<feed xmlns='http://www.w3.org/2005/Atom'>
<title>lwn.git/fs/freevxfs/vxfs_inode.c, branch v4.6-rc2</title>
<subtitle>Linux kernel documentation tree maintained by Jonathan Corbet</subtitle>
<id>http://mirrors.hust.edu.cn/git/lwn.git/atom?h=v4.6-rc2</id>
<link rel='self' href='http://mirrors.hust.edu.cn/git/lwn.git/atom?h=v4.6-rc2'/>
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<updated>2015-12-09T03:41:36+00:00</updated>
<entry>
<title>don't put symlink bodies in pagecache into highmem</title>
<updated>2015-12-09T03:41:36+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2015-11-17T06:07:57+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=21fc61c73c3903c4c312d0802da01ec2b323d174'/>
<id>urn:sha1:21fc61c73c3903c4c312d0802da01ec2b323d174</id>
<content type='text'>
kmap() in page_follow_link_light() needed to go - allowing to hold
an arbitrary number of kmaps for long is a great way to deadlocking
the system.

new helper (inode_nohighmem(inode)) needs to be used for pagecache
symlinks inodes; done for all in-tree cases.  page_follow_link_light()
instrumented to yell about anything missed.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>freevxfs: switch to simple_follow_link()</title>
<updated>2015-05-11T02:18:27+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2015-05-02T14:43:25+00:00</published>
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<id>urn:sha1:df64c082efd1f71d27d942dbfc628877272e6809</id>
<content type='text'>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>mm + fs: store shadow entries in page cache</title>
<updated>2014-04-03T23:21:01+00:00</updated>
<author>
<name>Johannes Weiner</name>
<email>hannes@cmpxchg.org</email>
</author>
<published>2014-04-03T21:47:49+00:00</published>
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<id>urn:sha1:91b0abe36a7b2b3b02d7500925a5f8455334f0e5</id>
<content type='text'>
Reclaim will be leaving shadow entries in the page cache radix tree upon
evicting the real page.  As those pages are found from the LRU, an
iput() can lead to the inode being freed concurrently.  At this point,
reclaim must no longer install shadow pages because the inode freeing
code needs to ensure the page tree is really empty.

Add an address_space flag, AS_EXITING, that the inode freeing code sets
under the tree lock before doing the final truncate.  Reclaim will check
for this flag before installing shadow pages.

Signed-off-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Reviewed-by: Rik van Riel &lt;riel@redhat.com&gt;
Reviewed-by: Minchan Kim &lt;minchan@kernel.org&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Bob Liu &lt;bob.liu@oracle.com&gt;
Cc: Christoph Hellwig &lt;hch@infradead.org&gt;
Cc: Dave Chinner &lt;david@fromorbit.com&gt;
Cc: Greg Thelen &lt;gthelen@google.com&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Cc: Jan Kara &lt;jack@suse.cz&gt;
Cc: KOSAKI Motohiro &lt;kosaki.motohiro@jp.fujitsu.com&gt;
Cc: Luigi Semenzato &lt;semenzato@google.com&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Metin Doslu &lt;metin@citusdata.com&gt;
Cc: Michel Lespinasse &lt;walken@google.com&gt;
Cc: Ozgun Erdogan &lt;ozgun@citusdata.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Roman Gushchin &lt;klamm@yandex-team.ru&gt;
Cc: Ryan Mallon &lt;rmallon@gmail.com&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&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>userns: Convert freevxfs to use kuid/kgid where appropriate</title>
<updated>2012-09-21T10:13:19+00:00</updated>
<author>
<name>Eric W. Biederman</name>
<email>ebiederm@xmission.com</email>
</author>
<published>2012-02-10T19:26:34+00:00</published>
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<id>urn:sha1:2f83ffa874ccb6ea4596220188d3e54b20203124</id>
<content type='text'>
Cc: Christoph Hellwig &lt;hch@infradead.org&gt;
Acked-by: Serge Hallyn &lt;serge.hallyn@canonical.com&gt;
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
</content>
</entry>
<entry>
<title>vfs: Rename end_writeback() to clear_inode()</title>
<updated>2012-05-06T05:43:41+00:00</updated>
<author>
<name>Jan Kara</name>
<email>jack@suse.cz</email>
</author>
<published>2012-05-03T12:48:02+00:00</published>
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<id>urn:sha1:dbd5768f87ff6fb0a4fe09c4d7b6c4a24de99430</id>
<content type='text'>
After we moved inode_sync_wait() from end_writeback() it doesn't make sense
to call the function end_writeback() anymore. Rename it to clear_inode()
which well says what the function really does - set I_CLEAR flag.

