<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/fs/file_table.c, branch v2.6.18</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Remove obsolete #include &lt;linux/config.h&gt;</title>
<updated>2006-06-30T17:25:36+00:00</updated>
<author>
<name>Jörn Engel</name>
<email>joern@wohnheim.fh-wedel.de</email>
</author>
<published>2006-06-30T17:25:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6ab3d5624e172c553004ecc862bfeac16d9d68b7'/>
<id>6ab3d5624e172c553004ecc862bfeac16d9d68b7</id>
<content type='text'>
Signed-off-by: Jörn Engel &lt;joern@wohnheim.fh-wedel.de&gt;
Signed-off-by: Adrian Bunk &lt;bunk@stusta.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Jörn Engel &lt;joern@wohnheim.fh-wedel.de&gt;
Signed-off-by: Adrian Bunk &lt;bunk@stusta.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>[PATCH] percpu counter data type changes to suppport more than 2**31 ext3 free blocks counter</title>
<updated>2006-06-23T14:43:06+00:00</updated>
<author>
<name>Mingming Cao</name>
<email>cmm@us.ibm.com</email>
</author>
<published>2006-06-23T09:05:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0216bfcffe424a5473daa4da47440881b36c1f41'/>
<id>0216bfcffe424a5473daa4da47440881b36c1f41</id>
<content type='text'>
The percpu counter data type are changed in this set of patches to support
more users like ext3 who need more than 32 bit to store the free blocks
total in the filesystem.

- Generic perpcu counters data type changes.  The size of the global counter
  and local counter were explictly specified using s64 and s32.  The global
  counter is changed from long to s64, while the local counter is changed from
  long to s32, so we could avoid doing 64 bit update in most cases.

- Users of the percpu counters are updated to make use of the new
  percpu_counter_init() routine now taking an additional parameter to allow
  users to pass the initial value of the global counter.

Signed-off-by: Mingming Cao &lt;cmm@us.ibm.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 percpu counter data type are changed in this set of patches to support
more users like ext3 who need more than 32 bit to store the free blocks
total in the filesystem.

- Generic perpcu counters data type changes.  The size of the global counter
  and local counter were explictly specified using s64 and s32.  The global
  counter is changed from long to s64, while the local counter is changed from
  long to s32, so we could avoid doing 64 bit update in most cases.

- Users of the percpu counters are updated to make use of the new
  percpu_counter_init() routine now taking an additional parameter to allow
  users to pass the initial value of the global counter.

Signed-off-by: Mingming Cao &lt;cmm@us.ibm.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>
<entry>
<title>[PATCH] get_empty_filp tweaks, inline epoll_init_file()</title>
<updated>2006-03-23T15:38:17+00:00</updated>
<author>
<name>Benjamin LaHaise</name>
<email>bcrl@linux.intel.com</email>
</author>
<published>2006-03-23T11:01:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5a6b7951bfcca7f45f44269ea87417c74558daf8'/>
<id>5a6b7951bfcca7f45f44269ea87417c74558daf8</id>
<content type='text'>
Eliminate a handful of cache references by keeping current in a register
instead of reloading (helps x86) and avoiding the overhead of a function
call.  Inlining eventpoll_init_file() saves 24 bytes.  Also reorder file
initialization to make writes occur more sequentially.

Signed-off-by: Benjamin LaHaise &lt;bcrl@linux.intel.com&gt;
Cc: Davide Libenzi &lt;davidel@xmailserver.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>
Eliminate a handful of cache references by keeping current in a register
instead of reloading (helps x86) and avoiding the overhead of a function
call.  Inlining eventpoll_init_file() saves 24 bytes.  Also reorder file
initialization to make writes occur more sequentially.

Signed-off-by: Benjamin LaHaise &lt;bcrl@linux.intel.com&gt;
Cc: Davide Libenzi &lt;davidel@xmailserver.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>[PATCH] fix file counting</title>
<updated>2006-03-08T22:14:01+00:00</updated>
<author>
<name>Dipankar Sarma</name>
<email>dipankar@in.ibm.com</email>
</author>
<published>2006-03-08T05:55:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=529bf6be5c04f2e869d07bfdb122e9fd98ade714'/>
<id>529bf6be5c04f2e869d07bfdb122e9fd98ade714</id>
<content type='text'>
I have benchmarked this on an x86_64 NUMA system and see no significant
performance difference on kernbench.  Tested on both x86_64 and powerpc.

