This does the following:
1: Splits the arguments of a function call to stop it
from exceeding 80 characters
2: Re-indents the arguments of another function call
to prevent the splitting of a quoted string.
Maintain an index of directory inodes by starting cluster, so that
fat_get_parent() can return the proper cached inode rather than inventing
one that cannot be traced back to the filesystem root.
Add a new msdos/vfat binary mount option "nfs" so that FAT filesystems
that are _not_ exported via NFS are not saddled with maintenance of an
index they will never use.
Finally, simplify NFS file handle generation and lookups. An
ext2-congruent implementation is adequate for FAT needs.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com> Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Under memory pressure, the system may evict dentries from cache. When the
FAT driver receives a NFS request involving an evicted dentry, it is
unable to reconnect it to the filesystem root. This causes the request to
fail, often with ENOENT.
This is partially due to ineffectiveness of the current FAT NFS
implementation, and partially due to an unimplemented fh_to_parent method.
The latter can cause file accesses to fail on shares exported with
subtree_check.
This patch set provides the FAT driver with the ability to
reconnect dentries. NFS file handle generation and lookups are simplified
and made congruent with ext2.
Testing has involved a memory-starved virtual machine running 3.5-rc5 that
exports a ~2 GB vfat filesystem containing a kernel tree (~770 MB, ~40000
files, 9 levels). Both 'cp -r' and 'ls -lR' operations were performed
from a client, some overlapping, some consecutive. Exports with
'subtree_check' and 'no_subtree_check' have been tested.
Note that while this patch set improves FAT's NFS support, it does not
eliminate ESTALE errors completely.
The following should be considered for NFS clients who are sensitive to ESTALE:
* Mounting with lookupcache=none
Unfortunately this can degrade performance severely, particularly for deep
filesystems.
* Incorporating VFS patches to retry ESTALE failures on the client-side,
such as https://lkml.org/lkml/2012/6/29/381
* Handling ESTALE errors in client application code
This patch:
Move NFS-related code into its own C file. No functional changes.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com> Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Fries <David@Fries.net> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
David Fries [Thu, 13 Sep 2012 01:01:21 +0000 (11:01 +1000)]
rtc_sysfs_show_hctosys(): display 0 if resume failed
Without this patch /sys/class/rtc/$CONFIG_RTC_HCTOSYS_DEVICE/hctosys
contains a 1 (meaning "This rtc was used to initialize the system
clock") even if setting the time by do_settimeofday() at bootup failed.
The RTC can also be used to set the clock on resume, if it did 1,
otherwise 0. Previously there was no indication if the RTC was used
to set the clock in resume.
This uses only CONFIG_RTC_HCTOSYS_DEVICE for conditional compilation
instead of it and CONFIG_RTC_HCTOSYS to be more consistent.
rtc_hctosys_ret was moved to class.c so class.c no longer depends on
hctosys.c.
Signed-off-by: David Fries <David@Fries.net> Cc: Matthew Garrett <mjg@redhat.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Julia Lawall [Thu, 13 Sep 2012 01:01:20 +0000 (11:01 +1000)]
drivers/rtc/rtc-coh901331.c: use clk_prepare_enable() and clk_disable_unprepare()
clk_prepare_enable and clk_disable_unprepare combine clk_prepare and
clk_enable, and clk_disable and clk_unprepare. They make the code more
concise, and ensure that clk_unprepare is called when clk_enable fails.
A simplified version of the semantic patch that introduces calls to these
functions is as follows: (http://coccinelle.lip6.fr/)
Add an RTC driver for the RTC device on Ricoh MFD Rc5t583. Ricoh RTC has
3 types of alarms. The current patch adds support for the Y-Alarm of
RC5t583 RTC.
Signed-off-by: Venu Byravarasu <vbyravarasu@nvidia.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There are several comparisons of a unsigned int to less than zero int
spear RTC driver. Such a check will always be true. In all these cases a
signed int is assigned to the unsigned variable, which is checked, before.
So the right fix is to make the checked variable signed as well. In one
case the check can be dropped completely, because all it does it returns
'err' if 'err' is less than zero, otherwise it returns 0. Since in this
particular case 'err' is always either 0 or less this is the same as just
returning 'err'.
