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Subject: Re: [PATCH] Fix deadlock in RPC scheduling code.
From: Trond Myklebust <trond.myklebust@fys.uio.no>
To: Aurelien Degremont <aurelien.degremont@cea.fr>
Cc: Jacques-Charles Lafoucriere <jc.lafoucriere@cea.fr>,
       Bruno Faccini <bruno.faccini@bull.net>, linux-kernel@vger.kernel.org
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Date: Mon, 13 Mar 2006 11:08:23 -0500
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On Mon, 2006-03-13 at 16:16 +0100, Aurelien Degremont wrote:

> IMO, the code will still hang because, the list_for_each_entry_safe() 
> loop will never complete, even with the new scheme. Indeed, the loop 
> call __rpc_wake_up_task() will try to set RPC_TASK_WAKEUP bit, but it is 
> already set by rpc_wake_up_task(), so it hangs...

Look again. There is nothing that loops in __rpc_wake_up_task(). If the
RPC_TASK_WAKEUP is already set, then the function exits.

Cheers,
  Trond