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Message-ID: <863e9df20805220007r36089c93p6f2a787818aa150c@mail.gmail.com>
Date: Thu, 22 May 2008 12:37:20 +0530
From: "Abhishek Sagar" <sagar.abhishek@gmail.com>
To: "Srinivasa D S" <srinivasa@in.ibm.com>,
       "Jim Keniston" <jkenisto@us.ibm.com>
Subject: Re: [RFC] [PATCH] To improve kretprobe scalability
Cc: linux-kernel@vger.kernel.org, "Andrew Morton" <akpm@linux-foundation.org>,
       "Ananth Mavinakayanahalli" <ananth@in.ibm.com>,
       "Masami Hiramatsu" <mhiramat@redhat.com>,
       "Srikar Dronamraju" <srikar@linux.vnet.ibm.com>
In-Reply-To: <200805210632.17655.srinivasa@in.ibm.com>
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On 5/21/08, Srinivasa D S <srinivasa@in.ibm.com> wrote:
>  Solution:
>    1) Instead of having one global lock to protect kretprobe instances
>  present in kretprobe object and kretprobe hash table. We will have two locks,
>  one lock for protecting kretprobe hash table and another lock for kretporbe
>  object.

Is it possible to get rid of the kretprobe hash table itself and lose
the kretprobe_lock? It seems like it is just doing a pid-to-instance
mapping. These return instances could be queued in the "current"
task_struct in a LIFO manner. Mutation to this per-task list can be
done with local irqs off...

--
Regards,
Abhishek Sagar