From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Tolpin <dvd@davidashen.net>
Message-Id: <200403071755.i27HtbcR080605@adat.davidashen.net>
To: 9fans@cse.psu.edu
Content-Type: text/plain; charset=KOI8-R
Subject: [9fans] kfs locks
Date: Sun,  7 Mar 2004 21:55:37 +0400
Topicbox-Message-UUID: 1f3b59a8-eacd-11e9-9e20-41e7f4b1d025

Hi,

cmd_sync sets 

rlock(&mainlock); 

...
syncall();
...
runlock(&mainlock);

...
syncproc, the background process forked by kfs, runs 
syncblock()
without setting rlock(&mainlock)

Can it the cause that I am getting wrenwrite errors after
'check f' on startup, if cmd_sync is not called after cmd_check
and before forking 'sync' and 'serve'?

I am still struggling to understand the problem. I've changed
the disk to be sure and still can reproduce the error if cmd_sync
is not called after the list of free blocks is rebuilt after blackdown.

David Tolpin