<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/include/linux/sem.h, branch v2.6.33.1</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>ipc/sem.c: add a per-semaphore pending list</title>
<updated>2009-12-16T15:20:10+00:00</updated>
<author>
<name>Manfred Spraul</name>
<email>manfred@colorfullife.com</email>
</author>
<published>2009-12-16T00:47:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b97e820ffffbf49e94ed60c9c26f1a54bccae924'/>
<id>b97e820ffffbf49e94ed60c9c26f1a54bccae924</id>
<content type='text'>
Based on Nick's findings:

sysv sem has the concept of semaphore arrays that consist out of multiple
semaphores.  Atomic operations that affect multiple semaphores are
supported.

The patch is the first step for optimizing simple, single semaphore
operations: In addition to the global list of all pending operations, a
2nd, per-semaphore list with the simple operations is added.

Note: this patch does not make sense by itself, the new list is used
nowhere.

Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Cc: Nick Piggin &lt;npiggin@suse.de&gt;
Cc: Pierre Peiffer &lt;peifferp@gmail.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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Based on Nick's findings:

sysv sem has the concept of semaphore arrays that consist out of multiple
semaphores.  Atomic operations that affect multiple semaphores are
supported.

The patch is the first step for optimizing simple, single semaphore
operations: In addition to the global list of all pending operations, a
2nd, per-semaphore list with the simple operations is added.

Note: this patch does not make sense by itself, the new list is used
nowhere.

Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Cc: Nick Piggin &lt;npiggin@suse.de&gt;
Cc: Pierre Peiffer &lt;peifferp@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipc/sem.c: rewrite undo list locking</title>
<updated>2008-07-25T17:53:42+00:00</updated>
<author>
<name>Manfred Spraul</name>
<email>manfred@colorfullife.com</email>
</author>
<published>2008-07-25T08:48:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=380af1b33b3ff92df5cda96329b58f5d1b6b5a53'/>
<id>380af1b33b3ff92df5cda96329b58f5d1b6b5a53</id>
<content type='text'>
The attached patch:
- reverses the locking order of ulp-&gt;lock and sem_lock:
  Previously, it was first ulp-&gt;lock, then inside sem_lock.
  Now it's the other way around.
- converts the undo structure to rcu.

Benefits:
- With the old locking order, IPC_RMID could not kfree the undo structures.
  The stale entries remained in the linked lists and were released later.
- The patch fixes a a race in semtimedop(): if both IPC_RMID and a semget() that
  recreates exactly the same id happen between find_alloc_undo() and sem_lock,
  then semtimedop() would access already kfree'd memory.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Reviewed-by: Nadia Derbey &lt;Nadia.Derbey@bull.net&gt;
Cc: Pierre Peiffer &lt;peifferp@gmail.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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The attached patch:
- reverses the locking order of ulp-&gt;lock and sem_lock:
  Previously, it was first ulp-&gt;lock, then inside sem_lock.
  Now it's the other way around.
- converts the undo structure to rcu.

Benefits:
- With the old locking order, IPC_RMID could not kfree the undo structures.
  The stale entries remained in the linked lists and were released later.
- The patch fixes a a race in semtimedop(): if both IPC_RMID and a semget() that
  recreates exactly the same id happen between find_alloc_undo() and sem_lock,
  then semtimedop() would access already kfree'd memory.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Reviewed-by: Nadia Derbey &lt;Nadia.Derbey@bull.net&gt;
Cc: Pierre Peiffer &lt;peifferp@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipc/sem.c: convert sem_array.sem_pending to struct list_head</title>
<updated>2008-07-25T17:53:42+00:00</updated>
<author>
<name>Manfred Spraul</name>
<email>manfred@colorfullife.com</email>
</author>
<published>2008-07-25T08:48:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a1193f8ec091cd8fd309cc2982abe4499f6f2b4d'/>
<id>a1193f8ec091cd8fd309cc2982abe4499f6f2b4d</id>
<content type='text'>
sem_array.sem_pending is a double linked list, the attached patch converts
it to struct list_head.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Reviewed-by: Nadia Derbey &lt;Nadia.Derbey@bull.net&gt;
Cc: Pierre Peiffer &lt;peifferp@gmail.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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
sem_array.sem_pending is a double linked list, the attached patch converts
it to struct list_head.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Reviewed-by: Nadia Derbey &lt;Nadia.Derbey@bull.net&gt;
Cc: Pierre Peiffer &lt;peifferp@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipc/sem.c: remove unused entries from struct sem_queue</title>
<updated>2008-07-25T17:53:42+00:00</updated>
<author>
<name>Manfred Spraul</name>
<email>manfred@colorfullife.com</email>
</author>
<published>2008-07-25T08:48:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2c0c29d414087f3b021059673c20a7088f5f1fff'/>
<id>2c0c29d414087f3b021059673c20a7088f5f1fff</id>
<content type='text'>
sem_queue.sma and sem_queue.id were never used, the attached patch removes
them.

Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Reviewed-by: Nadia Derbey &lt;Nadia.Derbey@bull.net&gt;
Cc: Pierre Peiffer &lt;peifferp@gmail.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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
sem_queue.sma and sem_queue.id were never used, the attached patch removes
them.

Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Reviewed-by: Nadia Derbey &lt;Nadia.Derbey@bull.net&gt;
Cc: Pierre Peiffer &lt;peifferp@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipc/sem.c: convert undo structures to struct list_head</title>
<updated>2008-07-25T17:53:42+00:00</updated>
<author>
<name>Manfred Spraul</name>
<email>manfred@colorfullife.com</email>
</author>
<published>2008-07-25T08:48:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=4daa28f6d8f5cda8ea0f55048e3c8811c384cbdd'/>
<id>4daa28f6d8f5cda8ea0f55048e3c8811c384cbdd</id>
<content type='text'>
The undo structures contain two linked lists, the attached patch replaces
them with generic struct list_head lists.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Cc: Nadia Derbey &lt;Nadia.Derbey@bull.net&gt;
Cc: Pierre Peiffer &lt;peifferp@gmail.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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The undo structures contain two linked lists, the attached patch replaces
them with generic struct list_head lists.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Cc: Nadia Derbey &lt;Nadia.Derbey@bull.net&gt;
Cc: Pierre Peiffer &lt;peifferp@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipc: store ipcs into IDRs</title>
<updated>2007-10-19T18:53:44+00:00</updated>
<author>
<name>Nadia Derbey</name>
<email>Nadia.Derbey@bull.net</email>
</author>
<published>2007-10-19T06:40:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7ca7e564e049d8b350ec9d958ff25eaa24226352'/>
<id>7ca7e564e049d8b350ec9d958ff25eaa24226352</id>
<content type='text'>
This patch introduces ipcs storage into IDRs. The main changes are:
  . This ipc_ids structure is changed: the entries array is changed into a
    root idr structure.
  . The grow_ary() routine is removed: it is not needed anymore when adding
    an ipc structure, since we are now using the IDR facility.
  . The ipc_rmid() routine interface is changed:
       . there is no need for this routine to return the pointer passed in as
         argument: it is now declared as a void
       . since the id is now part of the kern_ipc_perm structure, no need to
         have it as an argument to the routine

Signed-off-by: Nadia Derbey &lt;Nadia.Derbey@bull.net&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch introduces ipcs storage into IDRs. The main changes are:
  . This ipc_ids structure is changed: the entries array is changed into a
    root idr structure.
  . The grow_ary() routine is removed: it is not needed anymore when adding
    an ipc structure, since we are now using the IDR facility.
  . The ipc_rmid() routine interface is changed:
       . there is no need for this routine to return the pointer passed in as
         argument: it is now declared as a void
       . since the id is now part of the kern_ipc_perm structure, no need to
         have it as an argument to the routine

Signed-off-by: Nadia Derbey &lt;Nadia.Derbey@bull.net&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Don't include &lt;asm/atomic.h&gt; from user-visible part of linux/sem.h</title>
<updated>2006-04-25T13:55:13+00:00</updated>
<author>
<name>David Woodhouse</name>
<email>dwmw2@infradead.org</email>
</author>
<published>2006-04-25T13:55:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8ffbc759a5b655feb69435c4dfa857c391f9dcc8'/>
<id>8ffbc759a5b655feb69435c4dfa857c391f9dcc8</id>
<content type='text'>
Signed-off-by: David Woodhouse &lt;dwmw2@infradead.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: David Woodhouse &lt;dwmw2@infradead.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>[PATCH] fix remaining missing includes</title>
<updated>2005-11-07T15:53:41+00:00</updated>
<author>
<name>Tim Schmielau</name>
<email>tim@physik3.uni-rostock.de</email>
</author>
<published>2005-11-07T08:59:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8c65b4a60450590e79a28e9717ceffa9e4debb3f'/>
<id>8c65b4a60450590e79a28e9717ceffa9e4debb3f</id>
<content type='text'>
Fix more include file problems that surfaced since I submitted the previous
fix-missing-includes.patch.  This should now allow not to include sched.h
from module.h, which is done by a followup patch.

Signed-off-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>
Fix more include file problems that surfaced since I submitted the previous
fix-missing-includes.patch.  This should now allow not to include sched.h
from module.h, which is done by a followup patch.

Signed-off-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] ipc: convert /proc/sysvipc/* to generic seq_file interface</title>
<updated>2005-09-07T23:57:26+00:00</updated>
<author>
<name>Mike Waychison</name>
<email>mikew@google.com</email>
</author>
<published>2005-09-06T22:17:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=19b4946ca9d1e35d4c641dcebe27378de34f3ddd'/>
<id>19b4946ca9d1e35d4c641dcebe27378de34f3ddd</id>
<content type='text'>
Change the /proc/sysvipc/shm|sem|msg files to use the generic seq_file
implementation for struct ipc_ids.

Signed-off-by: Mike Waychison &lt;mikew@google.com&gt;
Cc: Manfred Spraul &lt;manfred@colorfullife.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>
Change the /proc/sysvipc/shm|sem|msg files to use the generic seq_file
implementation for struct ipc_ids.

Signed-off-by: Mike Waychison &lt;mikew@google.com&gt;
Cc: Manfred Spraul &lt;manfred@colorfullife.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>Linux-2.6.12-rc2</title>
<updated>2005-04-16T22:20:36+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@ppc970.osdl.org</email>
</author>
<published>2005-04-16T22:20:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2'/>
<id>1da177e4c3f41524e886b7f1b8a0c1fc7321cac2</id>
<content type='text'>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
</pre>
</div>
</content>
</entry>
</feed>
