<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/include/linux/cpuset.h, branch v3.18.5</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v3.18.5</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v3.18.5'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2014-10-10T11:24:40Z</updated>
<entry>
<title>Merge branch 'for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup</title>
<updated>2014-10-10T11:24:40Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-10-10T11:24:40Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b211e9d7c861bdb37b86d6384da9edfb80949ceb'/>
<id>urn:sha1:b211e9d7c861bdb37b86d6384da9edfb80949ceb</id>
<content type='text'>
Pull cgroup updates from Tejun Heo:
 "Nothing too interesting.  Just a handful of cleanup patches"

* 'for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  Revert "cgroup: remove redundant variable in cgroup_mount()"
  cgroup: remove redundant variable in cgroup_mount()
  cgroup: fix missing unlock in cgroup_release_agent()
  cgroup: remove CGRP_RELEASABLE flag
  perf/cgroup: Remove perf_put_cgroup()
  cgroup: remove redundant check in cgroup_ino()
  cpuset: simplify proc_cpuset_show()
  cgroup: simplify proc_cgroup_show()
  cgroup: use a per-cgroup work for release agent
  cgroup: remove bogus comments
  cgroup: remove redundant code in cgroup_rmdir()
  cgroup: remove some useless forward declarations
  cgroup: fix a typo in comment.
</content>
</entry>
<entry>
<title>cpuset: PF_SPREAD_PAGE and PF_SPREAD_SLAB should be atomic flags</title>
<updated>2014-09-25T02:16:06Z</updated>
<author>
<name>Zefan Li</name>
<email>lizefan@huawei.com</email>
</author>
<published>2014-09-25T01:41:02Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2ad654bc5e2b211e92f66da1d819e47d79a866f0'/>
<id>urn:sha1:2ad654bc5e2b211e92f66da1d819e47d79a866f0</id>
<content type='text'>
When we change cpuset.memory_spread_{page,slab}, cpuset will flip
PF_SPREAD_{PAGE,SLAB} bit of tsk-&gt;flags for each task in that cpuset.
This should be done using atomic bitops, but currently we don't,
which is broken.

Tetsuo reported a hard-to-reproduce kernel crash on RHEL6, which happened
when one thread tried to clear PF_USED_MATH while at the same time another
thread tried to flip PF_SPREAD_PAGE/PF_SPREAD_SLAB. They both operate on
the same task.

Here's the full report:
https://lkml.org/lkml/2014/9/19/230

To fix this, we make PF_SPREAD_PAGE and PF_SPREAD_SLAB atomic flags.

v4:
- updated mm/slab.c. (Fengguang Wu)
- updated Documentation.

Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Miao Xie &lt;miaox@cn.fujitsu.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Fixes: 950592f7b991 ("cpusets: update tasks' page/slab spread flags in time")
Cc: &lt;stable@vger.kernel.org&gt; # 2.6.31+
Reported-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
</content>
</entry>
<entry>
<title>cpuset: simplify proc_cpuset_show()</title>
<updated>2014-09-18T17:27:23Z</updated>
<author>
<name>Zefan Li</name>
<email>lizefan@huawei.com</email>
</author>
<published>2014-09-18T08:03:36Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=52de4779f201758ddcf37360f09a16895756e708'/>
<id>urn:sha1:52de4779f201758ddcf37360f09a16895756e708</id>
<content type='text'>
Use the ONE macro instead of REG, and we can simplify proc_cpuset_show().

Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
</content>
</entry>
<entry>
<title>mm: page_alloc: use jump labels to avoid checking number_of_cpusets</title>
<updated>2014-06-04T23:54:08Z</updated>
<author>
<name>Mel Gorman</name>
<email>mgorman@suse.de</email>
</author>
<published>2014-06-04T23:10:08Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=664eeddeef6539247691197c1ac124d4aa872ab6'/>
<id>urn:sha1:664eeddeef6539247691197c1ac124d4aa872ab6</id>
<content type='text'>
If cpusets are not in use then we still check a global variable on every
page allocation.  Use jump labels to avoid the overhead.

Signed-off-by: Mel Gorman &lt;mgorman@suse.de&gt;
Reviewed-by: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Jan Kara &lt;jack@suse.cz&gt;
Cc: Michal Hocko &lt;mhocko@suse.cz&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Dave Hansen &lt;dave.hansen@intel.com&gt;
Cc: Theodore Ts'o &lt;tytso@mit.edu&gt;
Cc: "Paul E. McKenney" &lt;paulmck@linux.vnet.ibm.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mm: optimize put_mems_allowed() usage</title>
<updated>2014-04-03T23:20:58Z</updated>
<author>
<name>Mel Gorman</name>
<email>mgorman@suse.de</email>
</author>
<published>2014-04-03T21:47:24Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=d26914d11751b23ca2e8747725f2cae10c2f2c1b'/>
<id>urn:sha1:d26914d11751b23ca2e8747725f2cae10c2f2c1b</id>
<content type='text'>
Since put_mems_allowed() is strictly optional, its a seqcount retry, we
don't need to evaluate the function if the allocation was in fact
successful, saving a smp_rmb some loads and comparisons on some relative
fast-paths.

