vodafone) K3565-Z and K4505-Z net interfaces
qlcnic: Bug fix for LRO
netfilter: nf_conntrack: permanently attach timeout policy to conntrack
netfilter: xt_CT: fix assignation of the generic protocol tracker
netfilter: xt_CT: missing rcu_read_lock section in timeout assignment
netfilter: cttimeout: fix dependency with l4protocol conntrack module
netfilter: xt_LOG: use CONFIG_IP6_NF_IPTABLES instead of CONFIG_IPV6
vhost: fix release path lockdep checks
vhost: don't forget to schedule()
tools/virtio: stub out strong barriers
tools/virtio: add linux/hrtimer.h stub
tools/virtio: add linux/module.h stub
Pull "ARM: device tree work" from Arnd Bergmann:
"Most of these patches convert code from using static platform data to
describing the hardware in the device tree. This is only the first
half of the changes for v3.4 because a lot of patches for this topic
came in the last week before the merge window.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>"
Fix up trivial conflicts in arch/arm/mach-vexpress/{Kconfig,core.h}
* tag 'dt' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (86 commits)
Document: devicetree: add OF documents for arch-mmp
ARM: dts: append DTS file of pxa168
ARM: mmp: append OF support on pxa168
ARM: mmp: enable rtc clk in pxa168
i2c: pxa: add OF support
serial: pxa: add OF support
arm/dts: mt_ventoux: very basic support for TeeJet Mt.Ventoux board
ARM: OMAP2+: Remove extra ifdefs for board-generic
ARM: OMAP2+: Fix build error when only ARCH_OMAP2/3 or 4 is selected
ASoC: DT: Add digital microphone binding to PAZ00 board.
ARM: dt: Add ARM PMU to tegra*.dtsi
ARM: at91: at91sam9x5cm/dt: add leds support
ARM: at91: usb_a9g20/dt: add gpio-keys support
ARM: at91: at91sam9m10g45ek/dt: add gpio-keys support
ARM: at91: at91sam9m10g45ek/dt: add leds support
ARM: at91: usb_a9g20/dt: add leds support
ARM: at91/pio: add new PIO3 features
ARM: at91: add sam9_smc.o to at91sam9x5 build
ARM: at91/tc/clocksource: Add 32 bit variant to Timer Counter
ARM: at91/tc: add device tree support to atmel_tclib
...
Pull "ARM: driver specific updates" from Arnd Bergmann:
"These are all specific to some driver. They are typically the
platform side of a change in the drivers directory, such as adding a
new driver or extending the interface to the platform. In cases where
there is no maintainer for the driver, or the maintainer prefers to
have the platform changes in the same branch as the driver changes,
the patches to the drivers are included as well.
A much smaller set of driver updates that depend on other branches
getting merged first will be sent later.
The new export of tegra_chip_uid conflicts with other changes in
fuse.c. In rtc-sa1100.c, the global removal of IRQF_DISABLED
conflicts with the cleanup of the interrupt handling of that driver.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>"
Fixed up aforementioned trivial conflicts.
* tag 'drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (94 commits)
ARM: SAMSUNG: change the name from s3c-sdhci to exynos4-sdhci
mmc: sdhci-s3c: add platform data for the second capability
ARM: SAMSUNG: support the second capability for samsung-soc
ARM: EXYNOS: add support DMA for EXYNOS4X12 SoC
ARM: EXYNOS: Add apb_pclk clkdev entry for mdma1
ARM: EXYNOS: Enable MDMA driver
regulator: Remove bq24022 regulator driver
rtc: sa1100: add OF support
pxa: magician/hx4700: Convert to gpio-regulator from bq24022
ARM: OMAP3+: SmartReflex: fix error handling
ARM: OMAP3+: SmartReflex: fix the use of debugfs_create_* API
ARM: OMAP3+: SmartReflex: micro-optimization for sanity check
ARM: OMAP3+: SmartReflex: misc cleanups
ARM: OMAP3+: SmartReflex: move late_initcall() closer to its argument
ARM: OMAP3+: SmartReflex: add missing platform_set_drvdata()
ARM: OMAP3+: hwmod: add SmartReflex IRQs
ARM: OMAP3+: SmartReflex: clear ERRCONFIG_VPBOUNDINTST only on a need
ARM: OMAP3+: SmartReflex: Fix status masking in ERRCONFIG register
ARM: OMAP3+: SmartReflex: Add a shutdown hook
ARM: OMAP3+: SmartReflex Class3: disable errorgen before disable VP
...
