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From: "Daniel Eriksson" <daniel_k_eriksson@telia.com>
To: <freebsd-current@freebsd.org>
Date: Mon, 11 Oct 2004 20:48:38 +0200
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Subject: Giant-free ahc?
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Is anyone working on fine-grained locking for the ahc driver?

I just upgraded one of my servers from UP to SMP, and noticed that *Giant
showed up a lot when running top for processes accessing data on the SCSI
discs. It could be a GIANT lock for some other resource of course, but since
the ahc driver reports [GIANT-LOCKED] during boot, and since all the
processes were accessing data on SCSI discs I just assumed it was waiting
for a lock in the ahc driver.

Is there a simple way to figure out which resource the processes are waiting
for (without compiling in any additional debugging)?

/Daniel Eriksson