Move synchronous page_cache_readahead_ondemand() call out of splice loop. This avoids one pointless page allocation/insertion in case of non-zero ra_pages, or many pointless readahead calls in case of zero ra_pages. Note that if a user sets ra_pages to less than PIPE_BUFFERS=16 pages, he will not get expected readahead behavior anyway. The splice code works in batches of 16 pages, which can be taken as another form of synchronous readahead. Signed-off-by: Fengguang Wu --- fs/splice.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) --- linux-2.6.22-rc3-mm1.orig/fs/splice.c +++ linux-2.6.22-rc3-mm1/fs/splice.c @@ -299,12 +299,16 @@ __generic_file_splice_read(struct file * * Lookup the (hopefully) full range of pages we need. */ spd.nr_pages = find_get_pages_contig(mapping, index, nr_pages, pages); + index += spd.nr_pages; /* * If find_get_pages_contig() returned fewer pages than we needed, - * allocate the rest. + * readahead/allocate the rest. */ - index += spd.nr_pages; + if (spd.nr_pages < nr_pages) + page_cache_readahead_ondemand(mapping, &in->f_ra, in, + NULL, index, nr_pages - spd.nr_pages); + while (spd.nr_pages < nr_pages) { /* * Page could be there, find_get_pages_contig() breaks on @@ -312,9 +316,6 @@ __generic_file_splice_read(struct file * */ page = find_get_page(mapping, index); if (!page) { - page_cache_readahead_ondemand(mapping, &in->f_ra, in, - NULL, index, nr_pages - spd.nr_pages); - /* * page didn't exist, allocate one. */ -- - 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/