Conflicts:
arch/arm/mach-tegra/Makefile
arch/arm/mach-tegra/fuse.c
drivers/rtc/rtc-sa1100.c
Pull "remoteproc/rpmsg: new subsystem" from Arnd Bergmann:
"This new subsystem provides a common way to talk to secondary
processors on an SoC, e.g. a DSP, GPU or service processor, using
virtio as the transport. In the long run, it should replace a few
dozen vendor specific ways to do the same thing, which all never made
it into the upstream kernel. There is a broad agreement that rpmsg is
the way to go here and several vendors have started working on
replacing their own subsystems.
Two branches each add one virtio protocol number. Fortunately the
numbers were agreed upon in advance, so there are only context
changes.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>"
Fixed up trivial protocol number conflict due to the mentioned additions
next to each other.
* tag 'rpmsg' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (32 commits)
remoteproc: cleanup resource table parsing paths
remoteproc: remove the hardcoded vring alignment
remoteproc/omap: remove the mbox_callback limitation
remoteproc: remove the single rpmsg vdev limitation
remoteproc: safer boot/shutdown order
remoteproc: remoteproc_rpmsg -> remoteproc_virtio
remoteproc: resource table overhaul
rpmsg: fix build warning when dma_addr_t is 64-bit
rpmsg: fix published buffer length in rpmsg_recv_done
rpmsg: validate incoming message length before propagating
rpmsg: fix name service endpoint leak
remoteproc/omap: two Kconfig fixes
remoteproc: make sure we're parsing a 32bit firmware
remoteproc: s/big switch/lookup table/
remoteproc: bail out if firmware has different endianess
remoteproc: don't use virtio's weak barriers
rpmsg: rename virtqueue_add_buf_gfp to virtqueue_add_buf
rpmsg: depend on EXPERIMENTAL
remoteproc: depend on EXPERIMENTAL
rpmsg: add Kconfig menu
...
Conflicts:
include/linux/virtio_ids.h
Pull "ARM: timer cleanup work" from Arnd Bergmann:
"These are split out from the generic soc and driver updates because
there was a lot of conflicting work by multiple people. Marc Zyngier
worked on simplifying the "localtimer" interfaces, and some of the
platforms are touching the same code as they move to device tree based
booting.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>"
* tag 'timer' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (61 commits)
ARM: tegra: select USB_ULPI if USB is selected
arm/tegra: pcie: fix return value of function
ARM: ux500: fix compilation after local timer rework
ARM: shmobile: remove additional __io() macro use
ARM: local timers: make the runtime registration interface mandatory
ARM: local timers: convert MSM to runtime registration interface
ARM: local timers: convert exynos to runtime registration interface
ARM: smp_twd: remove old local timer interface
ARM: imx6q: convert to twd_local_timer_register() interface
ARM: highbank: convert to twd_local_timer_register() interface
ARM: ux500: convert to twd_local_timer_register() interface
ARM: shmobile: convert to twd_local_timer_register() interface
ARM: tegra: convert to twd_local_timer_register() interface
ARM: plat-versatile: convert to twd_local_timer_register() interface
ARM: OMAP4: convert to twd_local_timer_register() interface
ARM: smp_twd: add device tree support
ARM: smp_twd: add runtime registration support
ARM: local timers: introduce a new registration interface
ARM: smp_twd: make local_timer_stop a symbol instead of a #define
ARM: mach-shmobile: default to no earlytimer
...
