From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from d01relay02.pok.ibm.com (d01relay02.pok.ibm.com [9.56.227.234]) by e6.ny.us.ibm.com (8.13.8/8.13.8) with ESMTP id l4OCDBBa016985 for ; Thu, 24 May 2007 08:13:11 -0400 Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay02.pok.ibm.com (8.13.8/8.13.8/NCO v8.3) with ESMTP id l4OCC9uR523064 for ; Thu, 24 May 2007 08:12:09 -0400 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id l4OCC906025149 for ; Thu, 24 May 2007 08:12:09 -0400 Date: Thu, 24 May 2007 08:12:08 -0400 From: Dave Kleikamp Message-Id: <20070524121208.13533.24962.sendpatchset@kleikamp.austin.ibm.com> In-Reply-To: <20070524121130.13533.32563.sendpatchset@kleikamp.austin.ibm.com> References: <20070524121130.13533.32563.sendpatchset@kleikamp.austin.ibm.com> Subject: [RFC:PATCH 007/012] Avoid page_to_pfn() on tail page Sender: owner-linux-mm@kvack.org Return-Path: To: linux-mm List-ID: Avoid page_to_pfn() on tail page On ppc64, we don't need bounce buffers to do I/O. This will need more work for other architectures. Signed-off-by: Dave Kleikamp --- block/ll_rw_blk.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff -Nurp linux006/block/ll_rw_blk.c linux007/block/ll_rw_blk.c --- linux006/block/ll_rw_blk.c 2007-05-21 15:14:57.000000000 -0500 +++ linux007/block/ll_rw_blk.c 2007-05-23 22:53:12.000000000 -0500 @@ -1221,7 +1221,8 @@ void blk_recount_segments(request_queue_ * considered part of another segment, since that might * change with the bounce page. */ - high = page_to_pfn(bv->bv_page) > q->bounce_pfn; + high = (!PageFileTail(bv->bv_page) && + page_to_pfn(bv->bv_page) > q->bounce_pfn); if (high || highprv) goto new_hw_segment; if (cluster) { -- David Kleikamp IBM Linux Technology Center -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org