From owner-freebsd-hackers  Thu May 24  9: 2:19 2001
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Date: Thu, 24 May 2001 12:02:16 -0400 (EDT)
From: Zhihui Zhang <zzhang@cs.binghamton.edu>
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To: freebsd-hackers@freebsd.org
Subject: shared versus exclusive lock
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According to my reading of kern_lock.c, it does support shared lock.
However, we are still using LK_EXCLUSIVE mode more often than necessary.
If I want to look up a directory or to read a buffer, I should be able to
use the LK_SHARED lock. Right now, only few places I have found using
LK_SHARED, like in vn_read(). Is there any reason behind this?  If I want
to change this in my code, is there anything I should pay special
attention to? Thanks.

-Zhihui


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