On Wed, Aug 15, 2012 at 11:02:37AM +0200, Jiri Kosina wrote: > On Tue, 14 Aug 2012, Russell King wrote: > > > > Actually, Henrik (added to CC) has been doing some latency improvements > > > both for input core in general, and for HID devices as well lately. I > > > still have his patchset in my to-review queue, as I have just came back > > > from offline vacation, but the patch below definitely can't hurt and > > > should significantly lower the time spent in handling the irq for hid > > > device in common situation (i.e. noone listening for debugfs events). > > > > > > Could you please measure how much it helps on your system? > > > > Ok, it looks like it's changed the maximum USB interrupt execution > > time from around 364us to 255us. > > > > If I also do a similar trick with the debug code in hid_input_report() > > then I get down to 212us - iow, something like the patch below. > > Are you testing with kernel that contains b94e3c94aae04 already? That > should cover that case. No - the kernel I'm dealing with is unfortunately based upon v3.5.0-rc5 with many other patches on top (which add support for this platform.) However, I'll pick that commit into this tree. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
