Commit Graph

242427 Commits

Author SHA1 Message Date
Alexandre Bounine
e15b4d687f rapidio: add RapidIO documentation
Add RapidIO documentation files as it was discussed earlier (see thread
http://marc.info/?l=linux-kernel&m=129202338918062&w=2)

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:41 -07:00
Alexandre Bounine
cd8b974fad rapidio: add new sysfs attributes
Add new sysfs attributes.

1. Routing information required to to reach the RIO device:
destid - device destination ID (real for for endpoint, route for switch)
hopcount - hopcount for maintenance requests (switches only)

2. device linking information:
lprev - name of device that precedes the given device in the enumeration
        or discovery order (displayed along with of the port to which it
        is attached).
lnext - names of devices (with corresponding port numbers) that are
        attached to the given device as next in the enumeration or
        discovery order (switches only)

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:41 -07:00
Changli Gao
cfaf346cb2 drivers/char/mem.c: clean up the code
Reduce the lines of code and simplify the logic.

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:40 -07:00
Julia Lawall
115bcd156a drivers/staging/tty/specialix.c: convert func_enter to func_exit
Convert calls to func_enter on leaving a function to func_exit.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
@@

- func_enter();
+ func_exit();
  return...;
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Roger Wolff <R.E.Wolff@BitWizard.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:39 -07:00
Julia Lawall
d9d691f584 drivers/tty/bfin_jtag_comm.c: avoid calling put_tty_driver on NULL
put_tty_driver calls tty_driver_kref_put on its argument, and then
tty_driver_kref_put calls kref_put on the address of a field of this
argument.  kref_put checks for NULL, but in this case the field is likely
to have some offset and so the result of taking its address will not be
NULL.  Labels are added to be able to skip over the call to put_tty_driver
when the argument will be NULL.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression *x;
@@

*if (x == NULL)
{ ...
* put_tty_driver(x);
  ...
  return ...;
}
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Torben Hohn <torbenh@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:39 -07:00
Niranjana Vishwanathapura
73210a135b drivers/char: add MSM smd_pkt driver
Add smd_pkt driver which provides device interface to smd packet ports.

Signed-off-by: Niranjana Vishwanathapura <nvishwan@codeaurora.org>
Cc: Brian Swetland <swetland@google.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: David Brown <davidb@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:38 -07:00
Sergey Senozhatsky
0dcf334c44 drivers/char/ipmi/ipmi_si_intf.c: fix cleanup_one_si section mismatch
commit d2478521af ("char/ipmi: fix OOPS caused by
pnp_unregister_driver on unregistered driver") introduced a section
mismatch by calling __exit cleanup_ipmi_si from __devinit init_ipmi_si.

Remove __exit annotation from cleanup_ipmi_si.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:38 -07:00
Kees Cook
5883f57ca0 proc: protect mm start_code/end_code in /proc/pid/stat
While mm->start_stack was protected from cross-uid viewing (commit
f83ce3e6b0 ("proc: avoid information leaks to non-privileged
processes")), the start_code and end_code values were not.  This would
allow the text location of a PIE binary to leak, defeating ASLR.

Note that the value "1" is used instead of "0" for a protected value since
"ps", "killall", and likely other readers of /proc/pid/stat, take
start_code of "0" to mean a kernel thread and will misbehave.  Thanks to
Brad Spengler for pointing this out.

Addresses CVE-2011-0726

Signed-off-by: Kees Cook <kees.cook@canonical.com>
Cc: <stable@kernel.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Eugene Teo <eugeneteo@kernel.sg>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Brad Spengler <spender@grsecurity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:37 -07:00
Alexey Dobriyan
312ec7e50c proc: make struct proc_dir_entry::namelen unsigned int
1. namelen is declared "unsigned short" which hints for "maybe space savings".
   Indeed in 2.4 struct proc_dir_entry looked like:

        struct proc_dir_entry {
                unsigned short low_ino;
                unsigned short namelen;

   Now, low_ino is "unsigned int", all savings were gone for a long time.
   "struct proc_dir_entry" is not that countless to worry about it's size,
   anyway.