Pull "ARM: global cleanups" from Arnd Bergmann:
"Quite a bit of code gets removed, and some stuff moved around, mostly
the old samsung s3c24xx stuff. There should be no functional changes
in this series otherwise. Some cleanups have dependencies on other
arm-soc branches and will be sent in the second round.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>"
Fixed up trivial conflicts mainly due to #include's being changes on
both sides.
* tag 'cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (121 commits)
ep93xx: Remove unnecessary includes of ep93xx-regs.h
ep93xx: Move EP93XX_SYSCON defines to SoC private header
ep93xx: Move crunch code to mach-ep93xx directory
ep93xx: Make syscon access functions private to SoC
ep93xx: Configure GPIO ports in core code
ep93xx: Move peripheral defines to local SoC header
ep93xx: Convert the watchdog driver into a platform device.
ep93xx: Use ioremap for backlight driver
ep93xx: Move GPIO defines to gpio-ep93xx.h
ep93xx: Don't use system controller defines in audio drivers
ep93xx: Move PHYS_BASE defines to local SoC header file
ARM: EXYNOS: Add clock register addresses for EXYNOS4X12 bus devfreq driver
ARM: EXYNOS: add clock registers for exynos4x12-cpufreq
PM / devfreq: update the name of EXYNOS clock registers that were omitted
PM / devfreq: update the name of EXYNOS clock register
ARM: EXYNOS: change the prefix S5P_ to EXYNOS4_ for clock
ARM: EXYNOS: use static declaration on regarding clock
ARM: EXYNOS: replace clock.c for other new EXYNOS SoCs
ARM: OMAP2+: Fix build error after merge
ARM: S3C24XX: remove call to s3c24xx_setup_clocks
...
skb_add_rx_frag() API is misleading.
Network skbs built with this helper can use uncharged kernel memory and
eventually stress/crash machine in OOM.
Add a 'truesize' parameter and then fix drivers in followup patches.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull <linux/device.h> avoidance patches from Paul Gortmaker:
"Nearly every subsystem has some kind of header with a proto like:
void foo(struct device *dev);
and yet there is no reason for most of these guys to care about the
sub fields within the device struct. This allows us to significantly
reduce the scope of headers including headers. For this instance, a
reduction of about 40% is achieved by replacing the include with the
simple fact that the device is some kind of a struct.
Unlike the much larger module.h cleanup, this one is simply two
commits. One to fix the implicit <linux/device.h> users, and then one
to delete the device.h includes from the linux/include/ dir wherever
possible."
* tag 'device-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
device.h: audit and cleanup users in main include dir
device.h: cleanup users outside of linux/include (C files)
Pull <linux/bug.h> cleanup from Paul Gortmaker:
"The changes shown here are to unify linux's BUG support under the one
<linux/bug.h> file. Due to historical reasons, we have some BUG code
in bug.h and some in kernel.h -- i.e. the support for BUILD_BUG in
linux/kernel.h predates the addition of linux/bug.h, but old code in
kernel.h wasn't moved to bug.h at that time. As a band-aid, kernel.h
was including <asm/bug.h> to pseudo link them.
This has caused confusion[1] and general yuck/WTF[2] reactions. Here
is an example that violates the principle of least surprise:
CC lib/string.o
lib/string.c: In function 'strlcat':
lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON'
make[2]: *** [lib/string.o] Error 1
$
$ grep linux/bug.h lib/string.c
#include <linux/bug.h>
$
We've included <linux/bug.h> for the BUG infrastructure and yet we
still get a compile fail! [We've not kernel.h for BUILD_BUG_ON.] Ugh -
very confusing for someone who is new to kernel development.
With the above in mind, the goals of this changeset are:
1) find and fix any include/*.h files that were relying on the
implicit presence of BUG code.
2) find and fix any C files that were consuming kernel.h and hence
relying on implicitly getting some/all BUG code.
3) Move the BUG related code living in kernel.h to <linux/bug.h>
4) remove the asm/bug.h from kernel.h to finally break the chain.
