linux-toradex.git/Documentation/RCU, branch v2.6.32.31 Linux kernel for Apalis and Colibri modules rcu: Remove CONFIG_PREEMPT_RCU 2009-08-23T08:32:40+00:00 Paul E. McKenney paulmck@linux.vnet.ibm.com 2009-08-22T20:56:53+00:00 6b3ef48adf847f7adf11c870e3ffacac150f1564 Now that CONFIG_TREE_PREEMPT_RCU is in place, there is no further need for CONFIG_PREEMPT_RCU. Remove it, along with whatever subtle bugs it may (or may not) contain. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: akpm@linux-foundation.org Cc: mathieu.desnoyers@polymtl.ca Cc: josht@linux.vnet.ibm.com Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org LKML-Reference: <125097461396-git-send-email-> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Now that CONFIG_TREE_PREEMPT_RCU is in place, there is no
further need for CONFIG_PREEMPT_RCU.  Remove it, along with
whatever subtle bugs it may (or may not) contain.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <125097461396-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
rcu: Renamings to increase RCU clarity 2009-08-23T08:32:37+00:00 Paul E. McKenney paulmck@linux.vnet.ibm.com 2009-08-22T20:56:46+00:00 d6714c22b43fbcbead7e7b706ff270e15f04a791 Make RCU-sched, RCU-bh, and RCU-preempt be underlying implementations, with "RCU" defined in terms of one of the three. Update the outdated rcu_qsctr_inc() names, as these functions no longer increment anything. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: akpm@linux-foundation.org Cc: mathieu.desnoyers@polymtl.ca Cc: josht@linux.vnet.ibm.com Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org LKML-Reference: <12509746132696-git-send-email-> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Make RCU-sched, RCU-bh, and RCU-preempt be underlying
implementations, with "RCU" defined in terms of one of the
three.  Update the outdated rcu_qsctr_inc() names, as these
functions no longer increment anything.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12509746132696-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge commit 'v2.6.31-rc6' into core/rcu 2009-08-15T16:56:13+00:00 Ingo Molnar mingo@elte.hu 2009-08-15T16:55:58+00:00 fa08661af834875c9bd6f7f0b1b9388dc72a6585 Merge reason: the branch was on pre-rc1 .30, update to latest. Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Merge reason: the branch was on pre-rc1 .30, update to latest.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
netfilter: nf_conntrack: nf_conntrack_alloc() fixes 2009-07-16T12:03:40+00:00 Eric Dumazet eric.dumazet@gmail.com 2009-07-16T12:03:40+00:00 941297f443f871b8c3372feccf27a8733f6ce9e9 When a slab cache uses SLAB_DESTROY_BY_RCU, we must be careful when allocating objects, since slab allocator could give a freed object still used by lockless readers. In particular, nf_conntrack RCU lookups rely on ct->tuplehash[xxx].hnnode.next being always valid (ie containing a valid 'nulls' value, or a valid pointer to next object in hash chain.) kmem_cache_zalloc() setups object with NULL values, but a NULL value is not valid for ct->tuplehash[xxx].hnnode.next. Fix is to call kmem_cache_alloc() and do the zeroing ourself. As spotted by Patrick, we also need to make sure lookup keys are committed to memory before setting refcount to 1, or a lockless reader could get a reference on the old version of the object. Its key re-check could then pass the barrier. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Patrick McHardy <kaber@trash.net> 
When a slab cache uses SLAB_DESTROY_BY_RCU, we must be careful when allocating
objects, since slab allocator could give a freed object still used by lockless
readers.

In particular, nf_conntrack RCU lookups rely on ct->tuplehash[xxx].hnnode.next
being always valid (ie containing a valid 'nulls' value, or a valid pointer to next
object in hash chain.)

kmem_cache_zalloc() setups object with NULL values, but a NULL value is not valid
for ct->tuplehash[xxx].hnnode.next.

Fix is to call kmem_cache_alloc() and do the zeroing ourself.

