Wolfgang Muees [Fri, 5 Mar 2010 21:43:39 +0000 (13:43 -0800)]
mmc: at91_mci: fix timeout errors
Fix two timeout errors, one for slow SDHC cards and one for slow users
while inserting SD cards.
Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Andrew Victor <avictor.za@gmail.com> Cc: <linux-mmc@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wolfgang Muees [Fri, 5 Mar 2010 21:43:38 +0000 (13:43 -0800)]
mmc: at91_mci: fix pointer errors
Fixes two pointer errors, one which leads to memory overwrites if used
with large chunks of data.
Signed-off-by: Wolfgang Muees <wolfgang.mues@auerswald.de> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Andrew Victor <avictor.za@gmail.com> Cc: <linux-mmc@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
s3cmci: initialize default platform data no_wprotect and no_detect with 1
If no platform_data was givin to the device it's going to use it's default
platform data struct which has all fields initialized to zero. As a
result the driver is going to try to request gpio0 both as write protect
and card detect pin. Which of course will fail and makes the driver
unusable
Previously to the introduction of no_wprotect and no_detect the behavior
was to assume that if no platform data was given there is no write protect
or card detect pin. This patch restores that behavior.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Cc: Ben Dooks <ben-linux@fluff.org> Cc: <linux-mmc@vger.kernel.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nicolas Pitre [Fri, 5 Mar 2010 21:43:34 +0000 (13:43 -0800)]
sdio: kick the interrupt thread upon a resume
Some SDIO cards may suspend while keeping function interrupts active
especially in the powered suspend case. Upon resume we need to kick the
SDIO interrupt thread to check for pending interrupts and to restart card
IRQ detection at the host controller level.
Signed-off-by: Nicolas Pitre <nico@marvell.com> Cc: <linux-mmc@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Chris Ball [Fri, 5 Mar 2010 21:43:33 +0000 (13:43 -0800)]
sdio: don't use CMD[357] as part of a powered SDIO resume
Seen on a Marvell 8686 SDIO card and Via VX855 controller: we must avoid
sending CMD3/5/7 on a resume where power has been maintained, because the
8686 will refuse to respond to them and the MMC stack will give up on the
card.
Signed-off-by: Chris Ball <cjb@laptop.org> Signed-off-by: Nicolas Pitre <nico@marvell.com> Cc: <linux-mmc@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nicolas Pitre [Fri, 5 Mar 2010 21:43:31 +0000 (13:43 -0800)]
sdio: introduce API for special power management features
This patch series provides the core changes needed to allow SDIO cards to
remain powered and active while the host system is suspended, and let them
wake up the host system when needed. This is used to implement
wake-on-lan with SDIO wireless cards at the moment. Patches to add that
support to the libertas driver will be posted separately.
This patch:
Some SDIO cards have the ability to keep on running autonomously when the
host system is suspended, and wake it up when needed. This however
requires that the host controller preserve power to the card, and
configure itself appropriately for wake-up.
There is however 4 layers of abstractions involved: the host controller
driver, the MMC core code, the SDIO card management code, and the actual
SDIO function driver. To make things simple and manageable, host drivers
must advertise their PM capabilities with a feature bitmask, then function
drivers can query and set those features from their suspend method. Then
each layer in the suspend call chain is expected to act upon those bits
accordingly.
[akpm@linux-foundation.org: fix typo in comment] Signed-off-by: Nicolas Pitre <nico@marvell.com> Cc: <linux-mmc@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ben Dooks [Fri, 5 Mar 2010 21:43:29 +0000 (13:43 -0800)]
sdhci: improve sdhci sdhci_set_adma_desc() code
sdhci_set_adma_desc() is using byte-writes to write data in a specified
order into memory. Change to using __le16 for the two byte and __le32 for
the four byte cases and use the cpu_to_{le16,le32} to do the conversion
before writing.
This will reduce the size of the code and the number of writes as we no
longer need to chop the data up before writing.
As an example on ARM S3C64XX SoC, in little-endian configuration:
Ben Dooks [Fri, 5 Mar 2010 21:43:26 +0000 (13:43 -0800)]
sdhci: add adma descriptor set call
The code to write the ADMA descriptor into memory is repeated several
times throughout sdhci_adma_table_pre, and thus should be moved into a
common function. This will also be useful if the patch to make the write
more efficient is accepted.
Signed-off-by: Ben Dooks <ben-linux@fluff.org> Cc: Pierre Ossman <pierre@ossman.eu> Cc: <linux-mmc@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Maxim Levitsky [Fri, 5 Mar 2010 21:43:20 +0000 (13:43 -0800)]
ricoh_mmc: port from driver to pci quirk
This patch solves nasty problem original driver has.
