Sachin Kamat [Wed, 19 Jun 2013 00:07:27 +0000 (10:07 +1000)]
drivers/rtc/rtc-ds1511.c: fix issues related to spaces and braces
Fixes the following types of issues:
WARNING: please, no spaces at the start of a line
WARNING: braces {} are not necessary for single statement blocks
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Cc: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Sachin Kamat [Wed, 19 Jun 2013 00:07:26 +0000 (10:07 +1000)]
drivers/rtc/rtc-at91rm9200.c: include <linux/uaccess.h>
Silences the following checkpatch warning:
WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Cc: Andrew Victor <linux@maxim.org.za> Cc: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Sachin Kamat [Wed, 19 Jun 2013 00:07:25 +0000 (10:07 +1000)]
drivers/rtc/interface.c: fix checkpatch errors
Fixes the following types of errors:
ERROR: "foo* bar" should be "foo *bar"
ERROR: else should follow close brace '}'
WARNING: braces {} are not necessary for single statement blocks
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Cc: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Miklos Szeredi [Wed, 19 Jun 2013 00:07:24 +0000 (10:07 +1000)]
autofs4: translate pids to the right namespace for the daemon
The PID and the TGID of the process triggering the mount are sent to the
daemon. Currently the global pid values are sent (ones valid in the
initial pid namespace) but this is wrong if the autofs daemon itself is
not running in the initial pid namespace.
So send the pid values that are valid in the namespace of the autofs daemon.
The namespace to use is taken from the oz_pgrp pid pointer, which was set
at mount time to the mounting process' pid namespace.
If the pid translation fails (the triggering process is in an unrelated
pid namespace) then the automount fails with ENOENT.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Ian Kent <raven@themaw.net> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
autofs4: allow autofs to work outside the initial PID namespace
Enable autofs4 to work in a "container". oz_pgrp is converted from pid_t
to struct pid and this is stored at mount time based on the "pgrp=" option
or if the option is missing then the current pgrp.
The "pgrp=" option is interpreted in the PID namespace of the current
process. This option is flawed in that it doesn't carry the namespace
information, so it should be deprecated. AFAICS the autofs daemon always
sends the current pgrp, which is the default anyway.
The oz_pgrp is also set from the AUTOFS_DEV_IOCTL_SETPIPEFD_CMD ioctl.
This ioctl sets oz_pgrp to the current pgrp. It is not allowed to change
the pid namespace.
oz_pgrp is used mainly to determine whether the process traversing the
autofs mount tree is the autofs daemon itself or not. This function now
compares the pid pointers instead of the pid_t values.
One other use of oz_pgrp is in autofs4_show_options. There is shows the
virtual pid number (i.e. the one that is valid inside the PID namespace
of the calling process)
For debugging printk convert oz_pgrp to the value in the initial pid
namespace.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Ian Kent <raven@themaw.net> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Mathias Krause [Wed, 19 Jun 2013 00:07:23 +0000 (10:07 +1000)]
kprobes: handle empty/invalid input to debugfs "enabled" file
When writing invalid input to 'debug/kprobes/enabled' it'll silently be
ignored. Even worse, when writing an empty string to this file, the
outcome is purely random as the switch statement will make its decision
based on the value of an uninitialized stack variable.
Fix this by handling invalid/empty input as error returning -EINVAL.
Signed-off-by: Mathias Krause <minipli@googlemail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Steven Rostedt [Wed, 19 Jun 2013 00:07:23 +0000 (10:07 +1000)]
init: remove permanent string buffer from do_one_initcall()
do_one_initcall() uses a 64 byte string buffer to save a message. This
buffer is declared static and is only used at boot up and when a module
is loaded. As 64 bytes is very small, and this function has very limited
scope, there's no reason to waste permanent memory with this string and
not just simply put it on the stack.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We observed this problem has been occurring since 2.6.30 with
fs/binfmt_elf.c: create_elf_tables()->get_random_bytes(), introduced by f06295b44c296c8f ("ELF: implement AT_RANDOM for glibc PRNG seeding").
/*
* Generate 16 random bytes for userspace PRNG seeding.
*/
get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes));
The patch introduces a wrapper around get_random_int() which has lower
overhead than calling get_random_bytes() directly.
