Signed-off-by: Joe Perches <joe@perches.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Brian Swetland <swetland@google.com>
Cc: Pierre Ossman <drzeus-list@drzeus.cx>
Cc: San Mehat <san@android.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Cc: Pavel Machek <pavel@ucw.cz>
Cc: Brian Swetland <swetland@google.com>
Cc: Pierre Ossman <drzeus-list@drzeus.cx>
Cc: San Mehat <san@android.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

removed stuff not strictly necessary, and did a few cleanups.  It still
works :-).
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Cc: Brian Swetland <swetland@google.com>
Cc: Pierre Ossman <drzeus-list@drzeus.cx>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

and ought to result in some power saving.
Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Kishore Kadiyala <kishore.kadiyala@ti.com>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

instead of host->ocr_avail.
Signed-off-by: Balaji Rao <balajirrao@openmoko.org>
Cc: Andy Green <andy@openmoko.com>
Cc: Pierre Ossman <drzeus-mmc@drzeus.cx>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Robin Getz <rgetz@blackfin.uclinux.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

sections (such as data in Blackfin on-chip SRAM regions).
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Robin Getz <rgetz@blackfin.uclinux.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

sections (such as text in Blackfin on-chip SRAM regions).
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Robin Getz <rgetz@blackfin.uclinux.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

means there may be text or data that falls outside of the standard range
of the start/end text/data symbols.  Creating some helper functions allows
these non-standard ports to declare these regions without adversely
affecting anyone else.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Robin Getz <rgetz@blackfin.uclinux.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

 because it's was decided not to use it in previous conversation)

Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mark.  This struct is filled as a parameter to getrusage syscall. 
->ru_maxrss value is set to KBs which is the way it is done in BSD
systems.  /usr/bin/time (gnu time) application converts ->ru_maxrss to KBs
which seems to be incorrect behavior.  Maintainer of this util was
notified by me with the patch which corrects it and cc'ed.

To make this happen we extend struct signal_struct by two fields.  The
first one is ->maxrss which we use to store rss hiwater of the task.  The
second one is ->cmaxrss which we use to store highest rss hiwater of all
task childs.  These values are used in k_getrusage() to actually fill
->ru_maxrss.  k_getrusage() uses current rss hiwater value directly if mm
struct exists.

Note:
exec() clear mm->hiwater_rss, but doesn't clear sig->maxrss.
it is intetionally behavior. *BSD getrusage have exec() inheriting.

Test progmam and test case
===========================

getrusage.c
====
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <signal.h>

static void consume(int mega)
{
	size_t sz = mega * 1024 * 1024;
	void *ptr;

	ptr = malloc(sz);
	memset(ptr, 0, sz);
	usleep(1);  /* BSD rusage statics need to sleep 1 tick */
}

static void show_rusage(char *prefix)
{
	int err, err2;
	struct rusage rusage_self;
	struct rusage rusage_children;

	printf("%s: ", prefix);
	err = getrusage(RUSAGE_SELF, &rusage_self);
	if (!err)
		printf("self %ld ", rusage_self.ru_maxrss);
	err2 = getrusage(RUSAGE_CHILDREN, &rusage_children);
	if (!err2)
		printf("children %ld ", rusage_children.ru_maxrss);

	printf("\n");
}

int main(int argc, char** argv)
{
	int status;
	int c;
	int need_sleep_before_wait = 0;
	int consume_large_memory_at_first = 0;
	int create_child_at_first = 0;
	int sigign = 0;
	int create_child_before_exec = 0;
	int after_fork_test = 0;

	while ((c = getopt(argc, argv, "ceflsz")) != -1) {
		switch (c) {
		case 'c':
			create_child_at_first = 1;
			break;
		case 'e':
			create_child_before_exec = 1;
			break;
		case 'f':
			after_fork_test = 1;
			break;
		case 'l':
			consume_large_memory_at_first = 1;
			break;
		case 's':
			sigign = 1;
			break;
		case 'z':
			need_sleep_before_wait = 1;
			break;
		default:
			break;
		}
	}