Since the naming, get/put_mems_allowed() does suggest a mandatory
pairing, rename the interface, as suggested by Mel, to resemble the
seqcount interface.

This gives us: read_mems_allowed_begin() and read_mems_allowed_retry(),
where it is important to note that the return value of the latter call
is inverted from its previous incarnation.

Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Signed-off-by: Mel Gorman &lt;mgorman@suse.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>cpuset: Fix potential deadlock w/ set_mems_allowed</title>
<updated>2013-11-06T11:40:27Z</updated>
<author>
<name>John Stultz</name>
<email>john.stultz@linaro.org</email>
</author>
<published>2013-10-07T22:52:00Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=db751fe3ea6880ff5ac5abe60cb7b80deb5a4140'/>
<id>urn:sha1:db751fe3ea6880ff5ac5abe60cb7b80deb5a4140</id>
<content type='text'>
After adding lockdep support to seqlock/seqcount structures,
I started seeing the following warning:

[    1.070907] ======================================================
[    1.072015] [ INFO: SOFTIRQ-safe -&gt; SOFTIRQ-unsafe lock order detected ]
[    1.073181] 3.11.0+ #67 Not tainted
[    1.073801] ------------------------------------------------------
[    1.074882] kworker/u4:2/708 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
[    1.076088]  (&amp;p-&gt;mems_allowed_seq){+.+...}, at: [&lt;ffffffff81187d7f&gt;] new_slab+0x5f/0x280
[    1.077572]
[    1.077572] and this task is already holding:
[    1.078593]  (&amp;(&amp;q-&gt;__queue_lock)-&gt;rlock){..-...}, at: [&lt;ffffffff81339f03&gt;] blk_execute_rq_nowait+0x53/0xf0
[    1.080042] which would create a new lock dependency:
[    1.080042]  (&amp;(&amp;q-&gt;__queue_lock)-&gt;rlock){..-...} -&gt; (&amp;p-&gt;mems_allowed_seq){+.+...}
[    1.080042]
[    1.080042] but this new dependency connects a SOFTIRQ-irq-safe lock:
[    1.080042]  (&amp;(&amp;q-&gt;__queue_lock)-&gt;rlock){..-...}
[    1.080042] ... which became SOFTIRQ-irq-safe at:
[    1.080042]   [&lt;ffffffff810ec179&gt;] __lock_acquire+0x5b9/0x1db0
[    1.080042]   [&lt;ffffffff810edfe5&gt;] lock_acquire+0x95/0x130
[    1.080042]   [&lt;ffffffff818968a1&gt;] _raw_spin_lock+0x41/0x80
[    1.080042]   [&lt;ffffffff81560c9e&gt;] scsi_device_unbusy+0x7e/0xd0
[    1.080042]   [&lt;ffffffff8155a612&gt;] scsi_finish_command+0x32/0xf0
[    1.080042]   [&lt;ffffffff81560e91&gt;] scsi_softirq_done+0xa1/0x130
[    1.080042]   [&lt;ffffffff8133b0f3&gt;] blk_done_softirq+0x73/0x90
[    1.080042]   [&lt;ffffffff81095dc0&gt;] __do_softirq+0x110/0x2f0
[    1.080042]   [&lt;ffffffff81095fcd&gt;] run_ksoftirqd+0x2d/0x60
[    1.080042]   [&lt;ffffffff810bc506&gt;] smpboot_thread_fn+0x156/0x1e0
[    1.080042]   [&lt;ffffffff810b3916&gt;] kthread+0xd6/0xe0
[    1.080042]   [&lt;ffffffff818980ac&gt;] ret_from_fork+0x7c/0xb0
[    1.080042]
[    1.080042] to a SOFTIRQ-irq-unsafe lock:
[    1.080042]  (&amp;p-&gt;mems_allowed_seq){+.+...}
[    1.080042] ... which became SOFTIRQ-irq-unsafe at:
[    1.080042] ...  [&lt;ffffffff810ec1d3&gt;] __lock_acquire+0x613/0x1db0
[    1.080042]   [&lt;ffffffff810edfe5&gt;] lock_acquire+0x95/0x130
[    1.080042]   [&lt;ffffffff810b3df2&gt;] kthreadd+0x82/0x180
[    1.080042]   [&lt;ffffffff818980ac&gt;] ret_from_fork+0x7c/0xb0
[    1.080042]
[    1.080042] other info that might help us debug this:
[    1.080042]
[    1.080042]  Possible interrupt unsafe locking scenario:
[    1.080042]
[    1.080042]        CPU0                    CPU1
[    1.080042]        ----                    ----
[    1.080042]   lock(&amp;p-&gt;mems_allowed_seq);
[    1.080042]                                local_irq_disable();
[    1.080042]                                lock(&amp;(&amp;q-&gt;__queue_lock)-&gt;rlock);
[    1.080042]                                lock(&amp;p-&gt;mems_allowed_seq);
[    1.080042]   &lt;Interrupt&gt;
[    1.080042]     lock(&amp;(&amp;q-&gt;__queue_lock)-&gt;rlock);
[    1.080042]
[    1.080042]  *** DEADLOCK ***

