Giant-free ahc?

Daniel Eriksson daniel_k_eriksson at telia.com
Mon Oct 11 11:48:43 PDT 2004


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




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