Signed-off-by: Jan Kara &lt;jack@suse.cz&gt;
Signed-off-by: Fengguang Wu &lt;fengguang.wu@intel.com&gt;
</content>
</entry>
<entry>
<title>fs: propagate umode_t, misc bits</title>
<updated>2012-01-04T03:55:10+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2011-07-26T07:30:54+00:00</published>
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<id>urn:sha1:175a4eb7ea531cdbf6d574f5d5ba9aa0f5e8ed13</id>
<content type='text'>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>vfs: fix the stupidity with i_dentry in inode destructors</title>
<updated>2012-01-04T03:52:40+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2011-12-12T20:51:45+00:00</published>
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<id>urn:sha1:6b520e0565422966cdf1c3759bd73df77b0f248c</id>
<content type='text'>
Seeing that just about every destructor got that INIT_LIST_HEAD() copied into
it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once();
the cost of taking it into inode_init_always() will be negligible for pipes
and sockets and negative for everything else.  Not to mention the removal of
boilerplate code from -&gt;destroy_inode() instances...

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>filesystems: add set_nlink()</title>
<updated>2011-11-02T11:53:43+00:00</updated>
<author>
<name>Miklos Szeredi</name>
<email>mszeredi@suse.cz</email>
</author>
<published>2011-10-28T12:13:29+00:00</published>
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<id>urn:sha1:bfe8684869601dacfcb2cd69ef8cfd9045f62170</id>
<content type='text'>
Replace remaining direct i_nlink updates with a new set_nlink()
updater function.

Signed-off-by: Miklos Szeredi &lt;mszeredi@suse.cz&gt;
Tested-by: Toshiyuki Okajima &lt;toshi.okajima@jp.fujitsu.com&gt;
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
</content>
</entry>
<entry>
<title>treewide: fix a few typos in comments</title>
<updated>2011-05-10T08:16:21+00:00</updated>
<author>
<name>Justin P. Mattock</name>
<email>justinmattock@gmail.com</email>
</author>
<published>2011-05-10T08:16:21+00:00</published>
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<id>urn:sha1:70f23fd66bc821a0e99647f70a809e277cc93c4c</id>
<content type='text'>
- kenrel -&gt; kernel
- whetehr -&gt; whether
- ttt -&gt; tt
- sss -&gt; ss

Signed-off-by: Justin P. Mattock &lt;justinmattock@gmail.com&gt;
Signed-off-by: Jiri Kosina &lt;jkosina@suse.cz&gt;
</content>
</entry>
<entry>
<title>fs: icache RCU free inodes</title>
<updated>2011-01-07T06:50:26+00:00</updated>
<author>
<name>Nick Piggin</name>
<email>npiggin@kernel.dk</email>
</author>
<published>2011-01-07T06:49:49+00:00</published>
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<id>urn:sha1:fa0d7e3de6d6fc5004ad9dea0dd6b286af8f03e9</id>
<content type='text'>
RCU free the struct inode. This will allow:

- Subsequent store-free path walking patch. The inode must be consulted for
  permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
  to take i_lock no longer need to take sb_inode_list_lock to walk the list in
  the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
  page lock to follow page-&gt;mapping.

The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.

In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.

The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.

Signed-off-by: Nick Piggin &lt;npiggin@kernel.dk&gt;
</content>
</entry>
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