During development, the order was more like 3-4, build-test, 1-2. But
to ensure that git history for bisect doesn't get needless build
failures introduced, the commits have been reorderd to fix the problem
areas in advance.
[1] https://lkml.org/lkml/2012/1/3/90
[2] https://lkml.org/lkml/2012/1/17/414"
Fix up conflicts (new radeon file, reiserfs header cleanups) as per Paul
and linux-next.
* tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
kernel.h: doesn't explicitly use bug.h, so don't include it.
bug: consolidate BUILD_BUG_ON with other bug code
BUG: headers with BUG/BUG_ON etc. need linux/bug.h
bug.h: add include of it to various implicit C users
lib: fix implicit users of kernel.h for TAINT_WARN
spinlock: macroize assert_spin_locked to avoid bug.h dependency
x86: relocate get/set debugreg fcns to include/asm/debugreg.
The pxa regulator branch removes the bq24022 driver, while a lot of
other regulator drivers got added in the regulator tree. This
resolves the trivial conflicts by merging in the regulator patches
that are already merged into v3.4.
Conflicts:
drivers/regulator/Kconfig
drivers/regulator/Makefile
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Pull sysctl updates from Eric Biederman:
- Rewrite of sysctl for speed and clarity.
Insert/remove/Lookup in sysctl are all now O(NlogN) operations, and
are no longer bottlenecks in the process of adding and removing
network devices.
sysctl is now focused on being a filesystem instead of system call
and the code can all be found in fs/proc/proc_sysctl.c. Hopefully
this means the code is now approachable.
Much thanks is owed to Lucian Grinjincu for keeping at this until
something was found that was usable.
- The recent proc_sys_poll oops found by the fuzzer during hibernation
is fixed.
* git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl: (36 commits)
sysctl: protect poll() in entries that may go away
sysctl: Don't call sysctl_follow_link unless we are a link.
sysctl: Comments to make the code clearer.
sysctl: Correct error return from get_subdir
sysctl: An easier to read version of find_subdir
sysctl: fix memset parameters in setup_sysctl_set()
sysctl: remove an unused variable
sysctl: Add register_sysctl for normal sysctl users
sysctl: Index sysctl directories with rbtrees.
sysctl: Make the header lists per directory.
sysctl: Move sysctl_check_dups into insert_header
sysctl: Modify __register_sysctl_paths to take a set instead of a root and an nsproxy
sysctl: Replace root_list with links between sysctl_table_sets.
sysctl: Add sysctl_print_dir and use it in get_subdir
sysctl: Stop requiring explicit management of sysctl directories
sysctl: Add a root pointer to ctl_table_set
sysctl: Rewrite proc_sys_readdir in terms of first_entry and next_entry
sysctl: Rewrite proc_sys_lookup introducing find_entry and lookup_entry.
sysctl: Normalize the root_table data structure.
sysctl: Factor out insert_header and erase_header
...
Pull cpufreq updates for 3.4 from Dave Jones: new drivers and some fixes.
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
provide disable_cpufreq() function to disable the API.
EXYNOS5250: Add support cpufreq for EXYNOS5250
EXYNOS4X12: Add support cpufreq for EXYNOS4X12
[CPUFREQ] CPUfreq ondemand: update sampling rate without waiting for next sampling
[CPUFREQ] Add S3C2416/S3C2450 cpufreq driver
[CPUFREQ] Fix exposure of ARM_EXYNOS4210_CPUFREQ
[CPUFREQ] EXYNOS4210: update the name of EXYNOS clock register
[CPUFREQ] EXYNOS: Initialize locking_frequency with initial frequency
[CPUFREQ] s3c64xx: Fix mis-cherry pick of VDDINT
Fix up trivial conflicts in Kconfig and Makefile due to just changes
next to each other (OMAP2PLUS changes vs some new EXYNOS cpufreq
drivers).
