Date: Fri, 31 Jul 2015 09:12:32 +0000 (UTC) From: Hans Petter Selasky <hselasky@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r286118 - head/sys/dev/usb/controller Message-ID: <201507310912.t6V9CW6D027713@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: hselasky Date: Fri Jul 31 09:12:31 2015 New Revision: 286118 URL: https://svnweb.freebsd.org/changeset/base/286118 Log: Limit the number of times we loop inside the DWC OTG poll handler to avoid starving other fast interrupts. Fix a comment while at it. MFC after: 1 week Suggested by: Svatopluk Kraus <onwahe@gmail.com> Modified: head/sys/dev/usb/controller/dwc_otg.c Modified: head/sys/dev/usb/controller/dwc_otg.c ============================================================================== --- head/sys/dev/usb/controller/dwc_otg.c Fri Jul 31 09:10:56 2015 (r286117) +++ head/sys/dev/usb/controller/dwc_otg.c Fri Jul 31 09:12:31 2015 (r286118) @@ -2551,12 +2551,18 @@ static void dwc_otg_interrupt_poll_locked(struct dwc_otg_softc *sc) { struct usb_xfer *xfer; + uint32_t count = 0; uint32_t temp; uint8_t got_rx_status; uint8_t x; repeat: - /* get all channel interrupts */ + if (++count == 16) { + /* give other interrupts a chance */ + DPRINTF("Yield\n"); + return; + } + /* get all host channel interrupts */ for (x = 0; x != sc->sc_host_ch_max; x++) { temp = DWC_OTG_READ_4(sc, DOTG_HCINT(x)); if (temp != 0) {
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201507310912.t6V9CW6D027713>