lkml.org 
[lkml]   [2011]   [May]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [tip:core/rcu] Revert "rcu: Decrease memory-barrier usage based on semi-formal proof"
On 05/20/2011 03:42 PM, Paul E. McKenney wrote:
> On Fri, May 20, 2011 at 02:04:06PM -0700, Yinghai Lu wrote:
>> On 05/19/2011 02:37 PM, tip-bot for Paul E. McKenney wrote:
>>> Commit-ID: 80d02085d99039b3b7f3a73c8896226b0cb1ba07
>>> Gitweb: http://git.kernel.org/tip/80d02085d99039b3b7f3a73c8896226b0cb1ba07
>>> Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
>>> AuthorDate: Thu, 12 May 2011 01:08:07 -0700
>>> Committer: Ingo Molnar <mingo@elte.hu>
>>> CommitDate: Thu, 19 May 2011 23:25:29 +0200
>>>
>>> Revert "rcu: Decrease memory-barrier usage based on semi-formal proof"
>>>
>>> This reverts commit e59fb3120becfb36b22ddb8bd27d065d3cdca499.
>>>
>>> This reversion was due to (extreme) boot-time slowdowns on SPARC seen by
>>> Yinghai Lu and on x86 by Ingo
>>> .
>>> This is a non-trivial reversion due to intervening commits.
>>>
>>> Conflicts:
>>>
>>> Documentation/RCU/trace.txt
>>> kernel/rcutree.c
>>>
>>> Signed-off-by: Ingo Molnar <mingo@elte.hu>
>>> ---
>>> Documentation/RCU/trace.txt | 17 ++++--
>>> kernel/rcutree.c | 130 ++++++++++++++++++++++++------------------
>>> kernel/rcutree.h | 9 ++-
>>> kernel/rcutree_plugin.h | 7 +-
>>> kernel/rcutree_trace.c | 12 ++--
>>> 5 files changed, 102 insertions(+), 73 deletions(-)
>>>
>>
>> current tip/master that have this reverting and without setting DEBUG_LOCKING_API_SELFTESTS
>>
>> still get delay
>>
>> [ 35.419453] cpu_dev_init done
>> [ 128.981770] memory_dev_init done
>>
>> should take only 3 or 4 seconds.
>
> Thank you for checking this out.
>
> This is with the same configuration you sent earlier? (Other than the
> DEBUG_LOCKING_API_SELFTESTS, of course.)
>

8 socket westmere-ex. and compiled with gcc from opensuse 11.3.

if compile kernel from fedora 14, there will be not delay.

Thanks

Yinghai


\
 
 \ /
  Last update: 2011-05-21 01:13    [from the cache]
©2003-2011 Jasper Spaans