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From: Eric Saint-Etienne <eric.saintetienne@gmail.com>
Date: Mon, 26 Mar 2012 17:04:16 +0100
Message-ID: <CACJX+52cpn1z78WB-81P+16sBQdk_BmwZABs=tp97wTQdyyiew@mail.gmail.com>
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Subject: GEOM and the non-sleeping path
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Is this still true that a geom class cannot sleep i nthe I/O path?

Because there are several (all?) geom classes which lock a MTX_DEF
mutex in the start() function.
For instance md and ggate do this.

Furthermore, no geom class use a MTX_SPIN mutex to make sure they will
not sleep in the I/O path.

-eric