Messages in this thread | | | Date | Fri, 05 Apr 2013 09:21:20 -0400 | From | Rik van Riel <> | Subject | Re: [PATCH -mm -next] ipc,sem: untangle RCU locking with find_alloc_undo |
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On 04/05/2013 12:38 AM, Mike Galbraith wrote: > On Tue, 2013-03-26 at 16:00 -0400, Rik van Riel wrote:
>> The ipc semaphore code has a nasty RCU locking tangle, with both >> find_alloc_undo and semtimedop taking the rcu_read_lock(). The >> code can be cleaned up somewhat by only taking the rcu_read_lock >> once. >> >> There are no other callers to find_alloc_undo. >> >> This should also solve the trinity issue reported by Sasha Levin. > > I take it this is on top of the patchlet Sasha submitted?
Indeed, and all the other fixes that got submitted :)
> (I hit rcu stall banging on patch set in rt with 60 synchronized core > executive model if I let it run long enough, fwtw)
What are you using to trigger an rcu stall?
>> Reported-by: Sasha Levin <sasha.levin@oracle.com> >> Signed-off-by: Rik van Riel <riel@redhat.com>
-- All rights reversed.
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