2. converting from unsigned short to int/unsigned int can only create
   problems, we better play it safe.

Space is not really conserved, because of natural alignment for the next
field.  sizeof(struct proc_dir_entry) remains the same.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:37 -07:00
Jovi Zhang
fc3d8767b2 procfs: fix some wrong error code usage
[root@wei 1]# cat /proc/1/mem
cat: /proc/1/mem: No such process

error code -ESRCH is wrong in this situation.  Return -EPERM instead.

Signed-off-by: Jovi Zhang <bookjovi@gmail.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:36 -07:00
Aaro Koskinen
0db0c01b53 procfs: fix /proc/<pid>/maps heap check
The current code fails to print the "[heap]" marking if the heap is split
into multiple mappings.

Fix the check so that the marking is displayed in all possible cases:
	1. vma matches exactly the heap
	2. the heap vma is merged e.g. with bss
	3. the heap vma is splitted e.g. due to locked pages

Test cases. In all cases, the process should have mapping(s) with
[heap] marking:

	(1) vma matches exactly the heap

	#include <stdio.h>
	#include <unistd.h>
	#include <sys/types.h>

	int main (void)
	{
		if (sbrk(4096) != (void *)-1) {
			printf("check /proc/%d/maps\n", (int)getpid());
			while (1)
				sleep(1);
		}
		return 0;
	}

	# ./test1
	check /proc/553/maps
	[1] + Stopped                    ./test1
	# cat /proc/553/maps | head -4
	00008000-00009000 r-xp 00000000 01:00 3113640    /test1
	00010000-00011000 rw-p 00000000 01:00 3113640    /test1
	00011000-00012000 rw-p 00000000 00:00 0          [heap]
	4006f000-40070000 rw-p 00000000 00:00 0

	(2) the heap vma is merged

	#include <stdio.h>
	#include <unistd.h>
	#include <sys/types.h>

	char foo[4096] = "foo";
	char bar[4096];

	int main (void)
	{
		if (sbrk(4096) != (void *)-1) {
			printf("check /proc/%d/maps\n", (int)getpid());
			while (1)
				sleep(1);
		}
		return 0;
	}

	# ./test2
	check /proc/556/maps
	[2] + Stopped                    ./test2
	# cat /proc/556/maps | head -4
	00008000-00009000 r-xp 00000000 01:00 3116312    /test2
	00010000-00012000 rw-p 00000000 01:00 3116312    /test2
	00012000-00014000 rw-p 00000000 00:00 0          [heap]
	4004a000-4004b000 rw-p 00000000 00:00 0

	(3) the heap vma is splitted (this fails without the patch)

	#include <stdio.h>
	#include <unistd.h>
	#include <sys/mman.h>
	#include <sys/types.h>

	int main (void)
	{
		if ((sbrk(4096) != (void *)-1) && !mlockall(MCL_FUTURE) &&
		    (sbrk(4096) != (void *)-1)) {
			printf("check /proc/%d/maps\n", (int)getpid());
			while (1)
				sleep(1);
		}
		return 0;
	}

	# ./test3
	check /proc/559/maps
	[1] + Stopped                    ./test3
	# cat /proc/559/maps|head -4
	00008000-00009000 r-xp 00000000 01:00 3119108    /test3
	00010000-00011000 rw-p 00000000 01:00 3119108    /test3
	00011000-00012000 rw-p 00000000 00:00 0          [heap]
	00012000-00013000 rw-p 00000000 00:00 0          [heap]

It looks like the bug has been there forever, and since it only results in
some information missing from a procfile, it does not fulfil the -stable
"critical issue" criteria.

Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Reviewed-by: 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>
2011-03-23 19:46:36 -07:00
Konstantin Khlebnikov
51e031496d proc: hide kernel addresses via %pK in /proc/<pid>/stack
This file is readable for the task owner.  Hide kernel addresses from
unprivileged users, leave them function names and offsets.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Acked-by: Kees Cook <kees.cook@canonical.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:36 -07:00
Li Zefan
523fb486bf cpuset: hold callback_mutex in cpuset_post_clone()
Chaning cpuset->mems/cpuset->cpus should be protected under
callback_mutex.

cpuset_clone() doesn't follow this rule. It's ok because it's
called when creating and initializing a cgroup, but we'd better
hold the lock to avoid subtil break in the future.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:35 -07:00
Li Zefan
ee24d37977 cpuset: fix unchecked calls to NODEMASK_ALLOC()
Those functions that use NODEMASK_ALLOC() can't propagate errno
to users, but will fail silently.

Fix it by using a static nodemask_t variable for each function, and
those variables are protected by cgroup_mutex;

[akpm@linux-foundation.org: fix comment spelling, strengthen cgroup_lock comment]
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:35 -07:00
Li Zefan
c8163ca8af cpuset: remove unneeded NODEMASK_ALLOC() in cpuset_attach()
oldcs->mems_allowed is not modified during cpuset_attach(), so we don't
have to copy it to a buffer allocated by NODEMASK_ALLOC().  Just pass it
to cpuset_migrate_mm().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:34 -07:00
Li Zefan
9303e0c481 cpuset: remove unneeded NODEMASK_ALLOC() in cpuset_sprintf_memlist()
It's not necessary to copy cpuset->mems_allowed to a buffer allocated by
NODEMASK_ALLOC().  Just pass it to nodelist_scnprintf().

As spotted by Paul, a side effect is we fix a bug that the function can
return -ENOMEM but the caller doesn't expect negative return value.
Therefore change the return value of cpuset_sprintf_cpulist() and
cpuset_sprintf_memlist() from int to size_t.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:34 -07:00
David Rientjes
f9434ad155 memcg: give current access to memory reserves if it's trying to die
When a memcg is oom and current has already received a SIGKILL, then give
it access to memory reserves with a higher scheduling priority so that it
may quickly exit and free its memory.

This is identical to the global oom killer and is done even before
checking for panic_on_oom: a pending SIGKILL here while panic_on_oom is
selected is guaranteed to have come from userspace; the thread only needs
access to memory reserves to exit and thus we don't unnecessarily panic
the machine until the kernel has no last resort to free memory.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:33 -07:00
KAMEZAWA Hiroyuki
5a6475a4e1 memcg: fix leak on wrong LRU with FUSE
fs/fuse/dev.c::fuse_try_move_page() does

   (1) remove a page by ->steal()
   (2) re-add the page to page cache
   (3) link the page to LRU if it was not on LRU at (1)

This implies the page is _on_ LRU when it's added to radix-tree.  So, the
page is added to memory cgroup while it's on LRU.  because LRU is lazy and
no one flushs it.

This is the same behavior as SwapCache and needs special care as
 - remove page from LRU before overwrite pc->mem_cgroup.
 - add page to LRU after overwrite pc->mem_cgroup.

And we need to taking care of pagevec.

If PageLRU(page) is set before we add PCG_USED bit, the page will not be
added to memcg's LRU (in short period).  So, regardlress of PageLRU(page)
value before commit_charge(), we need to check PageLRU(page) after
commit_charge().

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=30432

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Balbir Singh <balbir@in.ibm.com>
Reported-by: Daniel Poelzleithner <poelzi@poelzi.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:33 -07:00
Michal Hocko
6cfddb2615 memcg: page_cgroup array is never stored on reserved pages
KAMEZAWA Hiroyuki noted that free_pages_cgroup doesn't have to check for
PageReserved because we never store the array on reserved pages (neither
alloc_pages_exact nor vmalloc use those pages).

So we can replace the check by a BUG_ON.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:33 -07:00
Michal Hocko
dde79e005a page_cgroup: reduce allocation overhead for page_cgroup array for CONFIG_SPARSEMEM
Currently we are allocating a single page_cgroup array per memory section
(stored in mem_section->base) when CONFIG_SPARSEMEM is selected.  This is
correct but memory inefficient solution because the allocated memory
(unless we fall back to vmalloc) is not kmalloc friendly:

        - 32b - 16384 entries (20B per entry) fit into 327680B so the
          524288B slab cache is used
        - 32b with PAE - 131072 entries with 2621440B fit into 4194304B
        - 64b - 32768 entries (40B per entry) fit into 2097152 cache

This is ~37% wasted space per memory section and it sumps up for the whole
memory.  On a x86_64 machine it is something like 6MB per 1GB of RAM.

