Date: Wed, 15 Mar 2006 23:43:17 GMT From: Peter Wemm <peter@FreeBSD.org> To: Perforce Change Reviews <perforce@freebsd.org> Subject: PERFORCE change 93380 for review Message-ID: <200603152343.k2FNhHBN005065@repoman.freebsd.org>
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http://perforce.freebsd.org/chv.cgi?CH=93380 Change 93380 by peter@peter_melody on 2006/03/15 23:43:08 Slight optimization. If we're going to test the map for nonzero, use that to terminate the loop. Use the loop termination condition to measure success. Affected files ... .. //depot/projects/hammer/sys/amd64/amd64/pmap.c#143 edit Differences ... ==== //depot/projects/hammer/sys/amd64/amd64/pmap.c#143 (text+ko) ==== @@ -1593,13 +1593,12 @@ pc = TAILQ_FIRST(&pmap->pm_pvchunk); if (pc != NULL) { for (field = 0; field < _NPCM; field++) { - bit = -1; - if (pc->pc_map[field]) + if (pc->pc_map[field]) { bit = bsfq(pc->pc_map[field]); - if (bit >= 0) break; + } } - if (bit >= 0) { + if (field < _NPCM) { pv = &pc->pc_pventry[field * 64 + bit]; pc->pc_map[field] &= ~(1ul << bit); /* If this was the last item, move it to tail */
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