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[Xen-devel] [PATCH 0 of 4] xentrace [v2]: non-contiguous allocation of p

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Subject: [Xen-devel] [PATCH 0 of 4] xentrace [v2]: non-contiguous allocation of per-cpu buffer
From: Olaf Hering <olaf@xxxxxxxxx>
Date: Tue, 10 May 2011 16:32:35 +0200
Cc: George Dunlap <george.dunlap@xxxxxxxxxx>
Delivery-date: Tue, 10 May 2011 07:34:31 -0700
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This series implements non-contiguous trace buffers.

There was an overflow in the offset calculation because it was stored in
an int. Also the calculation of the per-cpu buffer did not take the type
of the offset value into account. This was the reason why I ran into the
checks in bogus(). The crash in out_dealloc: was caused by the lack of
check for the offset value.

Regarding the math added to next_record() another array of pointers could be
added to remove the mfn_to_virt() calls. In my testing 9343 trace pages on 8
cpus are used. Such an array would required additional (9343*8*8)/1024=583Kb.
Which is not too much, given the amount of 291MB tracebuffers.
Such a change is not part of this series.


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