We can reduce the internal fragmentation by using alloc_pages_exact which
allocates PAGE_SIZE aligned blocks so we will get down to <4kB wasted
memory per section which is much better.

We still need a fallback to vmalloc because we have no guarantees that we
will have a continuous memory of that size (order-10) later on during the
hotplug events.

[hannes@cmpxchg.org: do not define unused free_page_cgroup() without memory hotplug]
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:32 -07:00
Andrew Morton
4be4489fea mm/memcontrol.c: suppress uninitialized-var warning with older gcc's
mm/memcontrol.c: In function 'mem_cgroup_force_empty':
mm/memcontrol.c:2280: warning: 'flags' may be used uninitialized in this function

It's a false positive.

Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Greg Thelen <gthelen@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:32 -07:00
Johannes Weiner
7a159cc9d7 memcg: use native word page statistics counters
The statistic counters are in units of pages, there is no reason to make
them 64-bit wide on 32-bit machines.

Make them native words.  Since they are signed, this leaves 31 bit on
32-bit machines, which can represent roughly 8TB assuming a page size of
4k.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Greg Thelen <gthelen@google.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:31 -07:00
Johannes Weiner
e9f8974f2f memcg: break out event counters from other stats
For increasing and decreasing per-cpu cgroup usage counters it makes sense
to use signed types, as single per-cpu values might go negative during
updates.  But this is not the case for only-ever-increasing event
counters.

All the counters have been signed 64-bit so far, which was enough to count
events even with the sign bit wasted.

This patch:
- divides s64 counters into signed usage counters and unsigned
  monotonically increasing event counters.
- converts unsigned event counters into 'unsigned long' rather than
  'u64'.  This matches the type used by the /proc/vmstat event counters.

The next patch narrows the signed usage counters type (on 32-bit CPUs,
that is).

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Greg Thelen <gthelen@google.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:31 -07:00
Johannes Weiner
7ec99d6213 memcg: unify charge/uncharge quantities to units of pages
There is no clear pattern when we pass a page count and when we pass a
byte count that is a multiple of PAGE_SIZE.

We never charge or uncharge subpage quantities, so convert it all to page
counts.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:30 -07:00
Johannes Weiner
7ffd4ca7a2 memcg: convert uncharge batching from bytes to page granularity
We never uncharge subpage quantities.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:30 -07:00
Johannes Weiner
11c9ea4e80 memcg: convert per-cpu stock from bytes to page granularity
We never keep subpage quantities in the per-cpu stock.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:29 -07:00
Johannes Weiner
e7018b8d27 memcg: keep only one charge cancelling function
We have two charge cancelling functions: one takes a page count, the other
a page size.  The second one just divides the parameter by PAGE_SIZE and
then calls the first one.  This is trivial, no need for an extra function.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:29 -07:00
Johannes Weiner
bf1ff2635a memcg: remove memcg->reclaim_param_lock
The reclaim_param_lock is only taken around single reads and writes to
integer variables and is thus superfluous.  Drop it.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:29 -07:00
Johannes Weiner
4dc03de1b2 memcg: charged pages always have valid per-memcg zone info
page_cgroup_zoneinfo() will never return NULL for a charged page, remove
the check for it in mem_cgroup_get_reclaim_stat_from_page().

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:28 -07:00
Johannes Weiner
6b3ae58efc memcg: remove direct page_cgroup-to-page pointer
In struct page_cgroup, we have a full word for flags but only a few are
reserved.  Use the remaining upper bits to encode, depending on
configuration, the node or the section, to enable page_cgroup-to-page
lookups without a direct pointer.