Original goal of the ricoh_mmc was to disable this device because then,
mmc cards can be read using standard SDHCI controller, thus avoiding
writing of yet another driver.
However, the act of disablement, makes other pci functions that belong to
this controller (xD and memstick) shift up one level, thus pci core has
now wrong idea about these devices.
To fix this issue, this patch moves the driver into the pci quirk section,
thus it is executes before the pci is enumerated, and therefore solving
that issue, also same sequence of commands is performed on resume for same
reasons.
Also regardless of the above, this way is cleaner. You still need to set
CONFIG_MMC_RICOH_MMC to enable this quirk
Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com> Acked-by: Philip Langdale <philipl@overt.org> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Cc: <linux-mmc@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Fri, 5 Mar 2010 21:43:19 +0000 (13:43 -0800)]
fs/compat_ioctl.c: suppress two warnings
fs/compat_ioctl.c: In function 'do_ioctl_trans':
fs/compat_ioctl.c:534: warning: 'karg' may be used uninitialized in this function
fs/compat_ioctl.c:533: warning: 'kcmd' may be used uninitialized in this function
fs/compat_ioctl.c:656: warning: 'ret' may be used uninitialized in this function
Reduces text size by 44 bytes.
If someone calls one of these functions with an unexpected argument, the
code's buggy as-is.
Amerigo Wang <amwang@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Don Mullis [Fri, 5 Mar 2010 21:43:15 +0000 (13:43 -0800)]
lib: more scalable list_sort()
XFS and UBIFS can pass long lists to list_sort(); this alternative
implementation scales better, reaching ~3x performance gain when list
length exceeds the L2 cache size.
Stand-alone program timings were run on a Core 2 duo L1=32KB L2=4MB,
gcc-4.4, with flags extracted from an Ubuntu kernel build. Object size is
581 bytes compared to 455 for Mark J. Roberts' code.
Worst case for either implementation is a list length just over a power of
two, and to roughly the same degree, so here are timing results for a
range of 2^N+1 lengths. List elements were 16 bytes each including malloc
overhead; initial order was random.
Simon's algorithm performs O(log N) passes over the entire input list,
doing merges of sublists that double in size on each pass. The generic
algorithm instead merges pairs of equal length lists as early as possible,
in recursive order. For either algorithm, the elements that extend the
list beyond power-of-two length are a special case, handled as nearly as
possible as a "rounding-up" to a full POT.
Some intuition for the locality of reference implications of merge order
may be gotten by watching this animation:
http://www.sorting-algorithms.com/merge-sort
Simon's algorithm requires only O(1) extra space rather than the generic
algorithm's O(log N), but in my non-recursive implementation the actual
O(log N) data is merely a vector of ~20 pointers, which I've put on the
stack.
Long-running list_sort() calls: If the list passed in may be long, or the
client's cmp() callback function is slow, the client's cmp() may
periodically invoke cond_resched() to voluntarily yield the CPU. All
inner loops of list_sort() call back to cmp().
Stability of the sort: distinct elements that compare equal emerge from
the sort in the same order as with Mark's code, for simple test cases. A
boot-time test is provided to verify this and other correctness
requirements.
A kernel that uses drm.ko appears to run normally with this change; I have
no suitable hardware to similarly test the use by UBIFS.
[akpm@linux-foundation.org: style tweaks, fix comment, make list_sort_test __init] Signed-off-by: Don Mullis <don.mullis@gmail.com> Cc: Dave Airlie <airlied@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Artem Bityutskiy <dedekind@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Joe Perches <joe@perches.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
perlcritic is a standard checker for Perl Best Practices. This patch
fixes most of the warnings in the get_maintainer script. If kernel
programmers are going to have checkpatch they should write clean scripts
as well...
Bareword file handle opened at line 176, column 1. See pages 202,204 of PBP. (Severity: 5)
Two-argument "open" used at line 176, column 1. See page 207 of PBP. (Severity: 5)
Bareword file handle opened at line 207, column 5. See pages 202,204 of PBP. (Severity: 5)
Two-argument "open" used at line 207, column 5. See page 207 of PBP. (Severity: 5)
Bareword file handle opened at line 246, column 6. See pages 202,204 of PBP. (Severity: 5)
Two-argument "open" used at line 246, column 6. See page 207 of PBP. (Severity: 5)
Bareword file handle opened at line 258, column 2. See pages 202,204 of PBP. (Severity: 5)
Two-argument "open" used at line 258, column 2. See page 207 of PBP. (Severity: 5)
Expression form of "eval" at line 983, column 17. See page 161 of PBP. (Severity: 5)
Expression form of "eval" at line 985, column 17. See page 161 of PBP. (Severity: 5)
Subroutine prototypes used at line 1186, column 1. See page 194 of PBP. (Severity: 5)
Subroutine prototypes used at line 1206, column 1. See page 194 of PBP. (Severity: 5)
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Fri, 5 Mar 2010 21:43:04 +0000 (13:43 -0800)]
scripts/get_maintainer.pl: add ability to read from STDIN
Doesn't need or accept '-' as a trailing option to read stdin. Doesn't
print usage() after bad options. Adds --usage as command line equivalent
of --help
Suggested-by: Borislav Petkov <petkovbb@googlemail.com> Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add an imperfect option to search a source file for email addresses.
