Date: Sun, 31 Aug 2003 00:29:34 -0700 (PDT) From: Jeff Roberson <jeff@FreeBSD.org> To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: cvs commit: src/sys/ufs/ffs ffs_softdep.c Message-ID: <200308310729.h7V7TYfr015861@repoman.freebsd.org>
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jeff 2003/08/31 00:29:34 PDT
FreeBSD src repository
Modified files:
sys/ufs/ffs ffs_softdep.c
Log:
- Don't acquire the vnode interlock in drain_output(). Instead, require the
caller to acquire it. This permits drain_output() to be done atomically
with other operations as well as reducing the number of lock operations.
- Assert that the proper locks are held in drain_output().
- Change getdirtybuf() to accept a mutex as an argument. This mutex is used
to protect the vnode's buf list and the BKGRDWAIT flag. This lock is
dropped when we successfully acquire a buffer and held on return
otherwise. These semantics reduce the number of cumbersome cases in
calling code.
- Pass the mtx from getdirtybuf() into interlocked_sleep() and allow this
mutex to be used as the interlock argument to BUF_LOCK() in the LOCKBUF
case of interlocked_sleep().
- Change the return value of getdirtybuf() to be the resulting locked buffer
or NULL otherwise. This is for callers who pass in a list head that
requires a lock. It is necessary since the lock that protects the list
head must be dropped in getdirtybuf() so that we don't have a lock order
reversal with the buf queues lock in bremfree().
- Adjust all callers of getdirtybuf() to match the new semantics.
- Add a comment in indir_trunc() that points at unlocked access to a buf.
This may also be one of the last instances of incore() in the tree.
Revision Changes Path
1.141 +77 -53 src/sys/ufs/ffs/ffs_softdep.c
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