From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Date: Mon, 13 Aug 2012 01:54:29 +0200 Subject: [U-Boot] usb_test_unit_ready called every block read - performance In-Reply-To: References: Message-ID: <201208130154.30182.marex@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Dear Jim Shimer, > While tuning ext2load, we found that usb_test_unit_ready was being called > every block read. We compared the usb block storage to the scsi block > storage cmd_scsi.c, and found that the scsi device was only calling its > scsi_setup_test_unit_ready() during scsi_can. It appears that > usb_test_unit_ready() really only needs to be called once during > usb_stor_scan(), via usb_stor_get_info(). Is there a particular reason > usb_test_unit_ready is called for every block read, or do you think its ok > to only call during usb_stor_scan()? We're finding this speeds up ext2load > quite a bit. Jim, did we get anywhere on this one ? Can you try with the new ext4 code in Wolfgangs' u-boot-master/ext4 branch? > Regards, > Jim Best regards, Marek Vasut