From: "Paul E. McKenney" Subject: Re: 2.6.25-git2: BUG: unable to handle kernel paging request at ffffffffffffffff Date: Sun, 20 Apr 2008 22:47:29 -0700 Message-ID: <20080421054729.GA19864@linux.vnet.ibm.com> References: <200804191522.54334.rjw@sisk.pl> <200804202104.24037.rjw@sisk.pl> <20080421011855.GA6243@gondor.apana.org.au> <20080421020806.GL20138@linux.vnet.ibm.com> <20080421045911.GA1812@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Linus Torvalds , "Rafael J. Wysocki" , LKML , Ingo Molnar , Andrew Morton , linux-ext4@vger.kernel.org To: Herbert Xu Return-path: Received: from e31.co.us.ibm.com ([32.97.110.149]:35414 "EHLO e31.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751797AbYDUFrc (ORCPT ); Mon, 21 Apr 2008 01:47:32 -0400 Content-Disposition: inline In-Reply-To: <20080421045911.GA1812@linux.vnet.ibm.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Sun, Apr 20, 2008 at 09:59:11PM -0700, Paul E. McKenney wrote: > And here is an update with one bug fixed -- testing continues. > This is an update of http://lkml.org/lkml/2008/4/20/217, deleting > list_for_each_safe_rcu() and fixing hlist_for_each_entry_rcu(). > Testing continues... And it passes. Thanx, Paul > Signed-off-by: Paul E. McKenney > --- > > list.h | 48 +++++++++++++++--------------------------------- > 1 file changed, 15 insertions(+), 33 deletions(-) > > diff -urpNa -X dontdiff linux-2.6.25/include/linux/list.h linux-2.6.25-rcu-list/include/linux/list.h > --- linux-2.6.25/include/linux/list.h 2008-04-16 19:49:44.000000000 -0700 > +++ linux-2.6.25-rcu-list/include/linux/list.h 2008-04-20 21:48:29.000000000 -0700 > @@ -631,31 +631,14 @@ static inline void list_splice_init_rcu( > * as long as the traversal is guarded by rcu_read_lock(). > */ > #define list_for_each_rcu(pos, head) \ > - for (pos = (head)->next; \ > - prefetch(rcu_dereference(pos)->next), pos != (head); \ > - pos = pos->next) > + for (pos = rcu_dereference((head)->next); \ > + prefetch(pos->next), pos != (head); \ > + pos = rcu_dereference(pos->next)) > > #define __list_for_each_rcu(pos, head) \ > - for (pos = (head)->next; \ > - rcu_dereference(pos) != (head); \ > - pos = pos->next) > - > -/** > - * list_for_each_safe_rcu > - * @pos: the &struct list_head to use as a loop cursor. > - * @n: another &struct list_head to use as temporary storage > - * @head: the head for your list. > - * > - * Iterate over an rcu-protected list, safe against removal of list entry. > - * > - * This list-traversal primitive may safely run concurrently with > - * the _rcu list-mutation primitives such as list_add_rcu() > - * as long as the traversal is guarded by rcu_read_lock(). > - */ > -#define list_for_each_safe_rcu(pos, n, head) \ > - for (pos = (head)->next; \ > - n = rcu_dereference(pos)->next, pos != (head); \ > - pos = n) > + for (pos = rcu_dereference((head)->next); \ > + pos != (head); \ > + pos = rcu_dereference(pos->next)) > > /** > * list_for_each_entry_rcu - iterate over rcu list of given type > @@ -668,10 +651,9 @@ static inline void list_splice_init_rcu( > * as long as the traversal is guarded by rcu_read_lock(). > */ > #define list_for_each_entry_rcu(pos, head, member) \ > - for (pos = list_entry((head)->next, typeof(*pos), member); \ > - prefetch(rcu_dereference(pos)->member.next), \ > - &pos->member != (head); \ > - pos = list_entry(pos->member.next, typeof(*pos), member)) > + for (pos = list_entry(rcu_dereference((head)->next), typeof(*pos), member); \ > + prefetch(pos->member.next), &pos->member != (head); \ > + pos = list_entry(rcu_dereference(pos->member.next), typeof(*pos), member)) > > > /** > @@ -686,9 +668,9 @@ static inline void list_splice_init_rcu( > * as long as the traversal is guarded by rcu_read_lock(). > */ > #define list_for_each_continue_rcu(pos, head) \ > - for ((pos) = (pos)->next; \ > - prefetch(rcu_dereference((pos))->next), (pos) != (head); \ > - (pos) = (pos)->next) > + for ((pos) = rcu_dereference((pos)->next); \ > + prefetch((pos)->next), (pos) != (head); \ > + (pos) = rcu_dereference((pos)->next)) > > /* > * Double linked lists with a single pointer list head. > @@ -986,10 +968,10 @@ static inline void hlist_add_after_rcu(s > * as long as the traversal is guarded by rcu_read_lock(). > */ > #define hlist_for_each_entry_rcu(tpos, pos, head, member) \ > - for (pos = (head)->first; \ > - rcu_dereference(pos) && ({ prefetch(pos->next); 1;}) && \ > + for (pos = rcu_dereference((head)->first); \ > + pos && ({ prefetch(pos->next); 1;}) && \ > ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ > - pos = pos->next) > + pos = rcu_dereference(pos->next)) > > #else > #warning "don't include kernel headers in userspace"