	if (consume_large_memory_at_first)
		consume(100);

	if (create_child_at_first)
		system("./child -q");

	if (sigign)
		signal(SIGCHLD, SIG_IGN);

	if (fork()) {
		usleep(1);
		if (need_sleep_before_wait)
			sleep(3); /* children become zombie */
		show_rusage("pre_wait");
		wait(&status);
		show_rusage("post_wait");
	} else {
		usleep(1);
		show_rusage("fork");

		if (after_fork_test) {
			consume(30);
			show_rusage("fork2");
		}
		if (create_child_before_exec) {
			system("./child -lq");
			usleep(1);
			show_rusage("fork3");
		}

		execl("./child", "child", 0);
		exit(0);
	}

	return 0;
}

child.c
====
#include <sys/types.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>

static void consume(int mega)
{
	size_t sz = mega * 1024 * 1024;
	void *ptr;

	ptr = malloc(sz);
	memset(ptr, 0, sz);
	usleep(1);  /* BSD rusage statics need to sleep 1 tick */
}

static void show_rusage(char *prefix)
{
	int err, err2;
	struct rusage rusage_self;
	struct rusage rusage_children;

	printf("%s: ", prefix);
	err = getrusage(RUSAGE_SELF, &rusage_self);
	if (!err)
		printf("self %ld ", rusage_self.ru_maxrss);
	err2 = getrusage(RUSAGE_CHILDREN, &rusage_children);
	if (!err2)
		printf("children %ld ", rusage_children.ru_maxrss);

	printf("\n");

}

int main(int argc, char** argv)
{
	int status;
	int c;
	int silent = 0;
	int light_weight = 0;

	while ((c = getopt(argc, argv, "lq")) != -1) {
		switch (c) {
		case 'l':
			light_weight = 1;
			break;
		case 'q':
			silent = 1;
			break;
		default:
			break;
		}
	}

	if (!silent)
		show_rusage("exec");

	if (fork()) {
		if (light_weight)
			consume(400);
		else
			consume(700);
		wait(&status);
	} else {
		if (light_weight)
			consume(600);
		else
			consume(900);

		exit(0);
	}

	return 0;
}

testcase
========

1. inherit fork?

   test way:
   	% ./getrusage -lc

   bsd result:
   	fork line is "fork: self 0 children 0".

   	-> rusage sholdn't be inherit by fork.
	   (both RUSAGE_SELF and RUSAGE_CHILDREN)

2. inherit exec?

   test way:
   	% ./getrusage -lce

   bsd result:
   	fork3: self 103204 children 60000
	exec: self 103204 children 60000

   	fork3 and exec line are the same.

   	-> rusage shold be inherit by exec.
	   (both RUSAGE_SELF and RUSAGE_CHILDREN)

3. getrusage(RUSAGE_CHILDREN) collect grandchild statics?

   test way:
   	% ./getrusage

   bsd result:
   	post_wait line is about "post_wait: self 0 children 90000".

	-> RUSAGE_CHILDREN can collect grandchild.

4. zombie, but not waited children collect or not?

   test way:
   	% ./getrusage -z

   bsd result:
   	pre_wait line is "pre_wait: self 0 children 0".

	-> zombie child process (not waited-for child process)
	   isn't accounted.

5. SIG_IGN collect or not

   test way:
   	% ./getrusage -s

   bsd result:
   	post_wait line is "post_wait: self 0 children 0".

	-> if SIGCHLD is ignored, children isn't accounted.

6. fork and malloc
   test way:
   	% ./getrusage -lcf

   bsd result:
   	fork line is "fork: self 0 children 0".
   	fork2 line is about "fork: self 130000 children 0".

