Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757613AbYBDTPT (ORCPT ); Mon, 4 Feb 2008 14:15:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755548AbYBDTPG (ORCPT ); Mon, 4 Feb 2008 14:15:06 -0500 Received: from styx.suse.cz ([82.119.242.94]:49745 "EHLO duck.suse.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754892AbYBDTPF (ORCPT ); Mon, 4 Feb 2008 14:15:05 -0500 Date: Mon, 4 Feb 2008 20:15:03 +0100 From: Jan Kara To: Marcin Slusarz Cc: LKML Subject: Re: [PATCH 10/10] udf: constify udf_bitmap_lookup array Message-ID: <20080204191503.GM3426@duck.suse.cz> References: <1201727040-6769-1-git-send-email-marcin.slusarz@gmail.com> <1201727040-6769-11-git-send-email-marcin.slusarz@gmail.com> <20080131165244.GJ1461@duck.suse.cz> <20080202213659.GA8495@joi> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080202213659.GA8495@joi> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2758 Lines: 85 On Sat 02-02-08 22:37:07, Marcin Slusarz wrote: > On Thu, Jan 31, 2008 at 05:52:44PM +0100, Jan Kara wrote: > > On Wed 30-01-08 22:04:00, marcin.slusarz@gmail.com wrote: > > > udf_bitmap_lookup never changes, so constify it > > > > > > Signed-off-by: Marcin Slusarz > > > Cc: Jan Kara > > Hmm, rather than doing this, could you change the function to use > > standard functions for counting set bits? I guess bitmap_weight() in > > include/linux/bitmap.h should be what we need... Thanks. > > --- > udf: convert udf_count_free_bitmap to use bitmap_weight > > replace handwritten bits counting with bitmap_weight > > Signed-off-by: Marcin Slusarz > Cc: Jan Kara Acked-by: Jan Kara Honza > --- > fs/udf/super.c | 17 +++++------------ > 1 files changed, 5 insertions(+), 12 deletions(-) > > diff --git a/fs/udf/super.c b/fs/udf/super.c > index 3afe764..0dcee12 100644 > --- a/fs/udf/super.c > +++ b/fs/udf/super.c > @@ -53,6 +53,7 @@ > #include > #include > #include > +#include > #include > > #include > @@ -1969,10 +1970,6 @@ static int udf_statfs(struct dentry *dentry, struct kstatfs *buf) > return 0; > } > > -static unsigned char udf_bitmap_lookup[16] = { > - 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4 > -}; > - > static unsigned int udf_count_free_bitmap(struct super_block *sb, > struct udf_bitmap *bitmap) > { > @@ -1982,7 +1979,6 @@ static unsigned int udf_count_free_bitmap(struct super_block *sb, > int block = 0, newblock; > kernel_lb_addr loc; > uint32_t bytes; > - uint8_t value; > uint8_t *ptr; > uint16_t ident; > struct spaceBitmapDesc *bm; > @@ -2008,13 +2004,10 @@ static unsigned int udf_count_free_bitmap(struct super_block *sb, > ptr = (uint8_t *)bh->b_data; > > while (bytes > 0) { > - while ((bytes > 0) && (index < sb->s_blocksize)) { > - value = ptr[index]; > - accum += udf_bitmap_lookup[value & 0x0f]; > - accum += udf_bitmap_lookup[value >> 4]; > - index++; > - bytes--; > - } > + u32 cur_bytes = min_t(u32, bytes, sb->s_blocksize - index); > + accum += bitmap_weight((const unsigned long *)(ptr + index), > + cur_bytes * 8); > + bytes -= cur_bytes; > if (bytes) { > brelse(bh); > newblock = udf_get_lb_pblock(sb, loc, ++block); > -- > 1.5.3.7 > -- Jan Kara SUSE Labs, CR -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/