<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/fs/inode.c, branch v2.6.19.2</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>[PATCH] Take i_mutex in splice_from_pipe()</title>
<updated>2006-10-19T18:53:08+00:00</updated>
<author>
<name>Mark Fasheh</name>
<email>mark.fasheh@oracle.com</email>
</author>
<published>2006-10-17T08:31:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=62752ee198dca9209b7dee504763e51b11e9e0ca'/>
<id>62752ee198dca9209b7dee504763e51b11e9e0ca</id>
<content type='text'>
The splice_actor may be calling -&gt;prepare_write() and -&gt;commit_write(). We
want i_mutex on the inode being written to before calling those so that we
don't race i_size changes.

The double locking behavior is done elsewhere in splice.c, and if we
eventually want _nolock variants of generic_file_splice_write(), fs modules
might have to replicate the nasty locking code. We introduce
inode_double_lock() and inode_double_unlock() to consolidate the locking
rules into one set of functions.

Signed-off-by: Mark Fasheh &lt;mark.fasheh@oracle.com&gt;
Signed-off-by: Jens Axboe &lt;jens.axboe@oracle.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The splice_actor may be calling -&gt;prepare_write() and -&gt;commit_write(). We
want i_mutex on the inode being written to before calling those so that we
don't race i_size changes.

The double locking behavior is done elsewhere in splice.c, and if we
eventually want _nolock variants of generic_file_splice_write(), fs modules
might have to replicate the nasty locking code. We introduce
inode_double_lock() and inode_double_unlock() to consolidate the locking
rules into one set of functions.

Signed-off-by: Mark Fasheh &lt;mark.fasheh@oracle.com&gt;
Signed-off-by: Jens Axboe &lt;jens.axboe@oracle.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>[PATCH] fs/inode.c NULL noise removal</title>
<updated>2006-10-10T22:37:23+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@ftp.linux.org.uk</email>
</author>
<published>2006-10-10T21:48:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e6c6e640b8b258dc7f60533e81f050d15fc0a9af'/>
<id>e6c6e640b8b258dc7f60533e81f050d15fc0a9af</id>
<content type='text'>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>[PATCH] fs/inode.c tweaks</title>
<updated>2006-10-02T14:57:14+00:00</updated>
<author>
<name>Andreas Mohr</name>
<email>andi@rhlx01.fht-esslingen.de</email>
</author>
<published>2006-10-02T09:17:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ed97bd37efd8ff7398d3a7eedf4bcbf245f5dad3'/>
<id>ed97bd37efd8ff7398d3a7eedf4bcbf245f5dad3</id>
<content type='text'>
Only touch inode's i_mtime and i_ctime to make them equal to "now" in case
they aren't yet (don't just update timestamp unconditionally).  Uninline
the hash function to save 259 Bytes.

This tiny inode change which may improve cache behaviour also shaves off 8
Bytes from file_update_time() on i386.

Included a tiny codestyle cleanup, too.

Signed-off-by: Andreas Mohr &lt;andi@lisas.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@osdl.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Only touch inode's i_mtime and i_ctime to make them equal to "now" in case
they aren't yet (don't just update timestamp unconditionally).  Uninline
the hash function to save 259 Bytes.

This tiny inode change which may improve cache behaviour also shaves off 8
Bytes from file_update_time() on i386.

Included a tiny codestyle cleanup, too.

Signed-off-by: Andreas Mohr &lt;andi@lisas.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@osdl.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>[PATCH] BLOCK: Move __invalidate_device() to block_dev.c [try #6]</title>
<updated>2006-09-30T18:52:27+00:00</updated>
<author>
<name>David Howells</name>
<email>dhowells@redhat.com</email>
</author>
<published>2006-08-29T18:06:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b71e8a4ce03b3098c7801ee5e6e08d1a39a226c2'/>
<id>b71e8a4ce03b3098c7801ee5e6e08d1a39a226c2</id>
<content type='text'>
Move __invalidate_device() from fs/inode.c to fs/block_dev.c so that it can
more easily be disabled when the block layer is disabled.

Signed-Off-By: David Howells &lt;dhowells@redhat.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Move __invalidate_device() from fs/inode.c to fs/block_dev.c so that it can
more easily be disabled when the block layer is disabled.

Signed-Off-By: David Howells &lt;dhowells@redhat.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>[PATCH] fs.h: ifdef security fields</title>
<updated>2006-09-29T16:18:11+00:00</updated>
<author>
<name>Alexey Dobriyan</name>
<email>adobriyan@gmail.com</email>
</author>
<published>2006-09-29T09:00:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=50462062a02226a698a211d5bd535376c89b8603'/>
<id>50462062a02226a698a211d5bd535376c89b8603</id>
<content type='text'>
[assuming BSD security levels are deleted]
The only user of i_security, f_security, s_security fields is SELinux,
however, quite a few security modules are trying to get into kernel.
So, wrap them under CONFIG_SECURITY. Adding config option for each
security field is likely an overkill.

Following Stephen Smalley's suggestion, i_security initialization is
moved to security_inode_alloc() to not clutter core code with ifdefs
and make alloc_inode() codepath tiny little bit smaller and faster.

The user of (highly greppable) struct fown_struct::security field is
still to be found. I've checked every "fown_struct" and every "f_owner"
occurence. Additionally it's removal doesn't break i386 allmodconfig
build.

struct inode, struct file, struct super_block, struct fown_struct
become smaller.

P.S. Combined with two reiserfs inode shrinking patches sent to
linux-fsdevel, I can finally suck 12 reiserfs inodes into one page.

		/proc/slabinfo

	-ext2_inode_cache	388	10
	+ext2_inode_cache	384	10
	-inode_cache		280	14
	+inode_cache		276	14
	-proc_inode_cache	296	13
	+proc_inode_cache	292	13
	-reiser_inode_cache	336	11
	+reiser_inode_cache	332	12 &lt;=
	-shmem_inode_cache	372	10
	+shmem_inode_cache	368	10

Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Cc: Stephen Smalley &lt;sds@tycho.nsa.gov&gt;
Signed-off-by: Andrew Morton &lt;akpm@osdl.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[assuming BSD security levels are deleted]
The only user of i_security, f_security, s_security fields is SELinux,
however, quite a few security modules are trying to get into kernel.
So, wrap them under CONFIG_SECURITY. Adding config option for each
security field is likely an overkill.

Following Stephen Smalley's suggestion, i_security initialization is
moved to security_inode_alloc() to not clutter core code with ifdefs
and make alloc_inode() codepath tiny little bit smaller and faster.

The user of (highly greppable) struct fown_struct::security field is
still to be found. I've checked every "fown_struct" and every "f_owner"
occurence. Additionally it's removal doesn't break i386 allmodconfig
build.

struct inode, struct file, struct super_block, struct fown_struct
become smaller.

P.S. Combined with two reiserfs inode shrinking patches sent to
linux-fsdevel, I can finally suck 12 reiserfs inodes into one page.

		/proc/slabinfo

	-ext2_inode_cache	388	10
	+ext2_inode_cache	384	10
	-inode_cache		280	14
	+inode_cache		276	14
	-proc_inode_cache	296	13
	+proc_inode_cache	292	13
	-reiser_inode_cache	336	11
	+reiser_inode_cache	332	12 &lt;=
	-shmem_inode_cache	372	10
	+shmem_inode_cache	368	10

Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Cc: Stephen Smalley &lt;sds@tycho.nsa.gov&gt;
Signed-off-by: Andrew Morton &lt;akpm@osdl.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>[PATCH] inode-diet: Move i_cdev into a union</title>
<updated>2006-09-27T15:26:17+00:00</updated>
<author>
<name>Theodore Ts'o</name>
<email>tytso@mit.edu</email>
</author>
<published>2006-09-27T08:50:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=577c4eb09d1034d0739e3135fd2cff50588024be'/>
<id>577c4eb09d1034d0739e3135fd2cff50588024be</id>
<content type='text'>
Move the i_cdev pointer in struct inode into a union.

Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
Signed-off-by: Andrew Morton &lt;akpm@osdl.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Move the i_cdev pointer in struct inode into a union.

Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
Signed-off-by: Andrew Morton &lt;akpm@osdl.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>[PATCH] inode-diet: Move i_bdev into a union</title>
<updated>2006-09-27T15:26:17+00:00</updated>
<author>
<name>Theodore Ts'o</name>
<email>tytso@mit.edu</email>
</author>
<published>2006-09-27T08:50:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=eaf796e7ef6014f208c409b2b14fddcfaafe7e3a'/>
<id>eaf796e7ef6014f208c409b2b14fddcfaafe7e3a</id>
<content type='text'>
Move the i_bdev pointer in struct inode into a union.

Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
Signed-off-by: Andrew Morton &lt;akpm@osdl.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Move the i_bdev pointer in struct inode into a union.

Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
Signed-off-by: Andrew Morton &lt;akpm@osdl.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>[PATCH] inode_diet: Replace inode.u.generic_ip with inode.i_private</title>
<updated>2006-09-27T15:26:17+00:00</updated>
<author>
<name>Theodore Ts'o</name>
<email>tytso@mit.edu</email>
</author>
<published>2006-09-27T08:50:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8e18e2941c53416aa219708e7dcad21fb4bd6794'/>
<id>8e18e2941c53416aa219708e7dcad21fb4bd6794</id>
<content type='text'>
The following patches reduce the size of the VFS inode structure by 28 bytes
on a UP x86.  (It would be more on an x86_64 system).  This is a 10% reduction
in the inode size on a UP kernel that is configured in a production mode
(i.e., with no spinlock or other debugging functions enabled; if you want to
save memory taken up by in-core inodes, the first thing you should do is
disable the debugging options; they are responsible for a huge amount of bloat
in the VFS inode structure).

This patch:

The filesystem or device-specific pointer in the inode is inside a union,
which is pretty pointless given that all 30+ users of this field have been
using the void pointer.  Get rid of the union and rename it to i_private, with
a comment to explain who is allowed to use the void pointer.  This is just a
cleanup, but it allows us to reuse the union 'u' for something something where
the union will actually be used.

[judith@osdl.org: powerpc build fix]
Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
Signed-off-by: Judith Lebzelter &lt;judith@osdl.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@osdl.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The following patches reduce the size of the VFS inode structure by 28 bytes
on a UP x86.  (It would be more on an x86_64 system).  This is a 10% reduction
in the inode size on a UP kernel that is configured in a production mode
(i.e., with no spinlock or other debugging functions enabled; if you want to
save memory taken up by in-core inodes, the first thing you should do is
disable the debugging options; they are responsible for a huge amount of bloat
in the VFS inode structure).

This patch:

The filesystem or device-specific pointer in the inode is inside a union,
which is pretty pointless given that all 30+ users of this field have been
using the void pointer.  Get rid of the union and rename it to i_private, with
a comment to explain who is allowed to use the void pointer.  This is just a
cleanup, but it allows us to reuse the union 'u' for something something where
the union will actually be used.

[judith@osdl.org: powerpc build fix]
Signed-off-by: "Theodore Ts'o" &lt;tytso@mit.edu&gt;
Signed-off-by: Judith Lebzelter &lt;judith@osdl.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@osdl.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial</title>
<updated>2006-06-30T22:39:30+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@g5.osdl.org</email>
</author>
<published>2006-06-30T22:39:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=22a3e233ca08a2ddc949ba1ae8f6e16ec7ef1a13'/>
<id>22a3e233ca08a2ddc949ba1ae8f6e16ec7ef1a13</id>
<content type='text'>
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial:
  Remove obsolete #include &lt;linux/config.h&gt;
  remove obsolete swsusp_encrypt
  arch/arm26/Kconfig typos
  Documentation/IPMI typos
  Kconfig: Typos in net/sched/Kconfig
  v9fs: do not include linux/version.h
  Documentation/DocBook/mtdnand.tmpl: typo fixes
  typo fixes: specfic -&gt; specific
  typo fixes in Documentation/networking/pktgen.txt
  typo fixes: occuring -&gt; occurring
  typo fixes: infomation -&gt; information
  typo fixes: disadvantadge -&gt; disadvantage
  typo fixes: aquire -&gt; acquire
  typo fixes: mecanism -&gt; mechanism
  typo fixes: bandwith -&gt; bandwidth
  fix a typo in the RTC_CLASS help text
  smb is no longer maintained

Manually merged trivial conflict in arch/um/kernel/vmlinux.lds.S
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial:
  Remove obsolete #include &lt;linux/config.h&gt;
  remove obsolete swsusp_encrypt
  arch/arm26/Kconfig typos
  Documentation/IPMI typos
  Kconfig: Typos in net/sched/Kconfig
  v9fs: do not include linux/version.h
  Documentation/DocBook/mtdnand.tmpl: typo fixes
  typo fixes: specfic -&gt; specific
  typo fixes in Documentation/networking/pktgen.txt
  typo fixes: occuring -&gt; occurring
  typo fixes: infomation -&gt; information
  typo fixes: disadvantadge -&gt; disadvantage
  typo fixes: aquire -&gt; acquire
  typo fixes: mecanism -&gt; mechanism
  typo fixes: bandwith -&gt; bandwidth
  fix a typo in the RTC_CLASS help text
  smb is no longer maintained

Manually merged trivial conflict in arch/um/kernel/vmlinux.lds.S
</pre>
</div>
</content>
</entry>
<entry>
<title>[PATCH] Light weight event counters</title>
<updated>2006-06-30T18:25:36+00:00</updated>
<author>
<name>Christoph Lameter</name>
<email>clameter@sgi.com</email>
</author>
<published>2006-06-30T08:55:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f8891e5e1f93a128c3900f82035e8541357896a7'/>
<id>f8891e5e1f93a128c3900f82035e8541357896a7</id>
<content type='text'>
The remaining counters in page_state after the zoned VM counter patches
have been applied are all just for show in /proc/vmstat.  They have no
essential function for the VM.