Pull #2 ARM updates from Russell King:
"Further ARM AMBA primecell updates which aren't included directly in
the previous commit. I wanted to keep these separate as they're
touching stuff outside arch/arm/."
* 'amba' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7362/1: AMBA: Add module_amba_driver() helper macro for amba_driver
ARM: 7335/1: mach-u300: do away with MMC config files
ARM: 7280/1: mmc: mmci: Cache MMCICLOCK and MMCIPOWER register
ARM: 7309/1: realview: fix unconnected interrupts on EB11MP
ARM: 7230/1: mmc: mmci: Fix PIO read for small SDIO packets
ARM: 7227/1: mmc: mmci: Prepare for SDIO before setting up DMA job
ARM: 7223/1: mmc: mmci: Fixup use of runtime PM and use autosuspend
ARM: 7221/1: mmc: mmci: Change from using legacy suspend
ARM: 7219/1: mmc: mmci: Change vdd_handler to a generic ios_handler
ARM: 7218/1: mmc: mmci: Provide option to configure bus signal direction
ARM: 7217/1: mmc: mmci: Put power register deviations in variant data
ARM: 7216/1: mmc: mmci: Do not release spinlock in request_end
ARM: 7215/1: mmc: mmci: Increase max_segs from 16 to 128
Pull #1 ARM updates from Russell King:
"This one covers stuff which Arnd is waiting for me to push, as this is
shared between both our trees and probably other trees elsewhere.
Essentially, this contains:
- AMBA primecell device initializer updates - mostly shrinking the
size of the device declarations in platform code to something more
reasonable.
- Getting rid of the NO_IRQ crap from AMBA primecell stuff.
- Nicolas' idle cleanups. This in combination with the restart
cleanups from the last merge window results in a great many
mach/system.h files being deleted."
Yay: ~80 files, ~2000 lines deleted.
* 'for-armsoc' of git://git.linaro.org/people/rmk/linux-arm: (60 commits)
ARM: remove disable_fiq and arch_ret_to_user macros
ARM: make entry-macro.S depend on !MULTI_IRQ_HANDLER
ARM: rpc: make default fiq handler run-time installed
ARM: make arch_ret_to_user macro optional
ARM: amba: samsung: use common amba device initializers
ARM: amba: spear: use common amba device initializers
ARM: amba: nomadik: use common amba device initializers
ARM: amba: u300: use common amba device initializers
ARM: amba: lpc32xx: use common amba device initializers
ARM: amba: netx: use common amba device initializers
ARM: amba: bcmring: use common amba device initializers
ARM: amba: ep93xx: use common amba device initializers
ARM: amba: omap2: use common amba device initializers
ARM: amba: integrator: use common amba device initializers
ARM: amba: realview: get rid of private platform amba_device initializer
ARM: amba: versatile: get rid of private platform amba_device initializer
ARM: amba: vexpress: get rid of private platform amba_device initializer
ARM: amba: provide common initializers for static amba devices
ARM: amba: make use of -1 IRQs warn
ARM: amba: u300: get rid of NO_IRQ initializers
...
Merge second batch of patches from Andrew Morton:
- various misc things
- core kernel changes to prctl, exit, exec, init, etc.
- kernel/watchdog.c updates
- get_maintainer
- MAINTAINERS
- the backlight driver queue
- core bitops code cleanups
- the led driver queue
- some core prio_tree work
- checkpatch udpates
- largeish crc32 update
- a new poll() feature for the v4l guys
- the rtc driver queue
- fatfs
- ptrace
- signals
- kmod/usermodehelper updates
- coredump
- procfs updates
* emailed from Andrew Morton <akpm@linux-foundation.org>: (141 commits)
seq_file: add seq_set_overflow(), seq_overflow()
proc-ns: use d_set_d_op() API to set dentry ops in proc_ns_instantiate().