New option: --file-emails or --fe
email addresses in files are freeform text and are nearly impossible to
parse. Still, might as well try to do a somewhat acceptable job of
finding them. This code should find all addresses that are in the form
addr@domain.tld
The code assumes that up to 3 alphabetic words along with dashes, commas,
and periods that preceed the email address are a name.
If 3 words are found for the name, and one of the first two words are a
single letter and period, or just a single letter then the 3 words are use
as name otherwise the last 2 words are used.
Some variants that are shown correctly:
John Smith <jksmith@domain.org>
Random J. Developer <rjd@tld.com>
Random J. Developer (rjd@tld.com)
J. Random Developer rjd@tld.com
Variants that are shown nominally correctly:
Written by First Last (funny-addr@somecompany.com)
is shown as:
First Last <funny-addr@somecompany.com>
Variants that are shown incorrectly:
Some Really Long Name <srln@foo.bar>
MontaVista Software, Inc. <source@mvista.com>
are returned as:
Long Name <srln@foo.bar>
"Software, Inc" <source@mvista.com>
--roles and --rolestats show "(in file)" for matches.
For instance:
Without -file-emails:
$ ./scripts/get_maintainer.pl -f -nogit -roles net/core/netpoll.c
David S. Miller <davem@davemloft.net> (maintainer:NETWORKING [GENERAL])
linux-kernel@vger.kernel.org (open list)
With -fe:
$ ./scripts/get_maintainer.pl -f -fe -nogit -roles net/core/netpoll.c
David S. Miller <davem@davemloft.net> (maintainer:NETWORKING [GENERAL])
Matt Mackall <mpm@selenic.com> (in file)
Ingo Molnar <mingo@redhat.com> (in file)
linux-kernel@vger.kernel.org (open list)
netdev@vger.kernel.org (open list:NETWORKING [GENERAL])
The number of email addresses in the file in not limited. Neither is the
number of returned email addresses.
Signed-off-by: Joe Perches <joe@perches.com> Cc: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tetsuo Handa [Fri, 5 Mar 2010 21:42:56 +0000 (13:42 -0800)]
kernel/pid.c: update comment on find_task_by_pid_ns
tasklist_lock does protect the task and its pid, it can't go away. The
problem is that find_pid_ns() itself is unsafe without rcu lock, it can
race with copy_process()->free_pid(any_pid).
Protecting copy_process()->free_pid(any_pid) with tasklist_lock would make
it possible to call find_task_by_pid_ns() under tasklist safely, but we
don't do so because we are trying to get rid of the read_lock sites of
tasklist_lock.
Anton Blanchard [Fri, 5 Mar 2010 21:42:55 +0000 (13:42 -0800)]
panic: fix panic_timeout accuracy when running on a hypervisor
I've had some complaints about panic_timeout being wildly innacurate on
shared processor PowerPC partitions (a 3 minute panic_timeout taking 30
minutes).
The problem is we loop on mdelay(1) and with a 1ms in 10ms hypervisor
timeslice each of these will take 10ms (ie 10x) longer. I expect other
platforms with shared processor hypervisors will see the same issue.
This patch keeps the old behaviour if we have a panic_blink (only keyboard
LEDs right now) and does 1 second mdelays if we don't.
Signed-off-by: Anton Blanchard <anton@samba.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Simon Kagstrom [Fri, 5 Mar 2010 21:42:49 +0000 (13:42 -0800)]
lkdtm: add debugfs access and loosen KPROBE ties
Add adds a debugfs interface and additional failure modes to LKDTM to
provide similar functionality to the provoke-crash driver submitted here:
http://lwn.net/Articles/371208/
Crashes can now be induced either through module parameters (as before)
or through the debugfs interface as in provoke-crash.
The patch also provides a new "direct" interface, where KPROBES are not
used, i.e., the crash is invoked directly upon write to the debugfs
file. When built without KPROBES configured, only this mode is available.
Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net> Cc: M. Mohan Kumar <mohan@in.ibm.com> Cc: Americo Wang <xiyou.wangcong@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: "Eric W. Biederman" <ebiederm@xmission.com>, Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The only in tree external users of the symbol setup_max_cpus are in
arch/x86/. The files ./kernel/alternative.c, ./kernel/visws_quirks.c, and
./mm/kmemcheck/kmemcheck.c are all guarded by CONFIG_SMP being defined.
For this case the symbol is an unsigned int and declared as an extern in
include/linux/smp.h.
When CONFIG_SMP is not defined the symbol setup_max_cpus is
a constant value that is only used in init/main.c. Make the symbol
static for this case.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The macro any_online_node() is prone to producing sparse warnings due to
the local symbol 'node'. Since all the in-tree users are really
requesting the first online node (the mask argument is either
NODE_MASK_ALL or node_online_map) just use the first_online_node macro and
remove the any_online_node macro since there are no users.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Acked-by: David Rientjes <rientjes@google.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Cc: Milton Miller <miltonm@bga.com> Cc: Nathan Fontenot <nfont@austin.ibm.com> Cc: Geoff Levand <geoffrey.levand@am.sony.com> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: J. Bruce Fields <bfields@fieldses.org> Cc: Neil Brown <neilb@suse.de> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: David S. Miller <davem@davemloft.net> Cc: Benny Halevy <bhalevy@panasas.com> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Ricardo Labiaga <Ricardo.Labiaga@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
init/initramfs.c: fix "symbol shadows an earlier one" noise
The symbol 'count' is a local global variable in this file. The function
clean_rootfs() should use a different symbol name to prevent "symbol
shadows an earlier one" noise.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Randy Dunlap [Fri, 5 Mar 2010 21:42:35 +0000 (13:42 -0800)]
MFGPT: move clocksource menu
Move the CS5535 MFGPT hrtimer kconfig option to be with the other MFGPT
options. This makes it easier to find and also removes it from the main
"Device Drivers" menu, where it should not have been.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Andres Salomon <dilinger@collabora.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[akpm@linux-foundation.org: simplification] Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Richard Kennedy [Fri, 5 Mar 2010 21:42:30 +0000 (13:42 -0800)]
cpuidle menu: remove 8 bytes of padding on 64 bit builds
Reorder struct menu_device to remove 8 bytes of padding on 64 bit builds.
Size drops from 136 to 128 bytes, so possibly needing one fewer cache
lines.
Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> Cc: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Roel Kluin [Fri, 5 Mar 2010 21:42:28 +0000 (13:42 -0800)]
alpha: PTR_ERR overwrites -EINVAL in syscall osf_mount
The initial -EINVAL value is overwritten by `retval = PTR_ERR(name)'. If
this isn't an error pointer and typenr is not 1, 6 or 9, then this retval,
a pointer cast to a long, is returned.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Acked-by: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
FUJITA Tomonori [Fri, 5 Mar 2010 21:42:26 +0000 (13:42 -0800)]
frv: remove pci_dma_sync_single() and pci_dma_sync_sg()
No architecture except for frv has pci_dma_sync_single() and
pci_dma_sync_sg(). The APIs are deprecated.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Fri, 5 Mar 2010 21:42:25 +0000 (13:42 -0800)]
mm: add comment on swap_duplicate's error code
swap_duplicate()'s loop appears to miss out on returning the error code
from __swap_duplicate(), except when that's -ENOMEM. In fact this is
intentional: prior to -ENOMEM for swap_count_continuation,
swap_duplicate() was void (and the case only occurs when copy_one_pte()
hits a corrupt pte). But that's surprising behaviour, which certainly
deserves a comment.
nommu: get_user_pages(): pin last page on non-page-aligned start
The noMMU version of get_user_pages() fails to pin the last page when the
start address isn't page-aligned. The patch fixes this in a way that
makes find_extend_vma() congruent to its MMU cousin.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Fri, 5 Mar 2010 21:42:22 +0000 (13:42 -0800)]
vmscan: detect mapped file pages used only once
The VM currently assumes that an inactive, mapped and referenced file page
is in use and promotes it to the active list.
However, every mapped file page starts out like this and thus a problem
arises when workloads create a stream of such pages that are used only for
a short time. By flooding the active list with those pages, the VM
quickly gets into trouble finding eligible reclaim canditates. The result
is long allocation latencies and eviction of the wrong pages.
This patch reuses the PG_referenced page flag (used for unmapped file
pages) to implement a usage detection that scales with the speed of LRU
list cycling (i.e. memory pressure).