The way we do file struct accounting is not very suitable for batched
freeing.  For scalability reasons, file accounting was
constructor/destructor based.  This meant that nr_files was decremented
only when the object was removed from the slab cache.  This is susceptible
to slab fragmentation.  With RCU based file structure, consequent batched
freeing and a test program like Serge's, we just speed this up and end up
with a very fragmented slab -

llm22:~ # cat /proc/sys/fs/file-nr
587730  0       758844

At the same time, I see only a 2000+ objects in filp cache.  The following
patch I fixes this problem.

This patch changes the file counting by removing the filp_count_lock.
Instead we use a separate percpu counter, nr_files, for now and all
accesses to it are through get_nr_files() api.  In the sysctl handler for
nr_files, we populate files_stat.nr_files before returning to user.

Counting files as an when they are created and destroyed (as opposed to
inside slab) allows us to correctly count open files with RCU.

Signed-off-by: Dipankar Sarma &lt;dipankar@in.ibm.com&gt;
Cc: "Paul E. McKenney" &lt;paulmck@us.ibm.com&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&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>
I have benchmarked this on an x86_64 NUMA system and see no significant
performance difference on kernbench.  Tested on both x86_64 and powerpc.

The way we do file struct accounting is not very suitable for batched
freeing.  For scalability reasons, file accounting was
constructor/destructor based.  This meant that nr_files was decremented
only when the object was removed from the slab cache.  This is susceptible
to slab fragmentation.  With RCU based file structure, consequent batched
freeing and a test program like Serge's, we just speed this up and end up
with a very fragmented slab -

llm22:~ # cat /proc/sys/fs/file-nr
587730  0       758844

At the same time, I see only a 2000+ objects in filp cache.  The following
patch I fixes this problem.

This patch changes the file counting by removing the filp_count_lock.
Instead we use a separate percpu counter, nr_files, for now and all
accesses to it are through get_nr_files() api.  In the sysctl handler for
nr_files, we populate files_stat.nr_files before returning to user.

Counting files as an when they are created and destroyed (as opposed to
inside slab) allows us to correctly count open files with RCU.

Signed-off-by: Dipankar Sarma &lt;dipankar@in.ibm.com&gt;
Cc: "Paul E. McKenney" &lt;paulmck@us.ibm.com&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&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] capable/capability.h (fs/)</title>
<updated>2006-01-12T02:42:13+00:00</updated>
<author>
<name>Randy Dunlap</name>
<email>rdunlap@xenotime.net</email>
</author>
<published>2006-01-11T20:17:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=16f7e0fe2ecc30f30652e8185e1772cdebe39109'/>
<id>16f7e0fe2ecc30f30652e8185e1772cdebe39109</id>
<content type='text'>
fs: Use &lt;linux/capability.h&gt; where capable() is used.

Signed-off-by: Randy Dunlap &lt;rdunlap@xenotime.net&gt;
Acked-by: Tim Schmielau &lt;tim@physik3.uni-rostock.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>
fs: Use &lt;linux/capability.h&gt; where capable() is used.

Signed-off-by: Randy Dunlap &lt;rdunlap@xenotime.net&gt;
Acked-by: Tim Schmielau &lt;tim@physik3.uni-rostock.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] rcu file: use atomic primitives</title>
<updated>2006-01-09T04:13:48+00:00</updated>
<author>
<name>Nick Piggin</name>
<email>nickpiggin@yahoo.com.au</email>
</author>
<published>2006-01-08T09:02:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=095975da26dba21698582e91e96be10f7417333f'/>
<id>095975da26dba21698582e91e96be10f7417333f</id>
<content type='text'>
Use atomic_inc_not_zero for rcu files instead of special case rcuref.

Signed-off-by: Nick Piggin &lt;npiggin@suse.de&gt;
Cc: "Paul E. McKenney" &lt;paulmck@us.ibm.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>
Use atomic_inc_not_zero for rcu files instead of special case rcuref.

Signed-off-by: Nick Piggin &lt;npiggin@suse.de&gt;
Cc: "Paul E. McKenney" &lt;paulmck@us.ibm.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>
<entry>
<title>[PATCH] mm: rename kmem_cache_s to kmem_cache</title>
<updated>2005-11-07T15:53:24+00:00</updated>
<author>
<name>Pekka J Enberg</name>
<email>penberg@cs.Helsinki.FI</email>
</author>
<published>2005-11-07T08:58:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2109a2d1b175dfcffbfdac693bdbe4c4ab62f11f'/>
<id>2109a2d1b175dfcffbfdac693bdbe4c4ab62f11f</id>
<content type='text'>
This patch renames struct kmem_cache_s to kmem_cache so we can start using
it instead of kmem_cache_t typedef.