With this patch applied:
$ cat /proc/sys/kernel/random/entropy_avail
2731
$ cat /proc/sys/kernel/random/entropy_avail
2802
$ cat /proc/sys/kernel/random/entropy_avail
2878
Analyzed by John Sobecki.
Signed-off-by: Jie Liu <jeff.liu@oracle.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Dilger <aedilger@gmail.com> Cc: Alan Cox <alan@linux.intel.com> Cc: Arnd Bergmann <arnn@arndb.de> Cc: John Sobecki <john.sobecki@oracle.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jakub Jelinek <jakub@redhat.com> Cc: Ted Ts'o <tytso@mit.edu> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Kees Cook <keescook@chromium.org> Cc: Ulrich Drepper <drepper@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Joe Perches [Wed, 19 Jun 2013 00:07:22 +0000 (10:07 +1000)]
checkpatch: ignore SI unit CamelCase variants like "_uV"
Many existing variable names use SI like variants that should be otherwise
obvious and acceptable.
Whitelist them from the CamelCase message.
Signed-off-by: Joe Perches <joe@perches.com> Suggested-by: Phil Carmody <phil.carmody@partner.samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Joe Perches [Wed, 19 Jun 2013 00:07:21 +0000 (10:07 +1000)]
checkpatch: create an EXPERIMENTAL --fix option to correct patches
Some patches have simple defects in whitespace and formatting that
checkpatch could correct automatically. Attempt to do so.
Add a --fix option to create a "<inputfile>.EXPERIMENTAL-checkpatch-fixes"
file that tries to use normal kernel style for some of these formatting
errors.
Add warnings against using this file without verifying the changes.
Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Joe Perches [Wed, 19 Jun 2013 00:07:18 +0000 (10:07 +1000)]
checkpatch: warn when using gcc's binary constant ("0b") extension
The gcc extension for binary constants that start with 0b is only
supported with gcc version 4.3 or higher.
The kernel can still be compiled with earlier versions of gcc, so have
checkpatch emit a warning for these constants.
Restructure checkpatch's constant finding code a bit to support finding
these binary constants.
Signed-off-by: Joe Perches <joe@perches.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Dave Jones [Wed, 19 Jun 2013 00:07:17 +0000 (10:07 +1000)]
list: remove __list_for_each()
__list_for_each used to be the non prefetch() aware list walking
primitive. When we removed the prefetch macros from the list routines, it
became redundant. Given it does exactly the same thing as list_for_each
now, we might as well remove it and call list_for_each directly.
Signed-off-by: Dave Jones <davej@redhat.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: Clemens Ladisch <clemens@ladisch.de> Cc: Dave Airlie <airlied@linux.ie> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Jennifer Naumann <Jennifer.Naumann@informatik.stud.uni-erlangen.de> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Sebastian Hahn <snsehahn@cip.cs.fau.de> Cc: Stanislav Yakovlev <stas.yakovlev@gmail.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: YAMANE Toshiaki <yamanetoshi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Dave Jones [Wed, 19 Jun 2013 00:07:16 +0000 (10:07 +1000)]
sctp: convert __list_for_each use to list_for_each
Signed-off-by: Dave Jones <davej@redhat.com> Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Dave Jones [Wed, 19 Jun 2013 00:07:15 +0000 (10:07 +1000)]
ipw2200: convert __list_for_each usage to list_for_each
Signed-off-by: Dave Jones <davej@redhat.com> Cc: Stanislav Yakovlev <stas.yakovlev@gmail.com> Cc: "John W. Linville" <linville@tuxdriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jingoo Han [Wed, 19 Jun 2013 00:07:14 +0000 (10:07 +1000)]
backlight: add CONFIG_PM_SLEEP to suspend/resume functions
Add CONFIG_PM_SLEEP to suspend/resume functions to fix the following build
warning when CONFIG_PM_SLEEP is not selected. This is because sleep PM
callbacks defined by SIMPLE_DEV_PM_OPS are only used when the
CONFIG_PM_SLEEP is enabled.