The issue has been found using the following coccinelle semantic patch:
//<smpl>
@@
type T;
unsigned T i;
@@
(
*i < 0
|
*i >= 0
)
//</smpl>
The irq field of the jz4740_irc struct is unsigned. Yet we assign the
result of platform_get_irq() to it. platform_get_irq() may return a
negative error code and the code checks for this condition by checking if
'irq' is less than zero. But since 'irq' is unsigned this test will
always be false. Fix it by making 'irq' signed.
The issue was found using the following coccinelle semantic patch:
//<smpl>
@@
type T;
unsigned T i;
@@
(
*i < 0
|
*i >= 0
)
//</smpl>
Stephen Warren [Thu, 13 Sep 2012 01:01:18 +0000 (11:01 +1000)]
rtc: add MAX8907 RTC driver
The MAX8907 is an I2C-based power-management IC containing voltage
regulators, a reset controller, a real-time clock, and a touch-screen
controller.
The driver is based on an original by or fixed by:
* Tom Cherry
* Prashant Gaikwad
* Joseph Yoon
During upstreaming, I (swarren):
* Converted to regmap.
* Fixed handling of RTC_HOUR register containing 12.
* Fixed handling of RTC_WEEKDAY register.
* General cleanup.
Signed-off-by: Stephen Warren <swarren@nvidia.com> Cc: Tom Cherry <tcherry@nvidia.com> Cc: Prashant Gaikwad <pgaikwad@nvidia.com> Cc: Joseph Yoon <tyoon@nvidia.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
rtc: tps65910: add RTC driver for TPS65910 PMIC RTC
TPS65910 PMIC is a MFD with RTC as one of the device. Adding RTC driver
for supporting RTC device present inside TPS65910 PMIC.
Only support for RTC alarm is implemented as part of this patch.
Signed-off-by: Venu Byravarasu <vbyravarasu@nvidia.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Samuel Ortiz <sameo@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Vincent Palatin [Thu, 13 Sep 2012 01:01:17 +0000 (11:01 +1000)]
rtc: recycle id when unloading a rtc driver
When calling rtc_device_unregister, we are not freeing the id used by the
driver. So when doing a unload/load cycle for a RTC driver (e.g. rmmod
rtc_cmos && modprobe rtc_cmos), its id is incremented by one. As a
consequence, we no longer have neither an rtc0 driver nor a
/proc/driver/rtc (as it only exists for the first driver).
Signed-off-by: Vincent Palatin <vpalatin@chromium.org> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
rtc: snvs: change timeout to use a fixed number of loop
Andrew Morton <akpm@linux-foundation.org> wrote:
> The timeout code here is fragile. If acquiring the spinlock takes more
> than a millisecond or if this thread gets interrupted or preempted then
> we could easily execute that loop just a single time, and fail.
>
> It would be better to retry a fixed number of times, say 1000? That
> would take around 1 millisecond, but might be overkill.
Take Andrew's suggestion to change the timeout code to retry 1000
times.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Kim Phillips <kim.phillips@freescale.com> Cc: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Kim, Milo [Thu, 13 Sep 2012 01:01:16 +0000 (11:01 +1000)]
rtc-proc: permit the /proc/driver/rtc device to use other devices
To get time information via /proc/driver/rtc, only the first device (rtc0)
is used. If the rtcN (eg. rtc1 or rtc2) is used for the system clock,
there is no way to get information of rtcN via /proc/driver/rtc. With
this patch, the time data can be retrieved from the system clock RTC.
If the RTC_HCTOSYS_DEVICE is not defined, then rtc0 is used by default.
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Ben Gardner [Thu, 13 Sep 2012 01:01:15 +0000 (11:01 +1000)]
drivers/rtc/rtc-isl1208.c: add support for the ISL1218
The ISL1218 chip is identical to the ISL1208, except that it has 6
additional user-storage registers. This patch does not enable access to
those additional registers, but only adds the chip name to the list.
Signed-off-by: Ben Gardner <gardner.ben@gmail.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Paton J. Lewis [Thu, 13 Sep 2012 01:01:15 +0000 (11:01 +1000)]
epoll: support for disabling items, and a self-test app
Enhanced epoll_ctl to support EPOLL_CTL_DISABLE, which disables an epoll
item. If epoll_ctl doesn't return -EBUSY in this case, it is then safe to
delete the epoll item in a multi-threaded environment. Also added a new
test_epoll self- test app to both demonstrate the need for this feature
and test it.