If the scanner encounters those pages, the flag is set and the page cycled
again on the inactive list. Only if it returns with another page table
reference it is activated. Otherwise it is reclaimed as 'not recently
used cache'.
This effectively changes the minimum lifetime of a used-once mapped file
page from a full memory cycle to an inactive list cycle, which allows it
to occur in linear streams without affecting the stable working set of the
system.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: OSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Fri, 5 Mar 2010 21:42:21 +0000 (13:42 -0800)]
vmscan: drop page_mapping_inuse()
page_mapping_inuse() is a historic predicate function for pages that are
about to be reclaimed or deactivated.
According to it, a page is in use when it is mapped into page tables OR
part of swap cache OR backing an mmapped file.
This function is used in combination with page_referenced(), which checks
for young bits in ptes and the page descriptor itself for the
PG_referenced bit. Thus, checking for unmapped swap cache pages is
meaningless as PG_referenced is not set for anonymous pages and unmapped
pages do not have young ptes. The test makes no difference.
Protecting file pages that are not by themselves mapped but are part of a
mapped file is also a historic leftover for short-lived things like the
exec() code in libc. However, the VM now does reference accounting and
activation of pages at unmap time and thus the special treatment on
reclaim is obsolete.
This patch drops page_mapping_inuse() and switches the two callsites to
use page_mapped() directly.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: OSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Fri, 5 Mar 2010 21:42:19 +0000 (13:42 -0800)]
vmscan: factor out page reference checks
The used-once mapped file page detection patchset.
It is meant to help workloads with large amounts of shortly used file
mappings, like rtorrent hashing a file or git when dealing with loose
objects (git gc on a bigger site?).
Right now, the VM activates referenced mapped file pages on first
encounter on the inactive list and it takes a full memory cycle to
reclaim them again. When those pages dominate memory, the system
no longer has a meaningful notion of 'working set' and is required
to give up the active list to make reclaim progress. Obviously,
this results in rather bad scanning latencies and the wrong pages
being reclaimed.
This patch makes the VM be more careful about activating mapped file
pages in the first place. The minimum granted lifetime without
another memory access becomes an inactive list cycle instead of the
full memory cycle, which is more natural given the mentioned loads.
This test resembles a hashing rtorrent process. Sequentially, 32MB
chunks of a file are mapped into memory, hashed (sha1) and unmapped
again. While this happens, every 5 seconds a process is launched and
its execution time taken:
I also tested kernbench with regular IO streaming in the background to
see whether the delayed activation of frequently used mapped file
pages had a negative impact on performance in the presence of pressure
on the inactive list. The patch made no significant difference in
timing, neither for kernbench nor for the streaming IO throughput.
The first patch submission raised concerns about the cost of the extra
faults for actually activated pages on machines that have no hardware
support for young page table entries.
I created an artificial worst case scenario on an ARM machine with
around 300MHz and 64MB of memory to figure out the dimensions
involved. The test would mmap a file of 20MB, then
1. touch all its pages to fault them in
2. force one full scan cycle on the inactive file LRU
-- old: mapping pages activated
-- new: mapping pages inactive
3. touch the mapping pages again
-- old and new: fault exceptions to set the young bits
4. force another full scan cycle on the inactive file LRU
5. touch the mapping pages one last time
-- new: fault exceptions to set the young bits
The test showed an overall increase of 6% in time over 100 iterations
of the above (old: ~212sec, new: ~225sec). 13 secs total overhead /
(100 * 5k pages), ignoring the execution time of the test itself,
makes for about 25us overhead for every page that gets actually
activated. Note:
1. File mapping the size of one third of main memory, _completely_
in active use across memory pressure - i.e., most pages referenced
within one LRU cycle. This should be rare to non-existant,
especially on such embedded setups.
2. Many huge activation batches. Those batches only occur when the
working set fluctuates. If it changes completely between every full
LRU cycle, you have problematic reclaim overhead anyway.
3. Access of activated pages at maximum speed: sequential loads from
every single page without doing anything in between. In reality,
the extra faults will get distributed between actual operations on
the data.
So even if a workload manages to get the VM into the situation of
activating a third of memory in one go on such a setup, it will take
2.2 seconds instead 2.1 without the patch.
Comparing the numbers (and my user-experience over several months),
I think this change is an overall improvement to the VM.
Patch 1 is only refactoring to break up that ugly compound conditional
in shrink_page_list() and make it easy to document and add new checks
in a readable fashion.
Patch 2 gets rid of the obsolete page_mapping_inuse(). It's not
strictly related to #3, but it was in the original submission and is a
net simplification, so I kept it.
Patch 3 implements used-once detection of mapped file pages.