drivers/video/backlight/backlight.c:211:12: warning: 'backlight_suspend' defined but not used [-Wunused-function]
drivers/video/backlight/backlight.c:225:12: warning: 'backlight_resume' defined but not used [-Wunused-function]
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Shuah Khan <shuahkhan@gmail.com> Cc: Jingoo Han <jg1.han@samsung.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Shuah Khan [Wed, 19 Jun 2013 00:07:14 +0000 (10:07 +1000)]
backlight: convert from legacy pm ops to dev_pm_ops
Convert drivers/video/backlight/class to use dev_pm_ops for power
management and remove Legacy PM ops hooks. With this change, backlight
class registers suspend/resume callbacks via class->pm (dev_pm_ops)
instead of Legacy class->suspend/resume. When __device_suspend() runs
call-backs, it will find class->pm ops for the backlight class.
Signed-off-by: Shuah Khan <shuah.kh@samsung.com> Cc: Shuah Khan <shuahkhan@gmail.com> Cc: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d06310 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jean Delvare [Wed, 19 Jun 2013 00:07:11 +0000 (10:07 +1000)]
MAINTAINERS: fix tape driver file mappings
The masks for the st and osst tape drivers in MAINTAINERS are too
broad and include unrelated files. Make the file list accurate so that
maintainers of these drivers aren't bothered with unrelated work.
Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Willem Riede <osst@riede.org> Cc: Kai Mäkisara <Kai.Makisara@kolumbus.fi> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Chuansheng Liu [Wed, 19 Jun 2013 00:07:10 +0000 (10:07 +1000)]
smp: Give WARN()ing when calling smp_call_function_many()/single() in serving irq
Currently the functions smp_call_function_many()/single() will give a
WARN()ing only in the case of irqs_disabled(), but that check is not
enough to guarantee execution of the SMP cross-calls.
In many other cases such as softirq handling/interrupt handling, the two
APIs still can not be called, just as the smp_call_function_many()
comments say:
* You must not call this function with disabled interrupts or from a
* hardware interrupt handler or from a bottom half handler. Preemption
* must be disabled when calling this function.
There is a real case for softirq DEADLOCK case:
CPUA CPUB
spin_lock(&spinlock)
Any irq coming, call the irq handler
irq_exit()
spin_lock_irq(&spinlock)
<== Blocking here due to
CPUB hold it
__do_softirq()
run_timer_softirq()
timer_cb()
call smp_call_function_many()
send IPI interrupt to CPUA
wait_csd()
Then both CPUA and CPUB will be deadlocked here.
So we should give a warning in the nmi, hardirq or softirq context as well.
Moreover, adding one new macro in_serving_irq() which indicates we are
processing nmi, hardirq or sofirq.
Signed-off-by: liu chuansheng <chuansheng.liu@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Tested-by: Fengguang Wu <fengguang.wu@intel.com> Cc: Lai Jiangshan <eag0628@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[jani.nikula@intel.com: use DMI_EXACT_MATCH for board name.] Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reported-by: <annndddrr@gmail.com> Cc: Cornel Panceac <cpanceac@gmail.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jani Nikula [Wed, 19 Jun 2013 00:07:10 +0000 (10:07 +1000)]
dmi: add support for exact DMI matches in addition to substring matching
dmi_match() considers a substring match to be a successful match. This is
not always sufficient to distinguish between DMI data for different
systems. Add support for exact string matching using strcmp() in addition
to the substring matching using strstr().
The specific use case in the i915 driver is to allow us to use an exact
match for D510MO, without also incorrectly matching D510MOV:
Oleg Nesterov [Wed, 19 Jun 2013 00:07:09 +0000 (10:07 +1000)]
kernel/sys.c:do_sysinfo(): use get_monotonic_boottime()
Change do_sysinfo() to use get_monotonic_boottime() instead of
do_posix_clock_monotonic_gettime() + monotonic_to_bootbased().
Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Tomas Janousek <tjanouse@redhat.com> Cc: Tomas Smetana <tsmetana@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
- fix comment indenting
- avoid inclusion of <asm/> files - use <linux/> where possible
- fix uniprocessor build (__dump_stack undefined)
- remove unneeded ifdef around smp.h inclusion
Cc: Alex Thorlton <athorlton@sgi.com> Cc: David S. Miller <davem@davemloft.net> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Robin Holt <holt@sgi.com> Cc: Russ Anderson <rja@sgi.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: athorlton@sgi.com Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Alex Thorlton [Wed, 19 Jun 2013 00:07:08 +0000 (10:07 +1000)]
dump_stack: serialize the output from dump_stack()
tAdd adds functionality to serialize the output from dump_stack() to avoid
mangling of the output when dump_stack is called simultaneously from
multiple cpus.
