Commit 03e3d9c2 authored by Mathias Nyman's avatar Mathias Nyman Committed by Greg Kroah-Hartman
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xhci: dbc: Improve performance by removing delay in transfer event polling. 



Queue event polling work with 0 delay in case there are pending transfers
queued up. This is part 2 of a 3 part series that roughly triples dbc
performace when using adb push and pull over dbc.

Max/min push rate after patches is 210/118 MB/s, pull rate 171/133 MB/s,
tested with large files (300MB-9GB) by Łukasz Bartosik

First performance improvement patch was commit 31128e74
("xhci: dbc: add dbgtty request to end of list once it completes")

Cc: Łukasz Bartosik <ukaszb@chromium.org>
Signed-off-by: default avatarMathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241227120142.1035206-2-mathias.nyman@linux.intel.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent d7123c77

drivers/usb/host/xhci-dbgcap.c

+1 −1
Original line number Diff line number Diff line
@@ -957,7 +957,7 @@ static void xhci_dbc_handle_events(struct work_struct *work) 
		/* set fast poll rate if there are pending data transfers */

		if (!list_empty(&dbc->eps[BULK_OUT].list_pending) ||

		    !list_empty(&dbc->eps[BULK_IN].list_pending))

			poll_interval = 1;

			poll_interval = 0;

		break;

	default:

		dev_info(dbc->dev, "stop handling dbc events\n");