This patch:
Moving the big conditional into its own predicate function makes the code
a bit easier to read and allows for better commenting on the checks
one-by-one.
This is just cleaning up, no semantics should have been changed.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: OSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Fri, 5 Mar 2010 21:42:16 +0000 (13:42 -0800)]
mm: document /sys/devices/system/node/nodeX
Add a bare description of what /sys/devices/system/node/nodeX is. Others
will follow in time but right now, none of that tree is documented. The
existence of this file might at least encourage people to document new
entries.
David Rientjes [Fri, 5 Mar 2010 21:42:14 +0000 (13:42 -0800)]
mm: suppress pfn range output for zones without pages
free_area_init_nodes() emits pfn ranges for all zones on the system.
There may be no pages on a higher zone, however, due to memory limitations
or the use of the mem= kernel parameter. For example:
Zone PFN ranges:
DMA 0x00000001 -> 0x00001000
DMA32 0x00001000 -> 0x00100000
Normal 0x00100000 -> 0x00100000
The implementation copies the previous zone's highest pfn, if any, as the
next zone's lowest pfn. If its highest pfn is then greater than the
amount of addressable memory, the upper memory limit is used instead.
Thus, both the lowest and highest possible pfn for higher zones without
memory may be the same.
The pfn range for zones without memory is now shown as "empty" instead.
Signed-off-by: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mel@csn.ul.ie> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/pm: force GFP_NOIO during suspend/hibernation and resume
There are quite a few GFP_KERNEL memory allocations made during
suspend/hibernation and resume that may cause the system to hang, because
the I/O operations they depend on cannot be completed due to the
underlying devices being suspended.
Avoid this problem by clearing the __GFP_IO and __GFP_FS bits in
gfp_allowed_mask before suspend/hibernation and restoring the original
values of these bits in gfp_allowed_mask durig the subsequent resume.
[akpm@linux-foundation.org: fix CONFIG_PM=n linkage] Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reported-by: Maxim Levitsky <maximlevitsky@gmail.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Fri, 5 Mar 2010 21:42:12 +0000 (13:42 -0800)]
mm/swapfile.c: fix swapon size off-by-one
There's an off-by-one disagreement between mkswap and swapon about the
meaning of swap_header last_page: mkswap (in all versions I've looked at:
util-linux-ng and BusyBox and old util-linux; probably as far back as
1999) consistently means the offset (in page units) of the last page of
the swap area, whereas kernel sys_swapon (as far back as 2.2 and 2.3)
strangely takes it to mean the size (in page units) of the swap area.
This disagreement is the safe way round; but it's worrying people, and
loses us one page of swap.
The fix is not just to add one to nr_good_pages: we need to get maxpages
(the size of the swap_map array) right before that; and though that is an
unsigned long, be careful not to overflow the unsigned int p->max which
later holds it (probably why header uses __u32 last_page instead of size).
Why did we subtract one from the maximum swp_offset to calculate maxpages?
Though it was probably me who made that change in 2.4.10, I don't get it:
and now we should be adding one (without risk of overflow in this case).
Fix the handling of swap_header badpages: it could have overrun the
swap_map when very large swap area used on a more limited architecture.
Remove pre-initializations of swap_header, nr_good_pages and maxpages:
those date from when sys_swapon was supporting other versions of header.
Reported-by: Nitin Gupta <ngupta@vflare.org> Reported-by: Jarkko Lavinen <jarkko.lavinen@nokia.com> Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Fri, 5 Mar 2010 21:42:10 +0000 (13:42 -0800)]
mm: remove VM_LOCK_RMAP code
When a VMA is in an inconsistent state during setup or teardown, the worst
that can happen is that the rmap code will not be able to find the page.
The mapping is in the process of being torn down (PTEs just got
invalidated by munmap), or set up (no PTEs have been instantiated yet).
It is also impossible for the rmap code to follow a pointer to an already
freed VMA, because the rmap code holds the anon_vma->lock, which the VMA
teardown code needs to take before the VMA is removed from the anon_vma
chain.
Hence, we should not need the VM_LOCK_RMAP locking at all.
Signed-off-by: Rik van Riel <riel@redhat.com> Cc: Nick Piggin <npiggin@suse.de> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Fri, 5 Mar 2010 21:42:09 +0000 (13:42 -0800)]
rmap: move exclusively owned pages to own anon_vma in do_wp_page()
When the parent process breaks the COW on a page, both the original which
is mapped at child and the new page which is mapped parent end up in that
same anon_vma. Generally this won't be a problem, but for some workloads
it could preserve the O(N) rmap scanning complexity.