Signed-off-by: Paton J. Lewis <palewis@adobe.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Jason Baron <jbaron@redhat.com> Cc: Paul Holland <pholland@adobe.com> Cc: Davide Libenzi <davidel@xmailserver.org> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Joe Perches [Thu, 13 Sep 2012 01:01:15 +0000 (11:01 +1000)]
CodingStyle: add networking specific block comment style
The block comment style in net/ and drivers/net is non-standard.
Document it.
Signed-off-by: Joe Perches <joe@perches.com> Cc: "Allan, Bruce W" <bruce.w.allan@intel.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Joe Perches [Thu, 13 Sep 2012 01:01:15 +0000 (11:01 +1000)]
checkpatch: check networking specific block comment style
In an effort to get fewer checkpatch reviewer corrections, add a
networking specific style test for the preferred networking comment style.
/* The preferred style for block comments in
* drivers/net/... and net/... is like this
*/
These tests are only used in net/ and drivers/net/
Tested with:
$ cat drivers/net/t.c
/* foo */
/*
* foo
*/
/* foo
*/
/* foo
* bar */
$ ./scripts/checkpatch.pl -f drivers/net/t.c
WARNING: networking block comments don't use an empty /* line, use /* Comment...
#4: FILE: net/t.c:4:
+
+/*
WARNING: networking block comments put the trailing */ on a separate line
#12: FILE: net/t.c:12:
+ * bar */
total: 0 errors, 2 warnings, 12 lines checked
Signed-off-by: Joe Perches <joe@perches.com> Cc: "Allan, Bruce W" <bruce.w.allan@intel.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Joe Perches [Thu, 13 Sep 2012 01:01:14 +0000 (11:01 +1000)]
checkpatch: update suggested printk conversions
Direct conversion of printk(KERN_<LEVEL>... to pr_<level> isn't the
preferred conversion when a struct net_device or struct device is
available.
Hint that using netdev_<level> or dev_<level> is preferred to using
pr_<level>. Add netdev_dbg and dev_dbg variants too.
Miscellaneous whitespace neatening of a misplaced close brace.
Signed-off-by: Joe Perches <joe@perches.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pasi Savanainen [Thu, 13 Sep 2012 01:01:14 +0000 (11:01 +1000)]
checkpatch: check utf-8 content from a commit log when it's missing from charset
Check that a commit log doesn't contain UTF-8 when a mail header
explicitly defines a different charset, like
'Content-Type: text/plain; charset="us-ascii"'
Signed-off-by: Pasi Savanainen <pasi.savanainen@nixu.com> Cc: Joe Perches <joe@perches.com> Cc: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
fs/compat_ioctl.c: In function 'serial_struct_ioctl':
fs/compat_ioctl.c:609:38: warning: typedef 'SS' locally defined but not used [-Wunused-local-typedefs]
typedef struct serial_struct SS;
Jan Beulich [Thu, 13 Sep 2012 01:01:12 +0000 (11:01 +1000)]
lib/Kconfig.debug: adjust hard-lockup related Kconfig options
The main option should not appear in the resulting .config when the
dependencies aren't met (i.e. use "depends on" rather than directly
setting the default from the combined dependency values).
The sub-options should depend on the main option rather than a more
generic higher level one.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Don Zickus <dzickus@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Alex Elder [Thu, 13 Sep 2012 01:01:11 +0000 (11:01 +1000)]
lib/parser.c: avoid overflow in match_number()
The result of converting an integer value to another signed integer type
that's unable to represent the original value is implementation defined.
(See notes in section 6.3.1.3 of the C standard.)
In match_number(), the result of simple_strtol() (which returns type long)
is assigned to a value of type int.
Instead, handle the result of simple_strtol() in a well-defined way, and
return -ERANGE if the result won't fit in the int variable used to hold
the parsed result.
No current callers pay attention to the particular error value returned,
so this additional return code shouldn't do any harm.
Signed-off-by: Alex Elder <elder@inktank.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This driver was for the ProGear webpad device which was produced in
2000/2001 and is not available on a market. I no longer have this
hardware so can not even check how Linux works on it.
