From 7e230f5774336c5c180d8aeab0e2cb1326c73fa3 Mon Sep 17 00:00:00 2001 From: Bob Peterson Date: Wed, 11 Sep 2013 13:44:02 -0500 Subject: [PATCH] GFS2: introduce bi_blocks for optimization This patch introduces a new field in the bitmap structure called bi_blocks. Its purpose is to save us from constantly multiplying bi_len by the constant GFS2_NBBY. It also paves the way for more optimization in a future patch. Signed-off-by: Bob Peterson Signed-off-by: Steven Whitehouse --- fs/gfs2/incore.h | 1 + fs/gfs2/rgrp.c | 6 +++++- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h index 26aabd7..f1a3243 100644 --- a/fs/gfs2/incore.h +++ b/fs/gfs2/incore.h @@ -71,6 +71,7 @@ struct gfs2_bitmap { u32 bi_offset; u32 bi_start; u32 bi_len; + u32 bi_blocks; }; struct gfs2_rgrpd { diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c index 7a6fa03..7d64a27 100644 --- a/fs/gfs2/rgrp.c +++ b/fs/gfs2/rgrp.c @@ -262,7 +262,7 @@ static int gfs2_rbm_from_block(struct gfs2_rbm *rbm, u64 block) rbm->bi = rbm->rgd->rd_bits; rbm->offset = (u32)(rblock); /* Check if the block is within the first block */ - if (rbm->offset < rbm->bi->bi_len * GFS2_NBBY) + if (rbm->offset < rbm->bi->bi_blocks) return 0; /* Adjust for the size diff between gfs2_meta_header and gfs2_rgrp */ @@ -743,18 +743,21 @@ static int compute_bitstructs(struct gfs2_rgrpd *rgd) bi->bi_offset = sizeof(struct gfs2_rgrp); bi->bi_start = 0; bi->bi_len = bytes; + bi->bi_blocks = bytes * GFS2_NBBY; /* header block */ } else if (x == 0) { bytes = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_rgrp); bi->bi_offset = sizeof(struct gfs2_rgrp); bi->bi_start = 0; bi->bi_len = bytes; + bi->bi_blocks = bytes * GFS2_NBBY; /* last block */ } else if (x + 1 == length) { bytes = bytes_left; bi->bi_offset = sizeof(struct gfs2_meta_header); bi->bi_start = rgd->rd_bitbytes - bytes_left; bi->bi_len = bytes; + bi->bi_blocks = bytes * GFS2_NBBY; /* other blocks */ } else { bytes = sdp->sd_sb.sb_bsize - @@ -762,6 +765,7 @@ static int compute_bitstructs(struct gfs2_rgrpd *rgd) bi->bi_offset = sizeof(struct gfs2_meta_header); bi->bi_start = rgd->rd_bitbytes - bytes_left; bi->bi_len = bytes; + bi->bi_blocks = bytes * GFS2_NBBY; } bytes_left -= bytes; -- 2.7.4