As spotted by Patrick, we also need to make sure lookup keys are committed to
memory before setting refcount to 1, or a lockless reader could get a reference
on the old version of the object. Its key re-check could then pass the barrier.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
rcu: Add synchronize_sched_expedited() rcutorture doc + updates 2009-07-03T08:02:29+00:00 Paul E. McKenney paulmck@linux.vnet.ibm.com 2009-06-25T16:08:18+00:00 240ebbf81f149b11a31e060ebe5ee51a3c775360 This patch updates the rcutorture documentation to include updated output format. It also brings the RCU documentation up to date. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: akpm@linux-foundation.org Cc: torvalds@linux-foundation.org Cc: davem@davemloft.net Cc: dada1@cosmosbay.com Cc: zbr@ioremap.net Cc: jeff.chua.linux@gmail.com Cc: paulus@samba.org Cc: laijs@cn.fujitsu.com Cc: jengelh@medozas.de Cc: r000n@r000n.net Cc: benh@kernel.crashing.org Cc: mathieu.desnoyers@polymtl.ca LKML-Reference: <12459460983193-git-send-email-> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
This patch updates the rcutorture documentation to include
updated output format.  It also brings the RCU documentation up
to date.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: akpm@linux-foundation.org
Cc: torvalds@linux-foundation.org
Cc: davem@davemloft.net
Cc: dada1@cosmosbay.com
Cc: zbr@ioremap.net
Cc: jeff.chua.linux@gmail.com
Cc: paulus@samba.org
Cc: laijs@cn.fujitsu.com
Cc: jengelh@medozas.de
Cc: r000n@r000n.net
Cc: benh@kernel.crashing.org
Cc: mathieu.desnoyers@polymtl.ca
LKML-Reference: <12459460983193-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
trivial: Miscellaneous documentation typo fixes 2009-06-12T16:01:47+00:00 Matt LaPlante kernel1@cyberdogtech.com 2009-04-27T13:06:31+00:00 19f594600110377ec4037fdf7fb93a25ec516212 Fix various typos in documentation txts. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> 
Fix various typos in documentation txts.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
rcu: Update RCU tracing documentation for __rcu_pending 2009-04-14T09:33:43+00:00 Paul E. McKenney paulmck@linux.vnet.ibm.com 2009-04-14T04:31:18+00:00 6fd9b3a40b82081d9e6490b0d7cd656e9a78a134 This patch updates the RCU documentation to reflect the changes in tracing made in the previous patch in the set. Located-by: Anton Blanchard <anton@au1.ibm.com> Tested-by: Anton Blanchard <anton@au1.ibm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: anton@samba.org Cc: akpm@linux-foundation.org Cc: dipankar@in.ibm.com Cc: manfred@colorfullife.com Cc: cl@linux-foundation.org Cc: josht@linux.vnet.ibm.com Cc: schamp@sgi.com Cc: niv@us.ibm.com Cc: dvhltc@us.ibm.com Cc: ego@in.ibm.com Cc: laijs@cn.fujitsu.com Cc: rostedt@goodmis.org Cc: peterz@infradead.org Cc: penberg@cs.helsinki.fi Cc: andi@firstfloor.org Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> LKML-Reference: <12396834792865-git-send-email-> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
This patch updates the RCU documentation to reflect the changes in
tracing made in the previous patch in the set.

Located-by: Anton Blanchard <anton@au1.ibm.com>
Tested-by: Anton Blanchard <anton@au1.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: anton@samba.org
Cc: akpm@linux-foundation.org
Cc: dipankar@in.ibm.com
Cc: manfred@colorfullife.com
Cc: cl@linux-foundation.org
Cc: josht@linux.vnet.ibm.com
Cc: schamp@sgi.com
Cc: niv@us.ibm.com
Cc: dvhltc@us.ibm.com
Cc: ego@in.ibm.com
Cc: laijs@cn.fujitsu.com
Cc: rostedt@goodmis.org
Cc: peterz@infradead.org
Cc: penberg@cs.helsinki.fi
Cc: andi@firstfloor.org
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
LKML-Reference: <12396834792865-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Doc: Fix spelling in RCU/rculist_nulls.txt. 2009-04-02T08:33:51+00:00 Jesper Dangaard Brouer hawk@comx.dk 2009-03-31T09:36:48+00:00 edd4070f5d943b35e3e1a2e5e95e4a2eebb11d53 Doc: Fix spelling in RCU/rculist_nulls.txt. Trival spelling fixes in RCU/rculist_nulls.txt. Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk> Tested-by: Jarek Poplawski <jarkao2@gmail.com;-> Signed-off-by: David S. Miller <davem@davemloft.net> 
Doc: Fix spelling in RCU/rculist_nulls.txt.

Trival spelling fixes in RCU/rculist_nulls.txt.

Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Tested-by: Jarek Poplawski <jarkao2@gmail.com;->
Signed-off-by: David S. Miller <davem@davemloft.net>
Doc: Fix wrong API example usage of call_rcu(). 2009-04-02T08:33:50+00:00 Jesper Dangaard Brouer hawk@comx.dk 2009-03-29T23:03:01+00:00 3943ac5d99ec024f97442e5f3def1034bb0b1bb0 At some point the API of call_rcu() changed from three parameters to two parameters, correct the documentation. One confusing thing in RCU/listRCU.txt, which is NOT fixed in this patch, is that no reason or explaination is given for using call_rcu() instead of the normal synchronize_rcu() call. Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk> Signed-off-by: David S. Miller <davem@davemloft.net> 
At some point the API of call_rcu() changed from three parameters
to two parameters, correct the documentation.

One confusing thing in RCU/listRCU.txt, which is NOT fixed in this patch,
is that no reason or explaination is given for using call_rcu() instead of
the normal synchronize_rcu() call.

Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Doc: Fix missing whitespaces in RCU documentation. 2009-04-02T08:33:50+00:00 Jesper Dangaard Brouer hawk@comx.dk 2009-03-29T23:02:56+00:00 9ba30d74446dd0629d797ecd038379725d351bc6 Trivial fix while reading through the RCU docs. Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk> Signed-off-by: David S. Miller <davem@davemloft.net> 
Trivial fix while reading through the RCU docs.

Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>