Signed-off-by: Alex Thorlton <athorlton@sgi.com> Reported-by: Russ Anderson <rja@sgi.com> Reviewed-by: Robin Holt <holt@sgi.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: David S. Miller <davem@davemloft.net> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Kees Cook [Wed, 19 Jun 2013 00:07:07 +0000 (10:07 +1000)]
drivers: avoid parsing names as kthread_run() format strings
Calling kthread_run with a single name parameter causes it to be handled
as a format string. Many callers are passing potentially dynamic string
content, so use "%s" in those cases to avoid any potential accidents.
Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Kees Cook [Wed, 19 Jun 2013 00:07:07 +0000 (10:07 +1000)]
drivers: avoid format strings in names passed to alloc_workqueue()
For the workqueue creation interfaces that do not expect format strings,
make sure they cannot accidently be parsed that way. Additionally, clean
up calls made with a single parameter that would be handled as a format
string. Many callers are passing potentially dynamic string content, so
use "%s" in those cases to avoid any potential accidents.
Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Kees Cook [Wed, 19 Jun 2013 00:07:07 +0000 (10:07 +1000)]
drivers: avoid format string in dev_set_name
Calling dev_set_name with a single paramter causes it to be handled as a
format string. Many callers are passing potentially dynamic string
content, so use "%s" in those cases to avoid any potential accidents,
including wrappers like device_create*() and bdi_register().
Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Kees Cook [Wed, 19 Jun 2013 00:07:06 +0000 (10:07 +1000)]
clean up scary strncpy(dst, src, strlen(src)) uses
Fix various weird constructions of strncpy(dst, src, strlen(src)). Length
limits should be about the space available in the destination, not
repurposed as a method to either always include or always exclude a
trailing NULL byte. Either the NULL should always be copied (using
strlcpy), or it should not be copied (using something like memcpy).
Readable code should not depend on the weird behavior of strncpy when it
hits the length limit. Better to avoid the anti-pattern entirely.
Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [staging] Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [acpi] Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ursula Braun <ursula.braun@de.ibm.com> Cc: Frank Blaschka <blaschka@linux.vnet.ibm.com> Cc: Richard Weinberger <richard@nod.at> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Dan Carpenter [Wed, 19 Jun 2013 00:07:06 +0000 (10:07 +1000)]
err.h: IS_ERR() can accept __user pointers
Sparse generates a false positive when you pass a __user or __iomem
pointer to the IS_ERR() functions.
drivers/rtc/rtc-ds1286.c:344:36: sparse: incorrect type in argument 1 (different address spaces)
drivers/rtc/rtc-ds1286.c:344:36: expected void const *ptr
drivers/rtc/rtc-ds1286.c:344:36: got unsigned int [noderef] [usertype] <asn:2>*rtcregs
We can silence these by adding a __force here and upgrading to Sparse
v0.4.5-rc1 or later.
This change has no effect when using current Sparse releases.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Christopher Li <sparse@chrisli.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Xi Wang [Wed, 19 Jun 2013 00:07:04 +0000 (10:07 +1000)]
mm/dmapool.c: fix null dev in dma_pool_create()
A few drivers invoke dma_pool_create() with a null dev. Note that dev is
dereferenced in dev_to_node(dev), causing a null pointer dereference.
A long term solution is to disallow null dev. Once the drivers are fixed,
we can simplify the core code here. For now we add WARN_ON(!dev) to
notify the driver maintainers and avoid the null pointer dereference.
Signed-off-by: Xi Wang <xi.wang@gmail.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Xi Wang [Wed, 19 Jun 2013 00:07:04 +0000 (10:07 +1000)]
drivers/usb/gadget/amd5536udc.c: avoid calling dma_pool_create() with NULL dev
Calling dma_pool_create() with dev==NULL will oops on a NUMA machine.
