Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932071Ab1F2O1D (ORCPT ); Wed, 29 Jun 2011 10:27:03 -0400 Received: from p3plsmtps2ded02.prod.phx3.secureserver.net ([208.109.80.59]:51175 "HELO p3plsmtps2ded02-02.prod.phx3.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1755987Ab1F2OWz (ORCPT ); Wed, 29 Jun 2011 10:22:55 -0400 From: "K. Y. Srinivasan" To: gregkh@suse.de, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, virtualization@lists.osdl.org Cc: "K. Y. Srinivasan" , Haiyang Zhang , Abhishek Kane , Hank Janssen Subject: [PATCH 30/40] Staging: hv: storvsc: Optimize the bounce buffer handling in the "read" case Date: Wed, 29 Jun 2011 07:39:27 -0700 Message-Id: <1309358377-8537-30-git-send-email-kys@microsoft.com> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1309358377-8537-1-git-send-email-kys@microsoft.com> References: <1309358301-8488-1-git-send-email-kys@microsoft.com> <1309358377-8537-1-git-send-email-kys@microsoft.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1468 Lines: 41 Optimize the bounce buffer handling in the "read" case. Copy to bounce buffers (if needed) when we initiate an I/O, only if we are performing a "write" operation. Signed-off-by: K. Y. Srinivasan Signed-off-by: Haiyang Zhang Signed-off-by: Abhishek Kane Signed-off-by: Hank Janssen --- drivers/staging/hv/storvsc_drv.c | 10 ++++------ 1 files changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c index c6838fd..23334ad 100644 --- a/drivers/staging/hv/storvsc_drv.c +++ b/drivers/staging/hv/storvsc_drv.c @@ -623,12 +623,10 @@ static int storvsc_queuecommand_lck(struct scsi_cmnd *scmnd, ALIGN(scsi_bufflen(scmnd), PAGE_SIZE) >> PAGE_SHIFT; - /* - * FIXME: We can optimize on reads by just skipping - * this - */ - copy_to_bounce_buffer(sgl, cmd_request->bounce_sgl, - scsi_sg_count(scmnd)); + if (vm_srb->data_in == WRITE_TYPE) + copy_to_bounce_buffer(sgl, + cmd_request->bounce_sgl, + scsi_sg_count(scmnd)); sgl = cmd_request->bounce_sgl; sg_count = cmd_request->bounce_sgl_count; -- 1.7.4.1 -- 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/