Signed-off-by: Pekka Enberg &lt;penberg@cs.helsinki.fi&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>
This patch renames struct kmem_cache_s to kmem_cache so we can start using
it instead of kmem_cache_t typedef.

Signed-off-by: Pekka Enberg &lt;penberg@cs.helsinki.fi&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] reduce sizeof(struct file)</title>
<updated>2005-10-31T01:37:19+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>dada1@cosmosbay.com</email>
</author>
<published>2005-10-30T23:02:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2f51201662b28dbf8c15fb7eb972bc51c6cc3fa5'/>
<id>2f51201662b28dbf8c15fb7eb972bc51c6cc3fa5</id>
<content type='text'>
Now that RCU applied on 'struct file' seems stable, we can place f_rcuhead
in a memory location that is not anymore used at call_rcu(&amp;f-&gt;f_rcuhead,
file_free_rcu) time, to reduce the size of this critical kernel object.

The trick I used is to move f_rcuhead and f_list in an union called f_u

The callers are changed so that f_rcuhead becomes f_u.fu_rcuhead and f_list
becomes f_u.f_list

Signed-off-by: Eric Dumazet &lt;dada1@cosmosbay.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>
Now that RCU applied on 'struct file' seems stable, we can place f_rcuhead
in a memory location that is not anymore used at call_rcu(&amp;f-&gt;f_rcuhead,
file_free_rcu) time, to reduce the size of this critical kernel object.

The trick I used is to move f_rcuhead and f_list in an union called f_u

The callers are changed so that f_rcuhead becomes f_u.fu_rcuhead and f_list
becomes f_u.f_list

Signed-off-by: Eric Dumazet &lt;dada1@cosmosbay.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>
<entry>
<title>[PATCH] files: files struct with RCU</title>
<updated>2005-09-09T20:57:55+00:00</updated>
<author>
<name>Dipankar Sarma</name>
<email>dipankar@in.ibm.com</email>
</author>
<published>2005-09-09T20:04:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ab2af1f5005069321c5d130f09cce577b03f43ef'/>
<id>ab2af1f5005069321c5d130f09cce577b03f43ef</id>
<content type='text'>
Patch to eliminate struct files_struct.file_lock spinlock on the reader side
and use rcu refcounting rcuref_xxx api for the f_count refcounter.  The
updates to the fdtable are done by allocating a new fdtable structure and
setting files-&gt;fdt to point to the new structure.  The fdtable structure is
protected by RCU thereby allowing lock-free lookup.  For fd arrays/sets that
are vmalloced, we use keventd to free them since RCU callbacks can't sleep.  A
global list of fdtable to be freed is not scalable, so we use a per-cpu list.
If keventd is already handling the current cpu's work, we use a timer to defer
queueing of that work.

Since the last publication, this patch has been re-written to avoid using
explicit memory barriers and use rcu_assign_pointer(), rcu_dereference()
premitives instead.  This required that the fd information is kept in a
separate structure (fdtable) and updated atomically.

Signed-off-by: Dipankar Sarma &lt;dipankar@in.ibm.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>
Patch to eliminate struct files_struct.file_lock spinlock on the reader side
and use rcu refcounting rcuref_xxx api for the f_count refcounter.  The
updates to the fdtable are done by allocating a new fdtable structure and
setting files-&gt;fdt to point to the new structure.  The fdtable structure is
protected by RCU thereby allowing lock-free lookup.  For fd arrays/sets that
are vmalloced, we use keventd to free them since RCU callbacks can't sleep.  A
global list of fdtable to be freed is not scalable, so we use a per-cpu list.
If keventd is already handling the current cpu's work, we use a timer to defer
queueing of that work.

Since the last publication, this patch has been re-written to avoid using
explicit memory barriers and use rcu_assign_pointer(), rcu_dereference()
premitives instead.  This required that the fd information is kept in a
separate structure (fdtable) and updated atomically.

Signed-off-by: Dipankar Sarma &lt;dipankar@in.ibm.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>
<entry>
<title>[PATCH] remove file.f_maxcount</title>
<updated>2005-09-07T23:57:32+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>dada1@cosmosbay.com</email>
</author>
<published>2005-09-06T22:17:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2832e9366a1fcd6f76957a42157be041240f994e'/>
<id>2832e9366a1fcd6f76957a42157be041240f994e</id>
<content type='text'>
struct file cleanup: f_maxcount has an unique value (INT_MAX).  Just use
the hard-wired value.

Signed-off-by: Eric Dumazet &lt;dada1@cosmosbay.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>
struct file cleanup: f_maxcount has an unique value (INT_MAX).  Just use
the hard-wired value.

Signed-off-by: Eric Dumazet &lt;dada1@cosmosbay.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>