Rather than changing dma_pool_create() we wish to disallow passing
dev==NULL. This requires fixing up the small number of drivers which are
passing in dev==NULL.
Use &dev->pdev->dev instead of NULL.
Signed-off-by: Xi Wang <xi.wang@gmail.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Michal Hocko [Wed, 19 Jun 2013 00:07:04 +0000 (10:07 +1000)]
drop_caches: add some documentation and info message
I would like to resurrect Dave's patch. The last time it was posted was
here https://lkml.org/lkml/2010/9/16/250 and there didn't seem to be any
strong opposition.
Kosaki was worried about possible excessive logging when somebody drops
caches too often (but then he claimed he didn't have a strong opinion on
that) but I would say opposite. If somebody does that then I would really
like to know that from the log when supporting a system because it almost
for sure means that there is something fishy going on. It is also worth
mentioning that only root can write drop caches so this is not an flooding
attack vector.
I am bringing that up again because this can be really helpful when
chasing strange performance issues which (surprise surprise) turn out to
be related to artificially dropped caches done because the admin thinks
this would help...
I have just refreshed the original patch on top of the current mm tree
but I could live with KERN_INFO as well if people think that KERN_NOTICE
is too hysterical.
: From: Dave Hansen <dave@linux.vnet.ibm.com>
: Date: Fri, 12 Oct 2012 14:30:54 +0200
:
: There is plenty of anecdotal evidence and a load of blog posts
: suggesting that using "drop_caches" periodically keeps your system
: running in "tip top shape". Perhaps adding some kernel
: documentation will increase the amount of accurate data on its use.
:
: If we are not shrinking caches effectively, then we have real bugs.
: Using drop_caches will simply mask the bugs and make them harder
: to find, but certainly does not fix them, nor is it an appropriate
: "workaround" to limit the size of the caches.
:
: It's a great debugging tool, and is really handy for doing things
: like repeatable benchmark runs. So, add a bit more documentation
: about it, and add a little KERN_NOTICE. It should help developers
: who are chasing down reclaim-related bugs.
[mhocko@suse.cz: refreshed to current -mm tree]
[akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Mike Yoknis [Wed, 19 Jun 2013 00:07:03 +0000 (10:07 +1000)]
mm: memmap_init_zone() performance improvement
We have what we call an "architectural simulator". It is a computer
program that pretends that it is a computer system. We use it to test the
firmware before real hardware is available. We have booted Linux on our
simulator. As you would expect it takes longer to boot on the simulator
than it does on real hardware.
With my patch - boot time 41 minutes
Without patch - boot time 94 minutes
These numbers do not scale linearly to real hardware. But indicate to me
a place where Linux can be improved.
memmap_init_zone() loops through every Page Frame Number (pfn), including
pfn values that are within the gaps between existing memory sections. The
unneeded looping will become a boot performance issue when machines
configure larger memory ranges that will contain larger and more numerous
gaps.
The code will skip across invalid pfn values to reduce the number of loops
executed.
Signed-off-by: Mike Yoknis <mike.yoknis@hp.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Zhang Yanfei [Wed, 19 Jun 2013 00:07:03 +0000 (10:07 +1000)]
mm/sparse.c: put clear_hwpoisoned_pages within CONFIG_MEMORY_HOTREMOVE
With CONFIG_MEMORY_HOTREMOVE unset, there is a compile warning:
mm/sparse.c:755: warning: `clear_hwpoisoned_pages' defined but not used
And Bisecting it ended up pointing to 4edd7ceff ("mm, hotplug: avoid
compiling memory hotremove functions when disabled").
This is because the commit above put sparse_remove_one_section() within
the protection of CONFIG_MEMORY_HOTREMOVE but the only user of
clear_hwpoisoned_pages() is sparse_remove_one_section(), and it is not
within the protection of CONFIG_MEMORY_HOTREMOVE.
So put clear_hwpoisoned_pages within CONFIG_MEMORY_HOTREMOVE should fix
the warning.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Oleg Nesterov [Wed, 19 Jun 2013 00:07:02 +0000 (10:07 +1000)]
vfree: don't schedule free_work() if llist_add() returns false
vfree() only needs schedule_work(&p->wq) if p->list was empty, otherwise
vfree_deferred->wq is already pending or it is running and didn't do
llist_del_all() yet.
Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Zhang Yanfei [Wed, 19 Jun 2013 00:07:02 +0000 (10:07 +1000)]
mm/page_alloc.c: remove unlikely() from the current_order test
In __rmqueue_fallback(), current_order loops down from MAX_ORDER - 1 to
the order passed. MAX_ORDER is typically 11 and pageblock_order is
typically 9 on x86. Integer division truncates, so pageblock_order / 2 is
4. For the first eight iterations, it's guaranteed that current_order >=
pageblock_order / 2 if it even gets that far!
So just remove the unlikely(), it's completely bogus.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Suggested-by: David Rientjes <rientjes@google.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Zhang Yanfei [Wed, 19 Jun 2013 00:07:01 +0000 (10:07 +1000)]
mm/page_alloc.c: remove zone_type argument of build_zonelists_node
The callers of build_zonelists_node always pass MAX_NR_ZONES -1 as the
zone_type argument, so we can directly use the value in
build_zonelists_node and remove zone_type argument.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Seth Jennings [Wed, 19 Jun 2013 00:07:00 +0000 (10:07 +1000)]
zswap: add to mm/
zswap is a thin backend for frontswap that takes pages that are in the
process of being swapped out and attempts to compress them and store them
in a RAM-based memory pool. This can result in a significant I/O
reduction on the swap device and, in the case where decompressing from RAM
is faster than reading from the swap device, can also improve workload
performance.
It also has support for evicting swap pages that are currently compressed
in zswap to the swap device on an LRU(ish) basis. This functionality
makes zswap a true cache in that, once the cache is full, the oldest pages
can be moved out of zswap to the swap device so newer pages can be
compressed and stored in zswap.
This patch adds the zswap driver to mm/
Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Robert Jennings <rcj@linux.vnet.ibm.com> Cc: Jenifer Hopper <jhopper@us.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <jweiner@redhat.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Hansen <dave@sr71.net> Cc: Joe Perches <joe@perches.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Cody P Schafer <cody@linux.vnet.ibm.com> Cc: Hugh Dickens <hughd@google.com> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Seth Jennings [Wed, 19 Jun 2013 00:07:00 +0000 (10:07 +1000)]
zswap: init under_reclaim
Bob Liu reported a memory leak in zswap. This was due to the
under_reclaim field in the zbud header not being initialized
to 0, which resulted in zbud_free() not freeing the page
under the false assumption that the page was undergoing
zbud reclaim.
This patch properly initializes the under_reclaim field.
Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Reported-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Seth Jennings [Wed, 19 Jun 2013 00:07:00 +0000 (10:07 +1000)]
zbud: add to mm/
zbud is an special purpose allocator for storing compressed pages. It is
designed to store up to two compressed pages per physical page. While
this design limits storage density, it has simple and deterministic
reclaim properties that make it preferable to a higher density approach
when reclaim will be used.
zbud works by storing compressed pages, or "zpages", together in pairs in
a single memory page called a "zbud page". The first buddy is "left
justifed" at the beginning of the zbud page, and the last buddy is "right
justified" at the end of the zbud page. The benefit is that if either
buddy is freed, the freed buddy space, coalesced with whatever slack space
that existed between the buddies, results in the largest possible free
region within the zbud page.
zbud also provides an attractive lower bound on density. The ratio of
zpages to zbud pages can not be less than 1. This ensures that zbud can
never "do harm" by using more pages to store zpages than the uncompressed
zpages would have used on their own.
This implementation is a rewrite of the zbud allocator internally used by
zcache in the driver/staging tree. The rewrite was necessary to remove
some of the zcache specific elements that were ingrained throughout and
provide a generic allocation interface that can later be used by zsmalloc
and others.
This patch adds zbud to mm/ for later use by zswap.
Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Robert Jennings <rcj@linux.vnet.ibm.com> Cc: Jenifer Hopper <jhopper@us.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <jweiner@redhat.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Hansen <dave@sr71.net> Cc: Joe Perches <joe@perches.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Cody P Schafer <cody@linux.vnet.ibm.com> Cc: Hugh Dickens <hughd@google.com> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Wed, 19 Jun 2013 00:06:59 +0000 (10:06 +1000)]
memcg: do not account memory used for cache creation
The memory we used to hold the memcg arrays is currently accounted to the
current memcg. But that creates a problem, because that memory can only
be freed after the last user is gone. Our only way to know which is the
last user, is to hook up to freeing time, but the fact that we still have
some in flight kmallocs will prevent freeing to happen. I believe
therefore to be just easier to account this memory as global overhead.
Signed-off-by: Glauber Costa <glommer@openvz.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Wed, 19 Jun 2013 00:06:59 +0000 (10:06 +1000)]
memcg: also test for skip accounting at the page allocation level
The memory we used to hold the memcg arrays is currently accounted to the
current memcg. But that creates a problem, because that memory can only
be freed after the last user is gone. Our only way to know which is the
last user, is to hook up to freeing time, but the fact that we still have
some in flight kmallocs will prevent freeing to happen. I believe
therefore to be just easier to account this memory as global overhead.
This patch (of 2):
Disabling accounting is only relevant for some specific memcg internal
allocations. Therefore we would initially not have such check at
memcg_kmem_newpage_charge, since direct calls to the page allocator that
are marked with GFP_KMEMCG only happen outside memcg core. We are mostly
concerned with cache allocations and by having this test at
memcg_kmem_get_cache we are already able to relay the allocation to the
root cache and bypass the memcg caches altogether.
There is one exception, though: the SLUB allocator does not create large
order caches, but rather service large kmallocs directly from the page
allocator. Therefore, the following sequence, when backed by the SLUB
allocator:
would effectively ignore the fact that we should skip accounting, since it
will drive us directly to this function without passing through the cache
selector memcg_kmem_get_cache. Such large allocations are extremely rare
but can happen, for instance, for the cache arrays.
This was never a problem in practice, because we weren't skipping
accounting for the cache arrays. All the allocations we were skipping
were fairly small. However, the fact that we were not skipping those
allocations are a problem and can prevent the memcgs from going away. As
we fix that, we need to make sure that the fix will also work with the
SLUB allocator.
Signed-off-by: Glauber Costa <glommer@openvz.org> Reported-by: Michal Hocko <mhocko@suze.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Zhang Yanfei [Wed, 19 Jun 2013 00:06:58 +0000 (10:06 +1000)]
mm/vmalloc.c: check VM_UNINITIALIZED flag in s_show instead of show_numa_info
We should check the VM_UNITIALIZED flag in s_show(). If this flag is set,
that said, the vm_struct is not fully initialized. So it is unnecessary
to try to show the information contained in vm_struct.
We checked this flag in show_numa_info(), but I think it's better
to check it earlier.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Zhang Yanfei [Wed, 19 Jun 2013 00:06:58 +0000 (10:06 +1000)]
mm/vmalloc.c: rename VM_UNLIST to VM_UNINITIALIZED
VM_UNLIST was used to indicate that the vm_struct is not listed in vmlist.
But after commit 4341fa4 ("mm, vmalloc: remove list management of vmlist
after initializing vmalloc"), the meaning of this flag changed. It now
means the vm_struct is not fully initialized. So renaming it to
VM_UNINITIALIZED seems more reasonable.
Also change clear_vm_unlist to clear_vm_uninitialized_flag.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Zhang Yanfei [Wed, 19 Jun 2013 00:06:57 +0000 (10:06 +1000)]
mm/vmalloc.c: remove alloc_map from vmap_block
As we have removed the dead code in the vb_alloc, it seems there is no
place to use the alloc_map. So there is no reason to maintain the
alloc_map in vmap_block.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Zhang Yanfei [Wed, 19 Jun 2013 00:06:57 +0000 (10:06 +1000)]
mm/vmalloc.c: remove dead code in vb_alloc
Space in a vmap block that was once allocated is considered dirty and
not made available for allocation again before the whole block is
recycled. The result is that free space within a vmap block is always
contiguous.
So if a vmap block has enough free space for allocation, the allocation
is impossible to fail. Thus, the fragmented block purging was never invoked
from vb_alloc(). So remove this dead code.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
projects / karo-tx-linux.git / log