   	-> rusage sholdn't be inherit by fork.
	   (both RUSAGE_SELF and RUSAGE_CHILDREN)
	   but additional memory cunsumption cause right
	   maxrss calculation.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

--remove-duplicates will use the first email name or address presented
--noremove-duplicates will emit all names and addresses

--remove-duplicates is enabled by default

For instance:

$ ./scripts/get_maintainer.pl -f drivers/char/tty_ioctl.c
Greg Kroah-Hartman <gregkh@suse.de>
Alan Cox <alan@linux.intel.com>
Mike Frysinger <vapier@gentoo.org>
Alexey Dobriyan <adobriyan@gmail.com>
linux-kernel@vger.kernel.org

$ ./scripts/get_maintainer.pl -f --noremove-duplicates drivers/char/tty_ioctl.c
Greg Kroah-Hartman <gregkh@suse.de>
Alan Cox <alan@redhat.com>
Alan Cox <alan@linux.intel.com>
Alan Cox <alan@lxorguk.ukuu.org.uk>
Mike Frysinger <vapier@gentoo.org>
Alexey Dobriyan <adobriyan@gmail.com>
linux-kernel@vger.kernel.org

Using --remove-duplicates could eliminate multiple maintainers that
share the same name but not the same email address.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Don't make the command line also include --nomultiline in that case.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Convert address entries in .mailmap to first encountered address
Don't terminate shell commands with \n
Strip characters found after sign-offs by: name <address> [stripped]
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Added email_address_inuse to eliminate multiple maintainer entries
for the same email address, the first name encountered is used.

Used internal perl equivalents of shell cmd use of grep|cut|sort|uniq
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

should be performed to find maintainers.  default is 0 (all directory levels).

For instance:

MAINTAINERS currently has multiple M: and F: entries that match
net/netfilter/ipvs/ip_vs_app.c

IPVS
M:	Wensong Zhang <wensong@linux-vs.org>
M:	Simon Horman <horms@verge.net.au>
M:	Julian Anastasov <ja@ssi.bg>
[...]
F:	net/netfilter/ipvs/

NETFILTER/IPTABLES/IPCHAINS
[...]
M:	Patrick McHardy <kaber@trash.net>
[...]
F:	net/netfilter/

NETWORKING [GENERAL]
M:	"David S. Miller" <davem@davemloft.net>
[...]
F:	net/

THE REST
M:	Linus Torvalds <torvalds@linux-foundation.org>
[...]
F:	*/

Using this command will return all of those maintainers:
(except Linus unless --git-chief-maintainers is specified)

$ ./scripts/get_maintainer.pl --nogit -nol \
	-f net/netfilter/ipvs/ip_vs_app.c
Julian Anastasov <ja@ssi.bg>
Simon Horman <horms@verge.net.au>
Wensong Zhang <wensong@linux-vs.org>
Patrick McHardy <kaber@trash.net>
David S. Miller <davem@davemloft.net>

Adding --pattern-depth=1 will match at the deepest level
$ ./scripts/get_maintainer.pl --nogit -nol --pattern-depth=1 \
	-f net/netfilter/ipvs/ip_vs_app.c
Julian Anastasov <ja@ssi.bg>
Simon Horman <horms@verge.net.au>
Wensong Zhang <wensong@linux-vs.org>

Adding --pattern-depth=2 will match at the deepest level and 1 higher
$ ./scripts/get_maintainer.pl --nogit -nol --pattern-depth=2 \
	-f net/netfilter/ipvs/ip_vs_app.c
Julian Anastasov <ja@ssi.bg>
Simon Horman <horms@verge.net.au>
Wensong Zhang <wensong@linux-vs.org>
Patrick McHardy <kaber@trash.net>

and so on.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

of appearance in the normally alphabetic section order of
the MAINTAINERS file.

For instance, finding the maintainer for drivers/scsi/wd7000.c
would first find "SCSI SUBSYSTEM", then "WD7000 SCSI SUBSYSTEM",
then "THE REST".

before patch:

$ ./scripts/get_maintainer.pl --nogit -f drivers/scsi/wd7000.c
James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Miroslav Zagorac <zaga@fly.cc.fer.hr>
linux-scsi@vger.kernel.org
linux-kernel@vger.kernel.org

get_maintainer.pl now selects matched sections by longest pattern match.
Longest is the number of "/"s and any specific file pattern.

This changes the example output order of MAINTAINERS to whatever is
selected in "WD7000 SUBSYSTEM", then "SCSI SYSTEM", then "THE REST".

after patch:

$ ./scripts/get_maintainer.pl --nogit -f drivers/scsi/wd7000.c
Miroslav Zagorac <zaga@fly.cc.fer.hr>
James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
linux-scsi@vger.kernel.org
linux-kernel@vger.kernel.org
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

ability to include signatories of commits that are modified by
a particular patch.

Vegard Nossum did something similar once.
http://lkml.org/lkml/2008/5/29/449

The modified script looks the commits for all lines in the
patch, and includes the "-by:" signatories for those commits.
It uses the same git-min-percent, git-max-maintainers, and
git-min-signatures options.  git-since is ignored.

It can be used independently from the --git default, so
        ./scripts/get_maintainers.pl --nogit --git-blame <patch>
or
        ./scripts/get_maintainers.pl --nogit --git-blame -f <file>
is acceptable.

If used with -f <file>, all lines/commits for the file are
checked.

--git-blame can be slow if used with -f <file>
--git-blame does not work with -f <directory>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Cc: Joe Perches <joe@perches.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

many cases, see below examples:

1: hotplug_cfd() can free cfd->cpumask, the system will crash if the
   cpu's cfd still in the call_function list:


      CPU A:                         CPU B

 smp_call_function_many()	    ......
   cpu_down()                      ......
  hotplug_cfd() ->                 ......
 free_cpumask_var(cfd->cpumask)  (receive function IPI interrupte)
                                /* read cfd->cpumask */
                          generic_smp_call_function_interrupt() ->
                         cpumask_test_and_clear_cpu(cpu, data->cpumask)

                         	CRASH!!!

2: It's not handle call_function list when cpu down, It's will lead to
   dead-wait if other path is waiting this cpu to execute function

    CPU A:                           CPU B

 smp_call_function_many(wait=0)
        ......			    CPU B down
   smp_call_function_many() -->  (cpu down before recevie function
    csd_lock(&data->csd);         IPI interrupte)

    DEAD-WAIT!!!!

  So, CPU A will dead-wait in csd_lock(), the same as
  smp_call_function_single()
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

the next patch (generic-ipi: fix the race between
generic_smp_call_function_*() and hotplug_cfd()) actually makes to that
function.

Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

generic_smp_call_function_interrupt(), It's no need to disable preempt,
beacuse we must call generic_smp_call_function_interrupt() with interrupts
disabled
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

> Delivery to the following recipient failed permanently:
>
>      linware@sh.cvut.cz
>
> Technical details of permanent failure:
> Google tried to deliver your message, but it was rejected by the recipient
> domain. We recommend contacting the other email provider for further
> information about the cause of this error. The error that the other server
> returned was: 450 450 <linware@sh.cvut.cz>: Recipient address rejected:
> undeliverable address: unknown user: "linware" (state 14).

Cc: Petr Vandrovec <vandrove@vc.cvut.cz>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

the account file.  In addition, every once in a while one of the exiting
processes checks whether there's enough free space for the log.

SELinux policy may or may not allow the exiting process to stat the fs. 
So unsuspecting processes start generating AVC denials just because
someone enabled process accounting.

For these filesystem operations, the exiting process's credentials should
be temporarily switched to that of the process which enabled accounting,
because it's really that process which wanted to have the accounting
information logged.
Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

to the line immediately after the closing function brace line.

Also, move the __initcall() similarly.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

BUILD_BUG_ON() useless, as that doesn't produce any diagnostic if the
controlling expression isn't really constant.  Instead, this patch makes
it so that a bit field gets used here.  Consequently, those uses where the
condition isn't really constant now also need fixing.

Note that in the gfp.h, kmemcheck.h, and virtio_config.h cases
MAYBE_BUILD_BUG_ON() really just serves documentation purposes - even if
the expression is compile time constant (__builtin_constant_p() yields
true), the array is still deemed of variable length by gcc, and hence the
whole expression doesn't have the intended effect.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

immediately after the closing function brace line.

Also, mark_buffer_async_write_endio() and do_thaw_all() are not used
elsewhere so they should be marked as static.

In addition, file_fsync() is actually in fs/sync.c so move the EXPORT* to
that file.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

writing.  This is causing the user's desktop session to become unusable.

Jan tracked the cause of this down to UDF inode reclaim blocking:

gnome-screens D ffff810006d1d598     0 20686      1
 ffff810006d1d508 0000000000000082 ffff810037db6718 0000000000000800
 ffff810006d1d488 ffffffff807e4280 ffffffff807e4280 ffff810006d1a580
 ffff8100bccbc140 ffff810006d1a8c0 0000000006d1d4e8 ffff810006d1a8c0
Call Trace:
 [<ffffffff804477f3>] io_schedule+0x63/0xa5
 [<ffffffff802c2587>] sync_buffer+0x3b/0x3f
 [<ffffffff80447d2a>] __wait_on_bit+0x47/0x79
 [<ffffffff80447dc6>] out_of_line_wait_on_bit+0x6a/0x77
 [<ffffffff802c24f6>] __wait_on_buffer+0x1f/0x21
 [<ffffffff802c442a>] __bread+0x70/0x86
 [<ffffffff88de9ec7>] :udf:udf_tread+0x38/0x3a
 [<ffffffff88de0fcf>] :udf:udf_update_inode+0x4d/0x68c
 [<ffffffff88de26e1>] :udf:udf_write_inode+0x1d/0x2b
 [<ffffffff802bcf85>] __writeback_single_inode+0x1c0/0x394
 [<ffffffff802bd205>] write_inode_now+0x7d/0xc4
 [<ffffffff88de2e76>] :udf:udf_clear_inode+0x3d/0x53
 [<ffffffff802b39ae>] clear_inode+0xc2/0x11b
 [<ffffffff802b3ab1>] dispose_list+0x5b/0x102
 [<ffffffff802b3d35>] shrink_icache_memory+0x1dd/0x213
 [<ffffffff8027ede3>] shrink_slab+0xe3/0x158
 [<ffffffff8027fbab>] try_to_free_pages+0x177/0x232
 [<ffffffff8027a578>] __alloc_pages+0x1fa/0x392
 [<ffffffff802951fa>] alloc_page_vma+0x176/0x189
 [<ffffffff802822d8>] __do_fault+0x10c/0x417
 [<ffffffff80284232>] handle_mm_fault+0x466/0x940
 [<ffffffff8044b922>] do_page_fault+0x676/0xabf

This blocks with iprune_mutex held, which then blocks other reclaimers:

X             D ffff81009d47c400     0 17285  14831
 ffff8100844f3728 0000000000000086 0000000000000000 ffff81000000e288
 ffff81000000da00 ffffffff807e4280 ffffffff807e4280 ffff81009d47c400
 ffffffff805ff890 ffff81009d47c740 00000000844f3808 ffff81009d47c740
Call Trace:
 [<ffffffff80447f8c>] __mutex_lock_slowpath+0x72/0xa9
 [<ffffffff80447e1a>] mutex_lock+0x1e/0x22
 [<ffffffff802b3ba1>] shrink_icache_memory+0x49/0x213
 [<ffffffff8027ede3>] shrink_slab+0xe3/0x158
 [<ffffffff8027fbab>] try_to_free_pages+0x177/0x232
 [<ffffffff8027a578>] __alloc_pages+0x1fa/0x392
 [<ffffffff8029507f>] alloc_pages_current+0xd1/0xd6
 [<ffffffff80279ac0>] __get_free_pages+0xe/0x4d
 [<ffffffff802ae1b7>] __pollwait+0x5e/0xdf
 [<ffffffff8860f2b4>] :nvidia:nv_kern_poll+0x2e/0x73
 [<ffffffff802ad949>] do_select+0x308/0x506
 [<ffffffff802adced>] core_sys_select+0x1a6/0x254
 [<ffffffff802ae0b7>] sys_select+0xb5/0x157

Now I think the main problem is having the filesystem block (and do IO) in
inode reclaim.  The problem is that this doesn't get accounted well and
penalizes a random allocator with a big latency spike caused by work
generated from elsewhere.