This saves a full word for every page in a system with memory cgroups
enabled.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:28 -07:00
Johannes Weiner
5564e88ba6 memcg: condense page_cgroup-to-page lookup points
The per-cgroup LRU lists string up 'struct page_cgroup's.  To get from
those structures to the page they represent, a lookup is required.
Currently, the lookup is done through a direct pointer in struct
page_cgroup, so a lot of functions down the callchain do this lookup by
themselves instead of receiving the page pointer from their callers.

The next patch removes this pointer, however, and the lookup is no longer
that straight-forward.  In preparation for that, this patch only leaves
the non-optional lookups when coming directly from the LRU list and passes
the page down the stack.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:27 -07:00
Johannes Weiner
de3638d9cd memcg: fold __mem_cgroup_move_account into caller
It is one logical function, no need to have it split up.

Also, get rid of some checks from the inner function that ensured the
sanity of the outer function.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:27 -07:00
Johannes Weiner
97a6c37b34 memcg: change page_cgroup_zoneinfo signature
Instead of passing a whole struct page_cgroup to this function, let it
take only what it really needs from it: the struct mem_cgroup and the
page.

This has the advantage that reading pc->mem_cgroup is now done at the same
place where the ordering rules for this pointer are enforced and
explained.

It is also in preparation for removing the pc->page backpointer.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:26 -07:00
Johannes Weiner
ad324e9447 memcg: no uncharged pages reach page_cgroup_zoneinfo
This patch series removes the direct page pointer from struct page_cgroup,
which saves 20% of per-page memcg memory overhead (Fedora and Ubuntu
enable memcg per default, openSUSE apparently too).

The node id or section number is encoded in the remaining free bits of
pc->flags which allows calculating the corresponding page without the
extra pointer.

I ran, what I think is, a worst-case microbenchmark that just cats a large
sparse file to /dev/null, because it means that walking the LRU list on
behalf of per-cgroup reclaim and looking up pages from page_cgroups is
happening constantly and at a high rate.  But it made no measurable
difference.  A profile reported a 0.11% share of the new
lookup_cgroup_page() function in this benchmark.

This patch:

All callsites check PCG_USED before passing pc->mem_cgroup, so the latter
is never NULL.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:26 -07:00
Daisuke Nishimura
f212ad7cf9 memcg: add memcg sanity checks at allocating and freeing pages
Add checks at allocating or freeing a page whether the page is used (iow,
charged) from the view point of memcg.

This check may be useful in debugging a problem and we did similar checks
before the commit 52d4b9ac(memcg: allocate all page_cgroup at boot).

This patch adds some overheads at allocating or freeing memory, so it's
enabled only when CONFIG_DEBUG_VM is enabled.

Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:25 -07:00
Johannes Weiner
af4a662144 memcg: remove NULL check from lookup_page_cgroup() result
The page_cgroup array is set up before even fork is initialized.  I
seriously doubt that this code executes before the array is alloc'd.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:25 -07:00
Johannes Weiner
c14f35c70e memcg: remove impossible conditional when committing
No callsite ever passes a NULL pointer for a struct mem_cgroup * to the
committing function.  There is no need to check for it.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:24 -07:00
Johannes Weiner
3403968d7a memcg: remove unused page flag bitfield defines
These definitions have been unused since '4b3bde4 memcg: remove the
overhead associated with the root cgroup'.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:24 -07:00
Johannes Weiner
9d11ea9f16 memcg: simplify the way memory limits are checked
Since transparent huge pages, checking whether memory cgroups are below
their limits is no longer enough, but the actual amount of chargeable
space is important.

To not have more than one limit-checking interface, replace
memory_cgroup_check_under_limit() and memory_cgroup_check_margin() with a
single memory_cgroup_margin() that returns the chargeable space and leaves
the comparison to the callsite.

Soft limits are now checked the other way round, by using the already
existing function that returns the amount by which soft limits are
exceeded: res_counter_soft_limit_excess().

