On Tue, Dec 21, 2010 at 06:29:26PM +1100, Dave Chinner wrote: > From: Dave Chinner <dchinner@xxxxxxxxxx> > > log->l_tail_lsn is currently protected by the log grant lock. The > lock is only needed for serialising readers against writers, so we > don't really need the lock if we make the l_tail_lsn variable an > atomic. Converting the l_tail_lsn variable to an atomic64_t means we > can start to peel back the grant lock from various operations. > > Also, provide functions to safely crack an atomic LSN variable into > it's component pieces and to recombined the components into an > atomic variable. Use them where appropriate. > > This also removes the need for explicitly holding a spinlock to read > the l_tail_lsn on 32 bit platforms. > > Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx> Looks good, Reviewed-by: Christoph Hellwig <hch@xxxxxx> > /* log->l_tail_lsn = 0x100000000LL; cycle = 1; current block = 0 */ > - log->l_tail_lsn = xlog_assign_lsn(1, 0); > - atomic64_set(&log->l_last_sync_lsn, xlog_assign_lsn(1, 0)); > + xlog_assign_atomic_lsn(&log->l_tail_lsn, 1, 0); > + xlog_assign_atomic_lsn(&log->l_last_sync_lsn, 1, 0); It might be worth to remove the rather pointless comment above. > BTOBB(XLOG_MAX_ICLOGS << (xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? \ > XLOG_MAX_RECORD_BSHIFT : XLOG_BIG_RECORD_BSHIFT)) > > - > static inline xfs_lsn_t xlog_assign_lsn(uint cycle, uint block) spurious whitespace change _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
