Hi,
fs/gfs2/rgrp.c: In function ‘gfs2_bitfit’:
fs/gfs2/rgrp.c:139: warning: assignment from incompatible pointer type
Please can you send me a fix for the above. Thanks,
Steve.
On Tue, 2007-12-11 at 19:00 -0600, Bob Peterson wrote:
> Hi,
>
> I eliminated the passing of an unused parameter into gfs2_bitfit called rgd.
>
> This also changes the gfs2_bitfit code that searches for free (or used)
> blocks.
> Before, the code was trying to check for bytes that indicated 4 blocks in
> the undesired state. The problem is, it was spending more time trying to
> do this than it actually was saving. This version only optimizes the case
> where we're looking for free blocks, and it checks a machine word at a time.
> So on 32-bit machines, it will check 32-bits (16 blocks) and on 64-bit
> machines, it will check 64-bits (32 blocks) at a time. The compiler
> optimizes that quite well and we save some time, especially when running
> through full bitmaps (like the bitmaps allocated for the journals).
>
> There's probably a more elegant or optimized way to do this, but I haven't
> thought of it yet. I'm open to suggestions.
>
> Regards,
>
> Bob Peterson
> Red Hat GFS
>
> Signed-off-by: Bob Peterson <[EMAIL PROTECTED]>
> --
> .../fs/gfs2/rgrp.c | 54
> +++++++++++---------
> 70 files changed, 29 insertions(+), 25 deletions(-)
>
> diff --git a/gfs2-2.6.git.patch2/fs/gfs2/rgrp.c
> b/gfs2-2.6.git.patch3/fs/gfs2/rgrp.c
> index e0ee195..d7ff9cf 100644
> --- a/gfs2-2.6.git.patch2/fs/gfs2/rgrp.c
> +++ b/gfs2-2.6.git.patch3/fs/gfs2/rgrp.c
> @@ -126,41 +126,46 @@ static unsigned char gfs2_testbit(struct gfs2_rgrpd
> *rgd, unsigned char *buffer,
> * Return: the block number (bitmap buffer scope) that was found
> */
>
> -static u32 gfs2_bitfit(struct gfs2_rgrpd *rgd, unsigned char *buffer,
> - unsigned int buflen, u32 goal,
> - unsigned char old_state)
> +static u32 gfs2_bitfit(unsigned char *buffer, unsigned int buflen, u32 goal,
> + unsigned char old_state)
> {
> - unsigned char *byte, *end, alloc;
> + unsigned char *byte;
> u32 blk = goal;
> - unsigned int bit;
> + unsigned int bit, bitlong;
> + unsigned long *plong, plong55;
> + static int c = 0;
>
> byte = buffer + (goal / GFS2_NBBY);
> + plong = buffer + (goal / GFS2_NBBY);
> bit = (goal % GFS2_NBBY) * GFS2_BIT_SIZE;
> - end = buffer + buflen;
> - alloc = (old_state == GFS2_BLKST_FREE) ? 0x55 : 0;
> -
> - while (byte < end) {
> - /* If we're looking for a free block we can eliminate all
> - bitmap settings with 0x55, which represents four data
> - blocks in a row. If we're looking for a data block, we can
> - eliminate 0x00 which corresponds to four free blocks. */
> - if ((*byte & 0x55) == alloc) {
> - blk += (8 - bit) >> 1;
> -
> - bit = 0;
> - byte++;
> -
> + bitlong = bit;
> +#if BITS_PER_LONG == 32
> + plong55 = 0x55555555;
> +#else
> + plong55 = 0x5555555555555555;
> +#endif
> + while (byte < buffer + buflen) {
> +
> + if (bitlong == 0 && old_state == 0 && *plong == plong55) {
> + plong++;
> + byte += sizeof(unsigned long);
> + blk += sizeof(unsigned long) * GFS2_NBBY;
> continue;
> }
> -
> - if (((*byte >> bit) & GFS2_BIT_MASK) == old_state)
> + if (((*byte >> bit) & GFS2_BIT_MASK) == old_state) {
> + c++;
> return blk;
> -
> + }
> bit += GFS2_BIT_SIZE;
> if (bit >= 8) {
> bit = 0;
> byte++;
> }
> + bitlong += GFS2_BIT_SIZE;
> + if (bitlong >= sizeof(unsigned long) * 8) {
> + bitlong = 0;
> + plong++;
> + }
>
> blk++;
> }
> @@ -1318,11 +1323,10 @@ static u32 rgblk_search(struct gfs2_rgrpd *rgd, u32
> goal,
> /* The GFS2_BLKST_UNLINKED state doesn't apply to the clone
> bitmaps, so we must search the originals for that. */
> if (old_state != GFS2_BLKST_UNLINKED && bi->bi_clone)
> - blk = gfs2_bitfit(rgd, bi->bi_clone + bi->bi_offset,
> + blk = gfs2_bitfit(bi->bi_clone + bi->bi_offset,
> bi->bi_len, goal, old_state);
> else
> - blk = gfs2_bitfit(rgd,
> - bi->bi_bh->b_data + bi->bi_offset,
> + blk = gfs2_bitfit(bi->bi_bh->b_data + bi->bi_offset,
> bi->bi_len, goal, old_state);
> if (blk != BFITNOENT)
> break;
>
>