Also remove all the corresponding functions on the res_counter side that
are now no longer used.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:23 -07:00
Johannes Weiner
b7c6167848 memcg: soft limit reclaim should end at limit not below
Soft limit reclaim continues until the usage is below the current soft
limit, but the documented semantics are actually that soft limit reclaim
will push usage back until the soft limits are met again.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:23 -07:00
KAMEZAWA Hiroyuki
56039efa18 memcg: fix ugly initialization of return value is in caller
Remove initialization of vaiable in caller of memory cgroup function.
Actually, it's return value of memcg function but it's initialized in
caller.

Some memory cgroup uses following style to bring the result of start
function to the end function for avoiding races.

   mem_cgroup_start_A(&(*ptr))
   /* Something very complicated can happen here. */
   mem_cgroup_end_A(*ptr)

In some calls, *ptr should be initialized to NULL be caller.  But it's
ugly.  This patch fixes that *ptr is initialized by _start function.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:22 -07:00
KAMEZAWA Hiroyuki
6c191cd01a memcg: res_counter_read_u64(): fix potential races on 32-bit machines
res_counter_read_u64 reads u64 value without lock.  It's dangerous in a
32bit environment.  Add locking.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:22 -07:00
Akinobu Mita
61f2e7b0f4 bitops: remove minix bitops from asm/bitops.h
minix bit operations are only used by minix filesystem and useless by
other modules.  Because byte order of inode and block bitmaps is different
on each architecture like below:

m68k:
	big-endian 16bit indexed bitmaps

h8300, microblaze, s390, sparc, m68knommu:
	big-endian 32 or 64bit indexed bitmaps

m32r, mips, sh, xtensa:
	big-endian 32 or 64bit indexed bitmaps for big-endian mode
	little-endian bitmaps for little-endian mode

Others:
	little-endian bitmaps

In order to move minix bit operations from asm/bitops.h to architecture
independent code in minix filesystem, this provides two config options.

CONFIG_MINIX_FS_BIG_ENDIAN_16BIT_INDEXED is only selected by m68k.
CONFIG_MINIX_FS_NATIVE_ENDIAN is selected by the architectures which use
native byte order bitmaps (h8300, microblaze, s390, sparc, m68knommu,
m32r, mips, sh, xtensa).  The architectures which always use little-endian
bitmaps do not select these options.

Finally, we can remove minix bit operations from asm/bitops.h for all
architectures.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Michal Simek <monstr@monstr.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:22 -07:00
Akinobu Mita
3fca5af786 m68k: remove inline asm from minix_find_first_zero_bit
As a preparation for moving minix bit operations from asm/bitops.h to
architecture independent code in minix filesystem, this removes inline asm
from minix_find_first_zero_bit() for m68k.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:21 -07:00
Akinobu Mita
f312eff816 bitops: remove ext2 non-atomic bitops from asm/bitops.h
As the result of conversions, there are no users of ext2 non-atomic bit
operations except for ext2 filesystem itself.  Now we can put them into
architecture independent code in ext2 filesystem, and remove from
asm/bitops.h for all architectures.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:21 -07:00
Akinobu Mita
bb5cda3d70 dm: use little-endian bitops
As a preparation for removing ext2 non-atomic bit operations from
asm/bitops.h.  This converts ext2 non-atomic bit operations to
little-endian bit operations.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Alasdair Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:20 -07:00
Akinobu Mita
6b33aff368 md: use little-endian bitops
As a preparation for removing ext2 non-atomic bit operations from
asm/bitops.h.  This converts ext2 non-atomic bit operations to
little-endian bit operations.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:20 -07:00
Akinobu Mita
3cdc7125c3 ufs: use little-endian bitops
As a preparation for removing ext2 non-atomic bit operations from
asm/bitops.h.  This converts ext2 non-atomic bit operations to
little-endian bit operations.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:19 -07:00
Akinobu Mita
9ad1e1e405 udf: use little-endian bitops
As a preparation for removing ext2 non-atomic bit operations from
asm/bitops.h.  This converts ext2 non-atomic bit operations to
little-endian bit operations.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:19 -07:00
Akinobu Mita
b9b9144a53 reiserfs: use little-endian bitops
As a preparation for removing ext2 non-atomic bit operations from
asm/bitops.h.  This converts ext2 non-atomic bit operations to
little-endian bit operations.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:18 -07:00