Signed-off-by: Marcin Juszkiewicz <marcin@juszkiewicz.com.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This driver is a general version for LM3639 backlgiht + flash driver chip
of TI.
LM3639:
The LM3639 is a single chip LCD Display Backlight driver + white LED
Camera driver. Programming is done over an I2C compatible interface.
www.ti.com
Signed-off-by: G.Shark Jeong <gshark.jeong@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Daniel Jeong <daniel.jeong@ti.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This driver is a general version for LM3630 backlgiht driver chip of TI.
LM3630 :
The LM3630 is a current mode boost converter which supplies the power
and controls the current in two strings of up to 10 LEDs per string.
Programming is done over an I2C compatible interface.
www.ti.com
Signed-off-by: G.Shark Jeong <gshark.jeong@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Daniel Jeong <daniel.jeong@ti.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jingoo Han [Thu, 13 Sep 2012 01:01:08 +0000 (11:01 +1000)]
drivers/video/backlight/kb3886_bl.c: use usleep_range() instead of msleep() for small sleeps
Since msleep() might not sleep for the desired amount when less than 20ms,
use usleep_range().
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Claudio Nieder <private@claudio.ch> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Sachin Kamat <sachin.kamat@linaro.org> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jingoo Han [Thu, 13 Sep 2012 01:01:08 +0000 (11:01 +1000)]
drivers/video/backlight/ltv350qv.c: use usleep_range() instead of msleep() for small sleeps
Since msleep() might not sleep for the desired amount when less than 20ms,
use usleep_range().
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Sachin Kamat <sachin.kamat@linaro.org> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jingoo Han [Thu, 13 Sep 2012 01:01:08 +0000 (11:01 +1000)]
drivers/video/backlight/da9052_bl.c: use usleep_range() instead of msleep() for small sleeps
Since msleep() might not sleep for the desired amount when less than 20ms,
use usleep_range().
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Ashish Jangam <ashish.jangam@kpitcummins.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Sachin Kamat <sachin.kamat@linaro.org> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
drivers/video/backlight/pwm_bl.c: add device tree support for Low Threshold Brightness
Low Threshold Brightness should be configured to have a linear relation in
brightness scale. This patch adds device tree support for low threshold
brightness as optional one for pwm_backlight.
Signed-off-by: Philip, Avinash <avinashphilip@ti.com> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: Rob Herring <rob.herring@calxeda.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Joe Perches [Thu, 13 Sep 2012 01:01:07 +0000 (11:01 +1000)]
MAINTAINERS: Update gianfar_ptp after renaming
commit ec21e2ec36769 ("freescale: Move the Freescale drivers")
moved the files, update the pattern.
Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Richard Cochran <richardcochran@gmail.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Andy Shevchenko [Thu, 13 Sep 2012 01:01:06 +0000 (11:01 +1000)]
lib/vsprintf: update documentation to cover all of %p[Mm][FR]
Acked-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
kernel/sys.c: call disable_nonboot_cpus() in kernel_restart()
As kernel_power_off() calls disable_nonboot_cpus(), we may also want to
have kernel_restart() call disable_nonboot_cpus(). Doing so can help
machines that require boot cpu be the last alive cpu during reboot to
survive with kernel restart.
This fixes one reboot issue seen on imx6q (Cortex-A9 Quad). The machine
requires that the restart routine be run on the primary cpu rather than
secondary ones. Otherwise, the secondary core running the restart routine
will fail to come to online after reboot.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Historically, the top three bytes of personality have been used for things
such as ADDR_NO_RANDOMIZE, which made sense only for specific
architectures.
We now however have a flag there that is general no matter the
architecture (UNAME26); generally we have to be careful to preserve the
personality flags across exec().
This patch fixes tile architecture not to forcefully overwrite personality
flags during exec().
In addition to that, we fix two other things along the way:
- exec_domain switching is fixed -- set_personality() should always
be used instead of directly assigning to current->personality.
- as pointed out by Arnd Bergmann, PER_LINUX_32BIT is not used anywhere
by tile, so let's just drop that in favor of PER_LINUX
Signed-off-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
cross-arch: don't corrupt personality flags upon exec()
Historically, the top three bytes of personality have been used for things
such as ADDR_NO_RANDOMIZE, which made sense only for specific
architectures.
