On Tue, 10 Jul 2007 [EMAIL PROTECTED] wrote: > This is a note to let you know that I've just added the patch titled > > Subject: USB: add usb_autopm_get_interface_burst() > > to my gregkh-2.6 tree. Its filename is > > usb-add-usb_autopm_get_interface_burst.patch > > This tree can be found at > http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/patches/ > > > >From [EMAIL PROTECTED] Fri Jul 6 11:21:32 2007 > From: Alan Stern <[EMAIL PROTECTED]> > Date: Fri, 6 Jul 2007 14:21:26 -0400 (EDT) > Subject: USB: add usb_autopm_get_interface_burst() > To: Greg KH <[EMAIL PROTECTED]> > Cc: USB development list <linux-usb-devel@lists.sourceforge.net> > Message-ID: <[EMAIL PROTECTED]> > > > This patch (as929) adds usb_autopm_get_interface_burst() to the > autosuspend programming interface. It is intended for situations > where I/O events occur in bursts of activity; it reduces overhead by > not cancelling the device's autosuspend timer.
Ironically, I just got a message from Thomas Gleixner indicating this patch is unnecessary. My own tests confirm his conclusion; there was no measurable difference in CPU utilization when reading a flash storage device with or without the burst-mode suspend routine. So I would like to withdraw this patch. The following usb-storage-implement-autosuspend.patch (as930) will then need the adjustment below (it can easily be merged into that patch). Sorry for the extra trouble, Alan Stern Index: usb-2.6/drivers/usb/storage/usb.c =================================================================== --- usb-2.6.orig/drivers/usb/storage/usb.c +++ usb-2.6/drivers/usb/storage/usb.c @@ -321,7 +321,7 @@ static int usb_stor_control_thread(void US_DEBUGP("*** thread awakened.\n"); /* Autoresume the device */ - autopm_rc = usb_autopm_get_interface_burst(us->pusb_intf); + autopm_rc = usb_autopm_get_interface(us->pusb_intf); /* lock the device pointers */ mutex_lock(&(us->dev_mutex)); ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel