Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753940Ab3E0QN1 (ORCPT ); Mon, 27 May 2013 12:13:27 -0400 Received: from mail-pd0-f170.google.com ([209.85.192.170]:40790 "EHLO mail-pd0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753025Ab3E0QN0 (ORCPT ); Mon, 27 May 2013 12:13:26 -0400 From: Ming Lei To: Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH 0/2] dma-unmap: allow to only unmap completed DMA buffer Date: Tue, 28 May 2013 00:13:05 +0800 Message-Id: <1369671187-24430-1-git-send-email-ming.lei@canonical.com> X-Mailer: git-send-email 1.7.9.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 687 Lines: 19 This patchset tries to loose the check on DMA buffer size in check_unmap() of dma-debug first, then only unmap the actual completed DMA buffer in USB unmap path. Considered that DMA unmapping often runs in hard irq context, the patch set may save irq handling time. And the improvement can be observed on ARMv7(Pandaboard) with the chage, at average ~25us is saved about ehci irq handling under usbnet ping test case. Thanks, -- Ming Lei -- 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/