We now however have a flag there that is general no matter the
architecture (UNAME26); generally we have to be careful to preserve the
personality flags across exec().
This patch tries to fix all architectures that forcefully overwrite
personality flags during exec() (ppc32 and s390 have been fixed recently
by commits f9783ec86 and 59e4c3a2f in a similar way already).
Signed-off-by: Jiri Kosina <jkosina@suse.cz> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Mark Salter <msalter@redhat.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Michal Simek <monstr@monstr.eu> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chen Liqin <liqin.chen@sunplusct.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Daniel Mack [Thu, 13 Sep 2012 01:01:04 +0000 (11:01 +1000)]
lis3: lis3lv02d_spi.c: include linux/of.h
This include is needed to define of_match:ptr() for !CONFIG_OF &&
1CONFIG_DTC.
Signed-off-by: Daniel Mack <zonque@gmail.com> Reported-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Commit 6afe1a1fe8ff83f6a ("PM: Remove legacy PM") removed the
initialization of retval, causing:
arch/frv/kernel/pm.c: In function 'sysctl_pm_do_suspend':
arch/frv/kernel/pm.c:165:5: warning: 'retval' may be used uninitialized in this function [-Wuninitialized]
Remove the variable completely to fix this, and convert to a proper
switch (...) { ... } construct to improve readability.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mm: compaction: move fatal signal check out of compact_checklock_irqsave
c67fe3752 ("mm: compaction: Abort async compaction if locks are contended
or taking too long") addressed a lock contention problem in compaction by
introducing compact_checklock_irqsave() that effecively aborting async
compaction in the event of compaction.
To preserve existing behaviour it also moved a fatal_signal_pending()
check into compact_checklock_irqsave() but that is very misleading. It
"hides" the check within a locking function but has nothing to do with
locking as such. It just happens to work in a desirable fashion.
This patch moves the fatal_signal_pending() check to
isolate_migratepages_range() where it belongs. Arguably the same check
should also happen when isolating pages for freeing but it's overkill.
Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Shaohua Li <shli@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Minchan Kim [Thu, 13 Sep 2012 01:01:01 +0000 (11:01 +1000)]
memory-hotplug: don't replace lowmem pages with highmem
The changelog for 6a6dccba2 ("mm: cma: don't replace lowmem pages with
highmem") mentioned that lowmem pages can be replaced by highmem pages
during CMA migration. 6a6dccba2 fixed that issue.
Quote from that changelog:
: The filesystem layer expects pages in the block device's mapping to not
: be in highmem (the mapping's gfp mask is set in bdget()), but CMA can
: currently replace lowmem pages with highmem pages, leading to crashes in
: filesystem code such as the one below:
:
: Unable to handle kernel NULL pointer dereference at virtual address 00000400
: pgd = c0c98000
: [00000400] *pgd=00c91831, *pte=00000000, *ppte=00000000
: Internal error: Oops: 817 [#1] PREEMPT SMP ARM
: CPU: 0 Not tainted (3.5.0-rc5+ #80)
: PC is at __memzero+0x24/0x80
: ...
: Process fsstress (pid: 323, stack limit = 0xc0cbc2f0)
: Backtrace:
: [<c010e3f0>] (ext4_getblk+0x0/0x180) from [<c010e58c>] (ext4_bread+0x1c/0x98)
: [<c010e570>] (ext4_bread+0x0/0x98) from [<c0117944>] (ext4_mkdir+0x160/0x3bc)
: r4:c15337f0
: [<c01177e4>] (ext4_mkdir+0x0/0x3bc) from [<c00c29e0>] (vfs_mkdir+0x8c/0x98)
: [<c00c2954>] (vfs_mkdir+0x0/0x98) from [<c00c2a60>] (sys_mkdirat+0x74/0xac)
: r6:00000000 r5:c152eb40 r4:000001ff r3:c14b43f0
: [<c00c29ec>] (sys_mkdirat+0x0/0xac) from [<c00c2ab8>] (sys_mkdir+0x20/0x24)
: r6:beccdcf0 r5:00074000 r4:beccdbbc
: [<c00c2a98>] (sys_mkdir+0x0/0x24) from [<c000e3c0>] (ret_fast_syscall+0x0/0x30)
Memory-hotplug has same problem as CMA has so the same fix can be applied
to memory-hotplug as well.
Fix it by reusing.
Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Shaohua Li [Thu, 13 Sep 2012 01:01:00 +0000 (11:01 +1000)]
mm: compaction: check lock contention first before taking lock
isolate_migratepages_range will take zone->lru_lock first and check if the
lock is contented, if yes, it will release the lock. This isn't
efficient. If the lock is truly contented, a lock/unlock pair will
increase the lock contention. We'd better check if the lock is contended
first. compact_trylock_irqsave perfectly meets the requirement.
Signed-off-by: Shaohua Li <shli@fusionio.com> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
make compact_zone_order() require non-NULL arg `contended'
Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan@kernel.org> Cc: Shaohua Li <shli@fusionio.com> Cc: Shaohua Li <shli@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Shaohua Li [Thu, 13 Sep 2012 01:00:59 +0000 (11:00 +1000)]
mm: compaction: abort compaction loop if lock is contended or run too long
isolate_migratepages_range() might isolate no pages, for example, when
zone->lru_lock is contended and compaction is async. In this case, we
should abort compaction, otherwise, compact_zone will run a useless loop
and make zone->lru_lock is even contended.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Shaohua Li <shli@fusionio.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Wanpeng Li [Thu, 13 Sep 2012 01:00:58 +0000 (11:00 +1000)]
mm/memblock: reduce overhead in binary search
When checking that the indicated address belongs to the memory region, the
memory regions are checked one by one through a binary search, which will
be time consuming.
If the indicated address isn't in the memory region, then we needn't do
the time-consuming search. Add a check on the indicated address for that
purpose.
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Gavin Shan <shangw@linux.vnet.ibm.com> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Shaohua Li [Thu, 13 Sep 2012 00:59:00 +0000 (10:59 +1000)]
swap: add a simple detector for inappropriate swapin readahead
The swapin readahead does a blind readahead whether or not the swapin is
sequential. This is ok for harddisk because large reads have relatively
small costs and if the readahead pages are unneeded they can be reclaimed
easily. But for SSD devices large reads are more expensive than small
one. If readahead pages are unneeded, reading them in caused significant
overhead
This patch addes a simple random read detection similar to file mmap
readahead. If a random read is detected, swapin readahead will be
skipped. This improves a lot for a swap workload with random IO in a fast
SSD.
I run anonymous mmap write micro benchmark, which will triger swapin/swapout.
For both harddisk and SSD, the randwrite swap workload run time is reduced
significantly. Sequential write swap workload hasn't chanage.
Interestingly, the randwrite harddisk test is improved too. This might be
because swapin readahead needs to allocate extra memory, which further
tights memory pressure, so more swapout/swapin.
Signed-off-by: Shaohua Li <shli@fusionio.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
do the "#define foo foo" trick in the conventional manner
Cc: "David S. Miller" <davem@davemloft.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Michal Simek <monstr@monstr.eu> Cc: Rik van Riel <riel@redhat.com> Cc: Shaohua Li <shli@fusionio.com> Cc: Shaohua Li <shli@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The x86 implementation of atomic_dec_if_positive is quite generic, so make
it available to all architectures.
This is needed for "swap: add a simple detector for inappropriate swapin
readahead".
Signed-off-by: Shaohua Li <shli@fusionio.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rik van Riel <riel@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michal Simek <monstr@monstr.eu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Minchan Kim [Thu, 13 Sep 2012 00:59:00 +0000 (10:59 +1000)]
memory-hotplug: fix pages missed by race rather than failing
If race between allocation and isolation in memory-hotplug offline
happens, some pages could be in MIGRATE_MOVABLE of free_list although the
pageblock's migratetype of the page is MIGRATE_ISOLATE.
The race could be detected by get_freepage_migratetype in
__test_page_isolated_in_pageblock. If it is detected, now EBUSY gets
bubbled all the way up and the hotplug operations fails.