A simple fix is to ensure that, when a page which is mapped child gets
reused in do_wp_page, because we already are the exclusive owner, the page
gets moved to our own exclusive child's anon_vma.
Signed-off-by: Rik van Riel <riel@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Fri, 5 Mar 2010 21:42:08 +0000 (13:42 -0800)]
rmap: remove obsolete check from __page_check_anon_rmap()
When an anonymous page is inherited from a parent process, the
vma->anon_vma can differ from the page anon_vma. This can trip up
__page_check_anon_rmap, which is indirectly called from do_swap_page().
Remove that obsolete check to prevent an oops.
Signed-off-by: Rik van Riel <riel@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rik van Riel [Fri, 5 Mar 2010 21:42:07 +0000 (13:42 -0800)]
mm: change anon_vma linking to fix multi-process server scalability issue
The old anon_vma code can lead to scalability issues with heavily forking
workloads. Specifically, each anon_vma will be shared between the parent
process and all its child processes.
In a workload with 1000 child processes and a VMA with 1000 anonymous
pages per process that get COWed, this leads to a system with a million
anonymous pages in the same anon_vma, each of which is mapped in just one
of the 1000 processes. However, the current rmap code needs to walk them
all, leading to O(N) scanning complexity for each page.
This can result in systems where one CPU is walking the page tables of
1000 processes in page_referenced_one, while all other CPUs are stuck on
the anon_vma lock. This leads to catastrophic failure for a benchmark
like AIM7, where the total number of processes can reach in the tens of
thousands. Real workloads are still a factor 10 less process intensive
than AIM7, but they are catching up.
This patch changes the way anon_vmas and VMAs are linked, which allows us
to associate multiple anon_vmas with a VMA. At fork time, each child
process gets its own anon_vmas, in which its COWed pages will be
instantiated. The parents' anon_vma is also linked to the VMA, because
non-COWed pages could be present in any of the children.
This reduces rmap scanning complexity to O(1) for the pages of the 1000
child processes, with O(N) complexity for at most 1/N pages in the system.
This reduces the average scanning cost in heavily forking workloads from
O(N) to 2.
The only real complexity in this patch stems from the fact that linking a
VMA to anon_vmas now involves memory allocations. This means vma_adjust
can fail, if it needs to attach a VMA to anon_vma structures. This in
turn means error handling needs to be added to the calling functions.
A second source of complexity is that, because there can be multiple
anon_vmas, the anon_vma linking in vma_adjust can no longer be done under
"the" anon_vma lock. To prevent the rmap code from walking up an
incomplete VMA, this patch introduces the VM_LOCK_RMAP VMA flag. This bit
flag uses the same slot as the NOMMU VM_MAPPED_COPY, with an ifdef in mm.h
to make sure it is impossible to compile a kernel that needs both symbolic
values for the same bitflag.
Some test results:
Without the anon_vma changes, when AIM7 hits around 9.7k users (on a test
box with 16GB RAM and not quite enough IO), the system ends up running
>99% in system time, with every CPU on the same anon_vma lock in the
pageout code.
With these changes, AIM7 hits the cross-over point around 29.7k users.
This happens with ~99% IO wait time, there never seems to be any spike in
system time. The anon_vma lock contention appears to be resolved.
[akpm@linux-foundation.org: cleanups] Signed-off-by: Rik van Riel <riel@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wu Fengguang [Fri, 5 Mar 2010 21:42:03 +0000 (13:42 -0800)]
readahead: introduce FMODE_RANDOM for POSIX_FADV_RANDOM
This fixes inefficient page-by-page reads on POSIX_FADV_RANDOM.
POSIX_FADV_RANDOM used to set ra_pages=0, which leads to poor performance:
a 16K read will be carried out in 4 _sync_ 1-page reads.
In other places, ra_pages==0 means
- it's ramfs/tmpfs/hugetlbfs/sysfs/configfs
- some IO error happened
where multi-page read IO won't help or should be avoided.
POSIX_FADV_RANDOM actually want a different semantics: to disable the
*heuristic* readahead algorithm, and to use a dumb one which faithfully
submit read IO for whatever application requests.
So introduce a flag FMODE_RANDOM for POSIX_FADV_RANDOM.
Note that the random hint is not likely to help random reads performance
noticeably. And it may be too permissive on huge request size (its IO
size is not limited by read_ahead_kb).
In Quentin's report (http://lkml.org/lkml/2009/12/24/145), the overall
(NFS read) performance of the application increased by 313%!
