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Date: Tue, 20 Sep 2011 10:28:43 -0400
From: Christoph Hellwig <hch@infradead.org>
To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>,
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Subject: Re: [PATCH v5 3.1.0-rc4-tip 0/26]   Uprobes patchset with perf probe
 support
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 <20110920141204.GC6568@linux.vnet.ibm.com>
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On Tue, Sep 20, 2011 at 07:42:04PM +0530, Srikar Dronamraju wrote:
> I could use any other inode/file/mapping based sleepable lock that is of
> higher order than mmap_sem. Can you please let me know if we have
> alternatives.

Please do not overload unrelated locks for this, but add a specific one.

There's two options:

 (a) add it to the inode (conditionally)
 (b) use global, hashed locks

I think (b) is good enough as adding/removing probes isn't exactly the
most critical fast path.