But better idea is instead of returning and failing memory-hotremove, move
the free page to the correct list at the time it is detected. It could
enhance memory-hotremove operation success ratio although the race is
really rare.
free_hot_cold_page(Page A)
/* without zone->lock */
migratetype = get_pageblock_migratetype(Page A);
/*
* Page could be moved into MIGRATE_MOVABLE
* of per_cpu_pages
*/
list_add_tail(&page->lru, &pcp->lists[migratetype]);
/* Page A could be in MIGRATE_MOVABLE of free_list. */
check_pages_isolated
__test_page_isolated_in_pageblock
/*
* We can't catch freed page which
* is free_list[MIGRATE_MOVABLE]
*/
if (PageBuddy(page A))
pfn += 1 << page_order(page A);
/* So, Page A could be allocated */
__offline_isolated_pages
/*
* BUG_ON hit or offline page
* which is used by someone
*/
BUG_ON(!PageBuddy(page A));
This patch checks page's migratetype in freelist in
__test_page_isolated_in_pageblock. So now
__test_page_isolated_in_pageblock can check the page caused by above race
and can fail of memory offlining.
Minchan Kim [Thu, 13 Sep 2012 00:58:59 +0000 (10:58 +1000)]
mm: remain migratetype in freed page
The page allocator caches the pageblock information in page->private while
it is in the PCP freelists but this is overwritten with the order of the
page when freed to the buddy allocator. This patch stores the migratetype
of the page in the page->index field so that it is available at all times
when the page remain in free_list.
This patch adds a new call site in __free_pages_ok so it might be overhead
a bit but it's for high order allocation. So I believe damage isn't hurt.
Minchan Kim [Thu, 13 Sep 2012 00:58:59 +0000 (10:58 +1000)]
mm: page_alloc: use get_freepage_migratetype() instead of page_private()
The page allocator uses set_page_private and page_private for handling
migratetype when it frees page. Let's replace them with [set|get]
_freepage_migratetype to make it more clear.
Haggai Eran [Thu, 13 Sep 2012 00:58:59 +0000 (10:58 +1000)]
mm: wrap calls to set_pte_at_notify with invalidate_range_start and invalidate_range_end
In order to allow sleeping during invalidate_page mmu notifier calls, we
need to avoid calling when holding the PT lock. In addition to its direct
calls, invalidate_page can also be called as a substitute for a change_pte
call, in case the notifier client hasn't implemented change_pte.
This patch drops the invalidate_page call from change_pte, and instead
wraps all calls to change_pte with invalidate_range_start and
invalidate_range_end calls.
Note that change_pte still cannot sleep after this patch, and that clients
implementing change_pte should not take action on it in case the number of
outstanding invalidate_range_start calls is larger than one, otherwise
they might miss a later invalidation.
Signed-off-by: Haggai Eran <haggaie@mellanox.com> Cc: Andrea Arcangeli <andrea@qumranet.com> Cc: Sagi Grimberg <sagig@mellanox.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Cc: Or Gerlitz <ogerlitz@mellanox.com> Cc: Haggai Eran <haggaie@mellanox.com> Cc: Shachar Raindel <raindel@mellanox.com> Cc: Liran Liss <liranl@mellanox.com> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Haggai Eran [Thu, 13 Sep 2012 00:58:58 +0000 (10:58 +1000)]
mm: Fix compiler warning in copy_page_range
This patch fixes the warning about mmun_start/end used uninitialized in
copy_page_range, by initializing them regardless of whether the notifiers are
actually called. It also makes sure the vm_flags in copy_page_range are only
read once.
Signed-off-by: Haggai Eran <haggaie@mellanox.com> Reviewed-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mm: move all mmu notifier invocations to be done outside the PT lock
In order to allow sleeping during mmu notifier calls, we need to avoid
invoking them under the page table spinlock. This patch solves the
problem by calling invalidate_page notification after releasing the lock
(but before freeing the page itself), or by wrapping the page invalidation
with calls to invalidate_range_begin and invalidate_range_end.
To prevent accidental changes to the invalidate_range_end arguments after
the call to invalidate_range_begin, the patch introduces a convention of
saving the arguments in consistently named locals:
unsigned long mmun_start; /* For mmu_notifiers */
unsigned long mmun_end; /* For mmu_notifiers */
The patch changes code to use this convention for all calls to
mmu_notifier_invalidate_range_start/end, except those where the calls are
close enough so that anyone who glances at the code can see the values
aren't changing.
This patchset is a preliminary step towards on-demand paging design to be
added to the RDMA stack.
Why do we want on-demand paging for Infiniband?