procfs: speed up /proc/pid/stat, statm
procfs: add num_to_str() to speed up /proc/stat
proc: speed up /proc/stat handling
fs/proc/kcore.c: make get_sparsemem_vmemmap_info() static
coredump: add VM_NODUMP, MADV_NODUMP, MADV_CLEAR_NODUMP
coredump: remove VM_ALWAYSDUMP flag
kmod: make __request_module() killable
kmod: introduce call_modprobe() helper
usermodehelper: ____call_usermodehelper() doesn't need do_exit()
usermodehelper: kill umh_wait, renumber UMH_* constants
usermodehelper: implement UMH_KILLABLE
usermodehelper: introduce umh_complete(sub_info)
usermodehelper: use UMH_WAIT_PROC consistently
signal: zap_pid_ns_processes: s/SEND_SIG_NOINFO/SEND_SIG_FORCED/
signal: oom_kill_task: use SEND_SIG_FORCED instead of force_sig()
signal: cosmetic, s/from_ancestor_ns/force/ in prepare_signal() paths
signal: give SEND_SIG_FORCED more power to beat SIGNAL_UNKILLABLE
Hexagon: use set_current_blocked() and block_sigmask()
...
Process accounting applications as top, ps visit some files under
/proc/<pid>. With seq_put_decimal_ull(), we can optimize /proc/<pid>/stat
and /proc/<pid>/statm files.
This patch adds
- seq_put_decimal_ll() for signed values.
- allow delimiter == 0.
- convert seq_printf() to seq_put_decimal_ull/ll in /proc/stat, statm.
Test result on a system with 2000+ procs.
Before patch:
[kamezawa@bluextal test]$ top -b -n 1 | wc -l
2223
[kamezawa@bluextal test]$ time top -b -n 1 > /dev/null
real 0m0.675s
user 0m0.044s
sys 0m0.121s
[kamezawa@bluextal test]$ time ps -elf > /dev/null
real 0m0.236s
user 0m0.056s
sys 0m0.176s
After patch:
kamezawa@bluextal ~]$ time top -b -n 1 > /dev/null
real 0m0.657s
user 0m0.052s
sys 0m0.100s
[kamezawa@bluextal ~]$ time ps -elf > /dev/null
real 0m0.198s
user 0m0.050s
sys 0m0.145s
Considering top, ps tend to scan /proc periodically, this will reduce cpu
consumption by top/ps to some extent.
[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
== stat_check.py
num = 0
with open("/proc/stat") as f:
while num < 1000 :
data = f.read()
f.seek(0, 0)
num = num + 1
==
perf shows
20.39% stat_check.py [kernel.kallsyms] [k] format_decode
13.41% stat_check.py [kernel.kallsyms] [k] number
12.61% stat_check.py [kernel.kallsyms] [k] vsnprintf
10.85% stat_check.py [kernel.kallsyms] [k] memcpy
4.85% stat_check.py [kernel.kallsyms] [k] radix_tree_lookup
4.43% stat_check.py [kernel.kallsyms] [k] seq_printf
This patch removes most of calls to vsnprintf() by adding num_to_str()
and seq_print_decimal_ull(), which prints decimal numbers without rich
functions provided by printf().
On my 8cpu box.
== Before patch ==
[root@bluextal test]# time ./stat_check.py
real 0m0.150s
user 0m0.026s
sys 0m0.121s
== After patch ==
[root@bluextal test]# time ./stat_check.py
real 0m0.055s
user 0m0.022s
sys 0m0.030s
[akpm@linux-foundation.org: remove incorrect comment, use less statck in num_to_str(), move comment from .h to .c, simplify seq_put_decimal_ull()]
[andrea@betterlinux.com: avoid breaking the ABI in /proc/stat]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrea Righi <andrea@betterlinux.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Turner <pjt@google.com>
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>
Since we no longer need the VM_ALWAYSDUMP flag, let's use the freed bit
for 'VM_NODUMP' flag. The idea is is to add a new madvise() flag:
MADV_DONTDUMP, which can be set by applications to specifically request
memory regions which should not dump core.
