Commit Graph

8 Commits

Author SHA1 Message Date
Herbert Xu
b24d18aa74 [PATCH] list: add missing rcu_dereference on first element
It seems that all the list_*_rcu primitives are missing a memory barrier
on the very first dereference.  For example,

#define list_for_each_rcu(pos, head) \
	for (pos = (head)->next; prefetch(pos->next), pos != (head); \
		pos = rcu_dereference(pos->next))

It will go something like:

	pos = (head)->next

	prefetch(pos->next)

	pos != (head)

	do stuff

We're missing a barrier here.

	pos = rcu_dereference(pos->next)

		fetch pos->next

		barrier given by rcu_dereference(pos->next)

		store pos

Without the missing barrier, the pos->next value may turn out to be stale.
In fact, if "do stuff" were also dereferencing pos and relying on
list_for_each_rcu to provide the barrier then it may also break.

So here is a patch to make sure that we have a barrier for the first
element in the list.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-17 08:59:10 -07:00
Paul E. McKenney
cf4ef01440 [LIST]: Add docbook header comments for hlist_add_{before,after}_rcu()
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 16:11:00 -07:00
Robert Olsson
e5b4376074 [IPV4]: Prepare FIB core for RCU.
* RCU versions of hlist_***_rcu
* fib_alias partial rcu port just whats needed now.

Signed-off-by: Robert Olsson <Robert.Olsson@data.slu.se>
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 16:08:31 -07:00
Arnaldo Carvalho de Melo
8c60f3fab5 [CCID3]: Separate most of the packet history code
This also changes the list_for_each_entry_safe_continue behaviour to match its
kerneldoc comment, that is, to start after the pos passed.

Also adds several helper functions from previously open coded fragments, making
the code more clear.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-08-29 15:56:28 -07:00
Arnaldo Carvalho de Melo
74459dc7ba [LIST]: Introduce list_for_each_entry_safe_continue
Used in the dccp CCID3 code, that is going to be submitted RSN.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 15:50:04 -07:00
Paul E. McKenney
b2b1866006 [PATCH] RCU: clean up a few remaining synchronize_kernel() calls
2.6.12-rc6-mm1 has a few remaining synchronize_kernel()s, some (but not
all) in comments.  This patch changes these synchronize_kernel() calls (and
comments) to synchronize_rcu() or synchronize_sched() as follows:

- arch/x86_64/kernel/mce.c mce_read(): change to synchronize_sched() to
  handle races with machine-check exceptions (synchronize_rcu() would not cut
  it given RCU implementations intended for hardcore realtime use.

- drivers/input/serio/i8042.c i8042_stop(): change to synchronize_sched() to
  handle races with i8042_interrupt() interrupt handler.  Again,
  synchronize_rcu() would not cut it given RCU implementations intended for
  hardcore realtime use.

- include/*/kdebug.h comments: change to synchronize_sched() to handle races
  with NMIs.  As before, synchronize_rcu() would not cut it...

- include/linux/list.h comment: change to synchronize_rcu(), since this
  comment is for list_del_rcu().

- security/keys/key.c unregister_key_type(): change to synchronize_rcu(),
  since this is interacting with RCU read side.

- security/keys/process_keys.c install_session_keyring(): change to
  synchronize_rcu(), since this is interacting with RCU read side.

Signed-off-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:38 -07:00
Paul E. McKenney
e1ba0dab26 [PATCH] Fix comment in list.h that refers to nonexistent API
The hlist_for_each_entry_rcu() comment block refers to a nonexistent
hlist_add_rcu() API, needs to change to hlist_add_head_rcu().

Signed-off-by: Paul E. McKenney <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16 15:25:51 -07:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
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!
2005-04-16 15:20:36 -07:00