I think the best idea would be to avoid this.  By design if possible, or
by deferring the hard work to an asynchronous context.  If the latter,
then the fs would probably want to throttle creation of new work with
queue size of the deferred work, but let's not get into those details.

Anyway, the other obvious thing we looked at is the iprune_mutex which is
causing the cascading blocking.  We could turn this into an rwsem to
improve concurrency.  It is unreasonable to totally ban all potentially
slow or blocking operations in inode reclaim, so I think this is a cheap
way to get a small improvement.

This doesn't solve the whole problem of course.  The process doing inode
reclaim will still take the latency hit, and concurrent processes may end
up contending on filesystem locks.  So fs developers should keep these
problems in mind.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Jan Kara <jack@ucw.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

No need for redeclaration.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

printk_once() macro matches the intent of the code better, and allows the
compiler to generate smaller code; eg a typical callsite with gcc 4.3.3 on
i386:

add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-6 (-6)
function                                     old     new   delta
static.__print_once                            4       1      -3
get_cpu_vendor                               146     143      -3

Saving 6 bytes of object size per callsite by slightly improving the
readability of the source seems like a win to me.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

supervising init daemon such as Upstart.

While a daemon will normally do this as part of the process of becoming a
daemon, it is rare for its children to do so.  When the children do, it is
nearly always a sign that the child should be considered detached from the
parent and not supervised along with it.

The poster-child example is OpenSSH; the per-login children call setsid()
so that they may control the pty connected to them.  If the primary daemon
dies or is restarted, we do not want to consider the per-login children
and want to respawn the primary daemon without killing the children.

This patch adds a new PROC_SID_EVENT and associated structure to the
proc_event event_data union, it arranges for this to be emitted when the
special PIDTYPE_SID pid is set.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Scott James Remnant <scott@ubuntu.com>
Acked-by: Matt Helsley <matthltc@us.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

revectoring user-triggerable function pointers.

This is derived from the grsecurity patch, although generated from scratch
because it's simpler than extracting the changes from there.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Documentation/.
Signed-off-by: Ladinu Chandrasinghe <ladinu.pub@gmail.com>
Signed-off-by: Trevor Keith <tsrk@tsrk.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

only 3 bytes - pwm_config[3] is out of range.

Since this code path is never called with ix == 3 (the device has no PWM4
output) this doesn't change anything in practice.  But to encourage
testing with Parfait, lets make the warning go away...
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

reasons are below:

1: add a new interface for cpumask named cpumask_test_and_clear_cpu(),
   it can atomically test and clear specific cpu, we can use it instead
   of cpumask_test_cpu() and cpumask_clear_cpu() and no need data->lock
   to protect those in generic_smp_call_function_interrupt().

2: in smp_call_function_many(), after csd_lock() return, the current's
   cfd_data is deleted from call_function list, so it not have race
   between other cpus, then cfs_data is only used in
   smp_call_function_many() that must disable preemption and not from
   a hardware interrupthandler or from a bottom half handler to call,
   only the correspond cpu can use it, so it not have race in current
   cpu, no need cfs_data->lock to protect it.

3: after 1 and 2, cfs_data->lock is only use to protect cfs_data->refs in
   generic_smp_call_function_interrupt(), so we can define cfs_data->refs
   to atomic_t, and no need cfs_data->lock any more.
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

written to the proc file.
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

takes an allocated subprocess_info structure, which it passes to a
workqueue, and then passes it to a kernel thread which it creates, after
which it calls complete to signal to the caller of
call_usermodehelper_exec() that it can free the subprocess_info struct.

But since we use that structure in the created thread, we can't call
complete from __call_usermodehelper(), which is where we create the kernel
thread.  We need to call complete() from within the kernel thread and then
not use subprocess_info afterward in the case of UMH_WAIT_EXEC.  Tested
successfully by me.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>