The specific application I have in mind is qemu: we can add a flag there
that wouldn't dump all of guest memory when qemu dumps core. This flag
might also be useful for security sensitive apps that want to absolutely
make sure that parts of memory are not dumped. To clear the flag use:
MADV_DODUMP.
[akpm@linux-foundation.org: s/MADV_NODUMP/MADV_DONTDUMP/, s/MADV_CLEAR_NODUMP/MADV_DODUMP/, per Roland]
[akpm@linux-foundation.org: fix up the architectures which broke]
Signed-off-by: Jason Baron <jbaron@redhat.com>
Acked-by: Roland McGrath <roland@hack.frob.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The motivation for this patchset was that I was looking at a way for a
qemu-kvm process, to exclude the guest memory from its core dump, which
can be quite large. There are already a number of filter flags in
/proc/<pid>/coredump_filter, however, these allow one to specify 'types'
of kernel memory, not specific address ranges (which is needed in this
case).
Since there are no more vma flags available, the first patch eliminates
the need for the 'VM_ALWAYSDUMP' flag. The flag is used internally by
the kernel to mark vdso and vsyscall pages. However, it is simple
enough to check if a vma covers a vdso or vsyscall page without the need
for this flag.
The second patch then replaces the 'VM_ALWAYSDUMP' flag with a new
'VM_NODUMP' flag, which can be set by userspace using new madvise flags:
'MADV_DONTDUMP', and unset via 'MADV_DODUMP'. The core dump filters
continue to work the same as before unless 'MADV_DONTDUMP' is set on the
region.
The qemu code which implements this features is at:
http://people.redhat.com/~jbaron/qemu-dump/qemu-dump.patch
In my testing the qemu core dump shrunk from 383MB -> 13MB with this
patch.
I also believe that the 'MADV_DONTDUMP' flag might be useful for
security sensitive apps, which might want to select which areas are
dumped.
This patch:
The VM_ALWAYSDUMP flag is currently used by the coredump code to
indicate that a vma is part of a vsyscall or vdso section. However, we
can determine if a vma is in one these sections by checking it against
the gate_vma and checking for a non-NULL return value from
arch_vma_name(). Thus, freeing a valuable vma bit.
Signed-off-by: Jason Baron <jbaron@redhat.com>
Acked-by: Roland McGrath <roland@hack.frob.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Implement UMH_KILLABLE, should be used along with UMH_WAIT_EXEC/PROC.
The caller must ensure that subprocess_info->path/etc can not go away
until call_usermodehelper_freeinfo().
call_usermodehelper_exec(UMH_KILLABLE) does
wait_for_completion_killable. If it fails, it uses
xchg(&sub_info->complete, NULL) to serialize with umh_complete() which
does the same xhcg() to access sub_info->complete.
If call_usermodehelper_exec wins, it can safely return. umh_complete()
should get NULL and call call_usermodehelper_freeinfo().
Otherwise we know that umh_complete() was already called, in this case
call_usermodehelper_exec() falls back to wait_for_completion() which
should succeed "very soon".
Note: UMH_NO_WAIT == -1 but it obviously should not be used with
UMH_KILLABLE. We delay the neccessary cleanup to simplify the back
porting.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <tj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PTRACE_SEIZE code is tested and ready for production use, remove the
code which requires special bit in data argument to make PTRACE_SEIZE
work.
Strace team prepares for a new release of strace, and we would like to
ship the code which uses PTRACE_SEIZE, preferably after this change goes
into released kernel.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PTRACE_EVENT_foo and PTRACE_O_TRACEfoo used to match.
New PTRACE_EVENT_STOP is the first event which has no corresponding
PTRACE_O_TRACE option. If we will ever want to add another such option,
its PTRACE_EVENT's value will collide with PTRACE_EVENT_STOP's value.
This patch changes PTRACE_EVENT_STOP value to prevent this.
While at it, added a comment - the one atop PTRACE_EVENT block, saying
"Wait extended result codes for the above trace options", is not true
for PTRACE_EVENT_STOP.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Tejun Heo <tj@kernel.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