Applications register memory with an RDMA adapter using system calls,
and subsequently post IO operations that refer to the corresponding
virtual addresses directly to HW. Until now, this was achieved by
pinning the memory during the registration calls. The goal of on demand
paging is to avoid pinning the pages of registered memory regions (MRs).
This will allow users the same flexibility they get when swapping any
other part of their processes address spaces. Instead of requiring the
entire MR to fit in physical memory, we can allow the MR to be larger,
and only fit the current working set in physical memory.
Why should anyone care? What problems are users currently experiencing?
This can make programming with RDMA much simpler. Today, developers
that are working with more data than their RAM can hold need either to
deregister and reregister memory regions throughout their process's
life, or keep a single memory region and copy the data to it. On demand
paging will allow these developers to register a single MR at the
beginning of their process's life, and let the operating system manage
which pages needs to be fetched at a given time. In the future, we
might be able to provide a single memory access key for each process
that would provide the entire process's address as one large memory
region, and the developers wouldn't need to register memory regions at
all.
Is there any prospect that any other subsystems will utilise these
infrastructural changes? If so, which and how, etc?
As for other subsystems, I understand that XPMEM wanted to sleep in
MMU notifiers, as Christoph Lameter wrote at
http://lkml.indiana.edu/hypermail/linux/kernel/0802.1/0460.html and
perhaps Andrea knows about other use cases.
Scheduling in mmu notifications is required since we need to sync the
hardware with the secondary page tables change. A TLB flush of an IO
device is inherently slower than a CPU TLB flush, so our design works by
sending the invalidation request to the device, and waiting for an
interrupt before exiting the mmu notifier handler.
Avi said:
kvm may be a buyer. kvm::mmu_lock, which serializes guest page
faults, also protects long operations such as destroying large ranges.
It would be good to convert it into a spinlock, but as it is used inside
mmu notifiers, this cannot be done.
(there are alternatives, such as keeping the spinlock and using a
generation counter to do the teardown in O(1), which is what the "may"
is doing up there).
Signed-off-by: Andrea Arcangeli <andrea@qumranet.com> Signed-off-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Haggai Eran <haggaie@mellanox.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Cc: Or Gerlitz <ogerlitz@mellanox.com> Cc: Haggai Eran <haggaie@mellanox.com> Cc: Shachar Raindel <raindel@mellanox.com> Cc: Liran Liss <liranl@mellanox.com> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Minchan Kim [Thu, 13 Sep 2012 00:58:57 +0000 (10:58 +1000)]
mm: cma: discard clean pages during contiguous allocation instead of migration
Drop clean cache pages instead of migration during alloc_contig_range() to
minimise allocation latency by reducing the amount of migration that is
necessary. It's useful for CMA because latency of migration is more
important than evicting the background process's working set. In
addition, as pages are reclaimed then fewer free pages for migration
targets are required so it avoids memory reclaiming to get free pages,
which is a contributory factor to increased latency.
I measured elapsed time of __alloc_contig_migrate_range() which migrates
10M in 40M movable zone in QEMU machine.
Before - 146ms, After - 7ms
Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Mel Gorman <mgorman@suse.de> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Cc: Rik van Riel <riel@redhat.com> Tested-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
memory-hotplug: build zonelists when offlining pages
online_pages() does build_all_zonelists() and zone_pcp_update(), I think
offline_pages() should do it too.
When the zone has no memory to allocate, remove it from other nodes'
zonelists. zone_batchsize() depends on zone's present pages, if zone's
present pages are changed, zone's pcp should be updated.
During mremap(), the destination VMA is generally placed after the
original vma in rmap traversal order: in move_vma(), we always have
new_pgoff >= vma->vm_pgoff, and as a result new_vma->vm_pgoff >=
vma->vm_pgoff unless vma_merge() merged the new vma with an adjacent one.
When the destination VMA is placed after the original in rmap traversal
order, we can avoid taking the rmap locks in move_ptes().
Essentially, this reintroduces the optimization that had been disabled in
"mm anon rmap: remove anon_vma_moveto_tail". The difference is that we
don't try to impose the rmap traversal order; instead we just rely on
things being in the desired order in the common case and fall back to
taking locks in the uncommon case. Also we skip the i_mmap_mutex in
addition to the anon_vma lock: in both cases, the vmas are traversed in
increasing vm_pgoff order with ties resolved in tree insertion order.
Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
projects / karo-tx-linux.git / log