Author: shurd Date: Fri Nov 9 22:18:43 2018 New Revision: 340310 URL: https://svnweb.freebsd.org/changeset/base/340310
Log: Fix first-packet completion The first packet after the ring is initialized was never completed as isc_txd_credits_update() would not include it in the count of completed packets. This caused netmap to never complete a batch. See PR 233022 for more details. PR: 233022 Reported by: lev Reviewed by: lev MFC after: 3 days Sponsored by: Limelight Networks Differential Revision: https://reviews.freebsd.org/D17931 Modified: head/sys/dev/e1000/em_txrx.c head/sys/dev/e1000/igb_txrx.c Modified: head/sys/dev/e1000/em_txrx.c ============================================================================== --- head/sys/dev/e1000/em_txrx.c Fri Nov 9 21:45:42 2018 (r340309) +++ head/sys/dev/e1000/em_txrx.c Fri Nov 9 22:18:43 2018 (r340310) @@ -458,7 +458,13 @@ em_isc_txd_credits_update(void *arg, uint16_t txqid, b ntxd = scctx->isc_ntxd[0]; do { delta = (int32_t)cur - (int32_t)prev; + /* + * XXX This appears to be a hack for first-packet. + * A correct fix would prevent prev == cur in the first place. + */ MPASS(prev == 0 || delta != 0); + if (prev == 0 && cur == 0) + delta += 1; if (delta < 0) delta += ntxd; DPRINTF(iflib_get_dev(adapter->ctx), Modified: head/sys/dev/e1000/igb_txrx.c ============================================================================== --- head/sys/dev/e1000/igb_txrx.c Fri Nov 9 21:45:42 2018 (r340309) +++ head/sys/dev/e1000/igb_txrx.c Fri Nov 9 22:18:43 2018 (r340310) @@ -333,7 +333,13 @@ igb_isc_txd_credits_update(void *arg, uint16_t txqid, ntxd = scctx->isc_ntxd[0]; do { delta = (int32_t)cur - (int32_t)prev; + /* + * XXX This appears to be a hack for first-packet. + * A correct fix would prevent prev == cur in the first place. + */ MPASS(prev == 0 || delta != 0); + if (prev == 0 && cur == 0) + delta += 1; if (delta < 0) delta += ntxd; _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