We use a simple increment of per cpu variables.  In order to avoid the most
severe races we disable preempt.  Preempt does not prevent the race between
an increment and an interrupt handler incrementing the same statistics
counter.  However, that race is exceedingly rare, we may only loose one
increment or so and there is no requirement (at least not in kernel) that
the vm event counters have to be accurate.

In the non preempt case this results in a simple increment for each
counter.  For many architectures this will be reduced by the compiler to a
single instruction.  This single instruction is atomic for i386 and x86_64.
 And therefore even the rare race condition in an interrupt is avoided for
both architectures in most cases.

The patchset also adds an off switch for embedded systems that allows a
building of linux kernels without these counters.

The implementation of these counters is through inline code that hopefully
results in only a single instruction increment instruction being emitted
(i386, x86_64) or in the increment being hidden though instruction
concurrency (EPIC architectures such as ia64 can get that done).

Benefits:
- VM event counter operations usually reduce to a single inline instruction
  on i386 and x86_64.
- No interrupt disable, only preempt disable for the preempt case.
  Preempt disable can also be avoided by moving the counter into a spinlock.
- Handling is similar to zoned VM counters.
- Simple and easily extendable.
- Can be omitted to reduce memory use for embedded use.

References:

RFC http://marc.theaimsgroup.com/?l=linux-kernel&amp;m=113512330605497&amp;w=2
RFC http://marc.theaimsgroup.com/?l=linux-kernel&amp;m=114988082814934&amp;w=2
local_t http://marc.theaimsgroup.com/?l=linux-kernel&amp;m=114991748606690&amp;w=2
V2 http://marc.theaimsgroup.com/?t=115014808400007&amp;r=1&amp;w=2
V3 http://marc.theaimsgroup.com/?l=linux-kernel&amp;m=115024767022346&amp;w=2
V4 http://marc.theaimsgroup.com/?l=linux-kernel&amp;m=115047968808926&amp;w=2

Signed-off-by: Christoph Lameter &lt;clameter@sgi.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@osdl.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The remaining counters in page_state after the zoned VM counter patches
have been applied are all just for show in /proc/vmstat.  They have no
essential function for the VM.

We use a simple increment of per cpu variables.  In order to avoid the most
severe races we disable preempt.  Preempt does not prevent the race between
an increment and an interrupt handler incrementing the same statistics
counter.  However, that race is exceedingly rare, we may only loose one
increment or so and there is no requirement (at least not in kernel) that
the vm event counters have to be accurate.

In the non preempt case this results in a simple increment for each
counter.  For many architectures this will be reduced by the compiler to a
single instruction.  This single instruction is atomic for i386 and x86_64.
 And therefore even the rare race condition in an interrupt is avoided for
both architectures in most cases.

The patchset also adds an off switch for embedded systems that allows a
building of linux kernels without these counters.

The implementation of these counters is through inline code that hopefully
results in only a single instruction increment instruction being emitted
(i386, x86_64) or in the increment being hidden though instruction
concurrency (EPIC architectures such as ia64 can get that done).

Benefits:
- VM event counter operations usually reduce to a single inline instruction
  on i386 and x86_64.
- No interrupt disable, only preempt disable for the preempt case.
  Preempt disable can also be avoided by moving the counter into a spinlock.
- Handling is similar to zoned VM counters.
- Simple and easily extendable.
- Can be omitted to reduce memory use for embedded use.

References:

RFC http://marc.theaimsgroup.com/?l=linux-kernel&amp;m=113512330605497&amp;w=2
RFC http://marc.theaimsgroup.com/?l=linux-kernel&amp;m=114988082814934&amp;w=2
local_t http://marc.theaimsgroup.com/?l=linux-kernel&amp;m=114991748606690&amp;w=2
V2 http://marc.theaimsgroup.com/?t=115014808400007&amp;r=1&amp;w=2
V3 http://marc.theaimsgroup.com/?l=linux-kernel&amp;m=115024767022346&amp;w=2
V4 http://marc.theaimsgroup.com/?l=linux-kernel&amp;m=115047968808926&amp;w=2

Signed-off-by: Christoph Lameter &lt;clameter@sgi.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@osdl.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@osdl.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