The issue stems from the kthreadd() function calling set_mems_allowed
with irqs enabled. While its possibly unlikely for the actual deadlock
to trigger, a fix is fairly simple: disable irqs before taking the
mems_allowed_seq lock.

Signed-off-by: John Stultz &lt;john.stultz@linaro.org&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Acked-by: Li Zefan &lt;lizefan@huawei.com&gt;
Cc: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/1381186321-4906-4-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs</title>
<updated>2013-05-02T00:51:54Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-05-02T00:51:54Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=20b4fb485227404329e41ad15588afad3df23050'/>
<id>urn:sha1:20b4fb485227404329e41ad15588afad3df23050</id>
<content type='text'>
Pull VFS updates from Al Viro,

Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).

7kloc removed.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
  don't bother with deferred freeing of fdtables
  proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
  proc: Make the PROC_I() and PDE() macros internal to procfs
  proc: Supply a function to remove a proc entry by PDE
  take cgroup_open() and cpuset_open() to fs/proc/base.c
  ppc: Clean up scanlog
  ppc: Clean up rtas_flash driver somewhat
  hostap: proc: Use remove_proc_subtree()
  drm: proc: Use remove_proc_subtree()
  drm: proc: Use minor-&gt;index to label things, not PDE-&gt;name
  drm: Constify drm_proc_list[]
  zoran: Don't print proc_dir_entry data in debug
  reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
  proc: Supply an accessor for getting the data from a PDE's parent
  airo: Use remove_proc_subtree()
  rtl8192u: Don't need to save device proc dir PDE
  rtl8187se: Use a dir under /proc/net/r8180/
  proc: Add proc_mkdir_data()
  proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
  proc: Move PDE_NET() to fs/proc/proc_net.c
  ...
</content>
</entry>
<entry>
<title>take cgroup_open() and cpuset_open() to fs/proc/base.c</title>
<updated>2013-05-01T21:29:46Z</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2013-04-20T03:11:24Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=8d8b97ba499cb69fccb5fd9f2b439e3265fc3f27'/>
<id>urn:sha1:8d8b97ba499cb69fccb5fd9f2b439e3265fc3f27</id>
<content type='text'>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>cpuset: remove include of cgroup.h from cpuset.h</title>
<updated>2013-03-05T17:33:26Z</updated>
<author>
<name>Li Zefan</name>
<email>lizefan@huawei.com</email>
</author>
<published>2013-03-05T03:37:56Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=ff794dea52eaaa09017efea688a1d7f92ab0818e'/>
<id>urn:sha1:ff794dea52eaaa09017efea688a1d7f92ab0818e</id>
<content type='text'>
We don't need to include cgroup.h in cpuset.h.

Signed-off-by: Li Zefan &lt;lizefan@huawei.com&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
</content>
</entry>
<entry>
<title>cpuset: use N_MEMORY instead N_HIGH_MEMORY</title>
<updated>2012-12-13T01:38:32Z</updated>
<author>
<name>Lai Jiangshan</name>
<email>laijs@cn.fujitsu.com</email>
</author>
<published>2012-12-12T21:51:24Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=38d7bee9d24adf4c95676a3dc902827c72930ebb'/>
<id>urn:sha1:38d7bee9d24adf4c95676a3dc902827c72930ebb</id>
<content type='text'>
N_HIGH_MEMORY stands for the nodes that has normal or high memory.
N_MEMORY stands for the nodes that has any memory.

The code here need to handle with the nodes which have memory, we should
use N_MEMORY instead.

Signed-off-by: Lai Jiangshan &lt;laijs@cn.fujitsu.com&gt;
Acked-by: Hillf Danton &lt;dhillf@gmail.com&gt;
Signed-off-by: Wen Congyang &lt;wency@cn.fujitsu.com&gt;
Cc: Christoph Lameter &lt;cl@linux.com&gt;
Cc: Lin Feng &lt;linfeng@cn.fujitsu.com&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
</feed>