Tested-by: Quentin Barnes <qbarnes+nfs@yahoo-inc.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Andi Kleen <andi@firstfloor.org> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: <stable@kernel.org> [2.6.33.x] Cc: <qbarnes+nfs@yahoo-inc.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
KOSAKI Motohiro [Fri, 5 Mar 2010 21:42:00 +0000 (13:42 -0800)]
mm/migrate.c: kill anon local variable from migrate_page_copy
commit 01b1ae63c2 ("memcg: simple migration handling") removed
mem_cgroup_uncharge_cache_page() call from migrate_page_copy. Local
variable `anon' is now unused.
KOSAKI Motohiro [Fri, 5 Mar 2010 21:41:59 +0000 (13:41 -0800)]
mm/mempolicy.c: fix indentation of the comments of do_migrate_pages
Currently, do_migrate_pages() have very long comment and this is not
indent properly. I often misunderstand it is function starting commnents
and confused it.
this patch fixes it.
note: this patch doesn't break 80 column rule. I guess original
author intended this indentaion, but an accident corrupted it.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memory-hotplug: create /sys/firmware/memmap entry for new memory
A memmap is a directory in sysfs which includes 3 text files: start, end
and type. For example:
start: 0x100000
end: 0x7e7b1cff
type: System RAM
Interface firmware_map_add was not called explicitly. Remove it and add
function firmware_map_add_hotplug as hotplug interface of memmap.
Each memory entry has a memmap in sysfs, When we hot-add new memory, sysfs
does not export memmap entry for it. We add a call in function add_memory
to function firmware_map_add_hotplug.
Add a new function add_sysfs_fw_map_entry() to create memmap entry, it
will be called when initialize memmap and hot-add memory.
[akpm@linux-foundation.org: un-kernedoc a no longer kerneldoc comment] Signed-off-by: Shaohui Zheng <shaohui.zheng@intel.com> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: Yasunori Goto <y-goto@jp.fujitsu.com> Reviewed-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
int main(int argc, char** argv)
{
void* addr;
int ch;
int node;
struct bitmask *nmask = numa_allocate_nodemask();
int err;
int node_set = 0;
char buf[128];
KOSAKI Motohiro [Fri, 5 Mar 2010 21:41:55 +0000 (13:41 -0800)]
mm: restore zone->all_unreclaimable to independence word
commit e815af95 ("change all_unreclaimable zone member to flags") changed
all_unreclaimable member to bit flag. But it had an undesireble side
effect. free_one_page() is one of most hot path in linux kernel and
increasing atomic ops in it can reduce kernel performance a bit.
Thus, this patch revert such commit partially. at least
all_unreclaimable shouldn't share memory word with other zone flags.
Li Hong [Fri, 5 Mar 2010 21:41:54 +0000 (13:41 -0800)]
mm: remove free_hot_page()
free_hot_page() is just a wrapper around free_hot_cold_page() with
parameter 'cold = 0'. After adding a clear comment for
free_hot_cold_page(), it is reasonable to remove a level of call.
[akpm@linux-foundation.org: fix build] Signed-off-by: Li Hong <lihong.hi@gmail.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Li Ming Chun <macli@brc.ubc.ca> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Americo Wang <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Li Hong [Fri, 5 Mar 2010 21:41:53 +0000 (13:41 -0800)]
mm/page_alloc.c: adjust a call site to trace_mm_page_free_direct
Move a call of trace_mm_page_free_direct() from free_hot_page() to
free_hot_cold_page(). It is clearer and close to kmemcheck_free_shadow(),
as it is done in function __free_pages_ok().
Signed-off-by: Li Hong <lihong.hi@gmail.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Li Ming Chun <macli@brc.ubc.ca> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Li Hong [Fri, 5 Mar 2010 21:41:52 +0000 (13:41 -0800)]
mm/page_alloc.c: remove duplicate call to trace_mm_page_free_direct
trace_mm_page_free_direct() is called in function __free_pages(). But it
is called again in free_hot_page() if order == 0 and produce duplicate
records in trace file for mm_page_free_direct event. As below:
This patch removes the first call and adds a call to
trace_mm_page_free_direct() in __free_pages_ok().
Signed-off-by: Li Hong <lihong.hi@gmail.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Li Ming Chun <macli@brc.ubc.ca> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jiri Slaby [Fri, 5 Mar 2010 21:41:44 +0000 (13:41 -0800)]
mm: use rlimit helpers
Make sure compiler won't do weird things with limits. E.g. fetching them
twice may return 2 different values after writable limits are implemented.
I.e. either use rlimit helpers added in 3e10e716abf3c71bdb5d86b8f507f9e72236c9cd ("resource: add helpers for
fetching rlimits") or ACCESS_ONCE if not applicable.
projects / mv-sheeva.git / log