Messages in this thread | | | Subject | Re: [PATCH 2/2] fat: optimize fat_count_free_clusters() | From | OGAWA Hirofumi <> | Date | Tue, 06 Nov 2007 11:07:12 +0900 |
| |
Andrew Morton <akpm@linux-foundation.org> writes:
>> +/* 128kb is the whole sectors for FAT12 and FAT16 */ >> +#define FAT_READA_SIZE (128 * 1024) >> + >> +static void fat_ent_reada(struct super_block *sb, struct fat_entry *fatent, >> + unsigned long reada_blocks) >> +{ >> + struct fatent_operations *ops = MSDOS_SB(sb)->fatent_ops; >> + sector_t blocknr; >> + int i, offset; >> + >> + ops->ent_blocknr(sb, fatent->entry, &offset, &blocknr); >> + >> + for (i = 0; i < reada_blocks; i++) >> + sb_breadahead(sb, blocknr + i); >> +} > > You might find that it's simpler and faster to call > page_cache_sync_readahead() against sb->s_bdev->bd_inode->i_mapping. > > Or maybe not - that requires a struct file_ra_state. We _used_ to have a > nice simple read-some-stuff-into-pagecache function which didn't need an > ra_state but that seems to have disappeared in the various recent readahead > churn. Oh well.
Yes. I found it, but I gave up for now by file_ra_state. Also I'd like to use a large block to read FAT. I'll rethink this code after large block was merged.
Thanks. -- OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> - 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/
| |